Transport Canada
May 17, 2016
TRANSPORT CANADA
PIEVC CLIMATE CHANGE VULNERABILITY ASSESSMENT
CAMBRIDGE BAY AIRPORT
FINAL
PROJECT NO.: 0727-004 DATE: May 17, 2016 DOCUMENT NO.: 0727004-16-03
Suite 500 - 980 Howe Street Vancouver, BC Canada V6Z 0C8 Telephone (604) 684-5900 Fax (604) 684-5909
May 17, 2016 Project No.: 0727004
Janice Festa, Senior Policy Advisor Transport Canada 330 Sparks Street Ottawa, ON, K1A 0N5
Dear Mrs. Festa, Re: PIEVC Climate Change Vulnerability Assessment: Cambridge Bay Airport - FINAL Please find attached the final version of our above-referenced report. Thank you for the opportunity to work on this assessment. Should you have any questions, please do not hesitate to contact the undersigned.
Yours sincerely,
BGC ENGINEERING INC. per:
Lukas Arenson, Dr.Sc.Techn.ETH, P.Eng. Senior Geotechnical Engineer
Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
EXECUTIVE SUMMARY
BGC Engineering Inc. (BGC) was commissioned by Transport Canada (TC) in partnership with the Government of Nunavut Territories and with Engineers Canada to apply the vulnerability assessment protocol to the Cambridge Bay Airport. The assessment follows a standardized protocol prepared by the Public Infrastructure Engineering Vulnerability Committee (PIEVC). The airport is located on Victoria Island, Nunavut, approximately 2.6 km west of the hamlet of Cambridge Bay, and is owned by the Government of Nunavut. It was constructed in the 1950s and is the only airport in Canada where jet aircraft land on a gravel runway. Runway 13-31T is 5000 ft long, currently extended to 6000 ft. In 2015, about 4,600 aircraft movements were recorded, of which 11% were jet aircraft movements. The initial assessment looked at a 30 year projected trend in climate conditions for the Cambridge Bay region, which are based on information from historic data and climate models. Key trends are: • mean annual air temperature is increasing at about 0.6 °C per decade with warming rates greatest in winter and fall; • the number of annual freeze/thaw cycles is decreasing by less than one cycle per decade; • annual rainfall is increasing by 5 mm per decade with the maximum number of intense rainfall days occurring in the months of July and August; • first snow days are occurring later in the season whereas last snow days show no statistically significant trend; • no statistically significant trend was identified in annual total snowfall; and • no statistically significant trend was identified for changes in wind direction and intensity. In total, 24 infrastructure components and 32 climate events were identified that result in 768 potential infrastructure - climate event combinations. Those combinations would need to be discussed in detail amongst various parties to identify high and medium rick combinations. Based on the data available and our understanding of the current airport infrastructure performance, no immediate engineering action is required for Cambridge Bay Airport. The assessment suggests that five climate events may be critical: rainfall, visibility, frost, ground thawing index, and climate variability. Changes in those climate events may affect airport operations and infrastructure performance in the future and result in negative impacts on the community of Cambridge Bay for which an operating airport is a critical link in connecting to other Northern communities and the South. However, there are currently insufficient detailed data available and the occurrence of these climate events is difficult to project with confidence. In addition, current environmental and maintenance baseline data are inadequate for carrying out a detailed engineering assessment. The lack of data and understanding is an unknown that is itself a moderate risk. This risk is one that can be mitigated by setting up and operating monitoring for the next several years. It is suggested that a monitoring program be designed and implemented as soon as possible. Therefore, it is recommended to collect and record such baseline data in a systematic manner to https://coreshack.bgcengineering.ca/projects/tcairport/del/Project Reports/Cambridge Bay/Cambridge Bay Climate Vulnerability Report.docx Page i BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004 provide input for making informed decisions for allocating resources and for designing mitigation and adaptation strategies if those were needed. This will also help in reviewing current operation practices and assessing their value for future climate conditions. Specifically, it is recommended: • Evaluate the capacity of drainage systems to assess the resiliency of culverts and ditches against higher flows, and measure runoff and changes in surface water bodies; • Systematically collect information on the visibility in the form of detailed logbook /database on the weather conditions at the time and the characteristics of the limited visibility event; • Collect data on frost formation, such as climate parameters, timing, location and extent; • Review frost management procedures; • Update or develop an asset management system, including an evaluation of current infrastructure service lives; • Monitor local snow accumulation, including spatial (re-)distribution and note limitations to operations; • Automated measurement of ground temperatures at various locations across the airport property; • Document in a logbook / database climate-related flight delays/cancellations, as well as maintenance and repair activities, including date, location, type and extent; and • Carry out an initial climate change vulnerability assessment with several stakeholders that include the airport operators, the owners and users of the airport, and re-evaluate it every five years, as new baseline data, infrastructure performance information, and improved climate models become available. The changing climate will likely result in increased maintenance and repair efforts for which resources must be available.
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TABLE OF CONTENTS
EXECUTIVE SUMMARY ...... i TABLE OF CONTENTS ...... iii LIST OF TABLES ...... iv LIST OF FIGURES ...... v LIST OF APPENDICES ...... vi LIMITATIONS ...... vii 1.0 INTRODUCTION ...... 1 1.1. Background ...... 1 1.2. Purpose and Scope ...... 1 1.3. PIEVC Protocol for Climate Change Vulnerability Assessment ...... 2 1.3.1. Step 1 – Project Definition ...... 3 1.3.2. Step 2 – Data Gathering and Sufficiency ...... 3 1.3.3. Step 3 – Risk Assessment (limited) ...... 4 1.3.4. Step 4 – Engineering Analysis (not carried out) ...... 4 1.3.5. Step 5 – Recommendations (limited) ...... 5 1.4. Project Team ...... 5 1.5. Report Layout ...... 5 2.0 STEP 1 – PROJECT DEFINITION ...... 7 2.1. Permafrost and Infrastructure ...... 7 2.2. Climate Change Effects on Infrastructure in Permafrost ...... 8 2.3. Identifying the Infrastructure ...... 9 2.3.1. General Site Description ...... 9 2.3.2. Current Conditions ...... 12 2.3.3. Elements of Infrastructure Assessed ...... 15 2.3.4. Data Sources ...... 16 2.4. Identifying Climate Factors ...... 16 2.5. Identifying Time Factors ...... 19 2.6. Identifying Jurisdictional Considerations ...... 19 2.7. Assessment of Data Sufficiency ...... 19 2.7.1. Infrastructure Data ...... 19 2.7.2. Climate Data ...... 20 2.7.3. Subsurface Data ...... 20 2.8. Summary of Risk Assessment Workshop ...... 20 3.0 STEP 2 – DATA GATHERING AND DATA SUFFICIENCY ...... 21 3.1. Infrastructure Components ...... 21 3.1.1. Physical Infrastructure ...... 21 3.1.2. Supporting and Maintenance Systems/Infrastructure ...... 21 3.1.3. Other ...... 22 3.2. Performance Response ...... 23 https://coreshack.bgcengineering.ca/projects/tcairport/del/Project Reports/Cambridge Bay/Cambridge Bay Climate Vulnerability Report.docx Page iii BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
3.3. Climate Baseline...... 23 3.4. Climate Change Assumptions ...... 24 3.5. Changes in Climate Parameters ...... 26 3.5.1. Air Temperature ...... 27 3.5.2. Frost ...... 27 3.5.3. Precipitation ...... 27 3.5.4. Others ...... 28 3.5.5. Climate Variability ...... 28 3.5.6. IDF Curves ...... 28 3.5.7. Perceived Sensitivities to Climate Change ...... 29 3.6. Historical Climate Extremes ...... 29 3.7. Time Frame ...... 30 3.8. Geography and Permafrost ...... 30 3.9. Jurisdictional Considerations ...... 30 3.10. Potential Changes that May Affect the Infrastructure ...... 30 4.0 STEP 3 – RISK ASSESSMENT ...... 31 4.1. Performance Response of the Infrastructure Component ...... 32 4.2. Potential Climate Events ...... 33 4.3. Probability Estimation ...... 34 4.4. Severity Estimation ...... 35 5.0 DISCUSSION AND RECOMMENDATIONS ...... 37 5.1. Preamble ...... 37 5.2. Limitations ...... 37 5.3. Discussion ...... 37 5.4. Recommendations ...... 38 5.5. Master Plan 2010 ...... 39 6.0 CONCLUSIONS ...... 41 7.0 CLOSURE ...... 43 REFERENCES ...... 44
LIST OF TABLES
Table 2-1. Average annual climate conditions, Cambridge Bay (1981-2010) (Environment Canada, 2016)...... 17 Table 2-2. Thawing and freezing days, Cambridge Bay (1981-2010) (Environment Canada, 2016)...... 18 Table 2-3. Visibility and cloud cover, Cambridge Bay (1981-2010) (Environment Canada, 2016)...... 18 Table 3-1. Comments on selected physical infrastructure...... 21
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Table 3-2. Overview of maintenance elements...... 22 Table 3-3. Overview of supporting systems and infrastructure...... 22 Table 3-4. Performance response considerations...... 23 Table 3-5. Climate Effects and potential change factors and impacts...... 24 Table 3-6. Historical climate trends, Cambridge Bay (1986-2015)...... 26 Table 3-7. Climate parameters related to air temperatures...... 27 Table 3-8. Climate parameters related to precipitation...... 27 Table 3-9. Other climate parameters...... 28 Table 3-10. Potential changes that may affect the airport infrastructure...... 30 Table 4-1. Risk tolerance thresholds used for this assessment adapted from the Protocol (Canadian Council of Professional Engineers, 2012)...... 31 Table 4-2. Performance response prioritization methodology...... 32
LIST OF FIGURES
Figure 1-1. Overview of the PIEVC Protocol flow chart (after Canadian Council of Professional Engineers, 2012)...... 3 Figure 2-1. Permafrost extents in Canada (Natural Resources Canada, 1995)...... 7 Figure 2-2. Cambridge Bay Airport location obtained from Google Earth, 2016...... 9 Figure 2-3. Cambridge Bay location obtained from Google Earth, 2016...... 10 Figure 2-4. Cambridge Bay Airport aircraft movement, 2004-2015 (Statistics Canada, 2015)...... 11 Figure 2-5. Thermokarst pond adjacent to the airport road, northeast of the runway, Cambridge Bay, Nunavut. Construction of road blocked natural drainage causing surface ponding of water that has then thawed ice- rich sediments below. Continued growth of the pond is seen by radially extending slump scars and collapse of 10– 25 cm thick mats of peat into the pond. This exposes underlying sediments to thaw and further settlement (Smith and Forbes, 2014)...... 12 Figure 2-6. Cambridge Bay Airport runway looking north-west (www.airport- data.com)...... 13 Figure 2-7. Surficial movement rates based on InSAR analysis (3vGeomatics, 2011). Image: Google Earth, August 2011...... 14 https://coreshack.bgcengineering.ca/projects/tcairport/del/Project Reports/Cambridge Bay/Cambridge Bay Climate Vulnerability Report.docx Page v BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
Figure 2-8. Mean monthly air temperature and precipitation totals, Cambridge Bay (1981-2010) (Environment Canada, 2016)...... 17 Figure 4-1. Methods to estimate the probability scale factors according to Canadian Council of Professional Engineers (2012). Method A is recommended for this assessment...... 35 Figure 4-2. Methods to estimate the severity scale factors according to Canadian Council of Professional Engineers (2012). Method E is recommended for this assessment...... 36
LIST OF APPENDICES
PHOTOGRAPHS APPENIDX A CLIMATE INFORMATION ANALYSIS APPENDIX B CLIMATE CHANGE VULNERABILITY ASSESSMENT MATRIX - DRAFT APPENDIX C WORKSHOP PRESENTATION APPENDIX D NON-TECHNICAL EXECUTIVE SUMMARY
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LIMITATIONS
BGC Engineering Inc. (BGC) prepared this document for the account of Transport Canada. The material in it reflects the judgment of BGC staff in light of the information available to BGC at the time of document preparation. Any use which a third party makes of this document or any reliance on decisions to be based on it is the responsibility of such third parties. BGC accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions based on this document. As a mutual protection to our client, the public, and ourselves, all documents and drawings are submitted for the confidential information of our client for a specific project. Authorization for any use and/or publication of this document or any data, statements, conclusions or abstracts from or regarding our documents and drawings, through any form of print or electronic media, including without limitation, posting or reproduction of same on any website, is reserved pending BGC’s written approval. A record copy of this document is on file at BGC. That copy takes precedence over any other copy or reproduction of this document.
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1.0 INTRODUCTION
1.1. Background In August 2005, Engineers Canada established a national committee known as the Public Infrastructure Engineering Vulnerability Committee (PIEVC) to oversee the planning and execution of a broad-based national engineering assessment of the vulnerability of Canadian public infrastructure to climate change. This is a continuing priority for the engineering profession because of the uncertainties caused by a changing climate that may influence the validity of climatic design parameters, which are generally based on historical data. The PIEVC developed a vulnerability assessment method that follows a structured risk assessment protocol known as the PIEVC Engineering Protocol (the Protocol). The Protocol has been tested on more than 40 projects since 20071. The Protocol is structured in such a way that the infrastructure vulnerability is evaluated in a staged process. The observations, conclusions and recommendations derived from the Protocol are intended to provide information for the decision-maker about design, construction, operation, maintenance, planning and development. Transport Canada (TC), together with the Government of Nunavut, selected Cambridge Bay as the airport to be assessed using the PIEVC Protocol. The airport is located in a zone of continuous permafrost and potentially susceptible to changes thereof. The objective of this assessment is to identify potential vulnerabilities of the airport infrastructure to future climate change. The results of this assessment will be used to guide substantiated engineering and planning recommendations for management and remedial action to address those components of the airport infrastructure that are at the highest risk of failure, damage or deterioration to future changes in local climate.
1.2. Purpose and Scope BGC Engineering Inc. (BGC) was retained by TC to carry out an assessment of Cambridge Bay Airport and its vulnerability to climate change. The contract (No. T8080-140109) was awarded to BGC on March 24, 2015. The infrastructure for the airport that is included under the scope of the vulnerability assessment following the PIEVC Protocol comprises of: • Structural elements (e.g., runway structures); • Policies and procedures (e.g., emergency preparedness and response plans, asset management, operations and maintenance practices); and • Support equipment (e.g., HVAC, backup power and control systems). The assessment does not include non-structural building elements or accessory equipment, such as seating in the terminal or signage. In addition, the scope of the assessment encompasses the
1 http://pievc.ca/
Cambridge Bay Climate Vulnerability Report.docx Page 1 BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004 current design, construction, operation and management of this infrastructure as well as any planned upgrades or major rehabilitation projects in the planning stages. During a conference call between TC and BGC on January 15, 2016, it was agreed to reduce the original scope as only limited data were available and the risk workshop, which forms an essential part of the vulnerability assessment, could not be carried out as planned. The updated scope of work therefore included the following: 1. Define the infrastructure components for the airport runway and associated structures that encompass its physical infrastructure, supporting systems, maintenance and operation, and other considerations; 2. Determine the likely effects of climate change on individual components of the infrastructure; 3. Outline potential climate event and infrastructure component interactions; 4. Provide recommendations for future analysis; and 5. Prepare a report and presentation slides. Due to the limited data available and the lack of people knowledgeable about the design, use and operation of the airport, the work was not completed as per the Protocol. However, this document can be used in the future if an assessment using the Protocol is desired. The recommendations provided in this document are therefore of a general nature and must be evaluated in detail prior to their implementation.
1.3. PIEVC Protocol for Climate Change Vulnerability Assessment The PIEVC developed a generalized step-by-step protocol to assess the vulnerability of infrastructure to climate change. BGC used Revision PG-10 (Canadian Council of Professional Engineers, 2012) of the Protocol for the assessment. The Protocol provides a structured framework that can be used for any infrastructure. It has been successfully used to assess the following categories: • Various types of buildings; • Roads, bridges and associated structures, such as culverts; • Stormwater and wastewater treatment and collection systems; • Water resource systems and other water management infrastructure; • Energy transmission and distribution systems; and • Airports. The Protocol structures the climate change vulnerability assessment into five main steps: • Step 1 – Project Definition • Step 2 – Data Gathering and Sufficiency • Step 3 – Risk Assessment • Step 4 – Engineering Analysis • Step 5 – Recommendations The development of these steps is shown in Figure 1-1 and described in the subsections that follow. Additional information is available in PIEVC (2012).
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Figure 1-1. Overview of the PIEVC Protocol flow chart (after Canadian Council of Professional Engineers, 2012).
Note: For Cambridge Bay Airport, only Steps 1 – 3 were carried out. The Risk Assessment (Step 3) and the Engineering Analysis (Step 4) could not be completed as per the Protocol and as such, only limited and general Recommendations (Step 5) are provided.
1.3.1. Step 1 – Project Definition In the first step of the vulnerability assessment protocol, global project parameters and boundary conditions are defined. This step includes the definition of the following: • Infrastructure to be assessed; • Its location; • Climatic and geographic considerations; and • Uses of infrastructure. The goal of this step is to narrow the focus and allow for an efficient data acquisition.
1.3.2. Step 2 – Data Gathering and Sufficiency Further details regarding the infrastructure and the particular climate effects that are being considered are evaluated in this second project step. The sufficiency of the gathered data due to: i) poor quality; ii) high levels of uncertainties; or iii) lack of data altogether, is assessed. This step further focuses on evaluating and starting initiatives to counter these insufficiencies.
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Specifically, Step 2 defines the following for the project: • Infrastructure components; • Climate baseline; • Climate change assumptions; • Time frame; • Geography; • Jurisdictional considerations; and • Other potential changes that may affect the infrastructure
1.3.3. Step 3 – Risk Assessment (limited) During the risk assessment, the infrastructure’s response to climate events is evaluated. The protocol uses a spreadsheet to examine the interaction between the infrastructure and climate events. Therefore, lists are developed of relevant climate events and relevant infrastructure components. An essential component of Step 3 is the holding of a workshop with the infrastructure operations, management and engineering staff, and other relevant individuals. At the workshop, results of the initial risk assessment are reviewed. The workshop participants then assess the probabilities and severities of the interactions identified. The risk assessment worksheet is then updated based on the input from the workshop participants. Ideally, participants at the workshop include the following: • The practitioner team; • Representatives from the infrastructure management team; • Representatives from the infrastructure engineering team; • Representatives from the infrastructure operations team; • Local expertise/knowledge regarding severe climatic events in the region and climatic events that may have affected the infrastructure; • Representatives from the organization providing climate information; • Representatives from any advisory groups or technical experts who may be supporting the vulnerability assessment; and • Others deemed necessary by the infrastructure owner or practitioner team.
1.3.4. Step 4 – Engineering Analysis (not carried out) In Step 4, a focused engineering analysis is conducted on the interactions requiring further assessment, as identified in Step 3 (risk assessment). The engineering analysis requires a numerical assessment of: The total load on the infrastructure, comprising: • Current load on the infrastructure; • Projected change in load arising from climate change effects on the infrastructure; and • Projected change in load arising from other change effects on the infrastructure.
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The total capacity of the infrastructure, comprising: • Existing capacity; • Projected change in capacity arising from aging/use of the infrastructure; and • Other factors that may affect the capacity of the infrastructure. One final data availability and quality assessment is carried out. If the data quality or statistical error does not support clear conclusions from this step, the Protocol directs to revisit Step 1 and/or Step 2 to acquire and refine the data to a level sufficient for more robust engineering analysis. At the end of this step, recommendations based on analysis are made (Step 5) and the need for additional/refined risk assessments is evaluated (Step 3).
1.3.5. Step 5 – Recommendations (limited) Recommendations are developed from the work completed in the previous steps. Generally, the recommendations will fall into five major categories: • Remedial action is required to upgrade the infrastructure; • Management action is required to account for changes in the infrastructure capacity; • Continue to monitor performance of infrastructure and re-evaluate at a later time; • No further action is required; and • There are gaps in data availability or data quality that require further work. Additional conclusions or recommendations may be identified regarding the veracity of the assessment, the need for further work, or areas that were excluded from the current assessment.
1.4. Project Team The climate change vulnerability assessment was executed by the following BGC project team: • Jack Seto, M.Sc., P.Eng., P.E. • Lukas Arenson, Dr.Sc.Techn.ETH, P.Eng. • Midori Telles-Langdon, B.A.Sc., E.I.T., G.I.T. Input was provided by: • Jenna Craig, Transport Canada • Janice Festa, Transport Canada • Nemanja Jevtovic, Transport Canada • Darren Locke, Government of the Northwest Territories • Wiz Mohammed, Government of Nunavut
1.5. Report Layout The case study has been executed to follow as practically possible, the process defined in the Protocol. This report describes how the Protocol was implemented, presents the results obtained, and provides recommendations for Cambridge Bay Airport. This document is laid out as follows:
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• Section 2: Project Definition. Following Step 1 of the Protocol, the infrastructure, climate history and identification of resources are identified. • Section 3: Data Gathering and Sufficiency. Following Step 2 of the Protocol, more details are presented on the infrastructure parts assessed and the particular climate factors / projections being considered. • Section 4: Risk Assessment. An overview of the risk assessment is described and considerations for a risk evaluation outlined. • Section 5: Recommendations. Recommendations for further actions are summarised based on the information available. • Section 6: Conclusions. Conclusions drawn from the vulnerability assessment are summarized. • Series of photographs of Cambridge Bay Airport. • Appendix A: Climate Data Analysis. An analysis for historical and projected climate trends for the Cambridge Bay area; including Figures. • Appendix B: Template of the Climate Change Vulnerability Matrix for Cambridge Bay Airport. • Appendices C and D provide slides of the workshop presentation and a non-technical summary of the work performed, respectively.
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2.0 STEP 1 – PROJECT DEFINITION This section describes the global project parameters and provides background information on permafrost, the infrastructure, potential climate factors, and boundary conditions of relevance. It also assesses the data sufficiency. This first step is intended to narrow the focus to allow for an efficient engineering vulnerability assessment.
2.1. Permafrost and Infrastructure Permafrost is defined as ground (soil, peat, rock) that remains below 0 °C for more than two consecutive years (National Research Council Canada, 1988). Within the Canadian context of permafrost distribution, the areas which contain permafrost include alpine regions and northern Canada (Figure 2-1). In the more northerly regions, permafrost is generally continuous over the landscape. Progressing southward, permafrost becomes discontinuous, with a decreasing proportion of the landscape containing permafrost. In the most southerly instances of permafrost, isolated pockets of permafrost are encountered in a landscape largely devoid of permafrost, which is referred to as sporadic permafrost.
Cambridge Bay
Figure 2-1. Permafrost extents in Canada (Natural Resources Canada, 1995).
Factors which influence the distribution and temperature of permafrost include: • Air temperature, which is in turn influenced by: • Latitude; • Elevation; • Topography; • Proximity to water bodies; and
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• Weather patterns; • Thermal properties of the soil or rock; • Heat required to convert water into ice when freezing (or ice into water when thawing) termed latent heat; • Presence of insulative material on the ground surface (muskeg, snow, vegetation); • Presence of infrastructure (e.g., embankment, building foundation type); • Exposure to convective air movement (i.e., wind); • Exposure to radiative energy (i.e., direct sunlight); • The reflective/absorbance of radiative energy due primarily to the color of the surface (light colors reflecting more energy, dark colors absorbing more energy) referred to as the albedo of the surface; • Vegetation; • Precipitation; and • Surface water. The special and extreme environment requires unique engineering and infrastructure solutions that account for severe climate conditions, presence of potentially ice-rich permafrost and various cryogenic processes. The strength and deformation characteristics of frozen soils are dependent on soil type, temperature, density, ice content, unfrozen water content, salinity, stress state, and strain rate (Arenson et al., 2014). Changes in temperature and in particular the thawing of frozen soil, may lead to significant changes in the strength and deformation characteristics, resulting in accelerated settlement and possible foundation failure. In consequence, foundation design must include an evaluation of the maximum active layer (seasonal thaw) thickness and permafrost temperature that may occur in the foundation soils during the lifetime of the structure.
2.2. Climate Change Effects on Infrastructure in Permafrost As outlined by Instanes et al. (2005), the potential effects of increasing mean annual ground surface temperature on permafrost will be very different for continuous and discontinuous permafrost zones. In the continuous zones, increasing air temperatures are very likely to increase permafrost temperatures and possibly increase the depth of the active layer. In the discontinuous zone, the effects of a few degrees increase in the mean annual permafrost temperature are very likely to be substantial (Harris, 1986). Since the temperature of most of this permafrost is presently within a few degrees of the melting point, the permafrost is likely to disappear. However, except for the southernmost zone of sporadic permafrost, many centuries will likely be required for the frozen ground to disappear entirely. But, increases in active layer depths and thawing of the warmest permafrost from the top are already ongoing in response to current warming. Construction activities on their own affect the surface conditions, and ultimately the ground temperatures due to anthropogenic changes in the insulation cover, snow distribution, hydrology, vegetation and Albedo. The thermal and mechanical response of the foundation to the constructed infrastructure, such as accelerated creep or thaw consolidation, may be very slow.
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Additionally, changes in permafrost are induced due to climate change. Due to the superposition of anthropogenic and climate change induced changes in the ground thermal regime and the associated time lags, it may be difficult to clearly identify the source of the induced changes. If the infrastructure has not been designed to account for potential climate change, it may not have sufficient capacity in the future.
2.3. Identifying the Infrastructure
2.3.1. General Site Description The Cambridge Bay Airport has been in use since the 1950s. The airport is located on Victoria Island, Nunavut, approximately 2.6 km west of the hamlet of Cambridge Bay, and is owned by the Government of Nunavut (see Figure 2-2 and Figure 2-3) (EBA, 2012). Located in the Kitikmeot Region of the western arctic, the Cambridge Bay airport is the third busiest gateway airport in Nunavut and the base of Medevac for the entire region (LPS Aviation, 2010).
Figure 2-2. Cambridge Bay Airport location obtained from Google Earth, 2016.
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Figure 2-3. Cambridge Bay location obtained from Google Earth, 2016.
As shown in Figure 2-4 below, aircraft movements at the Cambridge Bay Airport have been observed to be decreasing over the past six years. However, long-term air traffic trends at this airport are expected to increase. As of 2010, Cambridge Bay was the only airport in Canada where jet aircraft land on a gravel runway (LPS Aviation, 2010), being responsible for 10 – 15% of all movements. Based on the Master Plan 2010 (LPS Aviation, 2010) a steady growth in passengers between 2.2 and 3.1% is estimated by 2030, despite recent decrease in aircraft movements. Together with a similar growth in cargo, this results in a projected increase in air traffic movements of 8,100 per year in 2030. In addition, the Canadian High Arctic Research Station (CHARS) which is planned to be completed in 2017 will attract Canadian and international scientists to work on science and technology issues in Canada's North. This may result in additional aircraft movement for personnel and cargo.
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7,000
6,000
5,000
4,000
3,000
2,000 TotalAircraft Movements
1,000
0 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
Figure 2-4. Cambridge Bay Airport aircraft movement, 2004-2015 (Statistics Canada, 2015).
Cambridge Bay lies within the zone of continuous permafrost (Figure 2-1), with a thin – typically less than 1 m thick – active layer (Smith and Forbes, 2014). Much of the Cambridge Bay region is generally covered by a thin layer of coarse, well-drained sediment overlying bedrock. This setting has resulted in the absence of ground-ice features on the ground surface. However, unconsolidated sediments in the region may well contain interstitial ice. The area of the airport is situated on glacial and glaciofluvial deposits of thicknesses varying between 1 and 5 m overlying bedrock. The glacial deposits are primarily comprised of sandy clay and silt tills (EBA, 2012). The finer sediments in this part of Cambridge Bay are further reflected by evidence of massive ground ice and excess ice (ice wedges and thermokarst depressions) found in low-lying surrounding ponds in the area close to the airport, such as the thermokarst pond located northeast of the airport runway (Figure 2-5).
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Figure 2-5. Thermokarst pond adjacent to the airport road, northeast of the runway, Cambridge Bay, Nunavut. Construction of road blocked natural drainage causing surface ponding of water that has then thawed ice-rich sediments below. Continued growth of the pond is seen by radially extending slump scars and collapse of 10– 25 cm thick mats of peat into the pond. This exposes underlying sediments to thaw and further settlement (Smith and Forbes, 2014).
Furthermore, because the area was submerged below sea level following deglaciation and has subsequently been uplifted, saline ground ice conditions are likely affecting the unfrozen water content and its mechanical properties at temperatures close to 0 °C (e.g., Biggar and Sego, 1993; Hivon and Sego, 1993). Unconsolidated sediments on gentle slopes, such as on the south west side of the runway, are subject to gelifluction, the slow downslope movement of earth materials on the permafrost table. The rate of ground movements is movements is slow, but requires regrading as part of regular surface maintenance. Based on a recent report by Lemmen et al. (2016) the relative sea level rise along the costs of Cambridge Bay by 2100 is between 0 and 25 cm. The report further concluded that there is only a low to moderate coastal sensitivity to climate change.
2.3.2. Current Conditions Cambridge Bay Airport (IATA: YCB, ICAO: CYCB) is located at 90 m above sea level, with a gravel surfaced runway that is 5000 ft (1524 m) long and 150 ft (46 m) wide (Figure 2-6). The runway number is 13-31T.
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Figure 2-6. Cambridge Bay Airport runway looking north-west (www.airport-data.com).
The Nunavut Airports 20 Year Infrastructure Needs Assessment, 2014-2034 (LPS Aviation, 2014) outlines the need for the Cambridge Airport to be paved and extended to 6000 ft in order to accommodate future aircraft types. As of the April 2014 report, and confirmed during BGC’s site visit in July 2015, the runway, taxiway, and apron surfaces were being resurfaced with gravel, to be completed in 2015. Upgrades to the airfield electrical systems is also underway (LPS Aviation, 2014). A study on surficial deformation at the Cambridge Bay region, using InSAR technology prepared by 3vGeomatics (2011) highlights that currently, surficial deformations, mainly in the form of heave are noted in the eastern side of the apron and along the runway side slopes (Figure 2-7). However, some areas along the runway also show settlements of similar magnitude, highlighting the heterogeneity in surface deformations in a permafrost terrain. Based on current understanding of the permafrost at Cambridge Bay, only moderate impacts on the runway integrity due to climate change are expected.
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Figure 2-7. Surficial movement rates based on InSAR analysis (3vGeomatics, 2011). Image: Google Earth, August 2011.
WorleyParsons (2013) carried out a geotechnical site investigation for the current airport expansion. Twenty test pits were excavated to a maximum depth of 2.4 m. Thin organic peat deposits, ranging in thickness from 50 mm to 200 mm along the existing runway and up to 400 mm thick in outlying areas were reported. As was common practice at the time of construction in the 1950's, fill appeared to have been placed directly on top of any existing peat deposits; any consolidation and compression of these deposits would have been filled in during routine maintenance operations. WorleyParsons (2013) further indicated that the existing runway, taxiway and apron are all generally well-drained. Most of the areas adjacent to the runway are also well drained and trafficable to vehicles during the thaw season. However, the area located to the southeast of the existing apron and taxiway is low-lying and poorly drained. This observation corresponds well with the InSAR data from 3vGeomatics (2011). Access to this area with mechanized equipment (including the tracked excavator) is not possible during the thaw season. The report continues that based on conversations with the Airport Manager and maintenance personnel, the runway has generally performed well over the past 15 years. There has been no significant evidence of rutting, thaw settlements, frost heave or ice wedge cracking along the runway, taxiway or apron. The favourable performance history of the runway and parking aprons is consistent with regular maintenance, the generally good drainage conditions, inferred subsurface conditions and the method of construction.
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WorleyParsons (2013) recommend that at least 2 m of thaw-stable granular fill be provided below the finished surface of the taxiways and parking apron extension to provide an adequate bearing capacity for the wheel loads imposed by the design aircraft. If necessary, sub-excavation was recommended in some areas to achieve this minimum thickness of granular fill.
2.3.3. Elements of Infrastructure Assessed An overview of the infrastructure elements that should be considered in the vulnerability assessment is provided below. Sub-components were grouped into single components for some of the elements assessed. Detailed descriptions and rationales for the sub-component grouping can be found in Section 3.1. • Physical Components • Runway • Taxiways • Aprons • Drainage • Access and Service Roads • Heterogeneity in Natural Foundation/Permafrost • Supporting Infrastructure • Operations and Maintenance Personnel • Snow clearing • Resurfacing • Winter flight operation • Summer flight operation • Summer maintenance • Winter maintenance • Lighting systems • Surface markings • Environmental monitoring • Navaids • Vegetation • Security structures • Data availability • Others • Emergency procedures and medevac • Wildlife • Future development/Masterplan • Municipal Services
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2.3.4. Data Sources The following technical documents were available for the Cambridge Bay Airport and provided by Transport Canada: • Gravel Runway Requirements From A Manufacturer’s Point of View, Ken DeBord, 2010 • Cambridge Bay Airport Expansion Geotechnical Investigation, WorleyParsons Canada, 2013 • Phase II/III Environmental Site Assessment at Airport Shoreline in Cambridge Bay, NU. Report prepared for Public Works and Government Services Canada, EBA Engineering Consultants, Ltd., 2012. • Infrastructure for a Sustainable Cambridge Bay Vol. 2 Consultation Report, Aarluk Consulting Inc., 2011 • Master Plan 2010 Cambridge Bay Airport, LPS Aviation Inc., 2010 • Cambridge Bay Cumulative Displacement, 3vGeomatics, 2010 • Nunavut Terrain and Soil Analysis. Report submitted to Government of Nunavut, 3vGeomatics Inc. March 2011.
2.4. Identifying Climate Factors Weather data from the Cambridge Bay meteorological station, operated by Environment Canada (EC) were used. Cambridge Bay A station (WMO Identifier 71925) is located at the Cambridge Bay Airport, just to the east of the air terminal building (495,369 mE / 7,666,216 mN; WGS84, UTM Zone 13N). Daily records for this station date back to 1929. Additional data for the period from 2014-2015 was obtained from the nearby Cambridge Bay GSN station (WMO Identifier 71288), also located at the Cambridge Bay Airport. The mean annual air temperature for the climate normal period of 1981-2010 is -13.9 °C, with July typically being the warmest month and February the coldest. Average daily air temperatures remain above freezing from June to September. Cambridge Bay experiences on average 142 mm of total precipitation in a year, with the majority of precipitation falling from June to October. Snowfall generally occurs between the months of September to June, with occasional snowfall during July and August. The climate normals for Cambridge Bay over the period of 1981 to 2010 are summarised in Figure 2-8, and Table 2-1 to Table 2-3.
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Figure 2-8. Mean monthly air temperature and precipitation totals, Cambridge Bay (1981-2010) (Environment Canada, 2016).
Table 2-1. Average annual climate conditions, Cambridge Bay (1981-2010) (Environment Canada, 2016). Parameter Value Parameter Value Daily Average Temperature -13.9 °C Daily Maximum Temperature 1.3 °C Daily Minimum Temperature -10.4 °C Rainfall 72.1 mm Snowfall 80.2 cm Total Precipitation 141.7 mm Wind Speed 19.6 km/hr Most Frequent Direction Northwest Average Station Pressure 101.2 kPa
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Table 2-2. Thawing and freezing days, Cambridge Bay (1981-2010) (Environment Canada, 2016). Degree Days: > 24 °C > 18 °C > 15 °C > 10 °C > 5 °C > 0 °C 0 0.1 1.7 36.5 221.8 636.3 Degree Days: < 0 °C < 5 °C < 10 °C < 15 °C < 18 °C 5661.2 7072.9 8713.7 10505 11599.2
Table 2-3. Visibility and cloud cover, Cambridge Bay (1981-2010) (Environment Canada, 2016). Hours with Visibility: < 1 km 1 to 9 km > 9 km 325.7 1507.3 6932.2 Hours with Cloud Cover: 0 to 2/10 3/10 to 8/10 8/10 to 1 2375.4 1762.7 4627.2
Appendix A presents a more detailed analysis of the historical climate records and climate projections for the Cambridge Bay area. The following lists the potential change factors associated with each climate element: • Air Temperature • Rate of change • Mean values • Extremes (high summer/low winter) • Extreme wave durations (high summer/low winter) • Freezing and thawing indices • Ground Temperature • Rate of change • Freezing and thawing indices • Frost • Freeze/thaw cycles • Rainfall • Frequency • Duration • Intensity • Total annual/seasonal • Rain on snow • Freezing rain • Snowfall • Frequency • Duration • Total annual • First/last snow day
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• Wind • Gusts • Directional • Seasonal • Storms • Blizzards/White-outs • Ice storms • Hail • Lightning/electrical storms • Visibility • Fog • Cloud cover/solar radiation • Cloud ceiling height
2.5. Identifying Time Factors This project identifies climate projections from 2015 to 2045, a 30-year period. This time frame was decided upon by the project team as a suitable planning time frame for airport decision makers.
2.6. Identifying Jurisdictional Considerations The agency involved was Transport Canada. The standards listed below have been considered for today’s conditions. Information on the standards used for initial design of the various components was not available for the assessment. • Transport Canada: Aerodrome Standards and Recommended Practices, TP312 4th Edition, March 1993. • ICAO Annex 14, Aerodromes, Volume I - Aerodrome Design and Operations, 6th Edition. • National Standard of Canada CAN/CSA-S503-15. Community drainage system planning, design, and maintenance in northern communities, January 2015. • National Standard of Canada CAN/CSA- S501-14. Moderating the effects of permafrost degradation on existing building foundations, December 2014.
2.7. Assessment of Data Sufficiency
2.7.1. Infrastructure Data Relevant technical documents were provided to BGC by Transport Canada. The data are considered reasonably sufficient for the climate change vulnerability assessment. However, standards and design criteria that were used for the initial design were not available.
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2.7.2. Climate Data Climate data used for design and input into climate change projections are based on the historical observations from Environment Canada climate stations at Cambridge Bay Airport. Daily recorded data from January 1958 to December 2015 was used in the assessment. Data gaps exist, notably all data for 1992 and wind data for the period from 1995 to 2001. The reasons for these data gaps are unknown. Despite the data gaps, the data sufficiency was considered adequate for a vulnerability assessment.
2.7.3. Subsurface Data A geotechnical investigation report prepared by WorleyParsons (2013) described information on the subsurface soil conditions across the airport based on 20 test pits excavated in 2012, 14 test pits excavated in 2009, and their understanding of the local geology. The data sufficiency was considered adequate for a vulnerability assessment.
2.8. Summary of Risk Assessment Workshop A risk assessment workshop, intended to collect information regarding the condition of airport infrastructure and to discuss potential and previous issues with this infrastructure, did not take place. These discussions were intended to develop a risk assessment matrix, as outlined in PIEVC Protocol Step 3 (see Section 1.3.3). The workshop was to have been structured as follows: introduction, site visit, climate parameters, infrastructure components, and summary. The focus of these sessions were to discuss and assign probabilities (P) for a number of climate events that affect infrastructure components and then to assign severities of the consequences (S) to these climate events on the infrastructure components. Both parameters are assigned a value of 0 to 7, with the lower values representing low probability / consequence and the higher values representing high probability and severe consequences, in accordance with the PIEVC Protocol. The risk, R, is computed as the product of the probability and the severity. The values discussed during the workshop would then be incorporated into an initial risk matrix.
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3.0 STEP 2 – DATA GATHERING AND DATA SUFFICIENCY The goal of this step was to narrow the infrastructure components and relevant climate parameters to make the risk assessment more efficient, and to assess the sufficiency of these data with respect to the climate change vulnerability.
3.1. Infrastructure Components The infrastructure was grouped into components that are considered as a structural unit in its capacity and response to changes in the climate conditions. For example, the drainage system was not divided into individual components, such as culverts, berms, ditches or ponds. If a component (or system) is highlighted as being of medium or high risk, an in-depth assessment that looks at individual elements of that particular component would be carried out.
3.1.1. Physical Infrastructure The following physical infrastructure are considered and briefly commented on in Table 3-4. • Runway • Taxiways • Aprons • Drainage System • Access and Service Roads • Heterogeneity in Natural Foundation/Permafrost
Table 3-1. Comments on selected physical infrastructure. Element Comments Runway (Gravel-Surfaced) Consider structural aspects, including stability, runway friction, surface roughness and deflections Taxiways and Apron (Gravel-Surfaced) Consider structural aspects, including stability, friction, surface roughness and deflections Drainage (culverts and ditches) Capacity of the drainage system to safely convey water so that it does not impact the structural stability of the infrastructure or its functionality. Access and Service Roads Consider structural and functionality aspects
3.1.2. Supporting and Maintenance Systems/Infrastructure Supporting infrastructure components include the following elements: • Operations and Maintenance Personnel • Snow clearing • Resurfacing • Winter flight operation • Summer flight operation • Summer maintenance
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• Winter maintenance • Lighting systems • Environmental monitoring • Navaids • Vegetation • Security structures • Data availability Comments related to maintenance elements and other supporting elements that are either non- structural or have a supporting role are provided in Table 3-2 and Table 3-3, respectively.
Table 3-2. Overview of maintenance elements. Element Comments Operation and maintenance Availability and qualifications of airport operations and personnel maintenance personnel Winter flight operation General airport operations during winter Winter maintenance, including Maintenance activities required for safe operation during winter snow clearing Summer flight operation General airport operations during summer Summer maintenance, including Maintenance activities required for safe operation during summer crack filling and surface markings
Table 3-3. Overview of supporting systems and infrastructure. Element Comments Environmental Monitoring Additional environmental monitoring, such as reports on glycol use (used by airlines for de-icing) Lighting Systems/ Navaids Consider lighting systems, including navigational aids such as instrumented landing systems and windsock, required for safe operation Security Systems Components required to maintain security for safe operation, such as fences and gates Data Availability Quality and quantity of data available for a satisfactory evaluation of climate related vulnerabilities
3.1.3. Other Other elements considered include: • Emergency Procedures and Medevac • Wildlife • Future Development / Masterplan • Municipal Services (e.g., water, sewer and power)
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3.2. Performance Response Performance response factors were identified to assess the potential impact of climate change effects on the infrastructure components. The performance response categories selected for this assessment are summarised in Table 3-4.
Table 3-4. Performance response considerations. Performance Response Description Structural Design Conformity to the original structural design of the infrastructure and potential risk of failure. Functionality The ability to keep up the state of repair required to ensure a specified level of service of infrastructure within available resources. Serviceability The ability of infrastructure to fulfil its intended purpose. Watershed, Surface Water & The risk of impacting the original hydrology and water cycle in a Groundwater significant way Operations, Maintenance & The effort required to provide a specified level of service for Materials Performance infrastructure. Emergency Response The risk of interference with the use of infrastructure in the provision of emergency response services (incl. Medevac). Economic Considerations The financial impacts (both public and private) resulting from changes or complete loss in the functionality of infrastructure of interest. Policy Considerations Changes in methods used to design, construct, operate, or maintain the infrastructure. Social Effects Impacts on social and socioeconomic aspects resulting from changes or complete loss in the functionality of, or the operations and maintenance efforts associated with the infrastructure. Environmental Effects The environmental impacts resulting from changes in the functionality of, or the operations and maintenance efforts associated with the infrastructure.
3.3. Climate Baseline The climate baseline data used in the design of Cambridge Bay Airport is unavailable. Climate normals for the period from 1981-2010 for the Cambridge Bay A station show an average air temperature of -13.9ºC. Maximum air temperatures occur during July and minimum air temperatures occur during January. Annual precipitation amounts to 141.7 mm of precipitation, with 72.1 mm of rain and 80.2 cm of snow. An average wind speed of 19.6 km/h with a predominant wind direction of northwest was observed. Average air freezing index is 5661 degree-days and the average air thawing index is 636 degree- days.
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3.4. Climate Change Assumptions Environment Canada’s climate station at the Cambridge Bay Airport shows a historic trend of increasing air temperatures and precipitation over the 57-year climate record (1958-2015). Mean annual air temperatures have increased by an average of 0.6ºC per decade over the past 30 years. The warming has occurred mostly during the fall and winter, with spring and summer temperatures showing less of a trend. Average annual precipitation totals have been increasing, with the largest increases occurring during the summer and fall. Modest declines in precipitation are evident in the winter and spring. A detailed analysis of the historical climate record for Cambridge Bay Airport is provided in Appendix A. Also contained in the appendix is an overview of climate change projections for the Cambridge Bay area based on regional climate models developed by others. The following section summarizes the climate elements potentially impacting the vulnerability of the airport infrastructure (Table 3-5), the relevant historical climate trends (Table 3-6), and the projected climate changes for the Cambridge Bay area (Appendix A).
Table 3-5. Climate Effects and potential change factors and impacts. Climate Potential Change Affected Infrastructure and Potential Impacts Element Factor Air • Rate of change Ground temperatures are strongly influenced by air Temperature • Mean values temperatures. The depth of influence depends on the period (freezing / thawing degree-days), with daily temperatures • Extremes (high affecting the runway surface, seasonal temperatures summer/low affecting the top of the foundation soils and long-term winter) (annual, decadal) trends influencing ground temperatures at • Freezing and depth (typically 10 m depth and greater). Ground thawing indices temperature changes that can cause frost heaving or permafrost thaw may result in embankment instabilities through differential movements, shoulder rotation, or sloughing. The majority of infrastructure founded on permafrost soils is influenced by changes in seasonal and longer-term air temperature trends. Ground • Rate of change Similar effect to air temperature changes. In warm Temperature • Freezing and permafrost environments, long-term trends (rate of change) thawing indices in ground temperatures differ from changes in air temperature because of latent heat effects at the permafrost table. Frost • Freeze/thaw Frost is strongly related to air temperatures. However, cycles elements such as the runway surface or culverts can be structurally affected by changing number in frost cycles due to deformations associated with the volumetric changes when water freezes to ice and vice-versa. Freeze-thaw cycles can affect the runway friction and roughness increasing the required length for aircrafts to stop or result in limiting aircraft weights. It may further affect runway puddling and therefore require more maintenance.
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Climate Potential Change Affected Infrastructure and Potential Impacts Element Factor Rainfall • Frequency Rainfall affects the surface hydrology and, to a lesser degree, • Duration the ground thermal regime. Intense rain events may exceed the design flow capacities for culverts and ditches, resulting • Intensity in water ponding and flooding of infrastructure. Water that • Total accumulates to develop ponds could form a heat sink that annual/seasonal alters the geothermal regime. • Rain on snow Freezing rain is a significant hazard to aircraft as it may • Freezing rain reduce runway friction and requires additional aircraft de- icing efforts. Rain on snow events may cause floods and hazards. Snowfall • Frequency Snow storms reduce visibility and affect maintenance and • Duration operation of the airport. Furthermore, thick snow cover acts as a thermal insulator, preventing cold winter air • Total annual temperatures from penetrating the ground and resulting in • First/last snow day ground warming. On the other hand, reduced snow cover could result in ground cooling. Total annual snow accumulation may further influence drainage conditions and culvert capacities during freshet. Wind • Gusts Wind affects safe approaches for airplanes, i.e. main airport • Direction operations all year. • Seasonal It also influences the maintenance and operation of the airport by causing disruptions to flights, visibility issues, and wind-swept debris. Snow drifts may further affect ground thermal conditions across the road embankment by reducing the insulting snow cover on one side slope and thickening the layer on the other. Storms • Blizzards/White- Storms affect operation and maintenance of the airport Outs through disruption to flights, visibility issues, and potential • Ice storms damage to vital infrastructure. In northern communities, airport shutdowns may have major • Hail social and economic impacts since air traffic may be the only • Lightning/Electrical means of transportation and provides vital connections to storms other communities. Visibility • Fog Changes in weather effects to visibility such as fog, cloud • Cloud cover/solar cover, and cloud ceiling height can cause disruptions to radiation flights and other airport operation issues. • Cloud ceiling height
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Table 3-6. Historical climate trends, Cambridge Bay (1986-2015). Climate Element Best-Fit Linear Trends Air Temperature • Mean annual air temperature is increasing 0.6 °C per decade • Rate of warming is greatest in winter and fall • Extreme cold days occur most frequently from December to April and extreme warm days occur most often from June to August Freezing and • Freezing index decreasing by -212 degree-days per decade Thawing Indices • Thawing index increasing by 42 degree-days per decade Freeze/Thaw Cycles • Annual freeze/thaw cycles decreasing by -0.8 cycles per decade • Fall freeze/thaw cycles show no trend, spring freeze/thaw cycles are increasing Precipitation • Annual precipitation is increasing by 5.4 mm per decade • Precipitation increasing during summer and fall, with slight decreases in winter and spring • Heavy rainfall events occur most frequently during July and August Snow Depths • Snow depths show no clear trend First/Last Snow Day • First snow days are occurring later is the season • Last snow days show no statistically significant trend Wind • No statistically significant trend Note: Significant data gaps on separate snow and rainfall data, hence those could not be evaluated independently.
3.5. Changes in Climate Parameters Detailed description on climate change projections and assumptions used are provided in Appendix A. The climate change projections were estimated using the Canadian models CanESM2 and CanRCM4 in the RCP4.5 and RCP8.5 experiments, respectively2. For the Cambridge Bay area, all models show an increase in air temperature of 3 to 5ºC by 2045 compared to the 1986-2005 average daily air temperature. Projections from the Community Earth System Model (CESM) show the greatest temperature increases during the fall and winter, with smaller temperature increases in spring and summer. Depending on the scenario and the model, mean precipitation rates are expected to increase by 10 – 40% by 2045, which is consistent with the recent historical long-term trend. A level of confidence – High (H), Medium (M), Low (L) – was assigned to each parameter listed below, based on a combination of observed trends, projected trends, and observations from locals as discussed during the site visit in July 2015. The assignment is mainly based on data availability for climate model calibration and historic trends.
2 Canadian Centre for Climate Modelling and Analysis(CCCma): http://ec.gc.ca/ccmac-cccma/default.asp?lang=En&n=4596B3A2-1
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3.5.1. Air Temperature With regards to air temperatures, trends in the mean annual air temperatures as observed in recent history and projected in the near-future (i.e., next thirty years) are considered to not significantly affect airport infrastructure and operations. However, other parameters related to air temperatures are more significant for the assessment. Those are briefly discussed in Table 3-7.
Table 3-7. Climate parameters related to air temperatures. Parameter Comments and expected trends Confidence Maximum Air Increase in the maximum air temperature as well as an M Temperature increase in the frequency of extreme warm air temperatures Minimum Air Decrease (warming) in extreme cold air temperatures and M Temperature decrease in the occurrence of extreme cold air temperatures Freezing Index Decrease in degree days, i.e. warming in winter H Thawing Index Increase in degree days, i.e. warming in summer H Freeze – Thaw Cycles Increase in the number of freeze-thaw cycles per season M Heat Waves Increase in extended periods of warm air temperature L Cold Waves Decrease in extended periods of cold air temperature L
3.5.2. Frost The climate data available from Environment Canada do not provide sufficient evidence for an increasing trend in frost cycles. A low confidence for this trend is suggested.
3.5.3. Precipitation Climate parameters related to precipitation are listed in Table 3-8.
Table 3-8. Climate parameters related to precipitation. Parameter Comments and expected trends Confidence Rainfall Frequency More frequent rainfall events M Rainfall Duration Duration of rainfall events increase M Rainfall Intensity / Storms The intensity of the rainfall increases M Rainfall in Fall Increased number of rain days in fall L Freezing Rain Increase in days of freezing rain M Rain on Snow Increase in rain on snow events during the winter M months Total Snowfall Decrease in total amount of snow during the winter L Snowfall Duration Duration of snowfall events decrease M Snowfall Frequency Less frequent snowfall events M
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First Snow Day Snow starts staying on the ground later in the year L Last Snow Day Snow has completely thawed earlier in the year L Blizzards / White-outs Increase in the number of blizzards L Ice Storms Increase in the number of ice storms L Hail Increase in the number of hail events L
3.5.4. Others Additional climate parameters that are included in the assessment are summarized inTable 3-9.
Table 3-9. Other climate parameters. Parameter Comments and expected trends Confidence Wind Gusts Increase in the velocity (strength) of wind gusts L Wind Direction Change in predominant wind directions L Wind in Winter Change in wind regimes (strength and direction) during M the winter months. Winter conditions are separated from the rest of the year as it impacts snow drift Ground Freezing Index Decrease in degree days, i.e. ground temperature H increase in winter Ground Thawing Index Increase in degree days, i.e. ground temperature H increase in summer Cloud Cover Decrease in cloud cover and increase in solar radiation L Cloud Ceiling Height Decrease in cloud ceiling height L Fog / Visibility Increase in days with fog and decrease in visibility M Lightning / Electrical Storms Increase in lightning activity (thunderstorms) and L electrical storms Flooding The airport is located at an elevation where flooding will L likely not affect the infrastructure. Forest Fires Airport infrastructure is located on tundra such that - forest fires will not affect the physical infrastructure.
3.5.5. Climate Variability The annual changes in varisou climate parameters seems to have increased and based on input from locals, seasonal weather has become less predictable. Therefore, it seems that the variability in the climate parameters listed above has increased (Medium Confidence).
3.5.6. IDF Curves The online IDF CC Tool, developed at the University of Western Ontario, was used to assess IDF climate change projections. Results provided in Appendix A show that for the RCP4.5 scenario, the historical IDF curve falls within the range of projected IDF, and for the RCP8.5 scenario, the historical IDF curve falls at the lower bound or below the predictions.
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3.5.7. Perceived Sensitivities to Climate Change Observations from a reconnaissance visit and research program which was part of the Nunavut Climate Change Partnership (NCCP) were presented by Smith and Forbes (2014). Seven main sensitivities were identified: 1. In the specific context of climate warming, landscape hazards in Cambridge Bay appear to pose a low risk. 2. While increased open water and wave action brought on by reductions in summer sea ice create a significant threat to coastal stability in many Arctic communities, the protected setting of the Cambridge Bay harbour minimizes this risk. Houses, cabins and roads located near the seashore northwest of the airport and south of Tikiraaryuaq do potentially face increased threat of storm surge, wave action and ice ride-up or pile-up. 3. Thermokarst ponds, ice wedges and ground subsidence in areas of surface-water ponding demonstrate that varying quantities of excess ground ice occur within surficial deposits in the Cambridge Bay area. Excess ground ice represents a potential hazard to infrastructure stability. 4. The coarse-grained, gravel-rich materials used to construct roads and building pads in the Cambridge Bay area are an asset to the region’s infrastructure stability. 5. The use of gravel building pads and integrative spaceframe foundations for new housing multiplexes appears well-adapted to environmental conditions in Cambridge Bay. In some cases, pad thicknesses were noted to vary between adjacent buildings, including sites where thicknesses appeared insufficient to ensure that foundations were raised above seasonal water ponding. 6. Urban hydrology will continue to be an area of focus and concern in reflection of present environmental conditions, as well as those that may occur as a result of future climate change. Structural measures may be required, particularly in light of potentially extreme summer rainfall events or early season rain-on-snow events. 7. Snow drifting is a recognized development issue in Cambridge Bay. Changes in snowfall amounts and storm trajectories projected to occur under various climate change scenarios may also require a reassessment of existing infrastructure adaptations.
3.6. Historical Climate Extremes Typically, it is not the overall trend or the average conditions that influences infrastructure performance, but the extreme climate event. The historical trends and potential changes of these events, as presented in Appendix A, can be summarized as follows: • Decrease in the occurrence of extreme cold days (≤ -35 °C), no clear trend in extreme warm days (≥ 25 °C). • The maximum number of intense rainfall days (≥ 10 cm) occurs during the month of July. No clear trend in occurrence is observed. • Heavy snowfall days (≥ 10 cm), most frequently occurs during the month of May. • Freezing precipitation days most frequently occur during the months of May and October.
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• No trend data for rain on snow events are available. These events most frequently occur in June. • The most “strong wind days” occur during October. No clear trend has been noted.
3.7. Time Frame A fixed 30 year time frame (2045) was chosen for this analysis (see Section 2.5).
3.8. Geography and Permafrost Geography considerations are identified in Step 1 (see Section 2.3.1). Permafrost conditions are identified in Section 2.3.
3.9. Jurisdictional Considerations Agencies and departments at the federal, provincial and municipal levels have jurisdictional control and influence on various elements / sections of the airport. These are identified in Step 1 (see Section 2.6).
3.10. Potential Changes that May Affect the Infrastructure In addition to the climate-related effects, the runway, taxiways, and aprons are subjected to other loads that may affect its performance (Table 3-10).
Table 3-10. Potential changes that may affect the airport infrastructure. Change Comments Travel Frequency As number and frequency of flights to the airport increases more wear and tear of infrastructure components may occur. Aircraft Type Changes in the type of aircraft serving the airport, both civil and military, may impact the wear and tear on infrastructure components. Aging Regular aging of the infrastructure is ongoing and may affect performance.
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4.0 STEP 3 – RISK ASSESSMENT The vulnerability assessment component of the Protocol identifies where an interaction, relationship or direct dependency between an infrastructure component and a climate event exists. By ranking the probability of the interaction occurring (P) and the severity resulting from the interaction (S), a risk value (R) is calculated. The determination of the probability and severity factors are based on experience and professional judgment. Different personnel are involved in this process to provide an objective rating. The Protocol specifies that a risk assessment workshop be held with local management and operations staff. Since no such workshop was held, this step was not carried out as per the Protocol. Following then is a description of the risk assessment procedure, as per the Protocol. The interactions between the performance response of the infrastructure components and climate events described below have been developed based on BGC’s experience from vulnerability assessments of other linear infrastructure constructed on permafrost, combined with brief discussions with local airport staff. To properly follow the steps of the Protocol, these interactions should be discussed to confirm their relevance and the appropriateness of the assigned probability and severity factors, described below. The Protocol outlines that the risk evaluation be undertaken by following the steps below: 1. Determine which performance factors are applicable to each infrastructure component; 2. Indicate in the matrix if there is a relationship between each infrastructure component and the climate event (Y/N); 3. For each climate event, assign a probability scale factor P (0-7); 4. For each climate event – infrastructure component relationship, assign a severity scale factor S (0-7); 5. Calculate the risk of the infrastructure component/climate event relationship as the product of probability and severity: R = P x S. The final risk value determines future actions, as summarized in Table 4-1.
Table 4-1. Risk tolerance thresholds used for this assessment adapted from the Protocol (Canadian Council of Professional Engineers, 2012). Risk Range Threshold Response <15 Low Risk No immediate action necessary 15-25 Medium-Low Risk Action may be required 25-35 Medium-High Risk >35 High Risk Immediate action required
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4.1. Performance Response of the Infrastructure Component The performance response factors described in Section 3.2 should be assessed qualitatively with respect to their potential impact on an infrastructure component, as summarized in Table 4-2. A table summarizing these interactions is also included in the proposed risk matrix (Appendix B).
Table 4-2. Performance response prioritization methodology. Performance Response ( if yes)
Material
Infrastructure Component
ations, Maintenance & Maintenance ations, Structural Design Structural Functionality Serviceability & Groundwater Water Surface Watershed, Oper Performance Response Emergency Considerations Economic Considerations Policy SocialEffects Effects Environmental Physical Infrastructure Runway Taxiways Aprons Drainage System Access and Service Roads Heterogeneity in Natural Foundation/Permafrost
Supporting Infrastructure O & M Personnel Snow Clearing Resurfacing Winter Flight Operation Summer Flight Operation Summer Maintenance Winter Maintenance
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Performance Response ( if yes)
Material
Infrastructure Component
ations, Maintenance & Maintenance ations, Structural Design Structural Functionality Serviceability & Groundwater Water Surface Watershed, Oper Performance Response Emergency Considerations Economic Considerations Policy SocialEffects Effects Environmental Lighting Systems Surface Markings Environmental Monitoring Navaids Vegetation Security Structures Data Availability
Others Emergency Procedures and Medevac Wildlife Future Developments/Master Plan Municipal Services
4.2. Potential Climate Events The risk assessment uses a screening tool to identify infrastructure components that are critically affected by climate change. Therefore, only climate events that affect the performance response of one or more infrastructure components are considered. The following 32 climate events are recommended for consideration: • Maximum Air Temperature • Snowfall Frequency • Minimum Air Temperature • First Snow Day • Air Freezing Index • Last Snow Day
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• Air Thawing Index • Blizzards/White-outs • Freeze – Thaw Cycles • Ice Storms • Heat Waves • Hail • Cold Waves • Wind Gusts • Frost • Wind Direction • Rainfall Frequency • Wind in Winter • Rainfall Duration • Ground Freezing Index • Rainfall Intensity (Rain Storms) • Ground Thawing Index • Rainfall in the Fall • Cloud Cover/Solar Radiation • Freezing Rain • Cloud Ceiling Height • Rain on Snow • Fog/Visibility • Total Snowfall • Lightning/Electrical Storms • Snowfall Duration • Climate Variability
4.3. Probability Estimation The Protocol defines the probability scale factor, P, as the probability of an infrastructure component to lose its functionality or have its performance adversely affected if it is exposed to a certain climatic condition. Two methods are proposed in the Protocol to rank this probability, as shown in Figure 4-1. For this study, Method A is recommended as the most appropriate because there is insufficient data to conduct a quantitative assessment.
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Figure 4-1. Methods to estimate the probability scale factors according to Canadian Council of Professional Engineers (2012). Method A is recommended for this assessment.
4.4. Severity Estimation The Protocol also defines the severity scale factor, S, to express the severity of the consequences of loss in performance or functionality of an infrastructure component. The Protocol provides two methods for selecting the severity (see Figure 4-2). Method E, a qualitative assessment, is recommended for reasons similar to the selection of the probability scale factor.
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Figure 4-2. Methods to estimate the severity scale factors according to Canadian Council of Professional Engineers (2012). Method E is recommended for this assessment.
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5.0 DISCUSSION AND RECOMMENDATIONS
5.1. Preamble Step 4 of the Protocol normally consists of an engineering analysis of combinations of medium to high risk in order to evaluate if the assigned risk is reasonable (Figure 1-1). This step is then followed by listing specific recommendations for all combinations. These recommendations generally fall into five major categories: • remedial action is required to upgrade the infrastructure; • management action is required to account for changes in the infrastructure capacity; • continue to monitor performance of infrastructure and re-evaluate at a later time; • no further action is required; and/or • there are gaps in data availability or data quality that require further work. However, since no detailed risk assessment was carried out, such specific recommendations could not be provided for Cambridge Bay Airport. This section therefore provides a discussion and recommendations based solely on BGC’s understanding of the climate and infrastructure conditions at Cambridge Bay Airport.
5.2. Limitations Future trends of air temperature change can be reasonably projected, however, it is more challenging to project changes in the intensity and duration of precipitation events, let alone project for second and third order climate events, such as frost, wind, ground and water temperatures or visibility. Therefore, there are large uncertainties associated with such projections. For example, the limitations for rainfall projections should be noted as stated in the Climate Data Analysis (Appendix A): “Current climate models are unable to predict rainfall intensity at the short durations (e.g., <24 hours) required to generate IDF curves. Consequently, modeled rainfall projections cannot be used directly to generate projected IDF curves for future conditions.” While these limitations are considered acceptable for the purposes of this study, they must be considered in the development of recommendations.
5.3. Discussion Based on future projections and the nature of the airport infrastructure, the five climate events likely associated with higher risk values are: • Rainfall, including IDF; • Visibility; • Frost; • Ground Thawing Index; and • Climate Variability.
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Historic trends and climate projections both provide indications for changes in rainfall patterns in terms of timing, frequencies, durations, and intensities. For example, the airport’s drainage system may not be adequate for future rainfall patterns and adaptation measures may be required. In addition, rainfall can cause thermal as well as mechanical erosion of the gravel runway, its shoulders, taxiways and aprons. Ponding water may act as a heat sink and contribute to permafrost degradation and thaw settlements, or it can contribute to frost heave and related damage. If ponding water occurs on the runway, taxiways or the apron it can also affect the safety of the airplane and affect operations. Poor visibility due to fog, low cloud ceiling or white outs is the primary natural cause of flight cancelations and delays. Very little data exist on the recent changes in visibility and how it may change in the future. However, increased moisture in the air and longer open water seasons may result in increased number of hours with poor visibility that may affect operations and maintenance of the airport. The changes in moisture, together with potential changes in the daily variability of air temperatures may increase days where frost affects the runway, taxiway and aprons. Frost can affect runway friction and may damage the surface due to frost action. This would require increased maintenance and repair work in order to minimize delays in takeoffs and landings. However, available data do not provide sufficient evidence of changes in frost or freeze-thaw cycles. An increase in ground temperatures, and associated ground thawing index, is anticipated, based on historic trends and projected increase in air temperatures. A higher air thawing index results in active layer thickening, permafrost degradation, and potentially thaw settlements. Heterogeneity in the permafrost foundation could result in differential settlements that will require increased maintenance effort. The changes in ground temperatures are expected to be slow. However if ice rich zones, such as ice wedges, exist under an infrastructure, which is possible, even though the overall probability of ice wedges to exist in the airport area is low, a potential for developing a sinkhole prevails if the engineered embankment structure is able to bridge a thawed ice wedge. Finally, the variability in climate is expected to change making long-term predictions more challenging, with the characteristics (e.g. dry, cold) of the seasons becoming more volatile. This can affect construction seasons and general airport maintenance scheduling.
5.4. Recommendations The vulnerability assessment has not been completed as per the Protocol and therefore no immediate engineering action is recommended. As an initial step, it is recommended to complete the climate change vulnerability assessment by having the risk workshop with participants from airport management, maintenance, operators, users, local climate experts and other interested parties. The workshop will allow to quantify the risk, which forms the basis for future analysis and assessments.
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However, based on the work carried out up to now, it is strongly recommended that a monitoring system be developed that is tailored towards identifying trends that may be related to climate change. Sufficient quantitative data must be available for making informed decisions. In addition to the assessing data from the automatic weather station operated by Environment Canada, it is specifically recommended to: • Evaluate the capacity of drainage systems to assess the resiliency of culverts and ditches against higher flows, and measure runoff and changes in surface water bodies to evaluate changes in the surface hydrology; • Systematically collect information on the visibility (e.g., fog & cloud ceiling) in the form of detailed logbook on the weather conditions at the time and the characteristics of the limited visibility event. Such records are used in identifying potential trends that help in deciding if upgrades in the current instrumentation is required; • Collect data on frost formation, such as climate parameters, timing, location and extent to assess conditions during which and to what degree frost related challenges occur; • Review frost management procedures to identify if changes in current operation and maintenance practices need to be implemented; • Update or develop an asset management system including the definition of current service lives of the various infrastructures based on current understanding of traffic loads and climate parameters. • Monitor local snow accumulation, including spatial (re-)distribution and note limitations to operations to assess current snow management plans and plan future snow management requirements, such as snow fences or additional equipment; • Measure ground temperatures at various locations across the airport property using thermistor strings and automated data loggers to monitor changes in the ground freezing and thawing indexes, including the spatial variability, and identify how they relate to the known changes in air temperature; • Document in a logbook / database climate-related flight delays/cancellations to identify if and what climate events triggered the delay / cancellation, and to recognise potential trends; • Document in logbook / database maintenance and repair activities, including date, location, type and extent, so that the infrastructure performance can be related to climate trends and events; and • Carry out an initial climate change vulnerability assessment and re-evaluate it every five years, as new baseline data, infrastructure performance information, and improved climate models become available. Based on our understanding of the current airport infrastructure performance and projected climate change, no immediate remedial action necessitating significant engineering effort is required.
5.5. Master Plan 2010 The Master Plan 2010 for Cambridge Bay Airport (LPS, 2010) includes a runway expansion to the northwest, a Runway End Safety Area (RESA) beyond the end of the runway, an expanded
Cambridge Bay Climate Vulnerability Report.docx Page 39 BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004 runway graded area, an expanded apron, two new taxiways (C & D), and modified high intensity approach lightning. Based on the current understanding of the local permafrost conditions and the projected climate trends it is recommended that: • Potentially ice rich zones, i.e., ice wedges that cannot be ruled out and areas susceptible to thermokarst are identified and appropriate measures implemented; • The design of the drainage structures accounts for potential changes in precipitation regimes (i.e., drainage capacity) and minimizes degradation of thaw-sensitive permafrost, such as the thermokarst ponds shown in Figure 2-5; • Fill structures that are designed to preserve the permafrost foundation are adequately sized considering projected increases in air temperature due to long-term climate trends and extreme warm years, particularly in the area of the apron expansion and Taxiway C; and • Adequate infrastructure performance monitoring system, as outlined in Section 5.4, is implemented.
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6.0 CONCLUSIONS A climate change vulnerability assessment was initiated for Cambridge Bay Airport located in the continuous permafrost zone of Nunavut. The initial assessment followed three out of five steps of a standardized protocol prepared by the Public Infrastructure Engineering Vulnerability Committee (PIEVC). Within the Protocol, the 30-year projected climate change trends for the Cambridge Bay region, which are based on climate modelling results and historic data, were evaluated. Key trends are: • mean annual air temperature is increasing at about 0.6 °C per decade with warming rates greatest in winter and fall; • the number of annual freeze/thaw cycles is decreasing by less than one cycle per decade; • annual rainfall is increasing by 5 mm per decade with the maximum number of intense rainfall days occurring in the months of July and August; • first snow days are occurring later in the season whereas last snow days show no statistically significant trend; • no statistically significant trend was identified in annual total snowfall; and • no statistically significant trend was identified for changes in wind direction and intensity. In total, 24 infrastructure components and 32 climate events were identified that result in 768 potential infrastructure - climate event combinations. Those combinations would need to be discussed in detail amongst various parties to identify high and medium rick combinations. Based on the data available and our understanding of the current airport infrastructure performance, no immediate engineering action is required for Cambridge Bay Airport. The assessment suggests that five climate events -- rainfall, visibility, frost, ground thawing index, and climate variability -- are the main climate events that may affect future airport operations and infrastructure performance. However, there are currently insufficient detailed data available and the occurrence of these climate events is difficult to project with confidence. In addition, current environmental and maintenance baseline data are inadequate for carrying out a detailed engineering assessment. Therefore, it is recommended to collect such baseline data in a systematic manner to provide input for making informed decisions for allocating resources and for designing mitigation and adaptation strategies if those were needed. Specifically, this includes: • Evaluate the capacity of drainage systems to assess the resiliency of culverts and ditches against higher flows, and measure runoff and changes in surface water bodies; • Systematically collect information on the visibility in the form of detailed logbook /database on the weather conditions at the time and the characteristics of the limited visibility event; • Collect data on frost formation, such as climate parameters, timing, location and extent; • Review frost management procedures; • Update or develop an asset management system, including an evaluation of current infrastructure service lives; • Monitor local snow accumulation, including spatial (re-)distribution and note limitations to operations;
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• Automated measurement of ground temperatures at various locations across the airport property; • Document in a logbook / database climate-related flight delays/cancellations, as well as maintenance and repair activities, including date, location, type and extent; and • Carry out an initial climate change vulnerability assessment with several stakeholders that include the airport operators, the owners and users of the airport, and re-evaluate it every five years, as new baseline data, infrastructure performance information, and improved climate models become available. The changing climate will likely result in increased maintenance and repair efforts that must be considered when evaluating current operation practices, and for which resources must be provided.
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7.0 CLOSURE We trust the above satisfies your requirements at this time. Should you have any questions or comments, please do not hesitate to contact us.
Yours sincerely,
BGC ENGINEERING INC. per:
Midori Telles-Langdon, B.A.Sc., E.I.T., G.I.T. Lukas Arenson, Dr.Sc.Techn.ETH, P.Eng. Junior Geological Engineer Senior Geotechnical Engineer
Reviewed by: Jack T.C. Seto, M.Sc., P.Eng., P.E. Principal Geotechnical Engineer
LUA/JTCS/gc
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REFERENCES
3vGeomatics Inc. 2011. Nunavut Terrain and Soil Analysis. Report submitted to Government of Nunavut, March 2011. Arenson, L.U., Colgan, W. and Marshall, H.P. 2014. Physical, Mechanical and Thermal Properties of Snow, Ice and Permafrost. In Snow and Ice-Related Hazards, Risks and Disasters. Haeberli W. and Whiteman C. (Editors) Elsevier Inc., ISBN: 978-0-12-394849-6: 35–75. Biggar, K.W. and Sego, D.C. 1993. The strength and deformation behaviour of model adfreeze and grouted piles in saline frozen soils, Canadian Geotechnical Journal, 30: 319-337. Canadian Council of Professional Engineers. 2012. PIEVC Engineering Protocol For Infrastructure Vulnerability Assessment and Adaptation to a Changing Climate, Revision PG-10. Engineers Canada, Ottawa, ON. EBA Engineering Consultants, Ltd. 2012. Phase II/III Environmental Site Assessment at Airport Shoreline in Cambridge Bay, NU. Report prepared for Public Works and Government Services Canada, January 2012. Environment Canada. 2016. Canadian Climate Normals 1981-2010 Station Data, Cambridge Bay A [online]. Available from http://climate.weather.gc.ca/climate_normals/results_1981_2010_e.html?stnID=1786 [accessed March 15, 2016]. Harris, S.A., 1986. Permafrost distribution, zonation and stability along the eastern ranges of the Cordillera of North America. Arctic, 39: 29-38. Hivon, E.G. and Sego, D.C. 1993. Distribution of saline permafrost in the Northwest Territories, Canada, Canadian Geotechnical Journal, 30, 506-514. Instanes A., Anisimov, O., Brigham, l., Goering, G., Khrustalev, L.N., Ladanyi, B., and Larsen, J.O. 2005. Infrastructure: Buildings, Support Systems, and Industrial Facilities. Arctic Climate Impact Assessment. Cambridge University Press, Chapter 16: 907-944. Lemmen, D.S., Warren, F.J., James, T.S., and Mercer Clarke, C.S.L. 2016. Canada’s Marine Coasts in a Changing Climate. Ottawa, ON. 280p. LPS Aviation. 2014. Nunavut Airports 20 Year Infrastructure Needs Assessment, 2014-2034. Report prepared for Government of Nunavut, April 17, 2014. LPS Aviation. 2010. Master Plan 2010 Cambridge Bay Airport. Report prepared for Government of Nunavut, June 24, 2010. National Research Council Canada (NRCC). 1988. Glossary of Permafrost and Related Ground- Ice Terms. Technical Memorandum 142.
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Natural Resources Canada. 1995. Canada Permafrost [permafrost map]. Scale 1:7,500,000. The National Atlas of Canada, 5th Ed. Available from http://www.nrcan.gc.ca/earth- sciences/geography/atlas-canada/selected-thematic-maps/16886#physicalgeography [accessed January 19, 2016]. Smith, I.R., and Forbes, D.L. 2014. Reconnaissance assessment of landscape hazards and potential impacts of future climate change in Cambridge Bay, western Nunavut. Summary of Activities 2013, Canada-Nunavut Geoscience Office: 159-170. Statistics Canada. 2016. Monthly aircraft movements, by class of operation and type of operation, airports without air traffic control towers, March 10, 2016 [online]. Available from http://www5.statcan.gc.ca/cansim/a47 [accessed March 15, 2016]. WorleyParsons. 2013. Cambridge Bay Airport Expansion – Geotechnical Investigation. Report prepared for the Government of Nunavut, January 2013.
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PHOTOGRAPHS
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Photo 1. (July 26, 2015).
End of runway 31-31T looking northeast.
Photo 2. (July 26, 2015).
End of runway looking along high intensity approach lightning line.
Photo 3. (July 26, 2015).
Lightning end of runway 13-31T (east end)
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Photo 4. (July 26, 2015).
End of runway 31-31T looking northwest along north shoulder.
.
Photo 5. (July 26, 2015).
Looking along Taxiway B towards DND building and Apron II.
Photo 6. (July 26, 2015).
Runway expansion on the south side, looking northwest.
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Photo 7. (July 26, 2015).
Embankment fill opposite of taxiway A, looking southwest.
Photo 8. (July 26, 2015).
Ditch along the south edge of the runway looking northwest.
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Photo 9. (July 26, 2015).
Looking south from runway towards DND building.
Photo 10. (July 26, 2015).
Looking from northwest end along northern shoulder.
Photo 11. (July 26, 2015).
Water ponding along north side of the runway at the northwest end.
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Photo 12. (July 26, 2015).
Runway 13-31T, looking from northwest end to the southeast.
Photo 13. (July 26, 2015).
Access road on the southwest end, looking north. Just to the left is the location of future new Taxiway C.
Photo 14. (July 26, 2015).
Environment Canada automatic weather station.
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Photo 15. (July 27, 2015).
Apron I, looking west towards runway.
Photo 16. (July 26, 2015).
Potholes in the hamlet of Cambridge Bay.
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APPENIDX A CLIMATE INFORMATION ANALYSIS
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A.1. INTRODUCTION As part of BGC Engineering Inc. (BGC)’s vulnerability assessment of the Cambridge Bay Airport to future climate change, the current state of knowledge of climate change in the Canadian North was reviewed, the historical climate record from Environment Canada’s meteorological station at Cambridge Bay Airport compiled and assessed, and publicly- available climate change projections for the Cambridge Bay region were collected. Very little information is available on ground temperatures and long-term trends in permafrost in the Arctic. Therefore, some findings are included in this appendix that are from measurements located at significant distances from Cambridge Bay, but are still considered relevant for the assessment. This appendix summarizes the main findings. A.2. EVIDENCE OF CLIMATE CHANGE IN THE ARCTIC In a phenomenon known as Arctic amplification, Arctic temperatures have increased at a rate nearly double the global average. Warmer temperatures have affected sea ice and snow cover to an extent not previously predicted by climate models (Cohen et al., 2014). The following sections summarize the observed changes in air temperature and precipitation and their significance to the cryosphere in the Canadian Arctic, with specific emphasis on recent work relevant to the project area.
A.2.1. Air Temperature The following observations have been reported with respect to temperature trends in the continental Canadian Arctic for the period since the 1950s (Zhang et al., 2000; Bonsal et al., 2001; McBean et al., 2005; Prowse et al., 2009; Cohen et al., 2014): • the warmest temperatures in the Arctic on record have occurred since 2005; • northern hemisphere high latitudes have experienced temperature increases at twice the rate of lower latitudes; • Arctic amplification is strongest in the fall and winter months; and • warming during the past 150 years has been unprecedented since the onset of the current interglacial period. Overall, arctic temperatures have increased at unprecedented rates and to unprecedented levels since the mid-20th century (IPCC, 2013). This is in line with predictions from global climate circulation models.
A.2.2. Freezing and Thawing Index The air freezing index (AFI) and air thawing index (ATI) are two climate parameters widely used to quantify the “severity” of a winter or summer with respect to freezing or thawing effects on pavements (Doré and Zubeck, 2008). It is also a useful indicator of air temperatures over a season. The freezing index is defined as the number of negative degree days between the highest and lowest points on a curve of cumulative degree days versus time. The thawing index is the
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number of degree days between the minimum in the spring and the maximum the next autumn. Since ground surface temperatures are generally not available for most locations, air temperatures can be used as a surrogate. Work by Frauenfeld et al. (2007) showed that in recent decades, no significant changes in freezing and thawing index were observed in Russian permafrost regions. However, seasonally frozen ground areas were found to be experiencing significant warming trends. Over North America, including the Canadian and Alaskan permafrost regions, a decrease in the freezing index has been observed. Coastal areas and eastern Canada have experienced significant increases in the thawing index. The International Arctic Science Committee (2009) described projected changes in freezing and thawing indices calculated using output from the Arctic Climate Impact Assessment (ACIA)-designated climate models. An analysis for the community of Coppermine (Kugluktuk), Nunavut, showed that the 30-year mean AFI is projected to decrease from approximately 4850 degree-days in 1960 to 3850 degree-days in 2100. This represents an average increase in winter (October–March) temperatures of approximately 5 to 6°C. The 30-year mean ATI was projected to increase from approximately 720 degree-days in 1960 to 1430 degree-days in 2100, representing an increase in average summer (April–September) temperatures of approximately 4ºC. Instanes and Mjureke (2005) analyzed the effects of these changes at an airport at Svalbard, Norway using observed air temperature data from 1930 to 2000 and future air temperature projections. Their work suggested that the average thaw depth is projected to increase by as much as 50 percent between 2000 and 2050 and that ground temperatures at 2 m depth are projected to increase by 4ºC over this same period. Even at 40 m depth, ground temperatures were projected to increase by approximately 2ºC by 2050. Mills et al. (2009) reported that over the next fifty years, low-temperature pavement cracking will become less problematic, structures will freeze later and thaw earlier with correspondingly shorter durations in the freezing season. However, higher extreme in-service pavement temperatures will increase the potential for rutting, which will lead to earlier maintenance, rehabilitation and reconstruction in the design life of the paved surfaces.
A.2.3. Precipitation With respect to precipitation, the following observations have been made for the period of 1948 to 2005 (Mekis and Hogg, 1999; Zhang et al., 2001b, Prowse et al., 2009): • annual precipitation totals have increased throughout northern Canada, with the largest increases observed in the Arctic Tundra (+25%) and Arctic Mountain (+16%); • precipitation changes occurred most notably during the fall, winter and spring; • heavy precipitation events increased through the period of record; and • decadal increase in the frequency of heavy snowfall events occurred in northern Canada.
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Brown (2000) reported that snow cover extent has significantly decreased over most of Canada, especially during late-winter and early-spring. This was found to also influence the timing of snowmelt and freshwater ice breakup (Lacroix et al., 2005; Duguay et al., 2006).
A.2.4. Permafrost Temperatures and Active Layer Thickness Recent warming of permafrost has been observed across the Canadian permafrost region, although the magnitude and rate of change has varied, depending on the region. In northern Alaska, permafrost temperature increases of up to 3ºC have been observed in from the early 1980s to the mid-2000s. Permafrost extents in the near surface are projected to decrease by at least 37% in this region by the end of this century (IPCC, 2013). During the International Polar Year (2007-2008), a comprehensive permafrost temperature monitoring network was initiated. Data were presented in Smith et al. (2010) and Romanovsky et al. (2010). The data are now available from the Global Terrestrial Network for Permafrost, GTN-P (http://gtnpdatabase.org) that recently established the new, dynamic database (Biskaborn et al., 2015). Within the northern hemisphere polar region, ground temperatures are currently being measured in about 575 boreholes in North America, the Nordic region and Russia. However, nether Cambridge Bay nor any other site on Victoria Island has data included in the GTN-P and therefore the conclusions are not site specific, but address general trends for the Arctic. The measurements show that in the discontinuous permafrost zone, permafrost temperatures fall within a narrow range, with the mean annual ground temperature (MAGT) at most sites being warmer than -2°C. A greater range in MAGT is present within the continuous permafrost zone, from above -1°C at some locations to as low as -15°C. Permafrost temperature warming rates are much smaller for permafrost already at temperatures close to the melting point compared with colder permafrost, especially for ice- rich permafrost, where latent heat effects dominate the ground thermal regime (Smith et al., 2010; Ednie and Smith, 2015). Colder permafrost sites are warming more rapidly. A.3. ANALYSIS OF HISTORICAL CLIMATIC DATA FOR CAMBRIDGE BAY AIRPORT Historical climate data for the period from 1958-2013 was obtained from Environment Canada’s Cambridge Bay climate station, Cambridge Bay A, located at the Cambridge Bay Airport (WMO Identifier 71925, TC ID YCB). The climate station is located at 69º06’29” N and 105º08’18” W at an elevation of 31.1 m above sea level. Additional data for 2015 was obtained from the nearby Cambridge Bay GSN station (WMO Identifier 71288), located at 69º06’29” N and 105º08’18” W at an elevation of 18.7 m above sea level. The 58 year (1958 to 2015) climate record was analyzed with respect to changes in temperature and precipitation. The reference climate period used is the thirty-year climate normal period from 1981 to 2010. Recent long-term trends have been evaluated based on the thirty-year period of 1986 to 2015.
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A.3.1. Data Gaps Of the data compiled from Environment Canada, any year missing more than 5% (18 days) of the daily data values was excluded from calculations of the trend lines. Years missing 5-20% of the daily values are shown in red for qualitative comparison only. Years missing more than 20% of the daily values have been excluded from the figures. Figure A-1 shows the data availability for temperature, precipitation, rainfall, snowfall, snow on ground, and wind data. Wind
Snow on Ground
Snowfall
Rainfall
Precipitation
Temperature 2016 1998 2000 2002 2004 1986 2006 1988 2008 1990 2010 1992 2012 1994 2014 1996 1978 1960 1980 1962 1982 1964 1984 1966 1968 1970 1972 1974 1976 1958 Year Figure A-1. Cambridge Bay climate data availability.
A.3.2. Air Temperature
A.3.2.1. Mean Annual Air Temperature (MAAT) Figure A-2 (see attached Figures section) shows the mean, maximum and minimum annual air temperatures for the period of record. Figure A-3 compares the annual deviations in mean annual air temperature from the reference mean (averaged from 1958 to 1987). From these two figures, the following observations have been drawn: • Annual air temperatures have been steadily increasing over the past 30 years at an average rate of 0.6ºC/decade. • Temperatures are rising more during the fall and winter than during the spring and summer. • The majority of deviations from the mean annual temperature has been positive since the 1990s in comparison to the reference period, with the exception of 2004. • Temperature changes are significantly related to the Pacific Decadal Oscillation (PDO) Index with positive PDO indices being correlated to positive temperature anomalies and negative PDO indices correlated with negative temperature anomalies. Over the past decade, this correlation has waned, perhaps explaining the increasing dominance of other climate-forcing mechanisms (see Figure A-3).
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A.3.2.2. Maximum and Minimum Annual Air Temperatures As shown in Figure A-2, the minimum annual air temperatures have been increasing at an average rate of 0.8ºC/decade, while the maximum annual air temperatures have been decreasing at a rate of -0.7ºC/decade.
A.3.2.3. Seasonal Air Temperatures Figure A-4 shows the mean and seasonal yearly air temperatures for the period of record. Table A-1 summarizes the average annual and seasonal air temperature trends over the past thirty years (1986 to 2015).
Table A-1. Seasonal Air Temperature Trends from 1986 to 2015, Cambridge Bay Airport. Period Best-Fit Trend in Mean Annual Air Temperature (ºC/decade)
Annual 0.6
Winter (December to February) 0.8
Spring (March to May) 0.3
Summer (June to August) 0.5
Fall (September to November) 1.3
A.3.2.4. Freezing and Thawing Indices Figure A-5 presents the historical mean annual air temperature, freezing index and thawing index. The following observations have been drawn from this figure, acknowledging large inter- annual variability: • The general long-term trend is of decreasing freezing index and increasing thawing index, reflecting the long-term warming trend. • Over the past thirty years, the freezing index has declined at an average rate of -212 degree-days/decade and the thawing index has increased at an average rate of 42 degree-days/decade. In other words, subfreezing temperatures have been warming at a greater rate than above-freezing temperatures, reflecting the seasonal trends described in Section A.3.2.3.
A.3.2.5. Freeze-Thaw Cycles Premature deterioration of pavements is related to high frequencies of freeze-thaw cycles, particularly where subgrades are composed of fine-grained, saturated material. In permafrost areas, pavement structures stay strong throughout the winter because the subgrade remains frozen until spring. However, milder winters, with more freeze-thaw cycles, would accelerate road deterioration and increase maintenance costs. The historical air temperature record was examined to determine historical trends for the occurrence of freeze-thaw cycles. For this analysis, a freeze/thaw cycle was defined as a day
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where the maximum temperature exceeded 0ºC and the minimum temperature was less than -1ºC. The historical occurrence of freeze-thaw cycles at Cambridge Bay Airport is shown in Figure A-6. From this figure, the following observations have been drawn: • Annually, the number of freeze/thaw cycles are decreasing by -0.8 cycles per decade. • Fall freeze/thaw cycles show no trend overall, and spring freeze/thaw cycles have been increasing by 1.1 cycles/decade.
A.3.3. Precipitation
A.3.3.1. Precipitation Totals Figure A-7 presents the historical annual and seasonal precipitation records. Figure A-8 presents the historical annual precipitation, rainfall, and snowfall records. Figure A-9 shows the count of days with precipitation, rainfall, and snowfall. Table A-2 summarizes the average annual and seasonal precipitation trends over the past thirty years.
Table A-2. Seasonal precipitation trends from 1986 to 2015, Cambridge Bay Airport. Period Best-Fit Trend in Total Precipitation (mm/decade)
Annual 5.4
Winter (December to February) -0.6
Spring (March to May) -1.0
Summer (June to August) 4.4
Fall (September to November) 2.6
The following observations have been drawn from these figures and Table A-2: • Over the whole period of record, annual preciptitation totals have been steady within a significant band of inter-annual variability. • Over the past thirty years, annual precipitation totals have slightly been increasing at an average rate of approximately 5 mm/decade. • No trend was identified in the number of days with precipitaion. • Precipitation totals underlie strong seasonal impacts. Generally, in a given year, most precipitation falls during the summer. Summer and fall precipitation totals have shown increasing trends. Conversely, precipitation totals in spring and summer have shown decreasing trends.
A.3.3.2. Rainfall Totals Figure A-10 presents the historical annual and seasonal rainfall record. The following observations have been drawn from this figure:
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• Annual rainfall totals have been increasing by 5.9 mm per decade. • The count of days with rainfall have shown a slight decrease. • Strong seasonal controls on rainfall are evident, with the highest rate of rainfall increase for summer months, followed by fall and a general decrease in rainfall totals for the spring months.
A.3.3.3. Snowfall Totals Figure A-11 presents the historical annual and seasonal snowfall record. The following observations have been drawn from this figure: • Annual snowfall has been decreasing at a rate of -9.8 cm per decade. • Count of days with snowfall has been decreasing by -5.6 days per decade. • Trends of decreasing snowfall are consistent across all seasons, showing strongest in the spring months.
A.3.3.4. Snow Depth and Timing Figure A-12 presents the historical mean monthly snow depth record. Figure A-13 presents the first and last snow days of the year. The following observations have been drawn from these figures: • Monthly snow depths show no clear trend and were within the bounds of natural variability. • First and last snow days show no clear trend.
A.3.4. Extreme Climatic Events Extreme climatic events can last for a period of minutes or hours (e.g., hailstorms, high winds, blizzards, heavy snowfalls or rainfalls), days or weeks (e.g., warm or cold waves), or months, seasons and years (e.g., drought, warm or cold summer, winter, or years). Table A-3 summarizes extreme daily air temperatures, rainfall and snowfall in addition to extreme monthly rainfall and snowfall totals. Table A-3 shows that the highest daily rainfall on record occurred during the month of September. The greatest daily snowfall on record occurred during the month of May. Extreme minimum daily air temperatures have reached temperatures colder than -40ºC from December through March and have been subfreezing (colder than 0ºC) for all months. Extreme maximum daily temperatures have been above freezing (warmer than 0ºC) for all months of the year. Table A-4 summarizes the extreme climate events and the corresponding figures that have been prepared showing how these events have been distributed monthly and annually.
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Table A-3. Extreme Climatic Events, Cambridge Bay Airport, 1981 to 2010. Max Daily Rainfall Max Daily Min Daily Max Daily Month (mm) Snowfall (cm) Temperature (ºC) Temperature (ºC) Year Value Year Value Year Value Year Value
Jan 1993 0.2 1944 11.9 1935 -52.8 1987 -4.9 Feb 1929 0.0 1991 11.6 1955 -50.6 1941 -9.4 Mar 1929 0.0 1965 10.2 1936 -48.3 2006 -4.0 Apr 1975 3.8 1941 12.7 1972 -42.8 1940 6.1 May 1990 6.8 1972 15.7 1935 -35.0 1994 11.5 Jun 1997 19.4 1929 17.8 1974 -17.8 1996 23.3 Jul 1988 35.8 2009 2.6 1978 -1.7 1930 28.9 Aug 1949 30.7 1996 15.8 1952 -8.9 1991 26.1 Sep 1988 28.2 1997 10.2 1965 -17.2 2010 16.4 Oct 1963 10.4 1962 20.8 1978 -33.0 1988 6.9 Nov 1968 0.3 1940 15.2 2004 -43.9 1931 0.0 Dec 1930 0.0 1940 10.2 1934 -49.4 2010 -3.4
Table A-4. Extreme Climate Events at Cambridge Bay Airport. Extreme Figure Comment Climate Event Number
Snowfall A-14 No strong trend in the magnitude or annual occurrence of heavy snowfall days. (>= 10 cm) Heavy snowfall events have most frequently occurred during May.
Rainfall A-15 No strong trend in the magnitude or annual occurrence of heavy rainfall days. (>= 10 mm) Heavy rainfall events have most frequently occurred during July and August.
Rain on snow A-16 Rain on snow events occur from April to November, and occur most fequently during June.
Fog A-17 Fog has typically been observed during every month of the year but most frequently in February and March.
Freezing A-18 Freezing rain days occur during the spring and fall, most often during the months of precipitation May and October. There has been no observable trend in its annual occurrence.
Wind gusts A-19 Days with heavy gusts (>= 63 km/hr) have been recorded during all months, and most frequently during October. Wind gusts have occurred less frequently since 1980.
Extreme A-20 Extreme cold days occur most frequently from December to April. Extreme warm temperatures days occur most often from June to August. No discernible trend in extreme warm A-21 days was observed. Extreme cold days have occurred less frequently recently.
Wind Gusts A-22 Percent of wind gusts per year shows no clear trend. Predominant wind direction for all seasons is northwest. A-23
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A.3.4.1. Rainfall Intensities Rainfall Intensity-duration-frequency (IDF) curves are graphical representations of the probability that a given average rainfall intensity will occur at various event return periods. They are routinely used in water management and form the basis for runoff estimates and sizing of culverts, drain pipes and other water management infrastructure. Figure A-24 shows Environment Canada’s IDF curves for short duration rainfall at Cambridge Bay Airport (obtained from ftp://ftp.tor.ec.gc.ca/Pub/Engineering_Climate_Dataset/IDF/). These curves are based on data collected from the Cambridge Bay Airport climate station from 1969 to 2002. This provides a baseline for IDF values in the area. Climate change impacts on IDF curves will be discussed in Section A.4.2.
A.3.5. Summary In general, the following long-term trends have been observed at Cambridge Bay Airport: • A strong warming trend has been observed that is seasonally variable with fall and winter increases accounting for the majority of the annual air temperature increases. • The air freezing index has been decreasing and the air thawing index increasing with time, reflecting the long-term warming trend, with warming more pronounced during the winter. • There has been an overall slight decrease in the annual occurrence of freeze-thaw cycles. • Precipitation totals have been increasing with time. Rainfall totals have shown a slight increase with a shift towards later during summer, and snowfall totals have been decreasing. • No clear trends in extreme climatic events were observed.
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A.4. CLIMATE CHANGE PROJECTIONS
A.4.1. Long-Term Changes Typically two approaches are used in engineering design to project climate change: i) extrapolating recent historical climatic trends into the future, and ii) using complex global circulation models (GCMs) that simulate the complex interaction between greenhouse gas and aerosol emissions and their impact on the dynamic and physical processes, interactions, and feedbacks of the climate system. Extrapolation of historical climate data works best when the data record is continuous and over a long period and when projecting not too distant into the future (e.g., ten to twenty years as opposed to fifty years or more). Extrapolation of the most recent climate trend can be subjective, as different rates can be obtained depending on the timing and period of the data set being projected. Climatologists typically consider “normal” climate based on thirty-year averages. Representative Concentration Pathways (RCP) are greenhouse gas concentration trajectories which provide input to climate change models based on four possible scenarios developed by the Intergovernmental Panel on Climate Change (IPCC). The four scenarios are defined by their respective radiative forcing values for the year 2100: RCP2.6, RCP4.5, RCP6.0, and RCP8.5 (IPCC, 2013). For this analysis, RCP4.5 and RCP8.5 were selected as moderate and conservative estimates, respectively. Climate change projections from the Canadian Centre for Climate Modelling and Analysis (CCCma1) were considered for projected trends in mean annual air temperature and mean annual precipitation. The CanESM2 and CanRCM4 models were considered in the RCP4.5 and RCP8.5 scenarios for the previously listed climate parameters. The resulting climate change projections are summarized in Table A-5.
Table A-5. Climate change projections for 2045 relative to 1986-2005 values (Environment Canada). Model Change in Mean Annual Air Change in Mean Annual Temperature (ºC) Precipitation (%)
CanESM2 RCP4.5 3 - 4 10-20 CanESM2 RCP8.5 4 - 5 20-40 CanRCM4 RCP4.5 3 - 4 20-40 CanRCM4 RCP8.5 4 - 5 20-40
1 http://www.cccma.ec.gc.ca
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Projections provided by the Community Earth System Model (CESM2), which is a fully-coupled, global climate model that provides state-of-the-art simulations of the Earth's past, present, and future climate states, are provided by the National Science Foundation (NSF) and the U.S. Department of Energy (DOE). The model allows for seasonal projections using the RCP8.5 scenario.
Table A-6. Annual and seasonal climate change projections for 2036-2055 relative to 1986-2005 values (Climate Reanalyzer). Climate Parameter Annual Winter Spring Summer Fall Mean Temperature (ºC) 3.2-3.4 4.25-4.5 2.25-2.5 1.25-2.0 4.75-5.0 Precipitation (m) 0 0 0 0 0 Freezing Days (ºC) No data available Thawing Days (ºC) 200-225 0 0 150-200 50-100
A.4.2. Extreme Rainfall Events IDF curves are based on historical precipitation data at a particular climate station. As such, the information conveyed will be invalid for future conditions if precipitation characteristics follow a long-term trend, as is the case for this study area. For example, with a trend of increasing precipitation, a current 100-year rainfall event might become a 50-year rainfall event (i.e., twice as frequent). As this might lead to the under-design of drainage systems, development of IDF curves that take into account projected changes in rainfall intensity become an important objective. For the Cambridge Bay Airport, the online IDF CC Tool, a computerized tool for the development of IDF curves under climate change conditions, was used to generate IDF climate change predictions (http://www.idf-cc-uwo.ca/). The tool was developed at the University of Western Ontario in collaboration with the Canadian Water Network, and draws on Environment Canada’s IDF dataset. Climate change projections for Cambridge Bay from the following sources were considered: • MPI-ESM-LR, Max Planck Institute for Meteorology, Germany • CSIRO-Mk3-6-0, Australian Commonwealth Scientific and Industrial Research Organization, Australia • GFDL-ESM2G, National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamic Laboratory, USA • GFDL-CM3, National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamic Laboratory, USA • FGOALS_g2, Institute of Atmospheric Physics and Tsinghua University, China
2 http://www2.cesm.ucar.edu
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• CNRM-CM5, Centre National de Recherches Meteorologiques and Centre Europeen do Recherches et de Formation Avancee en Calcul Scientifique, France • HadGEM2-AO, National Institute of Meteorological Research, South Korea Of the above projections, the maximum values for RCP4.5 were represented by the MPI-ESM- LR projection and the minimum values were represented by the GFDL-ESM2G, CSIRO-Mk3- 6-0, and FGOALS_g2 projections. Of the RCP8.5 projections the maximum values were represented by the HadGEM2-AO and GFDL-CM3 projections. The minimum values for RCP8.5 were represented by the CNRM-CM5 projection. Figure A-25 and Figure A-26 present the current IDF values (determined from precipitation data for the period of 1969 to 2002) for each return period, as represented by solid coloured lines, in addition to projected ranges, as represented by coloured shaded areas, for the RCP4.5 and RCP8.5 scenarios, respectively. For both the RCP4.5 and RCP8.5 scenarios, the historical values fall at the lower bound of the range of predictions.
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A.5. SUMMARY Over the last half century, the Canadian Arctic has experienced a significant increase in temperature and a decrease in precipitation. Analysis of 58 years of climate data from Cambridge Bay Airport confirms the warming trend, but not the change in precipitation. Over the thirty-year period from 1986 to 2015, air temperatures in the Cambridge Bay area have been warming at an average rate of 0.6ºC/decade. Temperature anomalies appear to be associated with the Pacific Decadal Oscillations (PDO), although the correlation has waned over the past decade. Most of the warming has occurred during the fall and winter. Over the same thirty year period, precipitation totals in the area have been increasing at an average rate of about 5 mm/decade. Most of the increase in precipitation has occurred during the summer and shifted towards the fall, while precipitation totals have been decreasing during the spring. All global climate models project increases in temperature and precipitation over the Canadian Arctic, including the study area. Projected changes in air temperature and precipitation for the area are consistent with the average trend observed from the past thirty years.
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REFERENCES
Bonsal, B.R., Zhang, X., Vincent, L.A. and Hogg, W.D., 2001. Characteristics of daily and extreme temperature over Canada. Journal of Climate 14, 1959–1976. Brown, R.D. 2000. Northern Hemisphere snow cover variability and change, 1915–1997. Journal of Climate 13, 2339–2355. Cohen, J., Screen, J., Furtado, J., Barlow, M., Whittleston, D., Coumou, D., Francis, J., Dethloff, K., Entekhabi, D., Overland, J., and Jones, J. 2014. Recent Arctic amplification and extremem mid-latitudes weather. Nature Geoscience, 7, 627-637. Doré, G. and Zubeck, H. 2008. Cold regions pavement engineering. McGraw-Hill, NY. Duguay, C.R., Prowse, T.D., Bonsal, B.R., Brown, R.D., Lacroix, M.P. and Menard, P., 2006. Recent trends in Canadian lake ice covers. Hydrol. Process. 20, 781–801. Frauenfeld, O.W., Shang, T., and McCreight, J., 2007. Northern Hemisphere freezing/thawing index variations over the twentieth century. International Journal of Climatology 27: 1, 47-63. Hoeve, E., & Hayley, D. 2015. The Inuvik airport runway – an evaluation of 50 years of performance. In GEOQuébec 2015. 68th Canadian Geotechnical Conference, 7th Canadian Permafrost Conference. September 20–23, 2015, Québec-City, QC, Canada. Intergovernmental Panel on Climate Change (IPCC). 2013. The physical science basis, working group I. Cambridge University Press, New York. International Arctic Science Committee 2009. "Engineering design for a changing climate in the Arctic." In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [Published in the Encyclopedia of Earth October 11, 2009]. Instanes. A. and D. Mjureke, 2005. Svalbard Airport runway - performance during a climate warming scenario 2000–2050. Proceedings of the International Conference on Bearing Capacity of Roads and Airfields, Trondheim, Norway, 27–29 June 2005. Lacroix, M.P., Prowse, T.D., Bonsal, B.R., Duguay, C.R. and Ménard, P., 2005. River ice trends in Canada. Proceedings, Committee on River Ice Processes and the Environment 13th Workshop on the Hydraulics of Ice Covered Rivers. Hanover, NH, 15–16 September 2005. CGU—Committee on River Ice Processes and the Environment University of Edmonton, Edmonton, Alberta, 41–54. McBean, G., Alekseev, G., Chen, D., Førland, E., Fyfe, J., Groisman, P.Y., King, R.,Melling, H., Vose, R., and Whitfield, P.H., 2005. Arctic climate: past and present. In: Arctic Climate Impact Assessment. Cambridge University Press, Cambridge, UK, 22–60. Mekis, E. and Hogg, W.D., 1999. Rehabilitation and analysis of Canadian daily precipitation time series. Atmos.-Ocean 37, 53–85.
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Mills, B., Tighe, S.L., Andrey, J., Smith, J.T., and Huen, K., 2009. Climate change implications for flexible pavement design and performance in Southern Canada. Prowse, T.D., Furgal, C., Bonsal, B.R., and Edwards, T.W.D., 2009. Climatic conditions in northern Canada: past and future. Ambio, 38, 257-265 Zhang, X., Hogg, W.D. and Mekis, E., 2001. Spatial and temporal characteristics of heavy precipitation events over Canada. Journal of Climate 14, 1923–1936.
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FIGURES
Cambridge Bay Appendix A Climate Data Analysis.docx BGC ENGINEERING INC. Mean Annual Air Temperature 0
0.6ºC/decade -5
-10
-15
Mean Annual Air Temperature (ºC) Temperature Air Annual Mean -20
Maximum Annual Air Temperature 30
25
20
15 -0.7ºC/decade
Maximum Air Temperature (ºC) Temperature Air Maximum 10
Minimum Annual Air Temperature -30
0.8ºC/decade -35
-40
-45
Minimum Air Temperature (ºC) Temperature Air Minimum -50 1990 1996 2002 2008 2014 1986 1998 2004 1992 2010 2016 1988 1994 2000 2006 2012 1960 1966 1972 1978 1984 1962 1968 1974 1980 1964 1958 1970 1976 1982 Year
Annual 11-Year Running Average Best-Fit (1986-2015)
Note: Sufficient data to calculate annual values not available for 1992. Deviation from Mean (ºC) -2 -4 0 2 4 6
1958
1960
1962
1964
1966
1968
1970
Note: Sufficient data to calculate annualvaluesnot available 1972
1974
1976
1978
1980
1982
1984 Year 1986
1988
1990
1992
1994
1996 for 1992.
1998
2000
2002
2004
2006
2008 Source: http://research.jisao.washington.edu Oscillation PDO: Decadal Pacific 2010 /pdo/PDO.latest 2012
2014
2016 6 4 2 0 -2 -4
PDO Index Annual -8
-12
-16
-20 Winter (Dec, Jan, Feb) -24
-28
-32
-36
Spring (Mar, Apr, May) -14
-18
-22
-26
Summer (Jun, Jul, Aug) Mean Air Temperature (ºC) Temperature Air Mean 12
8
4
0
Fall (Sep, Oct, Nov) -4
-8
-12
-16 1996 2002 2008 2014 1990 1986 1998 2004 1992 2010 2016 2000 2006 2012 1988 1994 1978 1984 1960 1966 1972 1962 1980 1968 1974 1982 1958 1964 1970 1976 Year
Note: Sufficient data to calculate annual values not available for 1992. Mean Annual Air Temperature 0
-4 0.6ºC/decade -8
-12
-16
Mean Annual Air Temperature (ºC) Temperature Air Annual Mean -20
Freezing Index 7000
6500 -212ºC-days/decade 6000
5500
5000 Freezing Index (ºC-days) Index Freezing
4500
Thawing Index 2500
2000
42ºC-days/decade 1500
1000
500 Thawing Index (ºC-days) Index Thawing
0 1990 1996 2002 2008 2014 1986 1992 1998 2004 2016 2010 1994 2000 2006 2012 1988 1978 1984 1960 1966 1972 1962 1980 1968 1974 1982 1958 1964 1970 1976 Year
Annual 11-Year Running Average Best-Fit (1986-2015)
Note: Sufficient data to calculate annual values not available for 1992. Annual Freeze/Thaw Cycles 40 -0.8 cycles/decade
30
20
10
Spring Freeze/Thaw Cycles 30
1.1 cycles/decade
20
10
Number of Freeze/Thaw Cycles Freeze/Thaw of Number 0
Fall Freeze/Thaw Cycles 30 -0.1 cycles/decade
20
10
0 1990 1996 2002 2008 2014 1986 2004 1992 1998 2010 2016 1988 1994 2000 2006 2012 1966 1972 1978 1984 1960 1962 1974 1980 1968 1976 1982 1958 1964 1970 Year
Annual 11-Year Running Average Best-Fit (1986-2015)
Note: A freeze/thaw cycle is considered as having a maximum daily air tempertaure above 0oC and minimum daily air temperature below -1oC. Sufficient data to calculate annual values not available for 1992. Annual 240
200
160
120 5.4 mm/decade 80 Winter (Dec, Jan, Feb) 80
60 -0.6 mm/decade 40
20
0
Spring (Mar, Apr, May) 80
60 -1.0 mm/decade 40
20
0
Total Precipitation (mm)Precipitation Total Summer (Jun, Jul, Aug) 160 4.4 mm/decade 120
80
40
0
Fall (Sep, Oct, Nov) 160
120 2.6 mm/decade 80
40
0 1998 2004 1986 2010 2016 1992 2000 2006 2012 1988 1994 2002 2008 2014 1990 1996 1962 1968 1974 1980 1958 1964 1982 1970 1976 1960 1966 1972 1978 1984 Year
Total Best Fit (1986-2015) 11-Year Running Average
Note: Sufficient data to calculate annual values not available for 1992 and 1999. Annual Precipitation 240
200 5.4 mm/decade
160
120 Total Precipitation (mm) Precipitation Total
80 Annual Rainfall 160
5.9 mm/decade 120
80
Total Rainfall (mm) Rainfall Total 40
0 Annual Snowfall 160
120 -9.8 cm/decade
80
Total Snowfall (cm) Snowfall Total 40
0 1988 1994 2000 2006 2012 2002 1990 1996 2008 2014 1986 1992 1998 2004 2010 2016 1970 1976 1984 1960 1966 1972 1978 1962 1968 1974 1980 1958 1964 1982 Year Annual Best Fit (1986-2015) 11-Year Running Average
Note: Sufficient data to calculate annual precipitation values not available for 1992 and 1999. Sufficient data to calculate annual rain values not available for 1992, 1999, and 2015. Sufficient data to calculate annual snow values not available for 1992 and 2015. Count of Days with Precipitation 160
-0.3 days/decade 140
120
100
80 Total Precipitation (mm) Precipitation Total
60
Count of Days with Rainfall 100
-0.8 days/decade 80
60
40
Total Rainfall (mm) Rainfall Total 20
0
Count of Days with Snowfall 140
120 -5.6 days/decade
100
80
Total Snowfall (cm) Snowfall Total 60
40 1996 2008 2014 1990 2004 1986 2010 2016 1998 1992 2006 2000 2012 1988 1994 2002 1972 1978 1962 1980 1968 1974 1964 1958 1970 1976 1982 1960 1966 1984 Year
Total Best Fit (1986-2015) 11-Year Running Average
Note: Sufficient data to calculate annual precipitation values not available for 1992 and 1999. Sufficient data to calculate annual rain values not available for 1992, 1999, and 2015. Sufficient data to calculate annual snow values not available for 1992 and 2015. Annual 160 5.9 mm/decade 120
80
40
0
Winter (Dec, Jan, Feb) 20 16 12 8 4 0
Spring (Mar, Apr, May) 12
8 -0.5 mm/decade
4
Total Rain (mm)Rain Total 0
Summer (Jun, Jul, Aug) 160 3.8 mm/decade 120
80
40
0 Fall (Sep, Oct, Nov) 160 2.7 mm/decade 120
80
40
0 1996 2002 2008 2014 1990 1986 2004 1998 2010 2016 1992 2000 2006 2012 1988 1994 1960 1966 1984 1972 1978 1962 1974 1980 1968 1964 1958 1970 1976 1982 Year
Total Best Fit (1986-2015) 11-Year Running Average
Note: Sufficient data to calculate annual values not available for 1992, 1999, and 2015. Annual 140 -9.8 cm/decade 100
60
20 Winter (Dec, Jan, Feb) 60 -2.9 cm/decade 40
20
0 Spring (Mar, Apr, May) 60 -5.0 cm/decade 40
20
0 Total Snowfall (cm)Snowfall Total Summer (Jun, Jul, Aug) 60 -1.5 cm/decade 40
20
0 Fall (Sep, Oct, Nov) 60 -0.4 cm/decade 40
20
0 1992 1998 2016 2010 2006 1994 2000 1988 2012 1996 2002 1990 2008 2014 2004 1986 1968 1974 1980 1958 1964 1976 1982 1970 1960 1966 1984 1972 1978 1962 Year
Total Best Fit (1986-2015) 11-Year Running Average
Note: Sufficient data to calculate annual values not available for 1992 and 2015. October to January 60
50
40
30
20 Mean Snow Depth (cm)Snow Mean
10
0 January to May 60
50
40
30
20 Mean Snow Depth (cm)
10
0 1992 1998 2004 2016 2010 1994 2000 2006 1988 2012 1990 1996 2002 2008 2014 1962 1968 1974 1980 1986 1958 1964 1982 1970 1976 1960 1966 1972 1978 1984 October December February April November January March May
Note: 11-year running average and 1986-2015 best fit trends also shown. Sufficient data to calculate annual values not available for 1992 and 2015. Last Snow Day First Snow Day 30-May 20-Aug 29-Sep 19-Jun 29-Jun 19-Oct 31-Jul 9-Sep 8-Nov 9-Jun 9-Jul
1958 1958 1960 1960
Note: Sufficientdata to calculateannualvaluesnot available 1962 1962 1964 1964 1966 1966 1968 1968 1970 1970 1972 1972 1974 1974 1976 1976 First SnowDay 1978 Last SnowDay 1978 1980 1980 1982 1982 1984 1984 Year Year 1986 1986 1988 1988 1990 1990 1992 1992 1994 1994 1996 1996 1998 1998 for 2015. 2000 2000 2002 2002 2004 2004 2006 2006 2008 2008 2010 2010 2012 2012 2014 2014 2016 2016 Average Number of Days 0.02 0.04 0.06 Snowfall (cm) Number of Days 10 15 20 25 1 2 0 0 5 0
1958 1958 Note: Sufficientdata to calculateannualvalues not available 1960 1960 a e a p a u u u e c o Dec Nov Oct Sep Aug Jul Jun May Apr Mar Feb Jan 1962 1962 1964 1964 Average Number Days of per Month with Snowfall >= 10 cm 1966 1966
1968 1968 Amount of Snowfall onDays with Snowfall>= 10 cm 1970 1970
1972 Number of Days with Snowfall >= 10 cm 1972 1974 1974 1976 1976 1978 1978 1980 1980 1982 1982 1984 1984 1986 1986 1988 1988 1990 1990 1992 1992 1994 1994
for 1992 and 2015. 1996 1996 1998 1998 2000 2000 2002 2002 2004 2004 2006 2006 2008 2008 2010 2010 2012 2012 2014 2014 2016 2016 Average Number of Days Rainfall (mm) 100 0.1 0.2 0.3 0.4
Number of Days 20 40 60 80 0 1 2 3 4 5 0 0 Note: Sufficient data tocalculate annual valuesnotavailable 1958 1958 1960 1960 a e a p a u u u e c o Dec Nov Oct Sep Aug Jul Jun May Apr Mar Feb Jan 1962 1962 1964 1964 Average Number of Days per Month with Rainfall >= 10 mm 1966 1966
1968 1968 Amount of Rainfall onDays with Rainfall>= 10 mm 1970 1970
1972 Number Days of with Rainfall >= 10 mm 1972 1974 1974 1976 1976 1978 1978 1980 1980 1982 1982 1984 1984 1986 1986 1988 1988 1990 1990 1992 1992 for 1992,1999, and 2015. 1994 1994 1996 1996 1998 1998 2000 2000 2002 2002 2004 2004 2006 2006 2008 2008 2010 2010 2012 2012 2014 2014 2016 2016 Rain on Snow Totals 120 Number of Rain on Snow Days Days w/Rainfall 0.3-1 mm 100 Days w/Rainfall 1-5 mm Days w/Rainfall 5-10 mm Days w/Rainfall >10 mm 80
60 Number of Days of Number 40
20
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total Rainfall on Snow 300
250
200
150 Rainfall (mm) Rainfall
100
50
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Number of Hours Per Month With Visibility <1 km 50
40
30
20 Number of Hours of Number 10
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of Hours Per Month With Visibility 1 to 9 km 200
160
120
80 Number of Hours of Number 40
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of Hours Per Month With Visibility >9 km 800
600
400
Number of Hours of Number 200
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1971-2000 1981-2010 Average Number of Freezing Rain Days per Month 0.8
0.6
0.4 Average Number of Days of Number Average 0.2
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Total Number of Freezing Rain Days 8
6
4 Number of Days of Number
2
0 1988 1994 2012 1984 2002 1990 1996 2008 2014 1986 1992 1998 2004 2010 2016 2006 2000 1960 1966 1972 1978 1962 1974 1980 1968 1958 1964 1970 1976 1982
Note: Sufficient data to calculate annual values not available for 1992, 1999, and 2015. Average Number of Days per Month with Mean Wind >= 63 km/h 4
3
2
1 Average Number of Days of Number Average
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Wind Gusts >= 63 km/h 160
120
80
40 Wind Speed (km/h) Speed Wind
0
Number of Wind Gusts 100
80 >= 63 km/h >= 90 km/h 60
40
Number of Events of Number 20
0 1994 2004 1992 2014 2002 1990 2012 2000 2010 1988 1998 2008 1986 1996 2006 1984 2016 1962 1972 1960 1982 1970 1980 1968 1978 1966 1976 1964 1974
Note: No data available for 1958-1959, 1995-2001. Number of Days 120 40 80 0
Occurrence
0.1 0.2 0.3 0.4 Occurrence 0.2 0.4 0.6 0.8
1960 0 1 0 a e a p a u u u e c o Dec Nov Oct Sep Aug Jul Jun May Apr Mar Feb Jan
1964 Dec Nov Oct Sep Aug Jul Jun May Apr Mar Feb Jan 1968 1972
Note: Sufficientdata to calculateannualvaluesnot available 1976 1980 1984 1988 1992 1996
2000 Extreme Heat Occurrence Extreme Cold Occurrence 2004 2008 2012
Number of Days 10 20 30 40 0
1960 1964 1968 1972 for 1992. 1976 1980 <= -45 <= -40 <= -35 1984 1988 >= 20 >= 15 o o o 1992 C C C o o C C 1996 2000 2004 2008 2012 Temperature (ºC) Temperature (ºC) Extreme Cold Probability Curves Extreme Hot Probability Curves 0 0.08 0.16 0.24 0.32 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 0.32 Wind Gusts per Year (%) 100% 20% 40% 60% 80% 0%
1958 1960
270 1962 1964 1966 1968 315 225 Frequency of Wind Gusts (>31 km/h) per Year Note: Data not available for 1958-1959, 1995-2001. 1970 1972 1974 1976 1978 1980 Wind Rose 1982 180 %4 %12% 8% 4% 0% 1984 0 Year 1986 1988 1990 1992 1994 1996 1998 135 45 2000 2002 2004 90 Wind Gusts(km/h) 2006
>60 >50 - 60 >40 - 50 >31 - 40 2008 2010 2012 2014 2016 Wind Gusts (km/h) Wind Gusts (km/h) Winter Wind Rose Spring Wind Rose 0 >31 - 40 0 >31 - 40 >40 - 50 >40 - 50 >50 - 60 315 45 >50 - 60 315 45 >60 >60
270 90 270 90
0% 8% 16% 0% 4% 8% 12%
225 135 225 135
180 180
Wind Gusts (km/h) Summer Wind Rose Wind Gusts (km/h) >31 - 40 0 >31 - 40 0 >40 - 50 >40 - 50 >50 - 60 315 45 >50 - 60 315 45 >60 >60
270 90 270 90
0% 4% 8% 0% 4% 8% 12%
225 135 225 135
180 180 Transport Canada, PIEVC Climate Change Vulnerability Assessment May 13, 2016 Cambridge Bay Airport Project No.: 0727-004
Figure A-24 Cambridge Bay Rainfall IDF BGC ENGINEERING INC. 100
10 Intensity(mm/hr)
1 Return Period 2 Years 5 Years 10 Years 25 Years 50 Years 100 Years
0.1 1 10 100 1000 10000 Duration (minutes)
Shaded areas represent climate change predictions from 2015-2045 100
10 Intensity (mm/hr) Intensity
1 Return Period 2 Years 5 Years 10 Years 25 Years 50 Years 100 Years
0.1 1 10 100 1000 10000 Duration (minutes)
Shaded areas represent climate change predictions from 2015-2045 Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
APPENDIX B CLIMATE CHANGE VULNERABILITY ASSESSMENT MATRIX - DRAFT
Cambridge Bay Climate Vulnerability Report.docx BGC ENGINEERING INC. PIEVC Engineering Protocol for Climate Change Infrastructure Vulnerability Assessment Risk Matrix Cambridge Bay.xlsx
132 4 5 6 7 8 9 Air Temperatures Infrastructure Response Considerations Maximum Air Minimum Air Air Freezing Index Air Thawing Index Freeze - Thaw Cycles Heat Waves Cold Waves Frost Rainfall Frequency Temperature Temperature
Infrastructure Components
Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Structural Design Functionality Serviceability & Groundwater Water Surface Watershed, Operations, Maintenance & Materials Performance Response Emergency Considerations Economical Policy Considerations Social Effects Environmental Effects Mark Relevant Responses with ✓ Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Phyiscal Infrastructure
1 Runway √√√ √√√√√√ Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0
2 Taxiways √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
3 Aprons √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
4 Drainage System √√√√√ √ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
5 Access and Service Roads √√√ √√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
6 Heteo. in Natural Foundation / Permafrost √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
Supporting Infrastructure
7 O&M Personnel √√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
8 Snow clearing √√√√√√√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
9 Resurfacing √√ √√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00 √√√√√ Y Y Y Y Y Y Y Y Y 10 Winter flight operation 000000000000000000 √√√√√ Y Y Y Y Y Y Y Y Y 11 Summer flight operation 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 12 Summer maintenance 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 13 Winter maintenance 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 14 Lightining systems 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 15 Surface marking 000000000000000000 √√√ √√ √ √ Y Y Y Y Y Y Y Y Y 16 Environmental monitoring 000000000000000000 √ √√√√ Y Y Y Y Y Y Y Y Y 17 Navaids 000000000000000000 √√ √ √ Y Y Y Y Y Y Y Y Y 18 Vegetation 000000000000000000 √√√ √ √ Y Y Y Y Y Y Y Y Y 19 Security structures 000000000000000000 √√√√√ √ √ Y Y Y Y Y Y Y Y Y 20 Data Availability 000000000000000000
Others √√ √ Y Y Y Y Y Y Y Y Y 21 Emergency procedures and medevac 000000000000000000 √√ Y Y Y Y Y Y Y Y Y 22 Wildlife 000000000000000000 √√√√Y Y Y Y Y Y Y Y Y 22 Future developments / Masterplan 000000000000000000 √√√√√√Y Y Y Y Y Y Y Y Y 23 Municipal Services 000000000000000000
Page 1 of 4 PIEVC Engineering Protocol for Climate Change Infrastructure Vulnerability Assessment Risk Matrix Cambridge Bay.xlsx
10 11 12 13 14 15 16 17 18 Precipitation Infrastructure Response Considerations Rainfall Intensity Rainfall Duration Rainfall in the Fall Freezing Rain Rain on Snow Total Snowfall Snowfall Duration Snowfall Frequency First Snow Day (Rain Storms)
Infrastructure Components
Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Structural Design Functionality Serviceability & Groundwater Water Surface Watershed, Operations, Maintenance & Materials Performance Response Emergency Considerations Economical Policy Considerations Social Effects Environmental Effects Mark Relevant Responses with ✓ Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Phyiscal Infrastructure
1 Runway √√√ √√√√√√ Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0
2 Taxiways √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
3 Aprons √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
4 Drainage System √√√√√ √ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
5 Access and Service Roads √√√ √√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
6 Heteo. in Natural Foundation / Permafrost √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
Supporting Infrastructure
7 O&M Personnel √√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
8 Snow clearing √√√√√√√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
9 Resurfacing √√ √√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00 √√√√√ Y Y Y Y Y Y Y Y Y 10 Winter flight operation 000000000000000000 √√√√√ Y Y Y Y Y Y Y Y Y 11 Summer flight operation 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 12 Summer maintenance 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 13 Winter maintenance 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 14 Lightining systems 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 15 Surface marking 000000000000000000 √√√ √√ √ √ Y Y Y Y Y Y Y Y Y 16 Environmental monitoring 000000000000000000 √ √√√√ Y Y Y Y Y Y Y Y Y 17 Navaids 000000000000000000 √√ √ √ Y Y Y Y Y Y Y Y Y 18 Vegetation 000000000000000000 √√√ √ √ Y Y Y Y Y Y Y Y Y 19 Security structures 000000000000000000 √√√√√ √ √ Y Y Y Y Y Y Y Y Y 20 Data Availability 000000000000000000
Others √√ √ Y Y Y Y Y Y Y Y Y 21 Emergency procedures and medevac 000000000000000000 √√ Y Y Y Y Y Y Y Y Y 22 Wildlife 000000000000000000 √√√√Y Y Y Y Y Y Y Y Y 22 Future developments / Masterplan 000000000000000000 √√√√√√Y Y Y Y Y Y Y Y Y 23 Municipal Services 000000000000000000
Page 2 of 4 PIEVC Engineering Protocol for Climate Change Infrastructure Vulnerability Assessment Risk Matrix Cambridge Bay.xlsx
19 20 21 22 23 24 25 26 27
Infrastructure Response Considerations Blizzards / Ground Freezing Ground Thawing Last Snow Day Ice Storms Hail Wind Gusts Wind Direction Wind in Winter White-Outs Index Index
Infrastructure Components
Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Structural Design Functionality Serviceability & Groundwater Water Surface Watershed, Operations, Maintenance & Materials Performance Response Emergency Considerations Economical Policy Considerations Social Effects Environmental Effects Mark Relevant Responses with ✓ Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Phyiscal Infrastructure
1 Runway √√√ √√√√√√ Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0 Y 0
2 Taxiways √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
3 Aprons √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
4 Drainage System √√√√√ √ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
5 Access and Service Roads √√√ √√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
6 Heteo. in Natural Foundation / Permafrost √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
Supporting Infrastructure
7 O&M Personnel √√ √√√√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
8 Snow clearing √√√√√√√ √ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00
9 Resurfacing √√ √√√√ Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00Y 00 √√√√√ Y Y Y Y Y Y Y Y Y 10 Winter flight operation 000000000000000000 √√√√√ Y Y Y Y Y Y Y Y Y 11 Summer flight operation 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 12 Summer maintenance 000000000000000000 √√ √√√√ √ Y Y Y Y Y Y Y Y Y 13 Winter maintenance 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 14 Lightining systems 000000000000000000 √√√√ Y Y Y Y Y Y Y Y Y 15 Surface marking 000000000000000000 √√√ √√ √ √ Y Y Y Y Y Y Y Y Y 16 Environmental monitoring 000000000000000000 √ √√√√ Y Y Y Y Y Y Y Y Y 17 Navaids 000000000000000000 √√ √ √ Y Y Y Y Y Y Y Y Y 18 Vegetation 000000000000000000 √√√ √ √ Y Y Y Y Y Y Y Y Y 19 Security structures 000000000000000000 √√√√√ √ √ Y Y Y Y Y Y Y Y Y 20 Data Availability 000000000000000000
Others √√ √ Y Y Y Y Y Y Y Y Y 21 Emergency procedures and medevac 000000000000000000 √√ Y Y Y Y Y Y Y Y Y 22 Wildlife 000000000000000000 √√√√Y Y Y Y Y Y Y Y Y 22 Future developments / Masterplan 000000000000000000 √√√√√√Y Y Y Y Y Y Y Y Y 23 Municipal Services 000000000000000000
Page 3 of 4 PIEVC Engineering Protocol for Climate Change Infrastructure Vulnerability Assessment Risk Matrix Cambridge Bay.xlsx
28 29 30 31 32
Infrastructure Response Considerations Cloud Cover / Solar Lightning / Electrical Cloud Ceiling Height Fog / Visibility Climate Variability Radiation Storms
Infrastructure Components
Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Enter Infrastructure Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Threshold Value Here Structural Design Functionality Serviceability & Groundwater Water Surface Watershed, Operations, Maintenance & Materials Performance Response Emergency Considerations Economical Policy Considerations Social Effects Environmental Effects Mark Relevant Responses with ✓ Y/N P S R Y/N P S R Y/N P S R Y/N P S R Y/N P S R Phyiscal Infrastructure
1 Runway √√√ √√√√√√ Y 0 Y 0 Y 0 Y 0 Y 0
2 Taxiways √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00
3 Aprons √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00
4 Drainage System √√√√√ √ √ Y 00Y 00Y 00Y 00Y 00
5 Access and Service Roads √√√ √√ √ Y 00Y 00Y 00Y 00Y 00
6 Heteo. in Natural Foundation / Permafrost √√√ √√√√√√ Y 00Y 00Y 00Y 00Y 00
Supporting Infrastructure
7 O&M Personnel √√ √√√√√√ Y 00Y 00Y 00Y 00Y 00
8 Snow clearing √√√√√√√ √ Y 00Y 00Y 00Y 00Y 00
9 Resurfacing √√ √√√√ Y 00Y 00Y 00Y 00Y 00 √√√√√ Y Y Y Y Y 10 Winter flight operation 0000000000 √√√√√ Y Y Y Y Y 11 Summer flight operation 0000000000 √√ √√√√ √ Y Y Y Y Y 12 Summer maintenance 0000000000 √√ √√√√ √ Y Y Y Y Y 13 Winter maintenance 0000000000 √√√√ Y Y Y Y Y 14 Lightining systems 0000000000 √√√√ Y Y Y Y Y 15 Surface marking 0000000000 √√√ √√ √ √ Y Y Y Y Y 16 Environmental monitoring 0000000000 √ √√√√ Y Y Y Y Y 17 Navaids 0000000000 √√ √ √ Y Y Y Y Y 18 Vegetation 0000000000 √√√ √ √ Y Y Y Y Y 19 Security structures 0000000000 √√√√√ √ √ Y Y Y Y Y 20 Data Availability 0000000000
Others √√ √ Y Y Y Y Y 21 Emergency procedures and medevac 0000000000 √√ Y Y Y Y Y 22 Wildlife 0000000000 √√√√Y Y Y Y Y 22 Future developments / Masterplan 0000000000 √√√√√√Y Y Y Y Y 23 Municipal Services 0000000000
Page 4 of 4 Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
APPENDIX C WORKSHOP PRESENTATION
Cambridge Bay Climate Vulnerability Report.docx BGC ENGINEERING INC. PIEVC Vulnerability Assessment – Cambridge Bay
Workshop Overview
Sunday, July 26 Site Visit 4:00 pm – 6:00 pm Monday, July 27 Introduction 8:00 am – 10:00 am Break-out Session I 10:30 am – 12:00 pm Lunch 12:00 pm – 1:00 pm Break-out Session II 1:00 pm – 2:30 pm PIEVC Vulnerability Assessment Break-out Session III 3:00 pm – 5:00 pm Tuesday, July 28 Cambridge Bay Airport Continuation of Discussions 8:00 am – 9:30 am Wrap-up 10:00 am – 12:00pm
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Presentation Overview
•Welcome • Introduction of Participants and Project • Climate Change Vulnerability Assessment Protocol Introduction • Cambridge Bay Airport Background • Climate Change and Cambridge Bay Airport • Overview of Workshop • Site Visit
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Cambridge Bay Airport Cambridge Bay Airport
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July 2015 ‐ BGC Engineering Inc. 1 PIEVC Vulnerability Assessment – Cambridge Bay
Cambridge Bay Airport Cambridge Bay Airport
• Airport originally constructed in 1956-1958 • Located 2.7 km southwest of the community of Cambridge Bay • Aircraft movements: 6,215 • Gravel runway, • 150 ft (45 m) wide by 5000 ft (1524 m) long • Located in continuous permafrost
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Engineers Canada Presentation PIEVC Protocol for Climate Change Vulnerability Assessment
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5 Step Protocol Step 3: Risk Assessment
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July 2015 ‐ BGC Engineering Inc. 2 PIEVC Vulnerability Assessment – Cambridge Bay
Risk Probability, P
The possibility of injury, loss, or negative environmental impact created by a hazard. The significance of risk is a function of the probability of an unwanted incident and the severity of its consequence. In mathematical terms: Where: R = Risk P = Probability of a negative event S = Severity of the event, given that it has happened
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Probability Scoring Severity, S
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Risk Tolerance Thresholds Risk Matrix
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July 2015 ‐ BGC Engineering Inc. 3 PIEVC Vulnerability Assessment – Cambridge Bay
Risk Matrix Climate Events and Change Factors I
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Climate Events and Change Factors II Performance Response Consideration I
1. Structural Design 2. Functionality o Safety o Effective Capacity of the . Load carrying capacity . Overturning infrastructure . Sliding . Short term . Fracture . Medium term . Fatigue . Long term . Serviceability o Equipment – Component o Deflection Selection . Permanent deformation . Cracking and deterioration . Design, process and capacity . Vibration considerations o Foundation Design . Permafrost
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Performance Response Consideration II Performance Response Consideration III
3. Serviceability 4. Watershed, Surface Water, and 5. Operations, Maintenance, and 6. Emergency Response Groundwater Materials Performance o Procedures and systems to o Ability to conduct routine o o Erosion scour of associated or supporting Occupational safety address and/or planned earthworks o Access to worksite . Severe storm events maintenance and o Slope stability of embankments o Structural integrity . Flooding refurbishment activities o Sediment transport and sedimentation o Equipment performance . Ice dams . Maintenance and replacement o Channel realignment/meandering . Ice accretion . Short term cycles o Water quality . Water damage . Medium term . Electricity demand o Water quantity . Fuel use . Long term 7. Insurance Considerations o Water resource demands o Functionality & Effective o Insurance rates o Equipment – Component . Public, hydro, industrial, agricultural use of Capacity water resources o The ability to acquire Replacement frequencies o Materials Performance . Groundwater recharge characteristics insurance . Design, process and . Changes from design expectation o Run off o Insurance policy limitations capacity considerations o Pavement Performance o Recharge . Hail, softening, cracking from and exclusions o Thermal characteristics of the water resource freeze thaw and other causes
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July 2015 ‐ BGC Engineering Inc. 4 PIEVC Vulnerability Assessment – Cambridge Bay
Performance Response Consideration IV Probability Scoring
8. Policy Considerations 10. Social Effects 1 Infrastructure Response o Codes Climate Parameter 1 o Accessibility to critical facilities such Considerations o Guidelines as hospitals, fire and police services o Standards o o Internal operations and Transportation of goods to a maintenance policies and community procedures o Energy supply to a community Enter rationale for o Public sector policy Infrastructure Components o Dislocation of affected populations Enter Infrastructure Infrastructure Threshold Threshold Value here. Identify reference to o Land use planning Here code or standard if o Provision of basic services such as relevant. 9. Environmental Effects potable water distribution and o Release of toxic or controlled wastewater collection substances o Closure of public services o Degradation of air quality
o Community business viability StructuralDesign Functionality Serviceability Groundwater & Water Surface Watershed, Performance Materials & Maintenance Operations, EmergencyResponse Considerations Insurance Considerations Policy Effects Social Effects Environmental o Damage to sensitive ecosystems Rationale For Severity Mark Relevant Responses with ✓ Y/N P S R o Physical harm to birds and o Destruction or damage to heritage Score
1 Component 1
animals buildings, monuments, 2 Component 2 o Contamination of potable water 3 Component 3 archaeological resources, 456 supplies historically important resources, etc. o Public perception and interaction
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Cambridge Bay Airport
Cambridge Bay Airport
Background
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Cambridge Bay Airport 2010 Master Plan
Short Term Recommendations (2-5 years) • Provision of runway graded areas and shoulders • Extension of Apron I • New Taxiway C connecting expanded apron to Runway 31 • Extension of Runway 13T-31T to 6000 ft (1829 m) • Expansion of Air Terminal Building to 841 m2
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July 2015 ‐ BGC Engineering Inc. 5 PIEVC Vulnerability Assessment – Cambridge Bay
2010 Master Plan 2010 Master Plan
Medium Term Recommendations (5-10 years) Long Term Recommendations (10-20 years) • New Airside commercial lots and Taxiway D for access • Extension of the Airside Commercial lots • Replacement of edge lighting with solid state systems • Extension of Taxiway D to service expanded • Expansion of Air Terminal Building to 1160 m2 Airside Commercial lots • Replace Field Electrical Centre with larger system • Realign airport access road to service new commercial lots • Installation of Precision Approach Capability associated High Intensity Lighting • Paving of Runways, Taxiways, and Apron
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2010 Master Plan 2010 Master Plan
Capital Cost Estimates for Short Term: Airside: $30.5 million Air Terminal Building: $2.6 million Groundside: $1.3 million
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Climate Normals
Climate Change
Cambridge Bay, Nunavut
Environment Canada
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July 2015 ‐ BGC Engineering Inc. 6 PIEVC Vulnerability Assessment – Cambridge Bay
Climate Baseline Historical Climate Trends – Air Climate Normals (1981-2010) Temperature
Air Temperature Wind Speed Precipitation Daily Solar Month (oC) (km/hr) (mm) Radiation (MJ/m2) January -32.0 19.9 5.8 1 February -32.5 19.8 4.9 5 March -29.3 19.3 7.1 14 April -20.8 19.2 5.7 24 May -9.3 19.0 7.0 31 June 2.7 18.2 13.6 32 July 8.9 18.2 24.1 30 August 6.8 19.6 25.7 23 September 0.3 20.7 19.1 14 October -10.4 21.9 14.7 7 November -22.3 19.6 8.0 2
December -28.3 19.6 6.1 0 Environment Canada Annual -13.9 19.6 141.7 - bgcengineering.com bgcengineering.com
Historical Climate Trends – Air Temperature Extrema Temperature
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Historical Climate Trends – Air Historical Climate Trends - Temperature Precipitation
• Annual air temperatures have been steadily increasing over the past 30 years • The number of freeze/thaw cycles in fall months have been steadily declining over the past 30 years
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July 2015 ‐ BGC Engineering Inc. 7 PIEVC Vulnerability Assessment – Cambridge Bay
Freezing Rain Historical Climate Trends - Precipitation • Annual mean precipitation has shown a steady increase over the past 30 years • Winter and Spring months show decreased precipitation, while Summer and Fall months show increased precipitation • No trend in freezing rain days
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Historical Climate Trends – Snow Historical Climate Trends – Snow Cover Cover
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Historical Climate Trends – Snow Consequences for Runway Cover Performance • First snow days have occurred later in the season • Warmer air temperatures mean warmer permafrost in recent years temperatures; warmer summer air temperatures results in increased depths of seasonal thaw. • Last snow days show no trend • Increased snowfall results in increased snow depth • Snow depths have decreased slightly in recent which would insulates the embankment slopes from years the cold winter air temperatures thereby having a similar thermal impact as warmer air temperatures. • Increased precipitation could result in more surface and groundwater flow which could contribute to convective warming if it flows through the embankment.
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July 2015 ‐ BGC Engineering Inc. 8 PIEVC Vulnerability Assessment – Cambridge Bay
Consequences for Runway Historical Climate Trends – Wind Performance
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Wind Direction Historical Climate Trends – Visibility
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Climate Change Projections Climate Change – Air Temp.
SAT (°C)
Surface Air Temperature Trends 2010 - 2060
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Zhang et al., 2014 Deser et al., 2014
July 2015 ‐ BGC Engineering Inc. 9 PIEVC Vulnerability Assessment – Cambridge Bay
Climate Change – Air Temp. Climate Change – Precipitation
mm/day Stdv (°C) (51 years)
Surface Air Temperature Trends 2010 - 2060
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Deser et al., 2014 Deser et al., 2014
Climate Change – Precipitation Chance of Trend
Stdv. mm/day (51 years)
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Deser et al., 2014 Deser et al., 2014
Chance of Trend Climate Change – Wind Gusts
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Deser et al., 2014 Check et al., 2014
July 2015 ‐ BGC Engineering Inc. 10 PIEVC Vulnerability Assessment – Cambridge Bay
Climate Change Projections Active Layer
Global warming By 2045 (~30 years): Time Typical soil type • Increase in mean annual air temperature: 3 – 4°C
o More winter than summer warming Embankment Fill Active layer thickness may increase 3m
• Increase in precipitation: 10 – 20% Peat (soft) 5m Engineering problem?
• Increase in wind gust frequency (2081-2100) Till, clayey silt and gravel o Spring: -10 – 10%; Summer, Autumn, Winter: 10 – 30%; Frozen
Depth bgcengineering.com bgcengineering.com
Koichi Hayashi
Permafrost and Climate Change Permafrost and Climate Change
IPCC, 2013
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Sea Level Change Sea Level Change
• Relative sea level rise comprised of global sea level rise and local postglacial uplift • Present rate of postglacial uplift is 3.7±2 mm/year • Projected global sea level change for the next 30 years is up to +30 cm • Longer open water season
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July 2015 ‐ BGC Engineering Inc. 11 PIEVC Vulnerability Assessment – Cambridge Bay
Sea Level Change Sea Level Change
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Sea Level Change
Workshop
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Team Member Goal
• Input for the risk matrix, concentrating on severity values • Finding good justifications and reasons for the assigned values • Work in groups, i.e. break-out sessions • Change groups • Develop dynamics
Each individual’s opinion is valued
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July 2015 ‐ BGC Engineering Inc. 12 PIEVC Vulnerability Assessment – Cambridge Bay
Break-out Sessions Climate Events
• Average Daily Air Temperature • Hail • Three Workshop / Break-out Sessions allocated • Freezing Index • Snow Accumulation • After Site Visit • Thawing Index • Snow Storms- Duration • Freeze / Thaw Cycles • Snow Storms- Frequency • Minimum Air Temperatures • Snow Timing Session 1: Session 2: Session 3: • Maximum Air Temperatures • Blowing Snow • Diurnal Temperature Variability • Rain on Snow Discussion on Severity Discussion of Severity and • Heat Wave • Gusts / Extreme Wind / Storm Events Infrastructure Combinations Probability Discussion • ColdWave • IceStorms Components & Climate of Combinations • Rainfall – Frequency • Change in Groundwater Table Events • Rainfall – Duration • Flooding • Rainfall Intensity / Storms • Forest Fire • Fall Rainfall • Fog / Visibility • Sea Level bgcengineering.com bgcengineering.com
Infrastructure Components
Physical Infrastructure: Supporting Systems/Infrastructure • Runway System • Marking
o Surface • Lightning o Fill
o Foundation • Vegetation • Taxiway System Maintenance & Operation Site Visit o Surface • Winter Flight Operation o Fill
o Foundation • Summer Flight Operation • Apron • Snow Clearing • Roads • De-icing • Drainage System • Crack Filling – Cold Patch o Culverts • Summer Maintenance o Ditches and Channels
o Ponds • Weather Station o Berms • Monitoring • Security Fence Other bgcengineering.com • Emergency Procedures bgcengineering.com • Medevac
Goal Thank You! • Visiting Infrastructure Components • Appreciation for Environmental Conditions • Understanding Problems • Discover new Components and Potential Interactions
• Interactive Trip -> PLEASE Interrupt Ask Questions Discuss Make Notes
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July 2015 ‐ BGC Engineering Inc. 13 Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
APPENDIX D NON-TECHNICAL EXECUTIVE SUMMARY
Cambridge Bay Climate Vulnerability Report.docx BGC ENGINEERING INC. Transport Canada, PIEVC Climate Change Vulnerability Assessment May 17, 2016 Cambridge Bay Airport – FINAL Project No.: 0727-004
Executive Summary
The Public Infrastructure Engineering Vulnerability Committee (PIEVC) has developed a standardized protocol to assess the vulnerability of Canada’s public infrastructure to climate change. Case studies have been carried out to date across Canada, testing and calibrating this protocol on various infrastructures. BGC Engineering Inc. was commissioned by Transport Canada in partnership with the Government of Nunavut Territories and with Engineers Canada to apply the vulnerability assessment protocol to the Cambridge Bay Airport. The airport is located on Victoria Island, Nunavut, approximately 2.6 km west of the hamlet of Cambridge Bay, and is owned by the Government of Nunavut. It was constructed in the 1950s and is the only airport in Canada where jet aircraft land on a gravel runway. Runway 13-31T is 5000 ft long, currently extended to 6000 ft. In 2015, about 4,600 aircraft movements were recorded, of which 11% were jet aircraft movements. Following the PIEVC protocol, more than 700 infrastructure element – climate event combinations were formed to be assed in future stages. To date, no risk workshop was conducted and recommendations provided are based on documentations available and BGC’s experience only. No immediate engineering action is expected to be required to address impacts from climate change as per our current project understanding. The components do have sufficient resilience considering available historic data and future projections. There are, however, significant uncertainties and data gaps that should be reduced by increasing environmental monitoring efforts, systematic record keeping of maintenance efforts and reviewing operation practices. The following actions are recommended based on the initial assessment: • Evaluate the capacity of drainage systems to assess the resiliency of culverts and ditches against higher flows, and measure runoff and changes in surface water bodies; • Systematically collect information on the visibility in the form of detailed logbook /database on the weather conditions at the time and the characteristics of the limited visibility event; • Collect data on frost formation, such as climate parameters, timing, location and extent; • Review frost management procedures; • Update or develop an asset management system, including an evaluation of current infrastructure service lives; • Monitor local snow accumulation, including spatial (re-)distribution and note limitations to operations; • Automated measurement of ground temperatures at various locations across the airport property; • Document in a logbook / database climate-related flight delays/cancellations, as well as maintenance and repair activities, including date, location, type and extent; and • Carry out an initial climate change vulnerability assessment with several stakeholders that include the airport operators, the owners and users of the airport, and re-evaluate it every five years, as new baseline data, infrastructure performance information, and improved climate models become available. The changing climate will likely result in increased maintenance and repair efforts for which resources must be provided. Collection of additional baseline data will help making informed decisions in the near future on where resources are best allocated.
Cambridge Bay Climate Vulnerability Report.docx BGC ENGINEERING INC.