Understanding Feedback Loops
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Climate Change and Human Health: Risks and Responses
Climate change and human health RISKS AND RESPONSES Editors A.J. McMichael The Australian National University, Canberra, Australia D.H. Campbell-Lendrum London School of Hygiene and Tropical Medicine, London, United Kingdom C.F. Corvalán World Health Organization, Geneva, Switzerland K.L. Ebi World Health Organization Regional Office for Europe, European Centre for Environment and Health, Rome, Italy A.K. Githeko Kenya Medical Research Institute, Kisumu, Kenya J.D. Scheraga US Environmental Protection Agency, Washington, DC, USA A. Woodward University of Otago, Wellington, New Zealand WORLD HEALTH ORGANIZATION GENEVA 2003 WHO Library Cataloguing-in-Publication Data Climate change and human health : risks and responses / editors : A. J. McMichael . [et al.] 1.Climate 2.Greenhouse effect 3.Natural disasters 4.Disease transmission 5.Ultraviolet rays—adverse effects 6.Risk assessment I.McMichael, Anthony J. ISBN 92 4 156248 X (NLM classification: WA 30) ©World Health Organization 2003 All rights reserved. Publications of the World Health Organization can be obtained from Marketing and Dis- semination, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: [email protected]). Requests for permission to reproduce or translate WHO publications—whether for sale or for noncommercial distribution—should be addressed to Publications, at the above address (fax: +41 22 791 4806; email: [email protected]). The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. -
What Is a Complex Adaptive System?
PROJECT GUTS What is a Complex Adaptive System? Introduction During the last three decades a leap has been made from the application of computing to help scientists ‘do’ science to the integration of computer science concepts, tools and theorems into the very fabric of science. The modeling of complex adaptive systems (CAS) is an example of such an integration of computer science into the very fabric of science; models of complex systems are used to understand, predict and prevent the most daunting problems we face today; issues such as climate change, loss of biodiversity, energy consumption and virulent disease affect us all. The study of complex adaptive systems, has come to be seen as a scientific frontier, and an increasing ability to interact systematically with highly complex systems that transcend separate disciplines will have a profound affect on future science, engineering and industry as well as in the management of our planet’s resources (Emmott et al., 2006). The name itself, “complex adaptive systems” conjures up images of complicated ideas that might be too difficult for a novice to understand. Instead, the study of CAS does exactly the opposite; it creates a unified method of studying disparate systems that elucidates the processes by which they operate. A complex system is simply a system in which many independent elements or agents interact, leading to emergent outcomes that are often difficult (or impossible) to predict simply by looking at the individual interactions. The “complex” part of CAS refers in fact to the vast interconnectedness of these systems. Using the principles of CAS to study these topics as related disciplines that can be better understood through the application of models, rather than a disparate collection of facts can strengthen learners’ understanding of these topics and prepare them to understand other systems by applying similar methods of analysis (Emmott et al., 2006). -
Lecture 21: Glaciers and Paleoclimate Read: Chapter 15 Homework Due Thursday Nov
Learning Objectives (LO) Lecture 21: Glaciers and Paleoclimate Read: Chapter 15 Homework due Thursday Nov. 12 What we’ll learn today:! 1. 1. Glaciers and where they occur! 2. 2. Compare depositional and erosional features of glaciers! 3. 3. Earth-Sun orbital parameters, relevance to interglacial periods ! A glacier is a river of ice. Glaciers can range in size from: 100s of m (mountain glaciers) to 100s of km (continental ice sheets) Most glaciers are 1000s to 100,000s of years old! The Snowline is the lowest elevation of a perennial (2 yrs) snow field. Glaciers can only form above the snowline, where snow does not completely melt in the summer. Requirements: Cold temperatures Polar latitudes or high elevations Sufficient snow Flat area for snow to accumulate Permafrost is permanently frozen soil beneath a seasonal active layer that supports plant life Glaciers are made of compressed, recrystallized snow. Snow buildup in the zone of accumulation flows downhill into the zone of wastage. Glacier-Covered Areas Glacier Coverage (km2) No glaciers in Australia! 160,000 glaciers total 47 countries have glaciers 94% of Earth’s ice is in Greenland and Antarctica Mountain Glaciers are Retreating Worldwide The Antarctic Ice Sheet The Greenland Ice Sheet Glaciers flow downhill through ductile (plastic) deformation & by basal sliding. Brittle deformation near the surface makes cracks, or crevasses. Antarctic ice sheet: ductile flow extends into the ocean to form an ice shelf. Wilkins Ice shelf Breakup http://www.youtube.com/watch?v=XUltAHerfpk The Greenland Ice Sheet has fewer and smaller ice shelves. Erosional Features Unique erosional landforms remain after glaciers melt. -
Cryosphere: a Kingdom of Anomalies and Diversity
Atmos. Chem. Phys., 18, 6535–6542, 2018 https://doi.org/10.5194/acp-18-6535-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Cryosphere: a kingdom of anomalies and diversity Vladimir Melnikov1,2,3, Viktor Gennadinik1, Markku Kulmala1,4, Hanna K. Lappalainen1,4,5, Tuukka Petäjä1,4, and Sergej Zilitinkevich1,4,5,6,7,8 1Institute of Cryology, Tyumen State University, Tyumen, Russia 2Industrial University of Tyumen, Tyumen, Russia 3Earth Cryosphere Institute, Tyumen Scientific Center SB RAS, Tyumen, Russia 4Institute for Atmospheric and Earth System Research (INAR), Physics, Faculty of Science, University of Helsinki, Helsinki, Finland 5Finnish Meteorological Institute, Helsinki, Finland 6Faculty of Radio-Physics, University of Nizhny Novgorod, Nizhny Novgorod, Russia 7Faculty of Geography, University of Moscow, Moscow, Russia 8Institute of Geography, Russian Academy of Sciences, Moscow, Russia Correspondence: Hanna K. Lappalainen (hanna.k.lappalainen@helsinki.fi) Received: 17 November 2017 – Discussion started: 12 January 2018 Revised: 20 March 2018 – Accepted: 26 March 2018 – Published: 8 May 2018 Abstract. The cryosphere of the Earth overlaps with the 1 Introduction atmosphere, hydrosphere and lithosphere over vast areas ◦ with temperatures below 0 C and pronounced H2O phase changes. In spite of its strong variability in space and time, Nowadays the Earth system is facing the so-called “Grand the cryosphere plays the role of a global thermostat, keeping Challenges”. The rapidly growing population needs fresh air the thermal regime on the Earth within rather narrow limits, and water, more food and more energy. Thus humankind suf- affording continuation of the conditions needed for the main- fers from climate change, deterioration of the air, water and tenance of life. -
Statement Climate Change Greenhouse Effect
Western Region Technical Attachment No. 91-07 February 19, 1991 STATEMENT ON CLIMATE. CHANGE AND THE GREENHOUSE EFFECT STATEMENT ON CLIMATE CHANGE AND THE GREENHOUSE EFFECT by REGIONAL CLIMATE CENTERS High Plains Climate Center· University of Nebraska Midwestern Climate Center • Illinois State Water Survey Northeast Regional Climate Center - Cornell University Southern Regional Climate Center • Louisiana State University Southeastern Regional Climate Center • South Carolina Water Commission "'estern Regional Climate Center - Desert Research Institute March 1990 STATEMENT ON CLIMATE CHANGE AND THE GREENHOUSE EFFECT by Regional Climate Centers The Issue Many scientists have issued claims of future global climate changes towards warmer conditions as a result of the ever increasing global release of Carbon Dioxide (C02) and other trace gases from the burning of fossil fuels and from deforestation. The nation experienced an unexpected and severe drought in 1988 which continued through 1989 in parts of the western United States.Is there a connection between these two atmospheric issues? Was the highly unusual 1988-89 drought the first symptom of the climate change atmospheric scientists had been talking about for the past 10 years? Most of the scientific community say "no." The 1988 drought was probably not tied to the ever increasing atmospheric burden of our waste gases. The 1988 drought fits within the historical range of climatic extremes over the past 100 years. Regardless, global climate. change due to the greenhouse effect is an issue of growing national and international concern. It joins the acid rain and ozone layer issues as major atmospheric problems arising primarily from human activities. The term "Greenhouse Effect" derives from the loose analogy between the behavior of the absorbing trace gases in the atmosphere and the window glass in a greenhouse. -
Phytoplankton As Key Mediators of the Biological Carbon Pump: Their Responses to a Changing Climate
sustainability Review Phytoplankton as Key Mediators of the Biological Carbon Pump: Their Responses to a Changing Climate Samarpita Basu * ID and Katherine R. M. Mackey Earth System Science, University of California Irvine, Irvine, CA 92697, USA; [email protected] * Correspondence: [email protected] Received: 7 January 2018; Accepted: 12 March 2018; Published: 19 March 2018 Abstract: The world’s oceans are a major sink for atmospheric carbon dioxide (CO2). The biological carbon pump plays a vital role in the net transfer of CO2 from the atmosphere to the oceans and then to the sediments, subsequently maintaining atmospheric CO2 at significantly lower levels than would be the case if it did not exist. The efficiency of the biological pump is a function of phytoplankton physiology and community structure, which are in turn governed by the physical and chemical conditions of the ocean. However, only a few studies have focused on the importance of phytoplankton community structure to the biological pump. Because global change is expected to influence carbon and nutrient availability, temperature and light (via stratification), an improved understanding of how phytoplankton community size structure will respond in the future is required to gain insight into the biological pump and the ability of the ocean to act as a long-term sink for atmospheric CO2. This review article aims to explore the potential impacts of predicted changes in global temperature and the carbonate system on phytoplankton cell size, species and elemental composition, so as to shed light on the ability of the biological pump to sequester carbon in the future ocean. -
Agriculture, Forestry, and Other Human Activities
4 Agriculture, Forestry, and Other Human Activities CO-CHAIRS D. Kupfer (Germany, Fed. Rep.) R. Karimanzira (Zimbabwe) CONTENTS AGRICULTURE, FORESTRY, AND OTHER HUMAN ACTIVITIES EXECUTIVE SUMMARY 77 4.1 INTRODUCTION 85 4.2 FOREST RESPONSE STRATEGIES 87 4.2.1 Special Issues on Boreal Forests 90 4.2.1.1 Introduction 90 4.2.1.2 Carbon Sinks of the Boreal Region 90 4.2.1.3 Consequences of Climate Change on Emissions 90 4.2.1.4 Possibilities to Refix Carbon Dioxide: A Case Study 91 4.2.1.5 Measures and Policy Options 91 4.2.1.5.1 Forest Protection 92 4.2.1.5.2 Forest Management 92 4.2.1.5.3 End Uses and Biomass Conversion 92 4.2.2 Special Issues on Temperate Forests 92 4.2.2.1 Greenhouse Gas Emissions from Temperate Forests 92 4.2.2.2 Global Warming: Impacts and Effects on Temperate Forests 93 4.2.2.3 Costs of Forestry Countermeasures 93 4.2.2.4 Constraints on Forestry Measures 94 4.2.3 Special Issues on Tropical Forests 94 4.2.3.1 Introduction to Tropical Deforestation and Climatic Concerns 94 4.2.3.2 Forest Carbon Pools and Forest Cover Statistics 94 4.2.3.3 Estimates of Current Rates of Forest Loss 94 4.2.3.4 Patterns and Causes of Deforestation 95 4.2.3.5 Estimates of Current Emissions from Forest Land Clearing 97 4.2.3.6 Estimates of Future Forest Loss and Emissions 98 4.2.3.7 Strategies to Reduce Emissions: Types of Response Options 99 4.2.3.8 Policy Options 103 75 76 IPCC RESPONSE STRATEGIES WORKING GROUP REPORTS 4.3 AGRICULTURE RESPONSE STRATEGIES 105 4.3.1 Summary of Agricultural Emissions of Greenhouse Gases 105 4.3.2 Measures and -
GSA TODAY • Southeastern Section Meeting, P
Vol. 5, No. 1 January 1995 INSIDE • 1995 GeoVentures, p. 4 • Environmental Education, p. 9 GSA TODAY • Southeastern Section Meeting, p. 15 A Publication of the Geological Society of America • North-Central–South-Central Section Meeting, p. 18 Stability or Instability of Antarctic Ice Sheets During Warm Climates of the Pliocene? James P. Kennett Marine Science Institute and Department of Geological Sciences, University of California Santa Barbara, CA 93106 David A. Hodell Department of Geology, University of Florida, Gainesville, FL 32611 ABSTRACT to the south from warmer, less nutrient- rich Subantarctic surface water. Up- During the Pliocene between welling of deep water in the circum- ~5 and 3 Ma, polar ice sheets were Antarctic links the mean chemical restricted to Antarctica, and climate composition of ocean deep water with was at times significantly warmer the atmosphere through gas exchange than now. Debate on whether the (Toggweiler and Sarmiento, 1985). Antarctic ice sheets and climate sys- The evolution of the Antarctic cryo- tem withstood this warmth with sphere-ocean system has profoundly relatively little change (stability influenced global climate, sea-level his- hypothesis) or whether much of the tory, Earth’s heat budget, atmospheric ice sheet disappeared (deglaciation composition and circulation, thermo- hypothesis) is ongoing. Paleoclimatic haline circulation, and the develop- data from high-latitude deep-sea sed- ment of Antarctic biota. iments strongly support the stability Given current concern about possi- hypothesis. Oxygen isotopic data ble global greenhouse warming, under- indicate that average sea-surface standing the history of the Antarctic temperatures in the Southern Ocean ocean-cryosphere system is important could not have increased by more for assessing future response of the Figure 1. -
Glacier (And Ice Sheet) Mass Balance
Glacier (and ice sheet) Mass Balance The long-term average position of the highest (late summer) firn line ! is termed the Equilibrium Line Altitude (ELA) Firn is old snow How an ice sheet works (roughly): Accumulation zone ablation zone ice land ocean • Net accumulation creates surface slope Why is the NH insolation important for global ice• sheetSurface advance slope causes (Milankovitch ice to flow towards theory)? edges • Accumulation (and mass flow) is balanced by ablation and/or calving Why focus on summertime? Ice sheets are very sensitive to Normal summertime temperatures! • Ice sheet has parabolic shape. • line represents melt zone • small warming increases melt zone (horizontal area) a lot because of shape! Slightly warmer Influence of shape Warmer climate freezing line Normal freezing line ground Furthermore temperature has a powerful influence on melting rate Temperature and Ice Mass Balance Summer Temperature main factor determining ice growth e.g., a warming will Expand ablation area, lengthen melt season, increase the melt rate, and increase proportion of precip falling as rain It may also bring more precip to the region Since ablation rate increases rapidly with increasing temperature – Summer melting controls ice sheet fate* – Orbital timescales - Summer insolation must control ice sheet growth *Not true for Antarctica in near term though, where it ʼs too cold to melt much at surface Temperature and Ice Mass Balance Rule of thumb is that 1C warming causes an additional 1m of melt (see slope of ablation curve at right) -
The Effects of Feedback Interventions on Performance: a Historical Review, a Meta-Analysis, and a Preliminary Feedback Intervention Theory
Psychological Bulletin Copyright 1996 by the American Psychological Association, Inc. 1996, Vol. II9, No. 2, 254-284 0033-2909/96/S3.00 The Effects of Feedback Interventions on Performance: A Historical Review, a Meta-Analysis, and a Preliminary Feedback Intervention Theory Avraham N. Kluger Angelo DeNisi The Hebrew University of Jerusalem Rutgers University Since the beginning of the century, feedback interventions (FIs) produced negative—but largely ignored—effects on performance. A meta-analysis (607 effect sizes; 23,663 observations) suggests that FIs improved performance on average (d = .41) but that over '/3 of the FIs decreased perfor- mance. This finding cannot be explained by sampling error, feedback sign, or existing theories. The authors proposed a preliminary FI theory (FIT) and tested it with moderator analyses. The central assumption of FIT is that FIs change the locus of attention among 3 general and hierarchically organized levels of control: task learning, task motivation, and meta-tasks (including self-related) processes. The results suggest that FI effectiveness decreases as attention moves up the hierarchy closer to the self and away from the task. These findings are further moderated by task characteristics that are still poorly understood. To relate feedback directly to behavior is very confusing. Results able has been historically disregarded by most FI researchers. This are contradictory and seldom straight-forward. (Ilgen, Fisher, & disregard has led to a widely shared assumption that FIs consis- Taylor, 1979, p. 368) tently improve performance. Fortunately, several FI researchers The effects of manipulation of KR [knowledge of results] on motor (see epigraphs) have recently recognized that FIs have highly vari- learning. -
Causes of Sea Level Rise
FACT SHEET Causes of Sea OUR COASTAL COMMUNITIES AT RISK Level Rise What the Science Tells Us HIGHLIGHTS From the rocky shoreline of Maine to the busy trading port of New Orleans, from Roughly a third of the nation’s population historic Golden Gate Park in San Francisco to the golden sands of Miami Beach, lives in coastal counties. Several million our coasts are an integral part of American life. Where the sea meets land sit some of our most densely populated cities, most popular tourist destinations, bountiful of those live at elevations that could be fisheries, unique natural landscapes, strategic military bases, financial centers, and flooded by rising seas this century, scientific beaches and boardwalks where memories are created. Yet many of these iconic projections show. These cities and towns— places face a growing risk from sea level rise. home to tourist destinations, fisheries, Global sea level is rising—and at an accelerating rate—largely in response to natural landscapes, military bases, financial global warming. The global average rise has been about eight inches since the centers, and beaches and boardwalks— Industrial Revolution. However, many U.S. cities have seen much higher increases in sea level (NOAA 2012a; NOAA 2012b). Portions of the East and Gulf coasts face a growing risk from sea level rise. have faced some of the world’s fastest rates of sea level rise (NOAA 2012b). These trends have contributed to loss of life, billions of dollars in damage to coastal The choices we make today are critical property and infrastructure, massive taxpayer funding for recovery and rebuild- to protecting coastal communities. -
Global Warming Impacts on Severe Drought Characteristics in Asia Monsoon Region
water Article Global Warming Impacts on Severe Drought Characteristics in Asia Monsoon Region Jeong-Bae Kim , Jae-Min So and Deg-Hyo Bae * Department of Civil & Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-Gu, Seoul 05006, Korea; [email protected] (J.-B.K.); [email protected] (J.-M.S.) * Correspondence: [email protected]; Tel.: +82-2-3408-3814 Received: 2 April 2020; Accepted: 7 May 2020; Published: 12 May 2020 Abstract: Climate change influences the changes in drought features. This study assesses the changes in severe drought characteristics over the Asian monsoon region responding to 1.5 and 2.0 ◦C of global average temperature increases above preindustrial levels. Based on the selected 5 global climate models, the drought characteristics are analyzed according to different regional climate zones using the standardized precipitation index. Under global warming, the severity and frequency of severe drought (i.e., SPI < 1.5) are modulated by the changes in seasonal and regional precipitation − features regardless of the region. Due to the different regional change trends, global warming is likely to aggravate (or alleviate) severe drought in warm (or dry/cold) climate zones. For seasonal analysis, the ranges of changes in drought severity (and frequency) are 11.5%~6.1% (and 57.1%~23.2%) − − under 1.5 and 2.0 ◦C of warming compared to reference condition. The significant decreases in drought frequency are indicated in all climate zones due to the increasing precipitation tendency. In general, drought features under global warming closely tend to be affected by the changes in the amount of precipitation as well as the changes in dry spell length.