10. MULTIPLE INFLUENCES INTERACT TO CAUSE IMPACTS TO PEOPLE AND

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2 10. MULTIPLE INFLUENCES INTERACT TO CAUSE IMPACTS TO PEOPLE AND ECOSYSTEMS BEYOND THOSE EXPECTED FROM CLIMATE CHANGE ALONE. Wind, Rivers, and Ocean Currents Transport Contaminants to the Arctic Climate change in the Arctic is taking place in the context of many other changes, such as chemical pollution, increased ultraviolet radiation, and habitat destruction. Societal changes include a growing population, increasing access to Arctic lands, technological innovations, trade liberalization, urbanization, self-determination movements, increasing tourism, and more. All of these changes are interrelated and the consequences of these phenomena will depend largely on interactions among them. Some of these changes will exacerbate impacts due to climate change while others alleviate impacts. Some changes will improve peoples ability to adapt to climate change while others hinder adaptive capacity. The degree to which people are resilient or vulnerable to climate change depends on the cumulative stresses to which they are subject as well as their capacity to adapt to these changes. Adaptive capacity is greatly affected by political, legal, economic, social, and other factors. Responses to environmental changes are multi-dimensional. They include adjustments in hunting, herding, and fishing practices as well as alterations in the political, cultural, and spiritual aspects of life. Adaptation can involve changes in knowledge and how it is used, for example, using newfound knowledge of weather and climate patterns. Arctic people can alter their hunting and herding grounds and the species they pursue, and build new partnerships between federal governments and indigenous peoples governments and organizations. Which environmental changes create the greatest stresses varies greatly among Arctic communities. For example, threats to human health from persistent organic pollutants (POPs), and the reduction of sea ice are extremely serious for Inuit in northern Canada and western Greenland, but not as important to Saami in northern Norway, Sweden, and Finland. For the Saami, freezing rain that coats reindeer forage with ice is of great concern, as is encroachment on grazing lands by roads, and political changes that have affected borders with Finland and Russia, resulting in the loss of traditional pastures. 112

3 KEY FINDING #10 Climate change and contaminants Contaminants including POPs and heavy metals transported to the Arctic from other regions are among the major environmental stresses that interact with climate change. Certain Arctic animal species, particularly those at the upper end of the marine food chain, carry high levels of POPs, such as DDT and PCBs. Global use of these chemicals peaked in the 1960s and 70s and their manufacture has since been banned in most countries. However, pollutants emitted prior to these controls persist in the environment and are transported, primarily by air currents, from industrial and agricultural sources in the mid-latitudes to the Arctic where they condense out of the air onto particles or snowflakes or directly onto Earth's surface. Moving up the food chain, POPs become more concentrated, resulting in high levels in polar bear, arctic fox, and various seals, whales, fish, marine birds, and birds of prey. Arctic people who eat these species are thus exposed to potentially harmful levels of these pollutants. Mercury is the heavy metal of greatest concern in parts of the Arctic. Mercury from distant sources is removed from the atmosphere and deposited on snow in the Arctic where it is released to the environment when the snow melts. It thus becomes available in springtime, at the onset of animal and plant reproduction and rapid growth, when life in the Arctic is most vulnerable. Coal burning, waste incineration, and industrial processes are the major sources of global mercury emissions. Current mercury levels pose a health risk to some Arctic people and animals, and mercury levels are still increasing in the region, despite emissions reductions in Europe and North America. Winds carry contaminants, and precipitation deposits pollutants onto the land and sea. Temperature plays a role in determining the distribution of contaminants between air, land, and water. Projected climate change-related alterations in wind patterns, precipitation, and temperature can thus change the routes of contaminant's entry and the locations and amounts of deposition in the Arctic. More extensive melting of multi-year sea ice and glaciers can result in the rapid release of large pulses of pollutants that were captured in the ice over years or decades. KEY FINDING #10 There are several other ways that climate change can alter contaminant pathways into the Arctic. Recent evidence suggests that salmon migrations undergo large, climate-related variations and that Pacific salmon may respond to change by moving northward into Arctic rivers. These salmon accumulate and magnify contaminants in the Pacific Ocean, and transport them into the Arctic. For selected lakes, fish may bring in more persistent organic pollutants (POPs) than atmospheric deposition. Similarly, changing bird migrations have the potential to transport and concentrate contaminants in particular watersheds. For example, Norwegian researchers studying Lake Ellasjoen found that seabirds serve as important pathways for carrying contaminants (in this case POPs) from marine to freshwater environments. Contaminants emitted in northern industrial areas are transported to the Arctic where they may become concentrated as they move up the food chain. 113

4 10. MULTIPLE INFLUENCES INTERACT TO CAUSE IMPACTS TO PEOPLE AND ECOSYSTEMS BEYOND THOSE EXPECTED FROM CLIMATE CHANGE ALONE. Case Study of Interacting Changes: Saami reindeer herders in northern Norway Observed and projected increases in temperature and precipitation and changes in the timing of the seasons affect reindeer herding in numerous ways. Increases in the frequency of rain on snow, and in periods of winter melting, result in the formation of ice crust layers that make forage less accessible. Increasing autumn temperatures might lead to a later start of the period with snow cover. Rising temperatures and precipitation could increase the frequency of snow falling on unfrozen ground. An increased number, density, and distribution of birch trees in grazing areas has already begun to decrease the availability of forage plants for reindeer in winter. Shifts of forest vegetation into tundra areas are likely to further reduce traditional pasture areas. The characteristic seasonal pattern of moving herds between winter and summer pastures reflects the herders knowledge of seasonal changes in the availability of key resources such as forage and water. In the warm winters of the 1930s, for example, when conditions were sometimes difficult owing to heavy precipitation, herds were moved to the coast earlier than normal in the spring. Similarly, the movement of herds from poorer to better grazing areas, including the "trading of good snow" by neighboring herders, reflects thorough knowledge of forage conditions. In every case, the success of the herders is contingent upon the freedom to move. "... The world has changed too much now. We can say nature is mixed up now. An additional factor is that reindeer herding is being pressured from different political, social, and economic fronts at all times now. Difficulties are real. A way of living that used to support everything is now changing..." - Veikko Magga, Saami Reindeer Herder Government policies in the past few decades have constrained the ability of Saami reindeer herders to respond to and cope with climate warming and other changes. One stress has come from the encroachment of roads and other infrastructure on traditional reindeer grazing lands (see figures). Another stress comes from conflicting environmental and national objectives. Norway s mountain pastures are an important resource for herders, but their management as pastureland is complicated by the presence of predators such as lynx, wolf, and wolverine. Predators are a major threat to the survival of reindeer calves, with some herds losing over 90% of their calves. Saami herders are limited in their ability to respond to this threat by international commitments to conserve wildlife. 114

5 KEY FINDING #10 Other changes come from laws that emphasize meat production, encouraging active breeders and discouraging small holders. These laws favor larger herds, which have thus increased from around 100 to 700 animals. These laws also favor herds dominated by females and calves (the calves are slaughtered for meat) and have resulted in a change in structure from a traditional herd consisting of about 40% bulls, to herds with only 10% bulls. In traditional Saami herding practices, the bulls are important because their superior abilities to dig through deep or poor quality snow make forage plants available to the entire herd. The reduced proportion of bulls may thus present a growing problem as climate change is projected to make snow conditions more difficult for grazing in many areas. Road Expansion Reduces Reindeer Pasture KEY FINDING #10 Projected development of infrastructure including roads, house, military training areas in the Barents Euro-Arctic region The scenario illustrated here is based on the historical development of infrastructure, distribution and density of the human population, existing infrastructure, known location of oil, gas, mineral and forest resources, distance from coast and vegetation type. The encroachment of roads in Finnmark, in northern Norway, between 1940 and 2000, and the associated loss of reindeer pasture. 115

6 10. MULTIPLE INFLUENCES INTERACT TO CAUSE IMPACTS TO PEOPLE AND ECOSYSTEMS BEYOND THOSE EXPECTED FROM CLIMATE CHANGE ALONE. Human Health Climate change will affect human health in the Arctic. The impacts will differ from place to place due to regional differences in climate change as well as variations in health status and adaptive capacity of different populations. Rural Arctic residents in small, isolated communities with a fragile system of support, little infrastructure, and marginal or non-existent public health systems appear to be most vulnerable. People who depend on subsistence hunting and fishing, especially those who rely on just a few species, will be vulnerable to changes that heavily impact those species (for example, reduced sea ice impacts on ringed seals and polar bears). Age, lifestyle, gender, access to resources, and other factors affect individual and collective adaptive capacity. And the historic ability to move to adapt to changing climatic conditions has been reduced as settlements have become permanent. Failure of Tank Piling Foundation Waste Washed Through Fence by Storm Surge There are likely to be both adverse and beneficial outcomes of climate change on human health in the Arctic. Direct positive impacts could include a reduction in cold-induced injuries such as frostbite and hypothermia and a reduction in cold stress. Death rates are higher in winter than in summer and milder winters in some regions could reduce the number of deaths during winter months. However, the relationship between increased numbers of death and winter weather is difficult to interpret and more complex than the association between illness and death related to high temperatures. For example, many winter deaths are due to respiratory infections such as influenza and it is unclear how influenza transmission would be affected by higher winter temperatures. Direct negative impacts are likely to include increased heat stress and accidents associated with unusual ice and weather conditions. Indirect impacts include effects on diet due to changes in the access to and availability of subsistence foods, increased mental and social stresses related to changes in the environment and lifestyle, potential changes in bacterial and viral proliferation, mosquito-borne disease outbreaks, changes in access to quality drinking water, and illness resulting from sanitation system problems. Indigenous people in some regions of the circumpolar North are reporting incidences of stress related to high temperature extremes not previously experienced. Impacts include respiratory difficulties, which, in turn, can limit individuals' participation in physical activities. However, fewer cold days associated with the warming trend in many regions during the winter are reported to have the positive effect of allowing people to get out more in the winter and alleviating stress related to extreme cold. 116

7 KEY FINDING #10 Contaminants, especially Persistent Organic Pollutants and mercury, are another important threat to human health in the Arctic. Increased stresses on health may arise from interactions between contaminants, increasing UV radiation, and the effects of climate change. Rising temperatures have the potential to increase transfers of contaminants to the Arctic. Climate related changes in fish and wildlife distribution will result in significant changes in individuals access to and the availability of traditional foods, with major health implications. A shift to a more Western diet is known to increase the risks of cancer, diabetes, and cardiovascular diseases among northern populations. Decreases in commercially important species, such as salmon, can create economic hardships and health problems associated with reduced income in small communities. Climate stress and shifting animal populations also create conditions for the spread of infectious diseases in animals that can be transmitted to humans. Above Ground Water and Sewer Utilidor Safe drinking water and proper sanitation are critical in maintaining human health. Sanitation infrastructure includes water treatment and distribution systems, wastewater collection, treatment and disposal facilities, and solid waste collection and disposal. Permafrost thawing, coastal erosion and other climaterelated changes that adversely affect drinking water quality, limit efficient delivery, or cause direct damage to facilities are likely to lead to adverse impacts to human health. Increases in extreme events such as floods, storms, rockslides, and avalanches can be expected to cause an increase in injury and death. In addition to such direct impacts of these events, indirect effects could include impacts on the availability of safe drinking water. Intense rainfall events can also trigger mosquito-borne disease outbreaks, flood-related disasters, and, depending on existing water infrastructure, contamination of the water supply. Mental health is likely to be affected by climate related changes in the Arctic as well. Reduced opportunities for subsistence hunting, fishing, herding, and gathering are likely to cause psychological stresses due to the loss of important cultural activities. Flooding, erosion, and permafrost thawing related to climate change can negatively impact village habitability and infrastructure, and result in population dislocations and community disruption with resultant psychological impacts. West Nile in Canada Map The West Nile encephalitis virus is a recent example of how far and fast a disease can spread once it becomes established in a new region. The West Nile virus can infect many bird and mammal species (including humans) and is transmitted by mosquitoes. It was first identified on the East Coast of North America in 1999 and within three years spread to 43 states and six Canadian provinces by Migratory birds are responsible for its spread to other regions. Mosquitoes spread the virus to other birds (and other animals and humans) within a region. Although the virus originated in tropical Africa, it has adapted to many North American mosquitoes, and so far, to over 110 species of North American birds, some of which migrate to the Arctic. Mosquito species known to transmit the virus are also found in the Arctic. Climate has long posed a barrier for insect-borne diseases but climate change and adaptive disease agents such as the West Nile Virus may favor continued northerly expansion. Some Arctic regions, such as the State of Alaska, have initiated a West Nile Virus surveillance program. 117 KEY FINDING #10

8 CONCLUDING THOUGHTS As the scientific results presented in this report clearly illustrate, climate change presents major and growing concerns to the Arctic region and the entire world. While these concerns are important now, their implications are even more important for the future generations that will inherit the legacy of our current actions or inaction. Strong near-term actions will be required to alter the future path of human-induced warming. The timely and relevant findings of this first Arctic Climate Impact Assessment can provide the scientific basis upon which decision makers can consider, craft, and implement appropriate actions to respond to and address what is likely to be the most important and far-reaching environmental challenge the Arctic people and environment have ever faced. Change Presents Risks and Opportunities As the previous pages have shown, climate change is very likely to result in major environmental changes that will present risks as well as some opportunities across the Arctic region. For example, the large reduction in summer sea ice is one of the most significant changes projected, and it presents both risks and opportunities. Among the clearest risks are threats to the future of several ice-dwelling animals including polar bears, seals, and walrus, and the peoples that depend upon them. A potential opportunity arises for the expansion of marine access to resources, population centers, and distant markets via trans-arctic shipping routes. Numerous other projected changes that present important risks and opportunities emerged from this assessment, and have been summarized in this report. Potential Surprises Some of the most likely climate-related changes in the Arctic environment will have major impacts, such as the decline in sea ice, the increase in coastal erosion, and the thawing of permafrost. In addition, other large concerns emerge from possible outcomes that appear to have only a low likelihood, but the occurrence of which would have very large impacts so-called "surprises." Due to the complexity of the Earth system, it is possible that climate change will evolve differently than the gradually changing scenarios used in this assessment. For example, storm intensity and tracks could change in unforeseen ways or temperatures could rise or fall abruptly due to unexpected disturbances of the world s weather systems. Although such changes in extremes could cause major impacts, very little information is currently available for considering such possibilities. The Beginning of A Process The Arctic Climate Impact Assessment represents the first effort to comprehensively examine climate change and its impacts in the Arctic region. As such, it represents the initiation of a process, rather than simply a report. The ACIA brought together the findings of hundreds of scientists from around the world whose research focuses on the Arctic. It also included the insights of indigenous peoples who have developed deep understandings through their long history of living and gathering knowledge in this region. Linking these scientific and indigenous perspectives is still in its early stages, and clearly has great potential to improve our knowledge of climate change and its impacts. A great deal has been learned from this process and these interactions, though much remains to be studied and better understood. The assessment process in this region should continue, expanding to include other issues of importance to Arctic residents as well as to the wider world. 118

9 As a starting point, the ACIA underscores the need for future assessments to be even more comprehensive, taking into consideration not only the impacts of climate change and ultraviolet radiation, but also the potential influences of the many other stresses that impact society and natural systems. It is the sum of all of these stresses, as well as their interactions, that combine to impact society and natural ecosystems. In addition, the various factors that affect people s ability to adapt must also be considered in assessing how resilient or vulnerable they might be to particular impacts of climate change and other stresses. This assessment took the initial steps of a few such analyses, looking at the complex of influences that combine to affect the vulnerability of particular communities to climate change and its impacts. Many more such locally based studies will be required in the ongoing attempt to better understand and respond to the impacts of climate change and other influences. Trends are not destiny. Rene Dubos The need for much more integration across the usual scientific disciplines is also underscored by this assessment. The many interactions between ecosystems on land, and in freshwater and marine environments are one example; interactions between vegetation and changes in permafrost are another. Scientific research does not often fully represent such interdisciplinary interactions, and impact assessments point squarely to the need for investigation to assess the practical outcomes of climate change for people and the environment. Like the multiple stress problem, this interdisciplinary issue calls for more locally based research to bring the scale of the problem down to a size with which residents can identify and from which they can learn about impacts that affect their lives. This assessment has built on the substance and conclusions of the assessments prepared by the Intergovernmental Panel on Climate Change (IPCC), which provide the world s most authoritative information regarding global climate change and its impacts. The IPCC periodically conducts assessments of the science of global climate change, its impacts, and response options. IPCC released its most recent report, the Third Assessment Report, in The next IPCC assessment is now in the early stages of development. Just as the ACIA has built on IPCC s past findings, the next IPCC report will build on ACIA s findings with regard to the Arctic, doing so in a way that adds the global context. An International Polar Year (IPY), now being planned by the world s scientific community for 2007/8 will provide a special opportunity to focus research attention on climate change and other important issues in the polar regions. The first and second IPYs in 1882/3 and 1932/3, and their expansion into the International Geophysical Year in 1957/8, involved establishing basic research stations, taking auroral and magnetic field measurements, and the like. One of the primary goals already set for the upcoming IPY will be to study and evaluate present and future climate change in the polar regions and to evaluate the global -scale impacts of the changes. All scientific studies indicate that human-induced changes in climate are very likely to be larger in the Arctic than anywhere else on Earth. As a consequence, the changes in Arctic landscapes, communities, and unique features that have already begun to appear, provide an early indication for the rest of the world of the environmental and societal significance of global climate warming. As this report clearly illustrates, changes in climate and their impacts in the Arctic are already being widely noticed and felt, and are projected to be become much larger as we progress through this century. Climate change thus deserves and requires urgent attention by decision makers and the public worldwide. 119