(1915-2014) to Permafrost Science in Canada

Total Page:16

File Type:pdf, Size:1020Kb

(1915-2014) to Permafrost Science in Canada Proceedings of a Symposium to Commemorate the Contributions of Professor J. Ross Mackay (1915-2014) to Permafrost Science in Canada 7th Canadian Permafrost Conference Quebec City, QC 20-23 September 2015 Edited by C.R. Burn Proceedings of a Symposium to Commemorate the Contributions of Professor J. Ross Mackay (1915-2014) to Permafrost Science in Canada 7th Canadian Permafrost Conference Quebec City, QC 20-23 September 2015 Edited by C.R. Burn Introduction th Professor J. Ross Mackay, who passed away in 2014 shortly before his 99 birthday, was an iconoclastic influence on geocryology in Canada and around the world. A symposium to honour his contributions to th rd our field was held at the 7 Canadian Permafrost Conference in Quebec City, 20 – 23 September 2015. th The Permafrost Conference was embedded in the 68 Canadian Geotechnical Conference. This volume is the record of the symposium. Publication of the conference papers as a full Proceedings will occur, we hope, in 2016. A companion memorial to this volume, a special issue of Permafrost and Periglacial Processes, is currently in preparation. The majority of contributors invited to the symposium were Canadians, but a few international colleagues also presented papers that were chosen to represent particular dimensions of Ross’s career. The papers in this volume were prepared following the instructions and review procedures of the Canadian Geotechnical Conference. The conference organizers provided a template for style and a limit of 8 pages. The papers were submitted for review by a committee before acceptance and publication at the meeting. I am most grateful to Professor Richard Fortier for overseeing the review and preparation of the papers. The papers were published on flash drives given to every registrant but were not paginated or indexed. The pagination of the papers is unique to this volume. Otherwise the papers are reproduced as presented, except that errors incurred during production have been corrected, such as omission of diagrams submitted in the original copy. Copyright to each paper rests with the authors. I am grateful to all of the authors for allowing their papers to be included in this collection. The papers have been arranged into four sections, in which they are presented in alphabetical order of the last name of the first author. They represent: (1) reflections on the life and work of Professor Mackay; (2) regional studies on permafrost in Canada; (3) discussion of hydrologic effects; and (4) examinations of problems in geocryology. In addition to these authors, I am most grateful to Professor Antoni Lewkowicz and Dr Jerry Brown who filled spaces in the program that appeared due to emergencies before and during the symposium. The obituary for Dr Mackay published in Arctic is reproduced with kind permission of the Arctic Institute of North America and the journal’s editor, Dr Karen McCullough. Christopher Burn Carleton University Ottawa, ON December 2015 ARCTIC VOL. 68, NO. 1 (MARCH 2015) P. 129 – 131 http://dx.doi.org/10.14430/arctic4464 J. ROSS MACKAY (1915 – 2014) John Ross Mackay, Canada’s pre-eminent authority on per- mafrost, died peacefully in the early morning of 28 October 2014. He was nearly 99 years old. Throughout the geocry- ological community, Ross was known as an exemplary researcher, an audacious feld scientist, and a loyal and friendly man. For more than three decades from the early 1960s, he was acknowledged as Canada’s pre-eminent Arc- tic scientist. His feld research in the western Arctic began in 1951 and continued without interruption from 1954 to 2011, although he offcially “retired” from the University of British Columbia (UBC) in 1981. He published 201 scien- tifc papers and two memoirs in toto, all but 13 as sole or senior author. His work is the benchmark on thermal con- traction cracking in permafrost and on pore-water expul- sion during freezing of sands. The permafrost community thus knows him best for his work on ice wedges and pingos, but his expertise on terrain conditions in the western Arctic J. Ross Mackay on the East Channel of the Mackenzie River, July 2010. was perhaps of more immediate material signifcance. He was told in the 1970s that his work had saved industry two equivalent to his academic research. His brother, Leslie, full years of investigations in preparation for hydrocarbon joined the RCAF, and was lost over the English Channel in development in the region. 1942. He mourned his brother, taken prematurely like so Ross was born in Tamsui, Formosa (now Taiwan), to many others, for the rest of his life. Canadian missionary parents. His family is renowned in Ross joined McGill University as an assistant profes- Taiwan, particularly for the extensive medical and educa- sor in 1946 and at the same time started his PhD research, tional work initiated by Ross’s paternal grandfather, George enrolled at the University of Montreal. His “offce” was a Leslie Mackay, who founded the Presbyterian Church desk in the department library. During the regular session there. Ross’s paternal grandmother, Tiuⁿ Chhang-miâ, was he taught large classes, dominated by veterans, using only a Taiwanese and this, along with his time in Tamsui, gave blackboard and chalk. He then joined the summer school at him a lifelong affnity with the country. When Ross visited Stanstead, QC, where he met V. Stefansson and N.E. Odell. Taiwan, he was treated as an icon, with people, particularly His PhD thesis (1949) was on the regional geography of the nurses-in-training, queuing up to be photographed with lower Ottawa valley, but the major paper that he published him. In Tamsui, where he had developed a fondness for ani- from it is primarily a robust reinterpretation of the existing mals and atlases as a child, he was given the key to the city. theory on the origin of the landscape. As early as 1949, he His paper in Economic Geography (1951) declared “geogra- demonstrated a trademark ability to read the landscape in phy of the Far East” as one of his research interests. historical terms and to set straight the published record. He Ross was sent to school at the Canadian Academy in moved to UBC the same year, where he then remained. He Kobe, Japan, and went on to Clark (BA, 1939) and Bos- was in the offce daily from seven to fve, and nine to fve ton (MA, 1941) universities, where he shone. The Second on Saturdays. There he was a reserved man, but an inspira- World War interrupted his academic career; nevertheless, tion and mentor to colleagues with interests quite different he regarded his military service in 1941 – 46 as his greatest from his own, always considering how their work could be contribution. He enlisted as a gunner (private) in the Royal incorporated into his research. Canadian Artillery, and transferred to the Canadian Intel- Ross began his Arctic research in the Darnley Bay area ligence Corps in 1942. He spent the war breaking Japanese of the western Arctic coast, providing interpretive keys that codes, particularly with respect to routing of messages, were urgently needed by the newly formed federal Geo- serving in Ottawa in the same offce as Diamond Jenness. graphical Branch for aerial photographs, given the recent A formal history of his unit described him quite simply availability of stereoscopic coverage. He was hired for his as “brilliant.” In 1945, an American general told him that stellar reputation and as one of the very few Canadians who his work had saved a division (more than 15 000 men). He had advanced training in physical geography at that time. ended his service with the rank of major, as Commanding He walked south and east from Paulatuk with his assis- Offcer No. 1 Discrimination Unit, Directorate of Military tants J. Keith Fraser, from the Geographical Branch, and Intelligence, Ottawa, having commanded the Intelligence Joe Thrasher, from the community, accompanied by six Unit, No. 1 Canadian Special Wireless Group, Darwin, pack dogs. They had no maps or radios. For navigation, they Australia, in 1945. His subsequent career was founded on relied on the aerial photos, a compass, and Joe’s knowledge the reputation he had acquired in the Intelligence Corps. of the terrain. The journey began a life-long friendship with Ross described his activities in cryptanalysis as generically the people of Paulatuk. It also led to Ross’s frst paper on 130 • OBITUARY Arctic geomorphology, published in 1952. On the journey north from Yellowknife by foat plane, the pilot, Ernie Boffa, had been concerned that the water bodies were still frozen about 200 miles short of their destination, so he turned back and dropped down on a small lake, left Ross and Keith there, and said he would return in a week’s time. Neither Boffa nor Mackay had a map! In 1960, Ross published observations made during that hiatus. The lake now has a permanent name on the maps of Canada. It is called Stopover Lake. During the 1950s, after a season on Cornwallis Island in 1952, Ross began to accumulate feld experience through- out the western Arctic, traveling by boat along the coast east and west of the Mackenzie delta and walking inland. Most of his journeys were by freighter canoe, driven by J. Ross Mackay recording the deformation of an antisyngenetic ice wedge at a 5 or 10 hp motor, and by schooner. He ran feld parties Garry Island, June 1992. for the Geographical Branch, four times with John Stager, usually with someone from the region as guide and assis- feld measurements on the dynamics of thermal-contrac- tant. His published record from the period was dominated tion cracking and ice-wedge polygon development.
Recommended publications
  • Contemporary Periglacial Processes in the Swiss Alps: Seasonal, Inter-Annual and Long-Term Variations
    Permafrost, Phillips, Springman & Arenson (eds) © 2003 Swets & Zeitlinger, Lisse, ISBN 90 5809 582 7 Contemporary periglacial processes in the Swiss Alps: seasonal, inter-annual and long-term variations N. Matsuoka & A. Ikeda Institute of Geoscience, University of Tsukuba, Ibaraki, Japan K. Hirakawa & T. Watanabe Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan ABSTRACT: Comprehensive monitoring of periglacial weathering and mass wasting has been undertaken near the lower limit of the mountain permafrost belt. Seven years of monitoring highlight both seasonal and inter- annual variations. On the seasonal scale, three types of movements are identified: (A) small magnitude events associated with diurnal freeze-thaw cycles, (B) larger events during early seasonal freezing and (C) sporadic events originating from refreezing of meltwater during seasonal thawing. Type A produces pebbles or smaller fragments from rockwalls and shallow (Ͻ10 cm) frost creep on debris slopes. Types B and C are responsible for larger debris production and deeper (Ͻ50 cm) frost creep/gelifluction. Some of these events contribute to perma- nent opening of rock joints and advance of solifluction lobes. Sporadic large boulder falls enhance inter-annual variation in rockwall retreat rates. On some debris slopes, prolonged snow melting occasionally triggers rapid soil flow, which causes inter-annual variation in rates of soil movement. 1 INTRODUCTION 9º40'E 10º00'E Piz Kesch Real-time monitoring of periglacial slope processes is 3418 Switzerland useful to predict ongoing slope instability problems in Inn alpine regions. Such a prediction, however, needs long- Piz d'Err Piz Ot term variations in slope processes caused by climate 3378 3246 Samedan Italia change to be distinguished from inter-annual scale vari- A 30'E 30'E º St.
    [Show full text]
  • Chapter 7 Seasonal Snow Cover, Ice and Permafrost
    I Chapter 7 Seasonal snow cover, ice and permafrost Co-Chairmen: R.B. Street, Canada P.I. Melnikov, USSR Expert contributors: D. Riseborough (Canada); O. Anisimov (USSR); Cheng Guodong (China); V.J. Lunardini (USA); M. Gavrilova (USSR); E.A. Köster (The Netherlands); R.M. Koerner (Canada); M.F. Meier (USA); M. Smith (Canada); H. Baker (Canada); N.A. Grave (USSR); CM. Clapperton (UK); M. Brugman (Canada); S.M. Hodge (USA); L. Menchaca (Mexico); A.S. Judge (Canada); P.G. Quilty (Australia); R.Hansson (Norway); J.A. Heginbottom (Canada); H. Keys (New Zealand); D.A. Etkin (Canada); F.E. Nelson (USA); D.M. Barnett (Canada); B. Fitzharris (New Zealand); I.M. Whillans (USA); A.A. Velichko (USSR); R. Haugen (USA); F. Sayles (USA); Contents 1 Introduction 7-1 2 Environmental impacts 7-2 2.1 Seasonal snow cover 7-2 2.2 Ice sheets and glaciers 7-4 2.3 Permafrost 7-7 2.3.1 Nature, extent and stability of permafrost 7-7 2.3.2 Responses of permafrost to climatic changes 7-10 2.3.2.1 Changes in permafrost distribution 7-12 2.3.2.2 Implications of permafrost degradation 7-14 2.3.3 Gas hydrates and methane 7-15 2.4 Seasonally frozen ground 7-16 3 Socioeconomic consequences 7-16 3.1 Seasonal snow cover 7-16 3.2 Glaciers and ice sheets 7-17 3.3 Permafrost 7-18 3.4 Seasonally frozen ground 7-22 4 Future deliberations 7-22 Tables Table 7.1 Relative extent of terrestrial areas of seasonal snow cover, ice and permafrost (after Washburn, 1980a and Rott, 1983) 7-2 Table 7.2 Characteristics of the Greenland and Antarctic ice sheets (based on Oerlemans and van der Veen, 1984) 7-5 Table 7.3 Effect of terrestrial ice sheets on sea-level, adapted from Workshop on Glaciers, Ice Sheets and Sea Level: Effect of a COylnduced Climatic Change.
    [Show full text]
  • 180 in Siberian Syngenetic Ice-Wedge Complexes
    14C AND 180 IN SIBERIAN SYNGENETIC ICE-WEDGE COMPLEXES YURIJ K. VASIL'CHUK Department of Cryolithology and Glaciology and Laboratory of Regional Engineering Geology, Moscow State University, Vorob'yovy Gory, 119899 Moscow, Russia and The Theoretical Problems Department, Russian Academy of Sciences, Denezhnyi pereulok, 12, 121002 Moscow, Russia and ALLA C. VASIL'CHUK Institute of Cell Biophysics, The Russian Academy of Sciences, 142292, Pushchino Moscow Region, Russia ABSTRACT. We discuss the possibility of dating ice wedges by the radiocarbon method. We show as an example the Seyaha, Kular and Zelyony Mys ice wedge complexes, and investigated various organic materials from permafrost sediments. We show that the reliability of dating 180 variations from ice wedges can be evaluated by comparison of different organic mate- rials from host sediments in the ice wedge cross sections. INTRODUCTION Permafrost covers 60% of the Russian territory and a large part of North America. During the glacial period, almost all of Europe was also covered by permafrost, with temperatures close to the present ones in the north of western Siberia and Yakutia (Vasil'chuk and Vasil'chuk 1995a). That permafrost melted not more than 10,000 yr ago. This enables radiocarbon dating of paleopermafrost sediments from Europe and North America. Hydrogen and oxygen stable isotopes in syngenetic ice wedges of northern Eurasia and North America permafrost zones yield paleoclimatic parameters, such as paleotemperature. The oxygen isotope composition of a recently formed syngenetic ice wedge together with present winter temper- atures of surface air (Vasil'chuk 1991) made it possible to use stable isotope variations in ancient syngenetic ice wedges as a quantitative paleotemperature indicator (to make sure that the same dependence took place in the past).
    [Show full text]
  • Periglacial Processes, Features & Landscape Development 3.1.4.3/4
    Periglacial processes, features & landscape development 3.1.4.3/4 Glacial Systems and landscapes What you need to know Where periglacial landscapes are found and what their key characteristics are The range of processes operating in a periglacial landscape How a range of periglacial landforms develop and what their characteristics are The relationship between process, time, landforms and landscapes in periglacial settings Introduction A periglacial environment used to refer to places which were near to or at the edge of ice sheets and glaciers. However, this has now been changed and refers to areas with permafrost that also experience a seasonal change in temperature, occasionally rising above 0 degrees Celsius. But they are characterised by permanently low temperatures. Location of periglacial areas Due to periglacial environments now referring to places with permafrost as well as edges of glaciers, this can account for one third of the Earth’s surface. Far northern and southern hemisphere regions are classed as containing periglacial areas, particularly in the countries of Canada, USA (Alaska) and Russia. Permafrost is where the soil, rock and moisture content below the surface remains permanently frozen throughout the entire year. It can be subdivided into the following: • Continuous (unbroken stretches of permafrost) • extensive discontinuous (predominantly permafrost with localised melts) • sporadic discontinuous (largely thawed ground with permafrost zones) • isolated (discrete pockets of permafrost) • subsea (permafrost occupying sea bed) Whilst permafrost is not needed in the development of all periglacial landforms, most periglacial regions have permafrost beneath them and it can influence the processes that create the landforms. Many locations within SAMPLEextensive discontinuous and sporadic discontinuous permafrost will thaw in the summer months.
    [Show full text]
  • Frost Heave Due to Ice Lens Formation in Freezing Soils 1
    Nordic Hydrolgy, 26, 1995, 125-146 No pd11 m,ty ix ~rproduredby .my proce\\ w~thoutcomplete leference Frost Heave due to Ice Lens Formation in Freezing Soils 1. Theory and Verification D. Sheng, K. Axelsson and S. Knutsson Department of Civil Engineering, Lulei University of Technology, Sweden A frost heave model which simulates formation of ice lenses is developed for saturated salt-free soils. Quasi-steady state heat and mass flow is considered. Special attention is paid to the transmitted zone, i.e. the frozen fringe. The permeability of the frozen fringe is assumed to vary exponentially as a function of temperature. The rates of water flow in the frozen fringe and in the unfrozen soil are assumed to be constant in space but vary with time. The pore water pres- sure in the frozen fringe is integrated from the Darcy law. The ice pressure in the frozen fringe is detcrmined by the generalized Clapeyron equation. A new ice lens is assumed to form in the liozen fringe when and where the effective stress approaches zero. The neutral stress is determined as a simple function of the un- frozen water content and porosity. The model is implemented on an personal computer. The simulated heave amounts and heaving rates are compared with expcrimental data, which shows that the model generally gives reasonable esti- mation. Introduction The phenomenon of frost heave has been studied both experimentally and theoreti- cally for decades. Experimental observations suggest that frost heave is caused by ice lensing associated with thermally-induced water migration. Water migration can take place at temperatures below the freezing point, by flowing via the unfrozen wa- ter film adsorbed around soil particles.
    [Show full text]
  • Permafrost Soils and Carbon Cycling
    SOIL, 1, 147–171, 2015 www.soil-journal.net/1/147/2015/ doi:10.5194/soil-1-147-2015 SOIL © Author(s) 2015. CC Attribution 3.0 License. Permafrost soils and carbon cycling C. L. Ping1, J. D. Jastrow2, M. T. Jorgenson3, G. J. Michaelson1, and Y. L. Shur4 1Agricultural and Forestry Experiment Station, Palmer Research Center, University of Alaska Fairbanks, 1509 South Georgeson Road, Palmer, AK 99645, USA 2Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA 3Alaska Ecoscience, Fairbanks, AK 99775, USA 4Department of Civil and Environmental Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775, USA Correspondence to: C. L. Ping ([email protected]) Received: 4 October 2014 – Published in SOIL Discuss.: 30 October 2014 Revised: – – Accepted: 24 December 2014 – Published: 5 February 2015 Abstract. Knowledge of soils in the permafrost region has advanced immensely in recent decades, despite the remoteness and inaccessibility of most of the region and the sampling limitations posed by the severe environ- ment. These efforts significantly increased estimates of the amount of organic carbon stored in permafrost-region soils and improved understanding of how pedogenic processes unique to permafrost environments built enor- mous organic carbon stocks during the Quaternary. This knowledge has also called attention to the importance of permafrost-affected soils to the global carbon cycle and the potential vulnerability of the region’s soil or- ganic carbon (SOC) stocks to changing climatic conditions. In this review, we briefly introduce the permafrost characteristics, ice structures, and cryopedogenic processes that shape the development of permafrost-affected soils, and discuss their effects on soil structures and on organic matter distributions within the soil profile.
    [Show full text]
  • Ice Segregation As an Origin for Lenses of Non-Glacial Ice in "Ice-Cemented" Rock Glaciers
    Journal of Glaciology, VoI. 27, No. 97, .g8. ICE SEGREGATION AS AN ORIGIN FOR LENSES OF NON-GLACIAL ICE IN "ICE-CEMENTED" ROCK GLACIERS By WILLIAM J. WAYNE (Department of Geology, University of Nebraska, Lincoln, Nebraska 68588, D.S.A.) 0 ABSTRACT. In order to flow with the gradients observed (100 to 15 ) rock glaciers cannot be simply ice-cemented rock debris, but probably contain masses or lenses of debris-free ice. The nature and origin of the ice in rock glaciers that are in no way connected to ice glaciers has not been adequately explained. Rock glaciers and tal us above them are permeable. Water from snow-melt and rain flows through the lower part of the debris on top of the bedrock floor. In the headward part of a rock glacier, where the total thick­ ness is not great, if this groundwater flow is able to maintain water pressure against the base of an aggrading permafrost, segregation of ice lenses should take place. Ice segregation on a large scale would produce lenses of clear ice of sufficient size to permit the streams or lobes of rock debris to flow with gradients comparable to those of glaciers. It would also account for the substantial loss in volume that takes place when a rock glacier stabilizes and collapses. RESUME. La segregation de la glace a l'origine des lentilles de glace d'origine non glaciaire dans les glaciers rocheux soudis par la glace. Pour qu'ils puissent s'ecouler sur les pentes ou on les observe (100 a 150), les glaciers rocheux ne peuvent pas etre simplement constitues de debris rocheux soudes par la glace, mais contient probablement des blocs ou des lentilles de glace depourvus de sediments.
    [Show full text]
  • Spatial and Temporal Dynamics of Microorganisms Living Along Steep Energy Gradients and Implications for Ecology and Geologic Preservation in the Deep Biosphere
    Spatial and Temporal Dynamics of Microorganisms Living Along Steep Energy Gradients and Implications for Ecology and Geologic Preservation in the Deep Biosphere Thesis by Sean William Alexander Mullin In Partial Fulfillment of the Requirements for the degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2020 (Defended 8 June 2020) ii ã 2020 Sean W. A. Mullin ORCID: 0000-0002-6225-3279 iii What is any man’s discourse to me, if I am not sensible of something in it as steady and cheery as the creak of crickets? In it the woods must be relieved against the sky. Men tire me when I am not constantly greeted and refreshed as by the flux of sparkling streams. Surely joy is the condition of life. Think of the young fry that leap in ponds, the myriads of insects ushered into being on a summer evening, the incessant note of the hyla with which the woods ring in the spring, the nonchalance of the butterfly carrying accident and change painted in a thousand hues upon its wings… —Henry David Thoreau, “Natural History of Massachusetts” iv ACKNOWLEDGEMENTS Seven years is a long time. Beyond four years, the collective memory of a university is misty and gray, and if it were a medieval map, would be marked simply, “Here be dragons.” The number of times I have been mistaken this past year for an aged staff scientist or long-suffering post-doc would be amusing if not for my deepening wrinkles serving to confirm my status as a relative dinosaur. Wrinkles aside, I can happily say that my time spent in the Orphan Lab has been one of tremendous growth and exploration.
    [Show full text]
  • 773593683.Pdf
    LAKE AREA CHANGE IN ALASKAN NATIONAL WILDLIFE REFUGES: MAGNITUDE, MECHANISMS, AND HETEROGENEITY A DISSERTATION Presented to the Faculty of the University of Alaska Fairbanks In Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY By Jennifer Roach, B.S. Fairbanks, Alaska December 2011 iii Abstract The objective of this dissertation was to estimate the magnitude and mechanisms of lake area change in Alaskan National Wildlife Refuges. An efficient and objective approach to classifying lake area from Landsat imagery was developed, tested, and used to estimate lake area trends at multiple spatial and temporal scales for ~23,000 lakes in ten study areas. Seven study areas had long-term declines in lake area and five study areas had recent declines. The mean rate of change across study areas was -1.07% per year for the long-term records and -0.80% per year for the recent records. The presence of net declines in lake area suggests that, while there was substantial among-lake heterogeneity in trends at scales of 3-22 km a dynamic equilibrium in lake area may not be present. Net declines in lake area are consistent with increases in length of the unfrozen season, evapotranspiration, and vegetation expansion. A field comparison of paired decreasing and non-decreasing lakes identified terrestrialization (i.e., expansion of floating mats into open water with a potential trajectory towards peatland development) as the mechanism for lake area reduction in shallow lakes and thermokarst as the mechanism for non-decreasing lake area in deeper lakes. Consistent with this, study areas with non-decreasing trends tended to be associated with fine-grained soils that tend to be more susceptible to thermokarst due to their higher ice content and a larger percentage of lakes in zones with thermokarst features compared to study areas with decreasing trends.
    [Show full text]
  • Master's Thesis in Geography Physical Geography Mesoscale Modelling of Periglacial Landforms in the Circumpolar Arctic Tommi K
    Master’s thesis in Geography Physical Geography Mesoscale modelling of periglacial landforms in the circumpolar Arctic Tommi Kukkonen 2020 Supervisor: Miska Luoto Master’s Programme in Geography University of Helsinki Faculty of Science Department of geosciences and geography P. O. Box 64 (Gustaf Hällströmin katu 2) 00014 University of Helsinki Tiedekunta – Fakultet – Faculty Koulutusohjelma – Utbildningsprogram – Degree programme Faculty of Science Master's Programme in Geography Opintosuunta – Studieinrikting – Study track Physical Geography Tekijä – Författare – Author Tommi Kukkonen Työn nimi – Arbetets titel – Title Mesoscale modelling of periglacial landforms in the circumpolar Arctic Työn laji – Arbetets art – Level Aika – Datum – Month and year Sivumäärä – Sidoantal – Number of pages Master's thesis May 2020 86 pages Tiivistelmä – Referat – Abstract The Arctic is warming with an increased pace, and it can affect ecosystems, infrastructure and communities. By studying periglacial landforms and processes, and using improved methods, more knowledge on these changing environmental conditions and their impacts can be obtained. The aim of this thesis is to map studied landforms and predict their probability of occurrence in the circumpolar region utilizing different modelling methods. Periglacial environments occur in high latitudes and other cold regions. These environments host permafrost, which is frozen ground and responds effectively to climate warming, and underlays areas that host many landform types. Therefore, landform monitoring and modelling in permafrost regions under changing climate can provide information about the ongoing changes in the Arctic and landform distributions. Here four landform/process types were mapped and studied: patterned ground, pingos, thermokarst activity and solifluction. The study consisted of 10 study areas across the circumpolar arctic that were mapped for their landforms.
    [Show full text]
  • PERMAFROST Seventh International Conference June 23-27, 1998
    PERMAFROST Seventh International Conference June 23-27, 1998 Program, Abstracts, Reports of the International Permafrost Association Yellowknife, Canada Editors: Antoni G. Lewkowicz Michel Allard Acknowledgments We are grateful to Shawne Clarke and Steve Kokelj, University of Ottawa and Laurent Desrochers and Caroline Lavoie, Universite Laval, for their hard work through the various stages of the production of this volume. iv The 7th International Permafrost Conference Preface This volume comprises the Conference Program, short abstracts, extended abstracts and reports of the International Permafrost Association. The technical portion of the Conference Program includes two Plenary sessions, two extensive Poster sessions and 22 Oral sessions. To fit all of these activities into the time available, three concurrent sessions were necessary for much of the conference. The 59 extended abstracts were submitted by graduate students and other authors whowished to present posters at the Conference and publish a summary of their research endeavours. These extended abstracts were edited but not reviewed. Both the short and extended abstracts are organized alphabetically in this volume by senior author. The reports of the Secretary General and the Working Groups of the International Permafrost Association, found in the last part of this volume, cover the period since the Sixth International Permafrost Conference in Beijing. The latter were prepared by various members of the Working Groups and describe meetings organized, publications produced, international collaboration and plans for the future. Some of these Working Groups will be renewed in Yellowknife while others have completed the tasks for which they were created. All Working Groups will report orally at the second plenary session.
    [Show full text]
  • Organic Carbon Characteristics in Ice-Rich Permafrost in Alas and Yedoma Deposits, Central Yakutia, Siberia” by Torben Windirsch Et Al
    Biogeosciences Discuss., https://doi.org/10.5194/bg-2019-470-RC1, 2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Interactive comment on “Organic Carbon Characteristics in Ice-rich Permafrost in Alas and Yedoma Deposits, Central Yakutia, Siberia” by Torben Windirsch et al. Anonymous Referee #1 Received and published: 27 January 2020 The paper “Organic Carbon Characteristics in Ice-rich Permafrost in Alas and Yedoma Deposits, Central Yakutia, Siberia” by Windirsch et al. reports detailed analyses on carbon and ice contents, stable water isotopes, soil grain size distribution, and age estimates for two long ground profiles in the Central Yakutia, Russia. The presented materials are rare and highly valuable to understand landscape development and con- tents in the permafrost of the Eastern Siberia. Although I expect this paper to be finally published in Biogeosciece, the authors have not fully utilized, described, and discussed the data presented. The importance of this paper is the rareness of the sample core. I encourage the authors to enrich their descriptions about each core unit as a valuable drilling log of a permafrost region. Some portions in Discussion are C1 not logically constructed. For the main datasets of stable water isotopes and carbon parameters, a more in-depth and quantitative discussion is anticipated. Although the authors want to focus on the organic carbon characteristics as indicated in the title, more comprehensive discussion and interpretation must be done using available water geochemistry, cryostratigraphy, grain size distribution, magnetic susceptibility, etc. The usage of references or previous studies is poor and is often not clear or inappropriate.
    [Show full text]