[News] from [guardian.co.uk]
[Environmnt > Ozone layer]
Antarctica may heat up dramatically as ozone hole repairs, warn scientists
As blanket of ozone over southern pole seals up, temperatures on continent could soar by 3C, increasing sea level rise by 1.4m
Alok Jha, green technology correspondent
guardian.co.uk, Tuesday 1 December 2009 09.06 GMT Article history
The hole in the Earth's ozone layer has shielded Antarctica from the worst effects of global warming until now, according to the most comprehensive review to date of the state of the Antarctic climate. But scientists warned that as the hole closes up in the next few decades, temperatures on the continent could rise by around 3C on average, with melting ice contributing to a global sea-level increases of up to 1.4m.
The western Antarctic peninsula has seen rapid ice loss as the world has warmed, but other parts of the continent have paradoxically been cooling, with a 10% increase in ice in the seas around the region in recent decades. Many climate change sceptics have used the Antarctic cooling as evidence against global warming.
But John Turner of the British Antarctic Survey said scientists are now "very confident" that the anomaly had caused by the ozone hole above Antarctica. "We knew that, when we took away this blanket of ozone, we would have more ultra-violet radiation. But we didn't realise the extent to which it would change the atmospheric circulation of the Antarctic."
These changes in weather have increased winds in the Southern Ocean region and meant that a large part of the continent has remained relatively cool compared with the western peninsula. But because the the CFC gasses that caused the ozone hole now been banned, scientists expect the damage to repair itself within the next 50-60 years. By then the cooling effect will have faded out and Turner said the Antarctic would face the full effects of global warming. This means an increase in average air temperatures of around 3C and a reduction in sea ice by around a third.
The biggest threat to the continent comes from warming seas. Robert Binschadler, a glaciologist at Nasa who monitors Antarctic ice sheets, said: "The heat in the ocean is getting underneath the floating ice shelves, these floating fringes of the ice sheet that are hundreds of metres thick. That warm water is melting the underside of the ice shelf, reducing the buttressing effect." Thinning of the ice shelf at the fringes leads to glaciers moving more quickly.
The retreat of ice from Antarctica has contributed around 10% to global sea-level rise in recent decades. "The danger is that this warmer water will get under these ice shelves and cause the ice streams to get faster and feed ice out into the ocean," said Turner.
Published by the Scientific Committee on Antarctic Research (SCAR), a coalition of international experts that coordinates international research in the region, the report has been published to give negotiators in Copenhagen the most up-to-date science available. "Everything is connected — Antarctica may be a long way away but it is an important part of the Earth's system," said Colin Summerhayes, executive director of SCAR. "It contains 90% of the world's ice, 70% of the world's fresh water and that is enough, if it melts, to raise sea levels by 63m."
SCAR's review also corroborated recent work by Stefan Rahmstorf, a climate scientist at the Potsdam Institute for Climate Impacts Research in Germany, that average sea-level rise will be closer to 1.4m by the end of the century. This is higher than the rise predicted by the Intergovernmental Panel on Climate Change (IPCC) in 2007, said Turner, because the IPCC's forecasts did not include the impact of melting ice sheets on sea level rises. Many of the climate models used by the IPCC have also not taken the ozone hole into account in their simulations.
[Environment > Emission trading]
Australian opposition dumps its leader over carbon trading bill
Liberals choose new leader as climate change policy splits party, bringing country closer to early elections
Associated Press, Sydney
guardian.co.uk, Tuesday 1 December 2009 10.34 GMT Article history
Australia's plans to become one of the first nations with a carbon trading system to cut greenhouse gas emissions were dealt a blow today when the main opposition party dumped its leader who supported the idea and chose one who vowed to vote it down.
A tumultuous day in politics also means the country could also be one step closer to early elections, with policy differences over global warming placing it as a central issue of the coming campaign.
Debate in the senate on the government's plans for an emissions trading system continued today as the conservative Liberal party ejected one leader from the post and elected another. A final vote could come at almost any time.
The conservatives have split bitterly and publicly in the past week over the bill, culminating in the leadership challenge. Right-leaning Tony Abbott won the vote, ousting Malcolm Turnbull, who had struck a deal with the government to support the bill.
Abbott said his party would now move to defer the bill until after next week's UN global summit on climate change in Copenhagen, and possibly longer. If the bill is not deferred, the opposition would vote against it this week in the senate, he said. The government lacks a majority in the senate, and the bill will almost certainly fail if the Liberals vote against it.
If the bill is defeated, the prime minister, Kevin Rudd, is handed a trigger to call an election at any time under constitutional rules meant to be the ultimate resolution to any deadlock between Australia's two houses of parliament.
Rudd is unlikely to call an election immediately, partly because of the Christmas-New Year holiday season. Elections are, however, due sometime next year, and opinion polls consistently show the prime minister rating highly.
Rudd wants the legislation passed before the Copenhagen summit to help portray him as a world leader on tackling climate change.
Australia is a small greenhouse gas polluter in global terms, but one of the worst per capita because it relies heavily for its electricity on its abundant reserves of coal, which also make it the world's largest exporter of the polluting fuel. As the driest continent after Antarctica, it is also considered one of the most vulnerable countries to climate change.
The European Union has a carbon trading system, as do some US states. Canada and New Zealand are among countries considering them.
Under the government's plan, an annual limit would be placed on the amount of greenhouse gases allowed to be pumped into the atmosphere and permits would be issued to regulate that ceiling. The permits could be bought and sold, setting up a market system that makes reducing emissions potentially profitable for polluting companies.
Rudd wants to slash Australia's emissions by up to 25% below 2000 levels by 2020 if a tough emissions reduction deal is struck in Copenhagen.
Abbott said the proposed system amounts to a massive new tax that would curb economic growth — shrugging off opinion polls that say most Australians want the government to act against climate change.
"I am really not frightened of an election on this issue," Abbott told reporters.
Rudd, speaking in Washington shortly before Abbott was elected his party's leader, said the conservatives were dragging their heels on the issue and that "further delay equals denial on climate change".
[Environmnt > Ozone layer]
Antarctica may heat up dramatically as ozone hole repairs, warn scientists
As blanket of ozone over southern pole seals up, temperatures on continent could soar by 3C, increasing sea level rise by 1.4m
Alok Jha, green technology correspondent
guardian.co.uk, Tuesday 1 December 2009 09.06 GMT Article history
The hole in the Earth's ozone layer has shielded Antarctica from the worst effects of global warming until now, according to the most comprehensive review to date of the state of the Antarctic climate. But scientists warned that as the hole closes up in the next few decades, temperatures on the continent could rise by around 3C on average, with melting ice contributing to a global sea-level increases of up to 1.4m.
The western Antarctic peninsula has seen rapid ice loss as the world has warmed, but other parts of the continent have paradoxically been cooling, with a 10% increase in ice in the seas around the region in recent decades. Many climate change sceptics have used the Antarctic cooling as evidence against global warming.
But John Turner of the British Antarctic Survey said scientists are now "very confident" that the anomaly had caused by the ozone hole above Antarctica. "We knew that, when we took away this blanket of ozone, we would have more ultra-violet radiation. But we didn't realise the extent to which it would change the atmospheric circulation of the Antarctic."
These changes in weather have increased winds in the Southern Ocean region and meant that a large part of the continent has remained relatively cool compared with the western peninsula. But because the the CFC gasses that caused the ozone hole now been banned, scientists expect the damage to repair itself within the next 50-60 years. By then the cooling effect will have faded out and Turner said the Antarctic would face the full effects of global warming. This means an increase in average air temperatures of around 3C and a reduction in sea ice by around a third.
The biggest threat to the continent comes from warming seas. Robert Binschadler, a glaciologist at Nasa who monitors Antarctic ice sheets, said: "The heat in the ocean is getting underneath the floating ice shelves, these floating fringes of the ice sheet that are hundreds of metres thick. That warm water is melting the underside of the ice shelf, reducing the buttressing effect." Thinning of the ice shelf at the fringes leads to glaciers moving more quickly.
The retreat of ice from Antarctica has contributed around 10% to global sea-level rise in recent decades. "The danger is that this warmer water will get under these ice shelves and cause the ice streams to get faster and feed ice out into the ocean," said Turner.
Published by the Scientific Committee on Antarctic Research (SCAR), a coalition of international experts that coordinates international research in the region, the report has been published to give negotiators in Copenhagen the most up-to-date science available. "Everything is connected — Antarctica may be a long way away but it is an important part of the Earth's system," said Colin Summerhayes, executive director of SCAR. "It contains 90% of the world's ice, 70% of the world's fresh water and that is enough, if it melts, to raise sea levels by 63m."
SCAR's review also corroborated recent work by Stefan Rahmstorf, a climate scientist at the Potsdam Institute for Climate Impacts Research in Germany, that average sea-level rise will be closer to 1.4m by the end of the century. This is higher than the rise predicted by the Intergovernmental Panel on Climate Change (IPCC) in 2007, said Turner, because the IPCC's forecasts did not include the impact of melting ice sheets on sea level rises. Many of the climate models used by the IPCC have also not taken the ozone hole into account in their simulations.
[Environment > Emission trading]
Australian opposition dumps its leader over carbon trading bill
Liberals choose new leader as climate change policy splits party, bringing country closer to early elections
Associated Press, Sydney
guardian.co.uk, Tuesday 1 December 2009 10.34 GMT Article history
Australia's plans to become one of the first nations with a carbon trading system to cut greenhouse gas emissions were dealt a blow today when the main opposition party dumped its leader who supported the idea and chose one who vowed to vote it down.
A tumultuous day in politics also means the country could also be one step closer to early elections, with policy differences over global warming placing it as a central issue of the coming campaign.
Debate in the senate on the government's plans for an emissions trading system continued today as the conservative Liberal party ejected one leader from the post and elected another. A final vote could come at almost any time.
The conservatives have split bitterly and publicly in the past week over the bill, culminating in the leadership challenge. Right-leaning Tony Abbott won the vote, ousting Malcolm Turnbull, who had struck a deal with the government to support the bill.
Abbott said his party would now move to defer the bill until after next week's UN global summit on climate change in Copenhagen, and possibly longer. If the bill is not deferred, the opposition would vote against it this week in the senate, he said. The government lacks a majority in the senate, and the bill will almost certainly fail if the Liberals vote against it.
If the bill is defeated, the prime minister, Kevin Rudd, is handed a trigger to call an election at any time under constitutional rules meant to be the ultimate resolution to any deadlock between Australia's two houses of parliament.
Rudd is unlikely to call an election immediately, partly because of the Christmas-New Year holiday season. Elections are, however, due sometime next year, and opinion polls consistently show the prime minister rating highly.
Rudd wants the legislation passed before the Copenhagen summit to help portray him as a world leader on tackling climate change.
Australia is a small greenhouse gas polluter in global terms, but one of the worst per capita because it relies heavily for its electricity on its abundant reserves of coal, which also make it the world's largest exporter of the polluting fuel. As the driest continent after Antarctica, it is also considered one of the most vulnerable countries to climate change.
The European Union has a carbon trading system, as do some US states. Canada and New Zealand are among countries considering them.
Under the government's plan, an annual limit would be placed on the amount of greenhouse gases allowed to be pumped into the atmosphere and permits would be issued to regulate that ceiling. The permits could be bought and sold, setting up a market system that makes reducing emissions potentially profitable for polluting companies.
Rudd wants to slash Australia's emissions by up to 25% below 2000 levels by 2020 if a tough emissions reduction deal is struck in Copenhagen.
Abbott said the proposed system amounts to a massive new tax that would curb economic growth — shrugging off opinion polls that say most Australians want the government to act against climate change.
"I am really not frightened of an election on this issue," Abbott told reporters.
Rudd, speaking in Washington shortly before Abbott was elected his party's leader, said the conservatives were dragging their heels on the issue and that "further delay equals denial on climate change".
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