Saturday, 7 January 2017

Antarctic iceberg abut to break off

Huge Antarctic iceberg about to break off and slide into the sea

It isn’t clear what damage the huge iceberg will do to the surrounding landscape




ice.jpg

6 January, 2016

A huge iceberg, one of the biggest ever recorded, is about to break off Antarctica.

Part of the Larsen C ice shelf is now hanging by only a relative thread after a crack expanded quickly last month. There is now only about 20 kilometres of ice attaching it to Antarctica – and when it splits off, it will form an iceberg as big as a US state or Trinidad and Tobago.

When that happens, it will radically change the landscape of the Antarctic Peninsula, according to scientists who are tracking it. It could even lead to the wider break-up of the entire shelf, according to a statement from the scientists.

In all, the shelf will shed an area more than 1,930 square miles, scientists from Project Midas at the University of Wales said.

Climate change ‘pause’ does not exist, scientists show, in wounding blow for global warming denialists




Ice shelves are areas of ice, often huge, floating around on the sea at the end of glaciers.

If they are lost, they could allow those glaciers to slide faster towards the sea as temperatures rise because of global warming. That will help contribute towards rising sea levels and could have catastrophic effects across the world.

Several ice shelves – including Larsen B – have disintegrated in recent years as a result of climate change.

Andrew Fleming, remote sensing manager at the British Antarctic Survey who also tracks the Larsen C, said the ice was being thawed both by warmer air above and by warmer waters below.

In some cases, big icebergs simply float around Antarctica for years, causing little threat to shipping lanes as they melt. More rarely, icebergs drift as far north as South America.

"Larsen B shattered like car safety glass into thousands and thousands of pieces,” he said. “It disappeared in the space of about a week.”


Last year was easily the warmest on record, as a result of greenhouse gases and the El Nino weather event. Changes to sea temperatures and levels are likely to be one of the most significant results of that change, which could in turn bring extreme alterations in the weather

From RT


Larsen C ice shelf schism may form giant Antarctic iceberg (PHOTOS, VIDEO)


Larsen C ice shelf schism may form giant Antarctic iceberg (PHOTOS, VIDEO)
© NASA


RT,
6 January, 2016


A glacier more than 80 times the size of Manhattan is on the brink of splintering from Antarctica's Larsen C ice shelf and floating off into the ocean.

Over time, a rift has steadily formed along the massive ice sheet, which lies in the Weddell Sea near the northwest of the Antarctic.

Pictures released by NASA last November showed a 100-meter (328ft) wide and 500-meter deep (1640ft) crack slicing the incredible sub-zero temperature environment.

According to Project Midas, a UK research group documenting the effects of global warming in the area, 10 percent of the overall Larsen C ice mass is now close to calving into the sea.

It could mean the creation of a 5,000 sq km (193 sq mile) iceberg.


In a statement, Project Midas revealed that the large iceberg is connected to the Larsen C mainland only along a 20km (12.5 mile) stretch. It added: “This [separation] will fundamentally change the landscape of the Antarctic Peninsula.”

The rift on Larsen C has grown even further, and the ice shelf is now poised to calve:

The threat of massive glacial upheaval has not only put the future of the ice shelf at risk, but also brought danger to the door of those carrying out research at the Weddell Sea location, according to the British Antarctic Survey.

The calving of this large iceberg could be the first step of the collapse of Larsen C ice shelf, which result in the disintegration of a huge area of ice into a number of icebergs and smaller fragments,” said Professor David Vaughan, director of science at the organization.

© NASA

He said researchers are no longer camping on the ice due to concerns over the ice mass’ stability: “Because of the uncertainty surrounding the stability of the Larsen C ice shelf, we chose not to camp on the ice this season. Researchers can now only do day trips from our Rothera Research Station with an aircraft nearby on standby.”

In 2002, two-thirds of the nearby Larsen B ice shelf collapsed in less than six weeks. NASA compared the sudden environmental change to a “car accelerating from 55 to 440mph”.


News of the impending Larsen C split comes as a study by the University of California and a group of scientists from non-profit group Berkeley Earth revealed the rate of ocean warming has risen from 0.07 to 0.12 degrees Celsius in the last 19 years.


The analysis also found that the switch over from ship to buoy temperature measurement created a ‘cooling bias’ which led to talk of a climate change slowdown or “global warming hiatus”.

Published in the journal Science Advances, the study suggests the switch over from ship to buoy measurement lead to varying results from three major climate research centers: the Hadley Centre, the National Oceanic and Atmospheric Administration, and Japan’s meteorological agency.

These results serve as a robust, independent validation of the NOAA temperature record and show us that the new NOA temperature record is probably the best estimate of global ocean temperatures for the last 15 years,” 
said Zeke Hausfather, a UC Berkeley graduate and lead author of the paper.

They show that NOAA scientists weren’t cooking the books.”




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