TABLE OF CONTENTS

I. INTRODUCTION

II. SOME RISK FACTORS FOR THE WORLD GEOPOLITICAL STABILITY

III. CLIMATE CHANGE: A LONG-TERM THREAT?

IV. CLIMATE CHANGES AND ARCTIC WARMING

V. THE INTENSIFICATION OF WARMING IN THE ARCTIC DURING THE 21ST CENTURY

VI. ABRUPT CLIMATE CHANGES: THE WEAKENING OF OCEAN CIRCULATION IN THE NORTH ATLANTIC REGION

VII. CONCLUSION: THE NEED FOR A BETTER UNDERSTANDING OF CHALLENGES TO NATO SECURITY INITIATED BY ABRUPT CLIMATE CHANGES

I. INTRODUCTION

1. Today, when we speak of security we do so with a vocabulary considerably different from that used during the Cold War.  We no longer speak of containment, mutual assured destruction, super power rivalry, or bloc interests.  These were the organizing concepts and descriptors of an era appreciably different from the one in which we now find ourselves.
  
2. While the previous period was more stable it was also more dangerous; dangerous in the sense that a nuclear exchange between the superpowers would have meant devastation on a global, if not permanent, basis.  More stable in the sense that the strategic environment was more ordered; everyone knew to which side they belonged and client states were kept in check by their patrons. 
  
3. Now we are confronted by a strategic environment less dangerous but far more unstable.  We are confounded by failed states, international terrorism, tribal conflict, child warriors, trafficking in human beings and transnational criminal organisations.  The challenges to our security and well-being are multi-faceted. They are reflective of Nietzsche's aphorism that "[...] madness is rare in individuals but in groups, parties, nations and ages it is the rule."

4. In coming to cope with these challenges we have adopted a discourse informed by a broader and subtler set of concepts than previously possible.  We speak of human security, capacity building, the sanctity of the individual, multilateralism, and the need to hold the authority of states themselves accountable. 

5. We no longer accept the notion that the pursuit of genuine security for human beings, as individuals, is necessarily subversive of the foundations of international society.  Intervention in the behaviour of states to protect individuals is now deemed an accepted principle of international relations.  Indeed, the Rwanda genocide that happened 10 years ago has taught us that it can, at times, be an obligation.  These views entail far more than the musings of disaffected intellectuals or naïve nirvanists.  They are attempts to come to terms with a reality we do not fully comprehend nor feel entirely comfortable with.  What we are certain of is that today "security" means coming to terms with forms of domination and insecurities that had long been ignored or sacrificed on the altar of realpolitik. 

6. The primacy of the state in strategic thinking permitted a gap to develop between the meanings of the term security as applied to individuals and its meaning for the state.  For security to make sense at the international level it must make sense at the basic level of the individual human being.  Thus, when attempting to understand the complexities of security threats we need to look for our raw data not only in the perceptions and histories of statesmen and diplomats; we also need to take into account the experiences of those rendered insecure by the present world order.  While we continue to speak of the importance of foreign aid we now also accept the fact that the principle of state sovereignty can be breached in order to save those being victimized by the "state" and its agents.  Human security, first and foremost, entails "physical security" - the basic security of the individual.  Without such security, foreign aid remains little more than a cheap meal on the road to continuing despair. 
 
7. The language of realpolitik is slowly giving way to the more nuanced and humanitarian principles of soft power and human security.  This new lexicon has enabled us to widen our horizons and to put on the table security concerns formerly relegated to subsidiary, if any, relevance.  It is, in part, because of this rethinking that we can seriously ponder the implications of environmental degradation for our long-term "common security" interests.

8. Although our intellectual horizons may be widening, it is important to remember that what we now refer to as non-traditional security threats have always been with us.  Disease, crime, poverty, malnutrition, terrorism, environmental degradation and so on, are not newly found realities.  They have long been part of the human condition.  The fact that we have not adequately dealt with them before is largely due to the paucity of previous theory and its inability to deal with the realities of world politics.  While discomfiting to some, the post-cold war environment, along with its unanswered questions and myriad problems, also offers the hope of new vistas.  What we require to take advantage are the appropriate intellectual constructs to help us find our way through the new labyrinth and the political will to confront and deal with issues when presented.

9. Population growth, migration, resource scarcity and environmental degradation are perceived to have two kinds of security implications.  They may either affect security directly, as in the case of a nuclear accident, or they may cause negative social changes, which in turn decrease security.  A recent example would be the decision of the United States government to define AIDS as a security problem.  What is particularly important is that the foregoing concerns are trans-national and global in nature.  In many instances they cannot be addressed effectively by individual states acting on their own; their management requires international cooperation.  Some of the concerns, like AIDS, are immediate risks while others are risks in the longer term. 

II. SOME RISK FACTORS FOR THE WORLD GEOPOLITICAL STABILITY

10. The World Watch Institute, in its State of the World 2005:  Trends and Facts, identifies the following as increasingly important risk factors:

* Natural Resources:  These are at the core of a number of conflicts.  Non-renewable resources such as oil and minerals fuel geopolitical rivalries, clashes with indigenous peoples, and sometimes finance civil wars.  Disputes also arise over renewable natural resources such as water, arable land, and forests.  The effects of environmental breakdown often reinforce social and economic inequities or deepen ethnic and political fault lines.
* Food Scarcity:  Food scarcity is at the intersection of poverty, water availability, land distribution, and environmental degradation.  About 1.4 billion people, almost all of them in developing countries, confront environmental fragility in the form of arid or marginal land, poor soil quality, and land scarcity.
* Disease:  Disease burdens can, in some cases, be sufficiently severe to undermine economies and threaten social stability.  Infectious diseases and other pathologies are crossing borders with increasing ease.  If the current threat of an avian flu pandemic becomes a reality, it could have catastrophic effects around the world.  For its part, AIDS cripples affected societies at all levels, undermining a state's overall resilience and its ability to govern and provide for basic human needs.
* Lack of Employment, Uncertain Economic Prospects, and Rapid Population Growth:  These make for a potentially volatile mix.  Youth unemployment is skyrocketing to record levels.  And when large numbers of young men feel frustrated in their search for status and livelihood, they can be a destabilizing force if their discontent pushes them into crime or into joining militias or extremist groups.

11. The last risk factor identified by the World Watch Institute is the ecosystem destruction that will be the main topic of this paper.  This and other human actions are setting the stage for more frequent and more devastating natural and public health disasters.  According to many observers, the pace is likely to accelerate as climate change translates into more intense storms, hurricanes, flooding, heat waves, and droughts.  The result may be a growing number of environmental refugees and a proliferation of serious diseases such as malaria.

III. CLIMATE CHANGE: A LONG-TERM THREAT?

12. The atmosphere plays a vital role in maintaining the Earth's temperature at levels which support life on the planet's surface. The mechanism responsible for this is the so-called greenhouse effect, whereby certain components of the atmosphere, known as greenhouse gases, retain heat. The most important greenhouse gases are carbon dioxide (CO2), methane, and nitrous oxide. These are produced by natural processes as well as many human activities, notably the burning of fossil fuels such as coal, oil, and gas; and agricultural activities such as raising cattle and cultivating rice. The existence of the greenhouse effect is indisputable: without it, the Earth would be too cold to inhabit.

13. In recent years, a number of scientific studies have detailed the harmful consequences of climate change caused by an increase of greenhouse gases emissions, not only for the various terrestrial ecosystems, but also for the economies, agriculture and social policies of many countries. The media often report, with pictures and sensationalistic accounts as props, weather catastrophes that are automatically attributed to global warming.

14. Although the scientific basis of the theory of climate change is extremely complex, scientists views are clouded by uncertainty given the many models of weather forecasts, and many interest groups with opposing points of view put serious pressure on political decision-makers to reflect their views in the government policies of numerous countries, one fact remains: since the beginning of the industrial revolution, in the 19th century, the Earth's climate has been warming up and this phenomenon is particularly attributable to humans' industrial activities.  

15. Already, in 1998, the NATO Parliamentary Assembly's Science and Technology Committee had studied this question in a special report and looked at the options available to political decision-makers, in particular the Protocol to the United Nations Framework Convention on Climate Change, to reduce greenhouse gases (the Kyoto Protocol) in order to reduce the effects of temperature increases.1

16.  New data on climate change published in recent years provoked a crisis of conscience and indeed a great uncertainty among scientists and many governments. Until very recently, most of the climatology studies presented their long-term effects in a linear, gradual fashion extending over several decades under the influence of natural and human events. Today, they no longer dismiss the possibility that, beyond a certain threshold that is difficult to determine, the temperature increases could lead to sudden and irreversible climate changes produced by a drop in temperatures in the Northern hemisphere.

17. In 2002, the National Academy for Science produced the following definition of this phenomenon that could produce enormous environmental, economic, political and geostrategic consequences for all the countries of the North Atlantic community:

"Abrupt climate change generally refers to a large shift in climate that persists for years or longer-such as marked changes in average temperature, or altered patterns of storms, floods, or droughts-over a widespread area such as an entire country or continent, that takes place so rapidly and unexpectedly that human or natural systems have difficulty adapting to it. In the context of past abrupt climate change, "rapidly" typically means on the order of a decade."2

18. In 2001, the Intergovernmental Panel on Climate Change (IPCC)-created jointly in 1988 by the World Meteorological Organization and the United Nations Environment Programme-published its Third Assessment Report on climate change.3 The group's mandate is to provide an assessment of the state of knowledge on all aspects of climate change, and in particular the ways in which human activities can both cause such changes and be affected by them.4

19. After presenting various global warming scenarios, the IPCC mentioned that many countries would have to expect increased climatic instability in the 21st century and an increase in the intensity and frequency of weather events such as El Nin?o in the South Pacific. They would also have to expect abrupt changes in certain ecosystems, many of them irreversible.5 Finally, the panel also indicated that the international community could witness a weakening in ocean circulation specifically in the North Atlantic.

20. In 2002, another major study produced by an expert panel, this time for the prestigious National Academy for Science, evoked a similar scenario.6 Based on major paleoclimatic research conducted in recent years, the experts agreed that the climate has sometimes evolved quite quickly, and abruptly, over the past 100 000 years and that such a phenomenon could soon recur in the Northern hemisphere.7 Once again, the report affirmed that the weakening, indeed complete cessation, of ocean circulation in the North Atlantic could have been responsible for these changes.

21. Such a possibility seems to have disturbed American government officials deeply. Indeed, at a time when international terrorism was perceived to be the greatest threat to the United States' national security, the American Department of Defence, in 2004, published a report on the possible effects of an abrupt climate change produced by cooling temperatures in the Northern hemisphere, the regional and international political and economic consequences of such a situation and, finally, its implications for the United States' national security.8 

22. Having said that, before going into greater detail about abrupt climate changes and their consequences for the North Atlantic community, it is important to briefly explain the mechanisms that could produce them. The scientific research in this area tends to show that the warming currently under way in the Artic could be one of the triggers of this phenomenon.

IV.
CLIMATE CHANGES AND ARCTIC WARMING
 
23. In 2001, the IPCC's third report showed that the decade of the 1990s had been the hottest on record since 1861 ? when temperatures in various places around the world were first recorded? and that 1998 had been the hottest year during that same period. These changes did not occur uniformly, however, and varied by region and in different parts of the lower atmosphere. For example, between 1910 and 1945, the warming was concentrated mainly in the North Atlantic region. Then, from 1945 to 1975, the temperatures in that same region, like those in the rest of the Northern hemisphere, cooled slightly, while they were increasing in the Southern hemisphere. The most recent period of warming (1976-1999) affected almost the entire planet, while the greatest increases were recorded in the mid- and high latitudes of the Northern hemisphere. 9

24. To sum up, the IPCC set the worldwide increase in temperature at +0.6 degrees Celsius (°C) throughout the 20th century.10 The report points out that this increase results from rapid growth in greenhouse gases in the atmosphere, particularly CO2. Indeed, recent paleoclimatic research measured the concentrations of CO2 in the atmosphere at 280 parts per million (ppm) for the period between the years 1000 and 1850. In 2000, the rate was 368 ppm, an increase of 31 percent since the middle of the 19th century! The IPCC says, "Today's CO2 concentration has not been exceeded during the past 420,000 years and likely not during the past 20 million years. The rate of increase over the past century is unprecedented, at least during the past 20,000 years."11 Last February, the UK's Institute for Public Policy Research published a study citing 400 ppm as the critical threshold concentration of CO2 beyond which increases in worldwide temperatures could lead to abrupt and in some cases irreversible climate change.  According to this study, this threshold could be reached in the coming decades, causing the average worldwide temperature to increase, at least, by+2oC.12  That being said, although a number of scientists have published various theories in recent years to establish this threshold, no consensus has been reached on this important matter.

25. The IPCC report also states that the majority of the climatic warming caused by CO2 emissions since 1950 was caused by anthropogenic factors, that is, by human activities. And still according to the UN panel, almost 75 percent of these emissions were caused by burning fossil fuels. The rest is attributable essentially to changes in land use, and particularly deforestation in developing countries.13 This warming has had a number of effects on ecosystems, including:

* A rise in sea levels of 1 to 2 millimetres annually during the 20th century, in other words, of 10 to 20 centimetres during this period;14
* an increase in the number of events such as El Nin?o in the South Pacific over the past 30 years, events that last longer and are more intense than in the past;15
* an increase, between 1950 and 1993, of around 0.2°C every decade in the minimum daily surface air temperature measured at night. This is roughly double the rate of increase in maximum daytime temperatures, that is, 0.1°C every decade for the same period;
* a decrease of more than two weeks in the freezing season for lakes and rivers in the Northern hemisphere;16
* a lengthening of the biological growing season of one to four days every decade for the past 40 years in that same region;17
* an increase in precipitation of 0.5 to 1 percent every decade throughout most of the mid- and high latitudes of the Northern hemisphere, compared with only 0.2 to 0.3 percent in the tropical zones;18
* a significant reduction in the number of glaciers in mountains outside the polar regions, particularly in the Alps, in Europe;19 and
* a roughly 10-percent reduction in snow coverage, according to satellite data, since the late 1960s.20

26. As we can see, a number of the above impacts occurred in the Northern hemisphere, particularly in the Arctic region, widely recognized as the habitat of the Inuit and polar bears. The IPCC states: "The Arctic is extremely vulnerable to climate change, and major physical, ecological and economical impacts are expected to appear rapidly. A variety of feedback mechanisms will cause an amplified response, with consequent impacts on other systems and peoples."21 In 2001, the intergovernmental panel put more emphasis on the consequences of global warming in the Arctic than the Antarctic since, apart from a temperature rise in the Antarctic Peninsula, the scientific data available combined with the climatic forecasts for the 21st century seem to indicate that such a phenomenon would occur over a longer period at the South Pole.

27.  In contrast to what scientists have observed in most of the Arctic, the temperature in a number of regions in the Antarctic has not increased in recent decades.  Moreover, no significant changes in the sea ice surface have been recorded since 1978, when reliable satellite measurements began.  According to the IPCC, the total mass of the Antarctic ice cap is expected to increase in the coming decades, but following ongoing warming, it could be reduced significantly, adding a number of meters to the rise in sea level expected in the next 1000 years.

28. Many scientists explain these different forecasts for the two poles by the fact that the majority of the Antarctic ice cap is located on a continent where temperatures rarely rise above freezing and not on the ocean, as at the North Pole, where the temperatures are milder during the summer period, and thus have a greater effect on snow and ice coverage and climate changes.22

29. In November 2004, the Arctic Council-an intergovernmental forum of countries that border the polar region-published a major study conducted over the past four years by over 300 scientists from 15 countries on climate changes' effects on this important and fragile ecosystem.23

30. This study's findings are troubling and confirm some of the IPCC's observations.24 The Arctic is warming up more rapidly than other regions of the world and the effects of that warming will be felt throughout the world in the 21st century. Three reasons explain the Arctic's influence on the world climate. First, because of the significant snow and ice coverage found there, most of the solar energy is reflected back into space, the reverse of what happens in the tropical regions. This phenomenon is called albedo. For example, sea ice reflects almost 90 percent of solar energy. What is more, this ecosystem also plays an important role in ocean circulation in the North Atlantic. Finally, any increase in the temperature of the permafrost which contains methane and any change in the Arctic vegetation combined with a reduction in the snow and ice coverage could reduce the Arctic region's albedo, contribute further to global warming and increase the concentration of greenhouse gases in the atmosphere.  

31. The Arctic Council's study also revealed that the average temperature in that region, despite certain local variations, had increased two times more rapidly than the global average in the past decades. For example, it increased from 3 to 4°C in Alaska and in Western Canada during the past 50 years!25 An important fact to note is that this warming is more marked during the winter season. The scientists explain this unusual, and unprecedented, increase by the increase in greenhouse gases caused mainly by anthropogenic factors.

32. The effect of this marked increase in temperatures combined with other factors such as waves and sea currents was (as can be seen in figures 1 and 2) to reduce the annual average sea ice extent by almost 8 percent, or over one million square kilometres, over the past 30 years, an area greater than the combined territories of Norway, Sweden and Denmark.26 Not only is the area of the ice cap covering the Arctic Ocean shrinking rapidly, but its thickness is also being affected by the climate changes. Since 1960, its average thickness has lessened by 10 to 15 percent; some regions show a 40-percent reduction.27 As for the snow coverage of the continental Arctic, that has diminished by 10 percent over the past 30 years.28 A study recently published by the World Wildlife Fund (WWF) apparently demonstrates an increase in the thaw season for sea ice and snow on the order of 13 days for the ice cap on the Arctic Ocean, four days for the Greenland ice cap and five days for northern Canada and Alaska.29

 Figure 1: Extent of sea ice, 1979                                       
       
               Source: NASA (2003)                                                                           

Figure 2: Extent of sea ice, 2003    

         Source: NASA (2003)

     
33. The authors of Arctic Council study, like those of the WWF study, point out that these changes are irreversible and that they are already threatening the survival of numerous animal species such as polar bears, sea elephants, seals and certain species of birds that depend on the sea ice or snow for their sustenance, reproduction or habitat. In the case of polar bears, the reduction in the extent of the sea ice combined with its delayed formation in the fall and the premature melting in the spring in Hudson Bay in Canada has already had significant effects. Between 1981 and 1998, there was a 15-percent reduction in the polar bears' weight and birthrate. The thinner the females are, the more likely their newborns are to be in poor health or to die prematurely.30

34. Although there is still a certain amount of scientific uncertainty about the ways to effectively measure precipitation in an environment as cold as the Arctic, precipitation also increased by eight percent during the 20th century. A disturbing fact is that most of this increase was in the form of rain, primarily during the winter and, to a lesser extent, the fall and spring. In some regions such as western Russia, liquid precipitation events increased by 50 percent in the past fifty years.31

35. The increase in temperatures in the Arctic also had effects on the region's various vegetation areas, which include, from north to south, the polar desert, the tundra and the boreal forest. Let us not forget that the wooded and forested stretches of the Arctic make up almost 30 percent of the planet's forests and that the boreal forest alone covers 17 percent of the land surface. As we will see further on, the most damaging and irreversible effects in this area will occur during the 21st century.

36. All these changes are quite obvious to the Aboriginal communities who live in the Arctic. In northern Canada, for example, the Inuit who have lived in that region for centuries maintain that the rise in temperatures threatens the environment that is the basis of their traditional way of life. Over the years they have noted a decrease in the number of polar bears, an increase in the number of summer storms, a significant thawing of the permafrost, which leads to erosion of the shores and significant damages to the road and economic infrastructures vital to the development of the Great North, the arrival of new animal and marine species from the south and, finally, the growing ineffectiveness, because of climatic instability, of traditional weather forecasting methods used when organizing hunting and fishing excursions. These observations are confirmed by the Aboriginal people living in Alaska, a region where the shores formed by the permafrost of the Barents Sea (southwest of the Arctic Ocean) suffered serious erosion because of the increase in the number of violent storms.32

V. THE INTENSIFICATION OF WARMING IN THE ARCTIC DURING THE 21ST CENTURY

37. Unfortunately, climatic forecasts for the 21st century are not optimistic, either for the planet as a whole or the Arctic. In 2001, the aforementioned IPCC report predicted, using six climatic forecast models, an average increase in world temperatures of 1.4 to 5.8°C by 2100. These increases are based on an increase of C02 concentrations in the atmosphere, for the same period, of 540 to 970 ppm.33 As well, the aforementioned increase in average temperatures would be, according to the various scenarios, two to ten times greater than those recorded during the 20th century and, based on the paleoclimatic data, without precedent in the last 10 000 years.34 The IPCC states that, despite a stabilization in C02 emissions during the 21st century, temperatures will continue to rise, because it will take many years for the atmospheric concentrations of this gas to diminish.

38. Still based on the six climatic forecast scenarios, the IPCC report predicts, with some regional variations, an increase in annual precipitation on the order of 5 to 20 percent. In the northern hemisphere, most of the increase will be in the summer and winter periods. Still based on the same models, sea levels-under the combined effect of melting ice and snow and the rise in both precipitation and water temperature-would increase by 9 to 88 centimetres, threatening the coastal populations in many countries such as Bangladesh and Senegal and U.S. states such as Florida and Louisiana.35

39. As with all the climate changes observed in the Arctic in the 20th century, those that will occur there by 2100 will be more severe than those observed on a planetary scale.

40. As well, using five forecast models that take into account different variables that could influence the region's climate, the authors of the study published by the Arctic Council predict that the average annual temperature will increase, between now and 2100, by 3 to 5°C close to the surface of the land and 4 to 7°C over the ocean. This increase will be more pronounced during the winter period, with respective increases of 4 to 7°C and 7 to 10°C. Regionally, temperatures will increase significantly in northern Russia and northern Canada.36 

41. This significant increase in temperatures will have numerous effects. First, precipitation, primarily in the form of rain, will increase by more than 20 percent by the end of the 21st century as a result of the increased evaporation of water from the melting of ice and snow. It will be concentrated in the coastal zones during the fall and winter. The increase in precipitation during these two seasons alone could reach almost 30 percent.37 

42. As for the sea ice, the five models used by the Arctic Council predict, still by 2100, an additional reduction in its extent on the order of 10 to 50 percent. This disturbing phenomenon will be accentuated during the summer, since the researchers' data predict a reduction of over 50 percent in the extent of the summer sea ice for the same period. Some models even predict the almost complete disappearance of the ice cap on the Arctic Ocean during the summer!38 As for Greenland, the data indicate that local temperatures will increase by 3°C during the 21st century, which will lead to the long-term and irreversible melting of the thick layer of ice covering the majority of this Danish territory. Since 1979, the area affected by melting ice has increased by 16 percent, an area roughly the size of Sweden. The study's authors state that, even if climatic conditions stabilize in the next century, the increase will have been enough to lead to the complete disappearance, over the next centuries, of Greenland's continental ice cap, which will in turn increase sea levels by more than seven metres.39

Figure 3:

Projected area of the sea ice in September during the 21e Century according
to the average of the five models

43. The same phenomenon will affect the snow cover of the continental Arctic, which could see its area reduced by 10 to 20 percent by 2100. As well, with the warmer temperatures, the snow will melt prematurely in the spring, thus increasing the flow of fresh water from rivers that empty into the Artic and North Atlantic oceans.40 

44. The composition of the Arctic vegetation could also be seriously changed, as we mentioned earlier. A study published by the WWF last January states that a 2°C increase in global temperature, which could happen between 2026 and 2060, would, by the end of the 21st century, lead to a 42-percent reduction in the tundra, an increase of more than 55 percent in the area of the boreal forest and the complete disappearance of the areas in which lichen currently grows.41 The limits of the boreal forest would then be pushed farther north. Although the study conducted for the Arctic Council states that a rapid increase in temperatures could compromise this scenario, since the transition period would be too quick, killing the trees and producing new ecosystems heretofore non-existent in the Arctic.42 For example, the boreal forest in Siberia could disappear in certain areas rather than migrating north. This would mean that the savannah would border directly on the tundra.  

45. What is more, the extent of the permafrost could be greatly reduced and compromise the northward movement of the boreal forest. This type of soil, which covers most of the continental Arctic, is composed primarily of earth, rocks or sediments whose temperature remains below 0°C for more than two consecutive years. There are two categories of permafrost. The first is continuous permafrost, that is, permafrost that occupies all of a given area and that can be 1500 metres deep. It is found primarily in Alaska, northern Canada-particularly the Northwest Territories and Nunavut-and Siberia. The second category is called sporadic or discontinuous permafrost. It occupies only 10 to 90 percent of a land surface in the Arctic and is no more than a few metres deep. 

46. Normally, the upper, or active, part of the permafrost thaws during the summer. In recent decades, however, scientists and Aboriginal communities have noticed that the temperature of this type of soil in the sub-arctic zones has increased by several degrees Celsius, to +2oC, thus increasing the depth of the thaw. In some regions, the active portion no longer freezes during the winter, which causes considerable damage to the Arctic's road and economic infrastructures.43 Over the course of the past 30 years, Alaska's Department of Natural resources has had to reduce, from 200 to 100 days, the period in which heavy equipment can be used for oil prospecting and development, because of the significant thawing of the permafrost.

47. In this regard, the warming temperatures will have two consequences during the 21st century. First, the permafrost degradation area will reach 10 to 20 percent of the total area in which this type of soil is found. Second, the southern boundary of the permafrost will recede by several hundred kilometres, particularly in Alaska, Canada and Russia.44 

48. Some argue that such a change will be beneficial in the long term because it will allow the boreal forest to move northward, for one thing, and will open up new farmland, for another. In order for these optimistic scenarios to become a reality, climate changes must occur in a linear and predictable fashion.

49. As with the vegetation, the authors of the Arctic Council study state that a rapid thawing of the permafrost could kill the trees and other forms of vegetation found there, as they would be literally drowned by the large quantities of water produced by the thawing soil. Once completely thawed, the water in the permafrost could simply drain off into the underground water networks, thus drying up the lakes and rivers on which the people, animals, fish and birds depend for their survival. Ultimately, this would lead to the partial desertification of some areas.45 As we said earlier, the thawing of the permafrost will also increase emissions of greenhouse gases since it contains methane from the decomposition of trees and tundra when it is thawed. Although present in lesser quantities, this greenhouse gas captures 23 times more heat in the atmosphere than CO2.

50. Thus, if these scenarios about the rising temperatures, melting of sea ice and snow, changes in vegetation and significant thawing of the permafrost materialize, the climatic warming will increase in the Arctic, which would create a sort of vicious circle whose dynamic will be difficult to break.  

51. In truth, all these factors explain why the Arctic is warming up faster than anywhere else on the planet. First, as the sea ice and snow melt, the soil and the ocean absorb more solar energy, since the process of albedo is greatly reduced; this combined with the effects of the thawing of the permafrost further increases temperatures in the Arctic. Second, the reduction in the area of the ocean covered by sea ice means that the solar energy absorbed by the ocean during the summer period is more easily transferable to the atmosphere, which explains in part why the temperatures is increasing more quickly in winter than in summer in this region of the planet. Finally, the changes in both the ocean and atmospheric currents observed in recent years also have an effect on the warming of this polar region.46       

VI. ABRUPT CLIMATE CHANGES: THE WEAKENING OF OCEAN CIRCULATION IN THE NORTH ATLANTIC REGION

52. At first glance, the warming of the Arctic, in addition to certain advantages we have already mentioned in terms of vegetation, could, provided the changes occur gradually, encourage the development of northern communities, particularly in northern Russia, Alaska and Canada, and in the areas of mineral and oil prospecting. The melting of sea ice could also open up new and highly lucrative sea-lanes. If this happens, some of the countries of the North Atlantic community such as Canada, the United States, Norway and Finland risk being confronted with new economic and geostrategic challenges. They will also be exposed to possible environmental catastrophes in an ecosystem already greatly weakened by climate changes.

53. That being said, at the beginning of this study we mentioned another disturbing problem likely to affect most of the countries of the Northern hemisphere. We mentioned that, beyond a certain, not easily identifiable threshold, global warming could produce abrupt climate changes such as a marked cooling of temperatures in certain regions of the globe. How could this happen and what role would the Arctic play in this phenomenon?

54. The Northern hemisphere, particularly the eastern portion of North America, Iceland and Europe, has a temperate climate and mild winters. Europe is particularly blessed in this regard. While the cities of London, Paris and even Moscow benefit from winters in which the temperatures are relatively mild and there are few snowstorms, cities situated at comparable latitudes in Canada must deal with winters in which daytime temperatures do not rise above - 15oC for days at a time and freezing rain and snowstorms follow one after the other, leaving tens of centimetres of snow and ice on the ground between November and March.
 
55. This situation results from the planetary ocean circulation that crosses the Atlantic, Antarctic, Indian and then Pacific oceans. What is sometimes called the conveyor belt of the oceans carries heat from the equatorial zones to the northern latitudes. Without this circulation, temperatures would be higher around the Equator and colder in the Northern hemisphere.

56. The surface water of the oceans benefits from a significant heat influx in the tropics that allows it to attain temperatures between 25 and 30oC, while in the polar regions, it scarcely rises above the freezing temperature of seawater, - 2oC. It thus forms a layer of warm water that can be tens of metres deep that is carried northward by the North Atlantic current better known as the Gulf Stream. Once it arrives on the coasts of Europe, Greenland and Iceland, the water temperatures cools again as the heat evaporates into the atmosphere. The heat is then taken up by winds coming from the west and carried over Europe. Once the heat escapes, the surface water possesses a high salinity rate, so as it cools, it sinks deep into the ocean mingling with the denser, colder water coming from the Arctic on the currents from Labrador, Denmark (Greenland) and the Faeroe Islands, west of Iceland. It then flows south, thus guaranteeing the constant influx of warm water into the northern latitudes.

57. This marine mechanism, illustrated by Figure 4, is in perpetual motion and thus plays a critical role in the regulation of the world's climate. Its functioning depends on a fragile balance between fresh and salt water. It is known as "thermohaline circulation," "thermo" for "heat" and "haline" for "water salinity," and it reduces the temperature differences between the equatorial regions and the polar zones.47 The Arctic plays an important role in this process, since the formation of sea ice maintains the salinity of the seawater and thus ensures the formation of denser water to feed the thermohaline circulation.48

58. According to the Ocean and Climate Change Institute (OCCI) affiliated with Woods Hole Oceanographic Institution in Maryland, U.S.A., the decisive influence of the North Atlantic current must not be overlooked because it carries twice as much heat as sea currents produced by winds would. The reviews of paleoclimatic data produced by that same institute indicate that the North Atlantic current is also the most unstable of the world's thermohaline circulation pathways.49

Figure 4:

Thermohaline circulation in the North Atlantic

        Source: United States National Oceanic and Atmospheric Administration (NOAA)

59. This historic instability is explained primarily by the influence of climatic warming in the Arctic, although more thorough research will be necessary in the coming years to confirm this theory. As we mentioned, the rising temperatures make the sea ice and snow melt much more quickly, thus producing an ever-increasing inflow of fresh water into the Arctic Ocean that then flows into the North Atlantic. Combined with the increase in precipitation predicted by the IPCC in 2001, the increase in the fresh water rate not only raises the sea level slightly, it also disrupts the fragile balance between the masses of fresh water and saltier water. In other words, the more fresh water there is in the North Atlantic, the higher the salinity level of the water at low latitudes will be, such that, once we cross a certain critical threshold that scientists are not currently able to determine, the surface waters will no longer be dense enough to sink to the ocean depths and perpetuate the thermohaline circulation. As a result of the increase in the level of fresh water, the thermohaline circulation could weaken or even stop completely for a period lasting several decades, indeed, over a century.50

60. The models used by the OCCI make clear that a marked weakening or total interruption of the North Atlantic current would cause a drop in temperature in the Northern hemisphere of 3 to 5oC, which is a least a third of the climatic cooling during the major ice ages that the Earth has experienced over the millennia.

61. These climate changes are far from insignificant. According to the OCCI, they are twice as great as those observed during the worst winters in eastern North America. It is important to point out, however, that a drop in temperatures in the Northern hemisphere will not affect the entire planet. In fact, climatologists say that changes that occur at high latitudes are less likely to influence the global climate than those that occur at lower latitudes, such as those caused by El Nin?o.51

62. The paleoclimatic data used not only by the OCCI, but also by the scientists at the National Oceanographic and Atmospheric Administration of United States (NOAA) and by those who produced the aforementioned study for the National Academy for Science on abrupt climate changes, tend to show that, 12 700 years ago, a major weakening of the North Atlantic current apparently caused an abrupt and marked drop in temperatures in the Northern hemisphere, for a period of 1300 years. This phenomenon apparently occurred following a significant rise in temperatures at the end of the last great ice age, 14 500 years ago. After a rapid climatic warming of more than 10oC, temperatures dropped abruptly, over the space of a few decades, by more than 5oC in Greenland. This colder period accompanied by a dry climate is known as the Younger Dryas event, named after a flower that grew in Europe at the time. This cooling event occurred during a period when the influx of fresh water into the North Atlantic Ocean was very high. At the time, it was not uncommon to find glaciers close to the coasts of Portugal. This period ended abruptly, 11 400 years ago, with a temperature increase, still in Greenland, of 10oC in a single decade!52

63. A less severe cooling event occurred in the Northern hemisphere 8200 years ago, after a period of climatic warming similar to the one we are currently experiencing. This episode, in which the temperature of Greenland fell by 5oC, was also apparently caused by a significant weakening of the North Atlantic current.53 More recently the paleoclimatic data suggest that the Little Ice Age that hit Europe hard from 1300 to 1850 was apparently caused by a weakening of the North Atlantic current, volcanic eruptions and a temporary drop in solar energy. During this period, the temperature in the western portion of the Northern hemisphere dropped by 1oC, producing a drop in precipitation that seriously affected Europe's agriculture and economy. The scarcity of food and other resources also caused numerous political-military problems, great famines-particularly in the Viking countries between 1315 and 1319 and in Ireland, where a million people died-and devastating plagues.

64. In its 2001 report, the IPCC states that, despite the records of warmer temperatures during the Middle Ages, the paleoclimatic data show that, from the 11th century to the middle of the 19th century, at the beginning of the Industrial Revolution, there was a strong downward trend in temperatures in the Northern hemisphere, a trend that changed direction abruptly as the data we have cited demonstrates.54

65. That being said, could the North Atlantic current again weaken over the coming decades to the point where an event such as the Little Ice Age or, worse, the Younger Dryas recur and thus threaten the economic, political and geostrategic stability of the Northern hemisphere, and Europe in particular? During recent years, the magazine Nature has published a series of scientific studies based on recent observations and paleoclimatic data that confirm a certain weakening of the current over the past 40 years, particularly since the early 1990s.55 These studies state that the salinity rate of the water in the North Atlantic, and particularly the water from the deep currents of Labrador, Denmark and the Faeroe Islands, has diminished slightly while further south, near the Equator, it has increased slightly, thus threatening the balance on which the thermohaline circulation in this region depends. Moreover, a number of these studies, like the one done for the Arctic Council, note that the western part of the North Atlantic has cooled down in recent years while the Artic has warmed up greatly.

66. On June 16, 2005, the magazine Science published an original study funded by the Woods Hole Oceanographic Institution and the Norwegian Research Council, confirming the aforementioned findings. 56 For the first time in the history of science, experts have estimated that an additional 19,000 km3 of freshwater flowed from the Arctic to the North Atlantic between 1960 and 1995, via deep currents located to the west and the east of Greenland.  In a normal year, 5000 km3 of freshwater flows through these deep ocean currents.  The study indicates that close to half of this additional flow occurred in the late 1960s, increasing the normal flow by over 40% to 7000 km3.57  Although there is some scientific uncertainty to be resolved in future research, the study's authors nevertheless assert that this worrisome process will likely continue. They also mentioned that, beyond a critical threshold that is difficult to identify and could be reached in the 21st century, this could disturb ocean circulation in the North Atlantic before 2200.

67. While the authors of all these studies do not have sufficient data to determine whether this is a temporary phenomenon or a general trend heralding major long-term climate changes for Europe and North America similar to those that occurred in the past, they do agree that it may be one of the consequences of global warming and the melting of sea ice and snow and of increased precipitation in the Arctic.

68. In 2001, the IPCC mentioned in its report that the climatic warming simulation models for the 21st century suggest a weakening of the North Atlantic current. Beyond the year 2100, however, these same models predict that this current could be interrupted completely, and irreversibly, if the warming continues at an accelerated rate throughout the 21st century.58 

69. The authors of the study conducted for the American Department of Defence on the consequences of an interruption in the thermohaline circulation in the North Atlantic based their scenario on a cooling event that occurred 8200 years ago. They simulated a marked weakening of the current between 2010 and 2020. According to their scenario, such an event would produce a temperature drop in the Northern hemisphere of almost 5oC, a 30-percent reduction in precipitation and a 15-percent increase in wind strength during that decade.

70. The authors readily acknowledge that their scenario is not based on any specific scientific study predicting such an event in the next 15 years and that, on the contrary, this scenario would more likely occur over many decades or centuries. Their study does nevertheless simulate the human, economic, political and geostrategic effects such a cooling, and more specifically the reduced precipitation, would have for the North Atlantic community.

71. Some will say that this event will never happen or that the many uncertainties in the results of the paleoclimatological and scientific studies cited in this report should incite political decision-makers to be very cautious and focus their efforts on measures to reduce greenhouse gas emissions.  We maintain that we have shown judgement and intellectual honesty in rigorously describing a phenomenon that at present is merely a theoretical threat. The data presented in this study show that there is a chance it might happen again and that the repercussions could be more severe than in the past given the level of economic and technological advancement of societies living in the Northern hemisphere.  As Richard B. Alley, head of the National Academy for Science research committee looking into this matter noted, "The model used to project future climate changes and their impacts are not especially good at stimulating the size, speed, and extent of the past changes, casting uncertainties on assessments of potential future changes. Thus, it is likely that climate surprises await us."[Translation]60  This is not being alarmist but rather reflects an interest in preventing the chaos that could be wrought by sudden and significant climate change such as the human race has never witnessed.

VII. CONCLUSION: THE NEED FOR A BETTER UNDERSTANDING OF CHALLENGES TO NATO SECURITY INITIATED BY ABRUPT CLIMATE CHANGES

72. Needless to say, "securitizing" an issue can provide it with a status otherwise not granted.  The term security can well become a political tool in the competition for government attention.  Thus, what gets onto the agenda may well reflect the interests of some over those of others.  If global warming and abrupt climate changes are truly "common security" interests, then while continuing to strongly encourage efforts to reduce greenhouse gas emissions, we must also be careful not to ignore these interests because their effects are largely asymmetrical; in other words, they are more of a problem for the developing world than for other countries.  Getting the issue on the agenda needs to be a priority .

73. To a certain extent, your Rapporteur believes NATO has already taken the initial step.  Its Committee on the Challenges of Modern Society was created in 1969 with the aim of addressing problems affecting the environment of member nations and the quality of life of their people.  Today, the Committee also meets with partner countries.  The key objectives guiding the work of the Committee include:

* Reducing the environmental impact of military activities;
* Conducting regional studies including cross-border activities;
* Preventing conflict in relation to the scarcity of resources;
* Addressing emerging risks to the environment and society that could cause economic, cultural and political instability; and
* Addressing non-traditional threats to security.

74. The Committee itself does not engage in research activities.  Rather, work is carried out on a decentralized basis, mainly through pilot studies of three to five years and short-term ad hoc projects from 12 to 18 months, which are nationally funded.  Activities also include the organization of topical workshops and the co-sponsoring of international conferences and seminars.  Although the work of the Committee is limited, it is at least evidence of the fact that environmental factors such as abrupt climates changes in strategic analysis are regarded as increasingly important.

75. Your Rapporteur is of the opinion that, as an assembly, we are well suited to take stock of these new security concerns-for they have political, military, economic, scientific and social implications.  Our various committees may well wish to devote some effort to examining these implications from their particular perspective, thereby enabling us collectively to make a useful contribution.
76. In this regard, in an aforementioned study, the National Academy for Science issued a series of recommendations that the assembly could draw on to guide its research.  The Rapporteur wishes to emphasize that a number of these recommendations were repeated by the Woods Hole Oceanographic Institution in a brochure distributed to the world's leading political and economic decision-makers at the Davos World Economic Forum, in January 2003.61  In particular it recommends:

* Creating research programs to gather data on the non-linear evolution of ecosystems.  This includes the workings of ocean and atmospheric currents, of sea ice and of hydrological networks, which as we have noted can all lead to sudden climate change;

* Increasing the quantity of paleoclimatological data and maximizing their use in order to better understand the reasons for these phenomena and their harmful effects.  Such work could be multidisciplinary;

* Developing long-term forecasting models relating to environmental change and its effects on the economy and society that include sudden climate change and not only gradual and linear changes; and

* Implementing preventive policies to reduce the effects of extreme and irreversible weather changes on the environment and society.  In other words, stabilize and than reduce greenhouse gas emissions, reduce damage to biodiversity and strengthen public and private institutions to withstand such a situation.  In order to attain these objectives, developed countries will have to assist poorer countries so this exercise is not limited to a few regions of the planet.

77. The authors of the report published by the American Department of Defence repeat most of the aforementioned recommendations.  They also proposed other avenues to consider that, although intended primarily for the United States, could also apply to other countries.  They recommended:

* That the American government develop variables to measure the country's vulnerability to sudden climate change in the following areas: agriculture, drinking water, social cohesion, natural resources and technologies; 

* That this exercise be conducted for each region of the country; and

* That rapid response teams be created if this phenomenon occurs in order to better control population migration, pandemics and the distribution of food and water.
 
78. These recommendations show that our knowledge of these matters needs to be increased quickly. That being said, the urgency of the proposed studies is, in your Rapporteur's opinion, highlighted by the results of simulations presented in the document commissioned by the United States Department of Defence.  While the scenario presented is extreme, it challenges our "[...] security in ways that should be considered immediately."62 It concludes that global warming "[...] should be elevated beyond a scientific debate to a U.S. national security concern."63  If such an eventuality should ever become a security concern for the United States, it would, most certainly, also become one for many of the rest of us. Unless we are properly prepared to respond to extreme climatic events, the Earth might be much less able to support human life.   
79. The report goes on to explore how such abrupt climate change could de-stabilize the geo-political environment leading to various types and levels of conflict due to resource constraints.  The latter would include, inter alia, food shortages, the decreased availability of fresh water and disruptions in energy supplies.  As global and local carrying capacities decrease, those with adequate resources, such as the United States, Canada and most of European countries, could well turn themselves into fortresses while the less fortunate could engage in offensive forays into neighbouring countries or regimes.

80. For example, the paper says that in North America, the need for better security could mean, by 2020, that the United States forms an integrated security alliance with Canada and Mexico in order to stop the flow of refugees coming from Caribbean Islands that were flooded and Europe. Finally, shortage of oil combined with decreasing temperatures in the Northern Hemisphere could trigger a military conflict in the Persian Gulf between China, India, Europe, and the United States.   

81. It is the strong belief of your Rapporteur that the likelihood of internecine conflict would increase; now being fuelled not only by old enmities but also resource scarcities.  Differing alliances could be formed as priorities shift and the goal is resources for survival rather than ideology, religion, or more traditional forms of nationalism.  New challenges will then require new approaches and mechanisms. They will need to be defined over the following years by this Assembly.

____________________
1  See Ibrügger, Lothar. From Kyoto to Buenos Aires: The Agreement on Greenhouse Gas Emissions. Brussels. Committee on Science and Technology - NATO Parliamentary Assembly. 1998.
2  Collaboration. Abrupt Climate Change: Inevitable Surprises - Report in Brief. Washington. National Academy Press. 2002. p. 1.
3  Collaboration, Climate Change 2001: IPCC Third Assessment Report. Cambridge University Press, Cambridge, 2001, 398 p.
4  The IPCC consists of three working groups. At present, the groups have the following responsibilities: Group I must study the scientific aspects of the climate system and its evolution; Group II looks at the effects of climate changes and ways to adapt to these changes; and Group III examines various possible ways to mitigate climate changes. The IPCC produced its first assessment report in 1990 and its second in 1996.
5  Collaboration. Climate Change 2001: Synthesis Report - Summary for Policymakers. 2001. pp. 14-15.
6  Collaboration. Abrupt Climate Change: Inevitable Surprises. Washington. National Academy Press. 2002, 244 p.
7  Paleoclimatology analyses historical data such as that from ice core samples taken in polar regions, primarily in order to better understand the effects of human activities on climatic processes. The best examples of climate variations are illustrated by the periods of glaciation and warming. The mechanisms underlying such changes include sea currents and continental drift related to plate tectonics, but also include the cyclical variations in the Earth's annual orbit around the Sun and the inclination of its axis in relation to the plane of that elliptical orbit.
8  Randal, Doug and Shwartz. An Abrupt Change Scenario and Its Implications for United States National Security. Washington. United States Department of Defence, 2003. 22 p.
9  Collaboration. Climate Change 2001: The Scientific Basis - Report of Working Group 1 (IPCC). Cambridge.  Cambridge University Press. 2001. p. 26
10  Ibid, p. 26 (Supra, Note 9)
11  Ibid, p. 6 (Supra, Note 9) 
12  International Climate Change Task Force. Meeting the Climate Challenge. London. Institute for Public Policy Research. 2005. p.4
13  Ibid, p. 6 (Supra, Note 9)
14  Ibid, p. 6 (Supra, Note 9)
15  Ibid, p. 6 (Supra, Note 5)
16  Ibid, p. 6 (Supra, Note 5)
17  Ibid, p. 6 (Supra, Note 5)
18  Ibid, p. 28 (Supra, Note 9)
19  Ibid, p. 29 (Supra, Note 9)
20  Ibid, p. 29 (Supra, Note 9)
21  Collaboration. Climate Change 2001: Impacts, Adaptation and Vulnerability - Report of Working Group II (IPCC). Cambridge. Cambridge University Press. 2001. p. 65. 
22  New, Mark. "Arctic Climate Change with a 2oC Global Warming." p. 8. In L. Rosentrater. 2o is too much: Evidences and Implications of Dangerous Climate Changes in the Artic. Norway. LDR Consulting for World Wildlife Fund. 2005. 70 p.
23  The, member countries of the Arctic Council are Canada, the United States (Alaska), Denmark (Greenland and Faeroe Islands), Iceland, Norway, Sweden, Finland and Russia, as well as the Aboriginal communities living in these countries.
24  Collaboration. Impacts of a Warming , Arctic: Arctic Climate Impact Assessment. Cambridge. Cambridge University Press. 2004. 144 p.
25  Collaboration, Impacts of a Warming Arctic: Arctic Climate Impact Assessment - Supporting Evidence for the Key Findings. Cambridge. Cambridge University Press. 2004. p. 23.
26  Ibid, p. 25 (Supra, Note 24)
27  Ibid, p. 25 (Supra, Note 24)
28  Ibid., p. 31 (Supra, Note 24)
29  Comiso, Josefino O. "Impact Studies of a 2oC Global Warming on the Arctic Sea Ice Cover." p. 50. In L. Rosentrater. 2o is too much: Evidences and Implications of Dangerous Climate Changes in the Artic. Norway. LDR Consulting for World Wildlife Fund. 2005. 70 p.
30  Ibid, p. 58 (Supra, Note 24)
31  Ibid, p. 22 (Supra, Note 24)
32  Ibid, pp. 78-81 (Supra Note 24); Crowler, Paul, T. Fenge and S. Watt-Cloutier. "Responding to Global Climate Change: The Perspective of the Inuit Circumpolar Conference on the Arctic Climate Impact Assessment." pp. 58-60. In L. Rosentrater. 2o is too much: Evidences and Implications of Dangerous Climate Changes in the Artic. Norway. LDR Consulting for World Wildlife Fund. 2005. 70 p.
33  Ibid, p. 8 (Supra Note 5)
34  Ibid, p.8 (Supra Note 5)
35  Ibid, p. 9 (Supra Note 5)
36  Ibid, pp. 26-27 (Supra Note 24)
37  Ibid, p. 29 (Supra Note 24)
38  Ibid, p. 30 (Supra Note 24)
39  Ibid, p. 33 (Supra Note 24)
40  Ibid, p. 31 (Supra Note 24)
41  Kaplan, Jed O. "Climate Change and Arctic Vegetation." p. 25. In L. Rosentrater. 2o is too much: Evidences and Implications of Dangerous Climate Changes in the Artic. Norway. LDR Consulting for World Wildlife Fund. 2005. 70 p.
42  Ibid, p. 52 (Supra Note 24)
43  Ibid, p. 87 (Supra Note 24)
44  Ibid, p. 87 (Supra Note 24)
45  Ibid, pp. 91-92 (Supra Note 24)
46  Collaboration. Impacts of a Warming Arctic: Arctic Climate Impact Assessment-Summary. Cambridge. Cambridge University Press. 2004. p. 20.
47  Ibid, pp. 35-36 (Supra Note 24); Joyce, Terrance and Lloyd Keigen, Abrupt Climate Change: Are we on the Brink of a New Little Ice Age? Woods Hole. Woods Hole Oceanographic Institution (Ocean and Climate Change Institute), 7 p.
48  Ibid, p. 36 (Supra Note 24)
49  Ibid, p. 4. (Supra Note 46)
50  Ibid, p.4 (Supra Note 46), Ibid, p. 2 (Supra Note 2), Ibid, pp. 8-10 (Supra Note 9)
51  Ibid, p. 4 (Supra Note 46)
52  Collaboration. Mechanisms that Can Cause Abrupt Climate Change. National Atmospheric and Oceanographic Administration. United States Government, 3 p.
53  Ibid, p. 6 (Supra Note 9), Ibid, (Supra Note 2)
54  Ibid, (Supra Note 20)
55  See Hansen, Bogl, S. Osterhus and W.H. Turrell. "Decreasing overflow from the Nordic seas into the Atlantic Ocean through the Faroe channel since 1950." Nature. Vol. 411. 21 June 2001. pp. 927-930; Dickson Bob, Stephen D., J. Holfort, J. Meincke, W.R. Turrell and I. Yashayaev. "Rapid Freshening of the deep North Atlantic Ocean over the past four decades." Nature. Vol. 416. 25 April 2002. pp. 832-837; Curry, Ruth, B. Dickson and I. Yashayaev. "A change in freshwater balance of the Atlantic Ocean over the past four decades." Nature. Vol. 426. 18-25 December 2003. pp. 826-829; Häkkinen and P.B. Rhines. "Decline of Subpolar North Atlantic Circulation During the 1990s." Science Magazine. Vol. 304. 23 April 2004. pp. 555-559.
56 Curry, R. and C. Mauritzen.  "Dilution of the Northern North Atlantic Ocean in Recent Decades." Science, Vol. 308, No. 5279. June 2005, pp. 1772-1774.
57 By comparison, the flow rate of the Mississippi River in the United States is 500 km3 per year and that of the Amazon River, the largest river in the world, is 5000 to 6000 km3.
58  Ibid, p. 15  (Supra Note 5)
59 Collaboration. Abrupt Climate Change: Inevitable Surprises - Executive Summary. Washington. National Academy Press. 2002. p. 5 (Preface).
60 Collaboration. Abrupt Climate Change: Inevitable Surprises - Executive Summary. Washington. National Academy Press. 2002. p. 5 (Preface).
61 Collaboration.  Abrupt Climate Change: Inevitable Surprises ? Executive Summary.  Washington, National Academy Press, 2002, pp. 1-9.
62  Ibid, p. 1 (Supra Note 8)
63  Ibid, p. 3 (Supra Note 8)