Global warming is creating MORE glaciers: Antarctic sea ice reaches a record high because of climate change, scientists claim
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Earlier this year, global warming was blamed for the 'irreversible retreat' of west Antarctic glaciers.
But now scientists claim that warming of the planet is in fact behind a paradoxical growth in South Pole sea ice.
The comments come as Antarctica's sea ice set a record this week, reaching 815,448 square miles (1,312,000 square km) of ice above its normal range.
Earlier this year, global warming was blamed for the 'irreversible retreat' of west Antarctic glaciers. But now scientists claim that warming of the planet is in fact behind a paradoxical expansion in South Pole sea ice
Scientists believe the shift is caused by water melting from beneath the Antarctic ice shelves and re-freezing back on the surface.
'The primary reason for this is the nature of the circulation of the Southern Ocean — water heated in high southern latitudes is carried equatorward, to be replaced by colder waters upwelling from below, which inhibits ice loss,' Mark Serreze, director of the National Snow and Ice Data Centre, told Harold Ambler at Talking About the Weather.
However Nasa scientist Walt Meier said that growing Antarctic sea ice coverage is less significant a measure than declining Arctic sea ice coverage when assessing climate change.
'While the Arctic has seen large decreases through the year in all sectors, the Antarctic has a very regional signal – with highs in some areas and lows in others,' Dr Meier told the Daily Caller.
Despite ice coverage increasing in some areas, Nasa claims that in a few hundred years the irreversible melt that has already started from the Amundsen Sea sector of the West Antarctica ice sheet, pictured, has now 'passed the point of no return' and could eventually add four to 12 feet (1.2 to 3.7 metres) to current sea levels
On the left here is the elevation of the region, while on the right the various glaciers that will be affected by the melting of the Amundsen Sea region. Nasa scientist Walt Meier said that growing Antarctic sea ice coverage is less significant a measure than declining Arctic sea ice coverage when assessing climate change
'And of course, the Arctic volume is decreasing substantially through the loss of old ice. The Antarctic, which has very little old ice, hasn't much of a volume change, relatively speaking.'
Last year, a team from the Royal Netherlands Meteorological Institute found that the fresh water melting from the Antarctic ice sheets had a relatively low density compared to the denser salty seawater.
This means that the water accumulates and freezes in the top layer of the ocean during the summer months.
Surrounded by North America, Greenland and Eurasia, the Arctic ice cap floats on the ocean, not land. It has lost a large amount of its older, thicker sea ice over the last 30 years, making it more vulnerable to the warming trend.
Last year, a team from the Royal Netherland's Meteorological Institute found that the fresh water melting from the Antarctic ice sheets had a relatively low density compared to the denser salty seawater. This means that it accumulates in the top layer of the ocean during the summer months
The Antarctic, however, is a continent circled by open waters that lets sea ice expand during the winter but also offers less shelter during the melt season.
The Dutch report found that despite the increase in surface ice expansion each winter, the total mass of ice around Antarctica is continuing to shrink because of the underwater ice melt.
In May, Nasa scientists told reporters that vast glaciers in West Antarctica seem to be locked in an irreversible thaw linked to global warming that may push up sea levels for centuries.
In a few hundred years they say the irreversible melt that has already started could eventually add four to 12 feet (1.2 to 3.7 metres) to current sea levels.
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