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Tuesday, November 20, 2012

Grim Reports on Global Warming


World Bank, Intergovernmental Panel on Climate Change Seek to "wake up the world"

The astonishing damage wrought by Hurricane Sandy, which swept ashore on the East Coast of the United States on Sept. 29, is being punctuated by a series of reports that sow an apocalyptic vision if immediate and drastic action isn't taken.

A new study by the world's biggest climate modeling system, led by Dan Rowlands of Oxford University for the Intergovernmental Panel on Climate Change forecasts that a two-degree Celsius increase in global temperatures by the turn of the century would have a catastrophic effect:, with water stress in arid and semi-arid countries, more floods in low-lying coastal areas, coastal erosion in small island states, and the elimination of up to 30 percent of animal and plant species across the globe.

Also, in a grim report released today, which Jim Yong Kim, President of the World Bank Group said is designed "to shock the world into action," the World Bank is forecasting the inundation of coastal cities, increased risk of damage to food production leading to higher malnutrition, dry regions becoming dryer, wet regions becoming wetter, unprecedented heat waves, especially in the tropics, exacerbated water scarcity, more high-intensity tropical cyclones and irreversible loss of biodiversity including coral reef systems unless drastic action is taken to curb greenhouse gases and climate change.

The 119-page report, titled Turn Down the Heat: Why a 4°C Warmer World Must be Avoided, presents a frightening picture of a world "so different from the current one that it comes with high uncertainty and new risks that threaten our ability to anticipate and plan for future adaptation needs."

The report scolds the international community for lack of action which "not only risks putting prosperity out of reach of millions of people in the developing world, it threatens to roll back decades of sustainable development."

To those who deny that climate change is real and taking place, Kim warns that: "The science is unequivocal that humans are the cause of global warming, and major changes are already being observed: global mean warming is 0.8°C above pre industrial levels; oceans have warmed by 0.09°C since the 1950s and are acidifying; sea levels rose by about 20 cm since pre-industrial times and are now rising at 3.2 cm per decade; an exceptional number of extreme heat waves occurred in the last decade; major food crop growing areas are increasingly affected by drought."

The report is focused on developing countries although it notes that developed countries are also vulnerable and at serious risk of major damage, such as the arrival of Hurricane Sandy, with damage that could cost as much as US$50 billion. A series of recent extreme events worldwide continues to highlight the vulnerability of not only the developing world but even wealthy industrialized countries.

"No nation will be immune to the impacts of climate change," the World Bank report notes "However, the distribution of impacts is likely to be inherently unequal and tilted against many of the world's poorest regions, which have the least economic, institutional, scientific, and technical capacity to cope and adapt.

The warming that will occur in the tropics is larger when compared to the historical range of temperature and extremes to which human and natural ecosystems have adapted and coped. The projected emergence of unprecedented high-temperature extremes in the tropics will consequently lead to significantly larger impacts on agriculture and ecosystems. Sea level rises in the tropics are likely to be 15 to 20 percent larger in the tropics than the global mean, meaning that some of the world's most fertile lands – and cities including Bangkok, Jakarta and others are likely to be inundated and floods will become the norm.

Increases in tropical cyclone intensity are likely to be felt disproportionately in low-latitude regions, such as the megastorms that hit Myanmar and Bangladesh over the past three or four years, killing tens of thousands of people.

"A world in which warming reaches 4°C above preindustrial levels (hereafter referred to as a 4°C world), would be one of unprecedented heat waves, severe drought, and major floods in many regions, with serious impacts on human systems, ecosystems, and associated services," the report continues.

While it says 4°C can still be avoided: numerous studies show that there are technically and economically feasible emissions pathways to hold warming likely below 2°C, the political will to take such measures is not there at this time. While Hurricane Sandy undoubtedly played a role in President Barack Obama's reelection, there is no indication that he plans to make climate change a major issue in his final four-year term. China and India, both on breakneck economic development trajectories, do not appear to be strongly committed to holding back on increasing production of greenhouse gases.

"…the level of impacts that developing countries and the rest of the world experience will be a result of government, private sector, and civil society decisions and choices, including, unfortunately, inaction," the World Bank study notes.

According to the Intergovernmental Panel on Climate Change, "The unequivocal effects of greenhouse gas emission–induced change on the climate system…have continued to intensify, more or less unabated." The present concentration of CO2 in the atmosphere is higher than paleoclimatic and geologic evidence indicates has occurred at any time in the last 15 million years. The global mean temperature has continued to increase and is now about 0.8°C above preindustrial levels.

The global oceans have continued to warm, with about 90 percent of the excess heat energy trapped by the increased greenhouse gas concentrations since 1955 stored in the oceans as heat. The average increase in sea levels around the world over the 20th century has been about 15 to 20 centimeters. Over the last decade the average rate of sea-level rise has increased to about 3.2 cm per decade. Should this rate remain unchanged, this would mean over 30 cm of additional sea-level rise in the 21st century.

The Greenland and Antarctic ice sheets are losing ice faster, which could add substantially to sea-level rise, with the annual rate of ice lost more than tripling just since the 1993–2003 period "If ice sheet loss continues at these rates, without acceleration, the increase in global average sea level due to this source would be about 15 cm by the end of the 21st century. A clear illustration of the Greenland ice sheet's increasing vulnerability to warming is the rapid growth in melt area observed since the 1970s. As for Arctic sea ice, it reached a record minimum in September 2012, halving the area of ice covering the Arctic Ocean in summers over the last 30 years.

Extreme heat waves have increased both in frequency and intensity, with extreme precipitation and drought also increasing in intensity and/or frequency. The Russian heat wave of 2010 is estimated to have cost 55,000 lives and 25 percent of annual crops, burned more than 1 million hectares, and delivered economic losses of about US$15 billion, 1 percent Russia's gross domestic product.

These heat waves normally would have been expected only once every several hundred years, the report says. They have hit the United States, Europe and Russia in the last decade. Observations indicate a tenfold increase in the surface area of the planet experiencing extreme heat since the 1950s. The 2012 drought that hit the US Middle West affected 80 percent of the country's agricultural land, cutting badly into US exports.

One of the most serious consequences of rising carbon dioxide concentration in the atmosphere occurs when it dissolves in the ocean and results in acidification. Evidence is already emerging of the adverse consequences of acidification for marine organisms and ecosystems, combined with the effects of warming, overfishing, and habitat destruction.

"A 4°C world will pose unprecedented challenges to humanity," the report concludes. "It is clear that large regional as well as global scale damages and risks are very likely to occur well before this level of warming is reached. This report has attempted to identify the scope of these challenges driven by responses of the Earth system and various human and natural systems.

"Although no quantification of the full scale of human damage is yet possible, the picture that emerges challenges an often-implicit assumption that climate change will not significantly undermine economic growth. It seems clear that climate change in a 4°C world could seriously undermine poverty alleviation in many regions.

"This is supported by past observations of the negative effects of climate change on economic growth in developing countries. While developed countries have been and are projected to be adversely affected by impacts resulting from climate change, adaptive capacities in developing regions are weaker. The burden of climate change in the future will very likely be borne differentially by those in regions already highly vulnerable to climate change and variability. Given that it remains uncertain whether adaptation and further progress toward development goals will be possible at this level of climate change, the projected 4°C warming simply must not be allowed to occur—the heat must be turned down. Only early, cooperative, international actions can make that happen."

Dipetik dari - Asia Sentinel

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