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Thursday, April 8, 2004

Climate Meltdown: Greenland ice cap to raise sea levels

The issue bigger than terrorism: climate change is on the agenda and will affect every person and country. Greenhouse Gas Emissions are a primary cause of global warming which is a major driving force for climate change. And conservative politicians like George Bush (USA) and John Howard (Australia) have their heads in the sand in Iraq.

A new study by a senior British climatologist, Jonathan Gregory, published in Nature and reported on in New Scientist (Greenland ice cap 'doomed to meltdown'), predicts that the Greenland ice sheet is all but doomed to melt away to nothing causing global sea levels to rise by seven metres, flooding most of the world's coastal regions.

Gregory warns that, if his calculations are correct, "the Greenland ice sheet is likely to be eliminated unless much more substantial reductions in [carbon dioxide] emissions are made than those envisaged" so far by scientists or politicians.

Snowfall onto the ice cap at present is balanced by meltwater and icebergs draining away into the Atlantic Ocean. The icecap is 3,000 metres high and contains 2.85 million cubic kilometres of ice. Gregory, from the Hadley Centre for Climate Prediction and Research in England, and co-author Philippe Huybrechts, a glaciologist at the Free University in Brussels, Belgium, calculate that if the island warms by an annual average of 3 degrees Celsius, melting will exceed snowfall and the ice sheet will begin to disappear.

The melting will be almost impossible to stop, argues Gregory. As the ice melts, the cap's surface will sink to lower altitudes, warming the surface further, reducing snowfall and accelerating melting. Runaway melting on Greenland could start within 50 years, and it will "probably be irreversible this side of a new ice age". Although total meltdown is likely to take at least 1000 years.

This latest study and analysis by Gregory and Huybrechts significantly strengthens their predictions, which they first put forward in 1999. In the latest study 35 different predictions of climate change from seven global climate models were examined. All but one forecast that the threshold for runaway melting on Greenland will be exceeded, in some cases as early as 2035.

If warming stabilises at 3 degrees Celsius, the ice sheet could survive for several thousand years. But if temperatures rise by 8 degrees Celsius, which several scenarios predict, then it would disappear in 1000 years.

Coastal areas inundated

The disintegration of the world's second largest ice cap would have a catastrophic effect on global sea levels, with the flooding of many coastal cities and coastal farmland. The rise in sea levels would, however, be gradual. This does not help the many Pacific Islanders, such as Tuvalu, or the many people in Bangladesh who will need relocating.

Another concern is the effect all the fresh meltwater in the North Atlantic could have on the Great Ocean Conveyor Belt. The operation of this global ocean current system is still poorly understood, but predictions of the current system being disrupted in the North Atlantic may lead to the onset of a new Ice Age with Siberian conditions for Britain and Europe.

Increased Arctic Sea Ice melt points to drier North American West Coast

Current research reported on in New Scientist (Arctic melt may dry out US west coast) on Arctic sea ice melts indicates that annual rainfall may drop by as much as 30 percent on the US/Canada west Coast. This will lead inevitably to a water crisis with water rationing a necessity and reduced water for irrigation. Natural ecosystems would be forced to adapt to a drier climate.

Jacob Sewall and Lisa Cirbus Sloan from the University of California at Santa Cruz first used a climate model to work out how sea ice cover was likely to change through the rest of the year. These values for sea ice cover and the resulting sea surface temperatures were then plugged into a global climate model to see which areas of the world would be most affected. While Europe was affected relatively lightly, they found that the sea ice changes are likely to mean significantly fewer storms will pass over the west coast of the US.

Sewall is careful to point out that they have only modelled the impact of reduced Arctic sea ice cover. Other climate factors, such as increasing greenhouse gases, might interact with melting Arctic sea ice, reducing, or even exacerbating, any changes in rainfall.

Other climatologists such as Marika Holland, from the National Center for Atmospheric Research in Boulder, Colorado, says the research "needs more work to become a prediction," but points out the study "highlights the importance of regional changes associated with a distant location".

Kyoto Protocol Hamstrung

Greenhouse gas emissions are now the recognised cause of climate change, and are largely a result of industrialisation and the combustion of fossil fuels for energy. The Kyoto Protocol was signed as a framework agreement in 1997 under which rich industrialised countries would curb emissions of "greenhouse" gases - carbon pollution from the burning of fossil fuels that scientists say is dangerously affecting Earth's fragile climate system.

It took four years to negotiate the protocol's highly detailed rulebook but by that time the United States had quit the process under a controversial decision by President George W Bush. The US withdrawal has deprived Kyoto of support from its biggest carbon polluter and left it perilously short of failing to muster enough support to take effect. Under the protocol's rules, ratification by Russia is now essential for the deal to become an international treaty.

As reported by AAP on the ABC network in March, United Nations Secretary-General, Kofi Annan, warned that the first signs of disastrous climate change may already be visible in a message to mark the 10th anniversary of the coming into force of Kyoto's parent treaty, the United Nations Framework Convention on Climate Change (UNFCCC).

"Some of the effects of climate change are by now inevitable and, indeed, we may already be seeing - in the increased incidence of drought, floods and extreme weather events that many regions are experiencing - some of the devastation that lies ahead," he said. Kyoto's "lack of entry into force remains a major hurdle to effective action. I call again on those countries that have not yet ratified the protocol to do so, and show that they are truly committed to shouldering their global responsibilities."

While the USA tops the list for total Green House Gas emissions at 19.074 Tonnes per capita per year of CO2, Australia with its reliance on abundant coal reserves and coal fired power stations is close behind with 16.902 Tonnes per capita per year of CO2. According to UN statistics Australia had a 24.9 per cent increase in CO2 emissions between 1990 and 2001 (see Note 1).

In Australia, a 2 per cent Mandatory Renewable Energy Target (MRET) was introduced in 1998 which has kick started a solar, wind and bioenergy industry. However, a 10% MRET by 2010 is the international standard which environmental groups are calling for the Australian Government to implement. (Campaigners ask Howard for more Renewable Energy) Australia, like the USA, refuses to sign the Kyoto treaty to control green house gas emissions.

Note 1 : Report on the national greenhouse gas inventory data from Annex I Parties for the period 1990–2001 (PDF). See Table 6. Total anthropogenic CO2 emissions, excluding land-use change and forestry, 1990 and 1995–2001 shows Australia on 24.9% increase over the period. Table 8. Total anthropogenic N2O emissions, 1990 and 1995–2001 shows Australia increasing emissions by 37.6%. (see UN statistics

The tonnes per capita figures come from New Internationalist 357

More Information:

* United Nations Framework Convention on Climate Change
* United Nations Environment Program has some great graphics and maps on Greenhouse Gas Emissions
* Friends of the Earth Australia Climate Justice Tour (April-May 2004)
* Rising Tide climate Justice Network
* The discovering of Global Warming

Article rescued from Melbourne Indymedia web archive