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CHAPTER ONE 1.0 INTRODUCTION The Ocean is of great importance to man and its environment. The ocean which is a large body of inter-connected waters has been helping to control global climate change by reducing the amount of injurious gases such as CO2 and others in the atmosphere. Despite its enormous importance in regulating global climate and its sensitivity to the impacts of climate change and ocean acidification, the ocean continues to get only peripheral attention in global climate research, climate change policy and implementation plans. Due to civilization and industrialization, anthropogenic activities now pose a great threat to humans in return and the marine body organisms. Increased carbon dioxide (CO2) from the burning of fossil fuels and other human activities continues to affect our atmosphere, resulting in global warming and climate change. Less well known is that this carbon dioxide is altering the chemistry of the surface oceans and causing them to become more acidic. Increased carbon dioxide (CO2) from the burning of fossil fuels and other human activities continues to affect our atmosphere, resulting in global warming and climate change. This REPORT provides an overview of the interactions between the ocean and climate and describes the impacts of climate change on the ocean and particularly the marine ecosystem. CHAPTER TWO 2.0 THE OCEAN From the ancient Greek word “Okeanos” meaning, the sea of classical antiquity is a body of salt water that composed much of the planet hydrosphere. On earth, an ocean is one of the major convectional division of the world ocean which covers almost 71% of the surface of the earth. These are in descending order by area, the Pacific, Atlantic, Indian, Southern and Arctic oceans. The word Sea is used interchangeably with ocean in American English but, strictly speaking, a sea is a body of saline water (generally a division of the world ocean) partly or fully enclosed by land. Saline water covers approximately 71% of the planet’s surface and is customarily divided into several principal ocean and sea. The ocean contains 97% of the earth’s water and oceanographers have said that less than 5% of the world ocean has been explored. The total volume is approximately 1.35 billion cubic kilometers, with an average depth of nearly 3700m (3.7km). As it is the principal component of earth hydrosphere, World Ocean is integral to all known life. It forms part of the carbon cycle, and influences climate and weather patterns. It is the habitat of 230,000 known species, although much of the ocean’s depth remains unexplored and over 2,000,000 marine species are estimated to exist. The origin of earth’s ocean remains unknown; oceans are thought to have formed in the Hadean period and may have been the impetus for the emergence of life. Extraterrestrial oceans may be composed of water or other elements and compounds. The only confirmed large stable of bodies of extraterrestrial surface liquid is the Lake of Titan, although there is evidence for the existence of oceans elsewhere in the solar system. Early in their geologic histories, Mars and Venus are theorized to have had large water oceans. The Mars ocean hypothesis suggests that nearly a third of the surface of the Mars was once covered by water, and a runaway greenhouse effect may have boiled away the global ocean of the Venus. Compounds such as salt and ammonia dissolved in water lower its freezing point so that water might exist in large quantities in extraterrestrial environments as brine or convecting ice. Unconfirmed oceans are speculated to exits beneath the surface of many dwarf planets and natural satellites, notably the ocean of Europa is estimated to have over twice the water volume of Earth. The solar system’s giant planets are also thought to have liquid atmospheric layers of yet to be confirmed composition. Ocean may also exist on exoplanets and exomoons, including surface oceans of liquid water within a circumstellar habitable zone. Ocean planets are a hypothetical type of planet with a surface completely covered with liquid. Though generally described as several separate oceans, these waters comprise one global, interconnected body of salt water sometimes referred to as the world ocean or global ocean. This concepts of a continuous body of water with relatively free interchange among its parts is of fundamental importance to oceanography. 2.1 CLIMATE Climate of an area is the average weather condition of a place over a very long period of time. It can be understood most easily in terms of annual or seasonal averages of temperature and precipitation. Land and sea areas, being so variable, react in many different ways to the atmosphere, which is constantly circulating in a state of dynamic activity. Day-by-day variations in a given area constitute the weather, whereas climate is the long-term synthesis of such variations. Weather is measured by thermometers, rain gauges, barometers, and other instruments, but the study of climate relies on statistics. Today, such statistics are handled efficiently by computers. A simple, long-term summary of weather changes, however, is still not a true picture of climate. To obtain this requires the analysis of daily, monthly, and yearly patterns. Investigation of climate changes over geologic time is the province of paleoclimatology, which requires the tools and methods of geological research. The word climate comes from the Greek klima, referring to the inclination of the sun. Besides the effects of solar radiation and its variations, however, climate is also influenced by the complex structure and composition of the atmosphere and by the ways in which it and the ocean transport heat. Thus, for any given area on earth, not only the latitude (the sun's inclination) must be considered but also the elevation, terrain, distance from the ocean, relative to mountain systems and lakes, and other such influences. Another consideration is scale: A macroclimate refers to a broad region, a mesoclimate to a small district, and a microclimate to a minute area. A microclimate, for example, can be specified that is good for growing plants underneath large shade trees. Climate has profound effects on vegetation and animal life, including humans. It plays statistically significant roles in many physiological processes, from conception and growth to health and disease. Humans, in turn, can affect climate through the alteration of the earth's surface and the introduction of pollutants and chemicals such as carbon dioxide into the atmosphere. 2.1.1 CLIMATE CHANGE According to the United Nations’ Intergovernmental Panel on Climate Change (IPCC, 2007), climate change is “a change in the state of the climate that can be identified (e.g., using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer. It refers to any change in climate over time, whether due to natural variability or as a result of human activity’’. Global Warming or Climate Change leaves measurable increase in the average temperature of Earth’s atmosphere, oceans, and landmasses. Scientists believe Earth is currently facing a period of rapid warming brought on by rising levels of heat-trapping gases, known as greenhouse gases, in the atmosphere. Greenhouse gases retain the radiant energy (heat) provided to Earth by the Sun in a process known as the greenhouse effect. Greenhouse gases occur naturally, and without them, the planet would be too cold to sustain life as we know it. However, since the beginning of the Industrial Revolution in the mid-1700s, human activities have added more and more of these gases into the atmosphere. For example, levels of carbon dioxide, a powerful greenhouse gas, have risen by 35 percent since 1750, largely from the burning of fossil fuels such as coal, oil, and natural gas. With more greenhouse gases in the mix, the atmosphere acts like a thickening blanket and traps more heat. Climate change is caused by the release of greenhouse gases (GHGs) into our atmosphere -primarily caused by the burning of fossil fuels. Fossil fuels, such as petroleum and coal, release carbon dioxide that traps heat in our atmosphere. Global temperatures have already increased by 1.4°F since the Industrial Revolution, with much of this warming occurring in just the last 30 years alone. ‘The earth’s climate is influenced by many factors, including solar radiation, wind, and ocean currents’. Figure 1: The climate system, sub-system, relevant processes and interactions Climate changes can be triggered in two different ways – by internal and external forces. The internal forces include: • Changes in a single climate component, for example, an anomalous ocean current; • Changes in the interactions between different climate components, for example, between the ocean and atmosphere. Compared to these, the external mechanisms at first glance appear to have nothing to do with the climate system. These include: • The very slow drift of continents, which moves land masses into different climate zones over millions of years; • The changing intensity of radiation emitted by the sun. The radiation energy of the sun fluctuates over time and changes temperatures on Earth; • Volcanic eruptions, which inject ash and sulphur compounds into the atmosphere, influence the Earth’s radiation budget and thus affect climate. 2.1.2 HOW HUMANS CHANGES THE CLIMATE The human impact on climate has greatly increased over the past hundred years. We release vast amounts of climate- relevant trace gases into the atmosphere. This changes the radiation balance of the atmosphere and leads to global warming. In addition to carbon dioxide, these trace gases include methane, nitrous oxide (laughing gas), halogenated fluorocarbons, perfluorinated hydrocarbons, and sulphur hexafluoride. But carbon dioxide (CO2) is especially important for the Earth’s climate system because the worldwide output is so enormous. It is released primarily through the burning of fossil fuels (oil, natural gas, and coal) in power plants, vehicle engines or in household heating systems. Its atmospheric levels have risen to almost390 parts per million (ppm) today as compared to the preindustrial value of 280ppm. With this increase, the temperature has also risen during the twentieth century. The internally driven changes in the oceans such as changes in the Gulf Stream also occur within a time frame of decades or a few centuries. These have a decisive influence on climate and on the concentration of greenhouse gases in the atmosphere because they are strongly involved in global mass cycles such as the carbon cycle. For example, CO2 dissolves easily in water. However, the oceans have taken up about half of all the carbon dioxide produced by the burning of fossil fuels since the beginning of the industrial revolution, which has clearly dominated the natural variations. Whether the climate will change in the future, and by how much, can therefore be also deduced from the oceans. Climate will change very slowly in the future because the oceans with their immense volumes of water react very gradually to change. Therefore, many but not all of the consequences of climate change triggered by human activity will only gradually become noticeable. Some of these consequences could actually be irreversible when certain thresholds are crossed. At some point it will no longer be possible, for instance, to stop the complete melting of the Greenland ice sheet and the resulting seven- meter rise of sea level. The position of the threshold, however, is not precisely known. But one thing is certain: Even if the emission of carbon dioxide were stabilized at today’s levels it would not lead to a stabilization of the carbon dioxide concentration in the atmosphere, because carbon dioxide is extremely long-lived and the carbon dioxide sinks, mainly the oceans, do not absorb it as quickly as we produce it. The situation is different for short-lived trace gases like methane (CH4). If methane emissions were stabilized at the present level, the methane concentration in the atmosphere would also stabilize, because methane diminishes in the atmosphere at about the same rate as it is emitted. In order to maintain the carbon dioxide concentration at a given level, the emissions have to be reduced to a fraction of the present amounts. 2.1.3 PEOPLE, THE OCEAN AND CLIMATE CHANGE People, the ocean and the climate are inextricably linked: the circulation patterns of ocean currents make our planet inhabitable; about half of the oxygen in the atmosphere is derived from oceanic sources; and large sectors of the global economy depend on ocean-related commerce, including fisheries, tourism and shipping. People all over the world rely on the ocean for their basic caloric needs, and some coastal peoples obtain 100% of their animal protein from its waters. Regardless of where we reside, however, we depend on healthy ocean ecosystems and the services that they provide. The ocean is the life support system for our planet. The ocean covers more than 70% of the planet’s surface and is so immensely deep that it contains over 90% of the inhabitable space for life on Earth. All parts of this space are filled with magnificent biodiversity, ranging from relatively simple, but extraordinarily abundant microbes to some of the most social and intelligent animals on Earth: whales. In fact, approximately 90% of the planet’s biomass lives in the ocean. Now, the ocean is facing new and substantial threats, as a result of climate change, which compound existing pressures from growing human activity in the ocean. The scale and rate of environmental change, driven by increases in concentration of greenhouse gases in the atmosphere, is unprecedented in human history. These changes will negatively affect the ocean’s ability to continue to support ecosystems, human populations, and cultures. The ocean and the atmosphere are so completely intertwined that negotiations surrounding future climate change mitigation and adaptation actions cannot be complete without consideration of both. The coupling of these two global systems not only regulates the earth’s climate but also provides all species, including humans, a favorable environment, in which to grow and reproduce. The ocean plays an integral part in influencing our climate and is intrinsically linked to the atmosphere through: Heat storage Transportation of heat around the globe Evaporation freezing and thawing in polar regions Gas storage and exchange especially CO2 2.2 GREENHOUSE EFFECT Primarily, the average temperature of the earth is believed to be 15°c when we have the atmosphere and -18°c when there is no atmosphere. This can be explained through the reactive effect of the atmosphere to the long-wave radiation coming from the earth. Radiation from the sun passes through the atmosphere like a transparent medium to the earth as short-wave radiation. Immediately it reaches the earth surface, it is reflected back into the atmosphere which contains some gases known as the greenhouse gases which are capable of absorbing this radiation. Examples are carbon dioxide (CO₂), water vapour (H₂O),methane(CH₄), ozone (O₃), chlorofluorocarbons (CFCs). Immediately the radiation reaches the atmosphere and is absorbed by the greenhouse gases, it is reflected back unto the earth surface. It is either absorbed and transmitted or scattered. This in turn heats the earth surface and warms the globe. Figure 2: Surface temperature with the atmosphere Figure 3: Surface temperature without the atmosphere The warming of the globe known as global warming therefore exchanges of exchanges its heat with other reservoirs such as the ocean. The ocean is affected in so many ways and these include ocean acidification, ocean warming, ocean pollution and so on. Apart from the natural causes of the global warming, there are anthropogenic processes such as gas flaring, burning of fossil fuels, fumes from cars, industrial waste which when released into the atmosphere have negative effects on the climate which in turn impact the ocean negatively. Figure 4: Increase in CO2 with sea level rise Even if it is possible to significantly reduce the emission of greenhouse gases, andCO2 in particular, by the end of this century, the impact will still be extensive. CO2 has a long life and remains in the atmosphere for many centuries. Because of this, the temperature on the Earth will continue to rise by a few tenths of a degree for a century or longer. Because heat penetrates very slowly into the ocean depths, the water also expands slowly and sea level will continue to rise gradually over a long period of time. Melting of the large continental ice sheets in the Antarctic and Greenland is also a very gradual process. Melt water from these will flow into the ocean for centuries or even millennia, causing sea level to continue to rise. The figure illustrates the principle of stabilization at arbitrary levels of CO2 between 450 and 1000 parts per million (ppm), and therefore does not show any units on the response axis. Covering about 70 percent of the Earth’s surface, the world’s oceans have a two-way relationship with weather and climate. The oceans influence the weather on local to global scales, while changes in climate can fundamentally alter many properties of the oceans. This presentation topic examines how some of these important characteristics of the oceans have changed over time. 2.2.1 WHY IT MATTERS As greenhouse gases trap more energy from the sun, the oceans are absorbing more heat, resulting in an increase in sea surface temperatures and rising sea level. Changes in ocean temperatures and currents brought about by climate change will lead to alterations in climate patterns around the world. For example, warmer waters may promote the development of stronger storms in the tropics, which can cause property damage and loss of life. The impacts associated with sea level rise and stronger storms are especially relevant to coastal communities. Although the oceans help reduce climate change by storing large amounts of carbon dioxide, increasing levels of dissolved carbon are changing the chemistry of seawater and making it more acidic. Increased ocean acidity makes it more difficult for certain organisms, such as corals and shellfish, to build their skeletons and shells. These effects, in turn, could substantially alter the biodiversity and productivity of ocean ecosystems. Changes in ocean systems generally occur over much longer time periods than in the atmosphere, where storms can form and dissipate in a single day. Interactions between the oceans and atmosphere occur slowly over many months to years, and so does the movement of water within the oceans, including the mixing of deep and shallow waters. Thus, trends can persist for decades, centuries, or longer. For this reason, even if greenhouse gas emissions were stabilized tomorrow, it would take many more years —decades to centuries—for the oceans to adjust to changes in the atmosphere and the climate that have already occurred. CHAPTER THREE 3.0 IMPACT OF CLIMATE CHANGE ON THE OCEAN As a result of the change in climate over time, the effects are more felt in the ocean which in turn affects humanity and their daily activities. These include 3.0.1 OCEAN ACIDIFICATION Ocean acidification, which affects the carbonate chemistry of the ocean, is directly caused by greater atmospheric emissions of CO2. These emissions have increased over the last 200 years, primarily due to intensified industrialization and agriculture resulting in greater burning of fossil fuels, cement manufacturing and land use change. The ocean has become more acidic over the past few centuries because of increased levels of atmospheric carbon dioxide, which dissolves in the water. Higher acidity affects the balance of minerals in the water, which can make it more difficult for certain marine animals to build their skeletons and shells. About a third of the carbon dioxide (CO2) emitted to the atmosphere through human activities is being absorbed by the ocean causing a change in the ocean’s chemistry. This is known as Ocean Acidification. Greater levels of dissolved CO2 lead to seawater that is more corrosive or acidic and impacts to marine life are already being observed along the West Coast. Increased acidity can limit the ability of organisms, such as oysters and particularly vulnerable early life stages, to form shells and skeletons that are made up of calcium carbonate. Adding to the complexity, ocean acidification is not an isolated threat, but part of a shifting environment in which carbonate chemistry and dissolved oxygen are changing alongside nutrients and temperature. While the extent of impacts is still uncertain, ocean acidification has the potential to disrupt marine food webs and important ecosystem services like wild-caught fisheries. Figure 5: showing How CO2 leads to ocean acidification Ocean acidification is happening now, is measurable and will increase as more CO2 is emitted; it is likely that if CO2 emissions continue at the same rate ocean acidification will have a considerable influence on marine-based diets for billions of people worldwide. Royal Society (2005). 3.0.2 SEA LEVEL RISE The global sea level already has risen by seven inches over the past century. Sea level rise comes from two effects of rising temperature: the melting of glaciers and ice sheets, and the thermal expansion of water. If large ice sheets in the Antarctic melt, studies warn that there will be a significant rise in sea levels and decreases in ocean salinity. The thermal expansion of water simply means that water molecules take more space when they’re warmer, thermal expansion has accounted for about half of sea level rise since 1993. Global warming is projected to cause sea level rise to an average of 14 inches by 2050 and 47 inches or more by the end of the century, according to the 2011 Ocean Protection Council’s Interim Guidance on sea level rise. 3.0.3 COASTAL FLOODING Due to the warming of the earth, polar ice is melting leading to an increase in sea level. After the ice has melted, it finds its way into the ocean and increases the level of the ocean. As much as coastal floods have been recorded at the back, if the climate change is not controlled, coastal flooding will be persistent and ill even be recorded in areas they are less expected. 3.0.4 CORAL BLEACHING The warmer air and ocean surface temperatures brought on by climate change impact corals and alter coral reef communities by prompting coral bleaching events and altering ocean chemistry. These impacts affect corals and the many organisms that use coral reefs as habitat. Warm water temperatures brought on by climate change stress corals because they are very sensitive to changes in temperature. If water temperatures stay higher than usual for many weeks, the zooxanthellae they depend on for some of their food leave their tissue. Without zooxanthellae, corals turn white because zooxanthellae give corals their color. White, unhealthy corals are called BLEACHED CORALS. Bleached corals are weak and less able to combat disease. Figure 6: showing that not much CO2 is emitted in the past Figure 7: showing more CO2 in recent time due to anthropogenic activities Much of the carbon dioxide that enters the atmosphere dissolves into the ocean. In fact, the oceans have absorbed about 1/3 of the carbon dioxide produced from human activities since 1800 and about 1/2 of the carbon dioxide produced by burning fossil fuels. As carbon dioxide in the ocean increases, ocean pH decreases or becomes more acidic. With ocean acidification, corals cannot absorb the calcium carbonate they need to maintain their skeletons and the stony skeletons that support corals and reefs will dissolve. Already, ocean acidification has lowered the pH of the ocean by about 0.11 units. Moving the ocean's pH from 8.179 to a current pH of 8.069, which means the ocean is about 30% more acidic now than it was in 1751.If nothing is done to reduce carbon dioxide emissions into the atmosphere, ocean acidification will increase and more and more corals will be damaged or destroyed. Ocean acidification affects more than just corals. Snails, clams, and urchins also make calcium carbonate shells and ocean acidification negatively impacts these organisms as well. Just like corals, ocean acidification makes it harder for these organisms to absorb the calcium carbonate they need to build their shells. Brown, B.E. (1997) 3.1 GLOBAL WARMING RECORDS Earth has warmed and cooled many times since its formation about 4.6 billion years ago. Global climate changes were due to many factors, including massive volcanic eruptions, which increased carbon dioxide in the atmosphere; changes in the intensity of energy emitted by the Sun; and variations in Earth’s position relative to the Sun, both in its orbit and in the inclination of its spin axis. Variations in Earth’s position, known as Milankovitch cycles, combine to produce cyclical changes in the global climate. These cycles are believed to be responsible for the repeated advance and retreat of glaciers and ice sheets during the Pleistocene Epoch (1.8 million to 11,500 years before present), when Earth went through fairly regular cycles of colder “glacial” periods (also known as ice ages) and warmer “interglacial” periods. Glacial periods occurred at roughly 100,000-year intervals. An interglacial period began about 10,000 years ago, when the last ice age came to an end. Prior to that ice age, an interglacial period occurred about 125,000 years ago. During interglacial periods, greenhouse gases such as carbon dioxide and methane naturally increase in the atmosphere from increased plant and animal life. But since 1750 greenhouse gases have increased dramatically to levels not seen in hundreds of thousands of years, due to the rapid growth of the human population combined with developments in technology and agriculture. Human activity is now a powerful factor influencing Earth’s dynamic climate. The ice of the Polar Regions furnishes clues to the makeup of Earth’s ancient atmosphere. Ice cores that scientists have bored from the ice sheets of Greenland and Antarctica provide natural records of both temperature and atmospheric greenhouse gases going back hundreds of thousands of years. Layers in these ice cores created by seasonal snowfall patterns allow scientists to determine the age of the ice in each core. By measuring tiny air bubbles trapped in the ice and properties of the ice itself, scientists can estimate the temperature and amount of greenhouse gases in Earth’s past atmosphere at the time each layer formed. Based on this data, scientists know that greenhouse gases have now risen to levels higher than at any time in the last 650,000 years. Greenhouse gases are rising, and temperatures are rising too. Before the late 1800s, the average surface temperature of Earth was almost 15°C (59°F). Over the past 100 years, the average surface temperature has risen by about 0.7 Celsius degrees (1.3 Fahrenheit degrees), with most of the increase occurring since the 1970s. Scientists have linked even this amount of warming to numerous changes taking place around the world, including melting mountain glaciers and polar ice, rising sea level, more intense and longer droughts, more intense storms, more frequent heat waves, and changes in the life cycles of many plants and animals. Warming has been most dramatic in the Arctic, where temperatures have risen almost twice as much as the global average. 3.2 FUTURE GLOBAL WARMING Scientists project global warming to continue at a rate that is unprecedented in hundreds of thousands or even millions of years of Earth’s history. They predict considerably more warming in the 21st century, depending on the level of future greenhouse gas emissions. For a scenario (possible situation) assuming higher emissions in which emissions continue to increase significantly during the century scientists project further warming of 2.4-6.4⁰C (4.3-11.5⁰F) by the year 2100. For a scenario assuming lower emissions in which emissions grow slowly, peak around the year 2050, and then fall scientists project further warming of 1.1-2.9⁰C (1.9-5.2⁰F) by the year 2100. Melting polar ice and glaciers, as well as warming of the oceans, expands ocean volume and raises sea level, which will eventually flood some coastal regions and even entire islands. Patterns of rainfall are expected to change, with higher latitudes (closer to the poles) projected to receive more rainfall, and subtropical areas (such as the Mediterranean and southern Africa) projected to receive considerably less. Changes in temperature and precipitation patterns may damage food crops, disrupting food production in some parts of the world. Plant and animal species will shift their ranges toward the poles or to higher elevations seeking cooler temperatures, and species that cannot do so may become extinct. Increasing levels of carbon dioxide in the atmosphere also leads to increased ocean acidity, damaging ocean ecosystems. Human beings face global warming with a huge population at risk. The potential consequences are so great that many of the world’s leading scientists—and increasingly, politicians, business leaders, and other citizens—are calling for international cooperation and immediate action to counteract the problem. CHAPTER FOUR 4.0 RECOMMENDATION Due to the continuous change in climate as years go by, in the next few years, the earth may be witnessing a very high temperature that could highly be unbearable. In the light of this, if this can’t be completely stopped, it can be minimized through these: Anthropogenic activities such as release from industries, cars should be minimized by developing more climate-friendly machines. Release from industries and pollution by residents into the ocean should not be allowed. Strict laws should be made by the government to prevent people from excess deforestation. Incomplete combustion machines should be thoroughly checked and prevented. Ocean pollution should be checked. References Brown, B.E. 1997. Coral bleaching: Causes and consequences. Coral Reefs 16:S129-S138. Intergovernmental Panel on Climate Change (IPCC). 1996. Climate Change 1995: Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analysis. Cambridge University Press, Cambridge, MA. IPCC 2007 Climate Change 2007: The physical science basis. Summary for policymakers.Contribution of working group I to the fourth assessment report. The Intergovernmental Panel on Climate Change, http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf . Royal Society 2005 Ocean acidification due to increasing atmospheric carbon dioxide. Policy document 12/05 Royal Society, London. The Clyvedon Press Ltd, Cardiff. Mimura, N., L. Nurse, R.F. McLean, J. Agard, L. Briguglio, P. Lefale, R. Payet and G. Sem. 2007. Small islands. In: Climate Change 2007: Impacts, Adaptation and Vulnerability.Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panelon Climate Change. Edited by M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E.Hanson, Cambridge, UK: Cambridge University Press, Cambridge, UK,. pp 687-716. 16 | Page