Giant Antarctic ice sheet hangs by an icy thread
31 Jan 2009, 1425 hrs
WELLINGTON: The Wilkins Ice Shelf, a giant Antarctic ice sheet, is literally hanging by an icy thread, and can break-off anytime.
According to a report in stuff.co.nz, if it goes, the Wilkins Ice Shelf, which is the size of Jamaica, would become the 10th Antarctic ice shelf to recede or vanish into the sea since 1950.
Scientists think the loss of Antarctic ice shelves such as Wilkins will let inland glaciers slide to the ocean faster, pumping vast quantities of ice into the sea and contributing to sea-level rises.
Sea-level rises are also caused by thermal expansion of the oceans as they become warmer.
The Intergovernmental Panel on Climate Change (IPCC) has predicted a sea-level rise of up to 59 centimeters by the end of the century.
But, it did not include the possible effects of melting ice sheets and said it could not yet predict the full extent of a future sea-level rise.
Councils are already preparing for rising sea levels and resulting coastal erosion, according to Iain Dawe, regional council hazards analyst, Greater Wellington, New Zealand.
Options include hazard setback zones, a retreat from the coast, and even building homes on piles so they can be easily moved back from the sea.
Dawe said that planners are plagued by uncertainty over how much seas may rise. The Kapiti Coast faces real challenges, while Wellington's south coast is less at risk.
"On big gravel beaches, the gravel will just move further up the shore and absorb the impact," he said.
Rising sea levels will increase the chance of flooding from storm surge and could lead to increased premiums for coastal dwellers, according to Insurance Council insurance manager John Lucas.
Rising sea levels also threaten low-lying islands in the Pacific and Indian oceans.
Victoria University climate change professor Martin Manning, who was on the climate panel, said that new studies talk of sea-level rises of between 1.6 meters and 2 meters by 2100.
"The bottom line is that things are happening quite quickly for example, the fact that we have only seen rapid change in the ice sheets since 2003," he said.
According to Waikato University oceanographer Willem de Lange, "There has long been a pattern of ice shelves building up and collapsing. All it shows is that the world has got warmer since the last ice age."
31 Jan 2009, 1425 hrs
WELLINGTON: The Wilkins Ice Shelf, a giant Antarctic ice sheet, is literally hanging by an icy thread, and can break-off anytime.
According to a report in stuff.co.nz, if it goes, the Wilkins Ice Shelf, which is the size of Jamaica, would become the 10th Antarctic ice shelf to recede or vanish into the sea since 1950.
Scientists think the loss of Antarctic ice shelves such as Wilkins will let inland glaciers slide to the ocean faster, pumping vast quantities of ice into the sea and contributing to sea-level rises.
Sea-level rises are also caused by thermal expansion of the oceans as they become warmer.
The Intergovernmental Panel on Climate Change (IPCC) has predicted a sea-level rise of up to 59 centimeters by the end of the century.
But, it did not include the possible effects of melting ice sheets and said it could not yet predict the full extent of a future sea-level rise.
Councils are already preparing for rising sea levels and resulting coastal erosion, according to Iain Dawe, regional council hazards analyst, Greater Wellington, New Zealand.
Options include hazard setback zones, a retreat from the coast, and even building homes on piles so they can be easily moved back from the sea.
Dawe said that planners are plagued by uncertainty over how much seas may rise. The Kapiti Coast faces real challenges, while Wellington's south coast is less at risk.
"On big gravel beaches, the gravel will just move further up the shore and absorb the impact," he said.
Rising sea levels will increase the chance of flooding from storm surge and could lead to increased premiums for coastal dwellers, according to Insurance Council insurance manager John Lucas.
Rising sea levels also threaten low-lying islands in the Pacific and Indian oceans.
Victoria University climate change professor Martin Manning, who was on the climate panel, said that new studies talk of sea-level rises of between 1.6 meters and 2 meters by 2100.
"The bottom line is that things are happening quite quickly for example, the fact that we have only seen rapid change in the ice sheets since 2003," he said.
According to Waikato University oceanographer Willem de Lange, "There has long been a pattern of ice shelves building up and collapsing. All it shows is that the world has got warmer since the last ice age."
