About these ads

Global warming: Greenland, West Antarctic ice sheets losing volume at record pace

Loss of ice volume doubles in just 5 years

hlj

Arctic and Antarctic ice sheets are losing volume at a record pace. bberwyn photo.

By Bob Berwyn

FRISCO —Detailed new data from satellites and other sources show the world’s major ice sheets losing volume at a record pace, faster than at any time since satellite measurements started about 20 years ago.

Since 2009, the rate of volume loss from the Greenland Ice Sheet has doubled, and the rate of volume loss from the West Antarctic Ice Sheet has tripled, according to the new findings from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research. Continue reading

About these ads

Climate: Melting Antarctic ice sheets likely to become big factor in sea level rise sooner than thought

‘Official’ IPCC sea level estimates may be too low

kjg

Antarctica ice is becoming a bigger factor in global sea level rise. bberwyn photo.

By Bob Berwyn

FRISCO — Although Antarctica’s vast ice sheets are only a small factor in global sea level rise right now, that’s likely to change in coming decades, scientists said after a new analysis of ocean temperatures around the frozen continent.

“If greenhouse gases continue to rise as before, ice discharge from Antarctica could raise the global ocean by an additional 1 to 37 centimeters in this century already,” says lead author Anders Levermann, with the Potsdam Institute for Climate Impact Research. “Now this is a big range – which is exactly why we call it a risk: Science needs to be clear about the uncertainty, so that decision makers at the coast and in coastal megacities like Shanghai or New York can consider the potential implications in their planning processes,” says Levermann.

The scientists analyzed how rising global mean temperatures resulted in a warming of the ocean around Antarctica, thus influencing the melting of the Antarctic ice shelves. The marine ice sheets in West Antarctica alone have the potential to elevate sea level by several meters – over several centuries. Continue reading

Antarctica’s Thwaites Glacier starting to collapse

d

Thwaites Glacier, Photo courtesy NASA.

New data means sea level may rise more — and sooner — than expected

Staff Report

FRISCO — Antarctica’s massive, fast-moving Thwaites Glacier is probably going to be history in a couple of centuries, leading to a two-foot rise in global sea level, according to a new study funded by the National Science Foundation.

The glacier is a key piece in the global sea level puzzle, acting as an ice dam, stabilizing and regulating movement toward the sea of the massive West Antarctic Ice Sheet. The ice sheet contains enough ice to cause another 3 to 4 meters (10 to 13 feet) of global sea level rise. Continue reading

Climate: West Antarctic Ice Sheet is in trouble

Meltdown is inevitable …

eg

New findings require upward revision of sea level rise estimates. bberwyn photo.

By Summit Voice

FRISCO — Scientists say it’s only a matter of time before a huge chunk of the West Antarctic Ice Sheet melts into the ocean, potentially raising sea level around the world by several feet.

“The collapse of this sector of West Antarctica appears to be unstoppable,” said glaciologist Eric Rignot, a UC Irvine Earth system science professor who is also with NASA’s Jet Propulsion Laboratory. “The fact that the retreat is happening simultaneously over a large sector suggests it was triggered by a common cause, such as an increase in the amount of ocean heat beneath the floating parts of the glaciers. At this point, the end appears to be inevitable.” Continue reading

UK scientists seek to pinpoint West Antarctic ice loss

Robots, seal-mounted instruments and remote-operated subs part of ambitious project to study Pine Island, Thaite glaciers

West Antarctic ice sheets

West Antarctic ice sheets are melting fast, and scientists want to know why. bberwyn photo

By Summit Voice

FRISCO — With this year’s Antarctic research season starting to ramp up, a key focus is taking a closer look at ice sheets on the western side of the continent, where rapid ice loss from the Pine Island and Thwaite glaciers could affect sea level worldwide.

A team of researchers led by the British Antarctic Survey aims to discover what’s causing the recent rapid ice loss, and whether this loss will continue to increase or slow down. Continue reading

Climate: Does El Niño drive West Antarctic warming?

Ice cores suggest current climate is in the natural range of variability

fghj

Climate scientists track Antarctic changes, Bob Berwyn photo.

By Summit Voice

FRISCO — Ice cores from West Antarctica spanning the last 2,000 years suggest that recent warming and glacier loss in the region is comparable to other warm periods during that span.

Most of the recent warming may be related to powerful El Niño phases in the tropical Pacific in the 1990s, said University of Washington researcher Eric Steig. The ice core record shows similar temperature spikes in the 1830s and 1940s, he said, adding that the recent warming  cannot be attributed with confidence to human-caused global warming.

Steig built on previous research showing that rapid thinning of Antarctic glaciers was accompanied by rapid warming and changes in atmospheric circulation near the coast. The new study suggests that the 1990s were not all that different from some of those earlier warm spells. Continue reading

New ice core data from Greenland offers chilling clues about the direction of Earth’s climate

‘Our kids and grandkids are definitely going to look back and shake their heads at the inaction of this country’s generation’

dfg

For several days in July 2012, the surface of the Greenland ice sheet melted over a larger area than at any time in more than 30 years of satellite observations. An estimated 97 percent of the ice sheet surface had thawed by July 12, with satellite data providing a picture of an extreme melt event about which scientists are very confident. Graphic courtest Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth Observatory.

By Summit Voice

FRISCO — Last summer’s unusual melting at the surface of Greenland’s ice cap has a historic precedent, but you have to go back more than 100,000 years, to an extremely warm interglacial period of Earth’s history, to find it, according to an international science team’s  analysis of ice core samples spanning millennia of climate history.

The new study, published this week in Nature, offers clues about where the planet is headed in terms of increasing greenhouse gases and rising temperatures, according to CU-Boulder ice core expert Jim White — another researcher whose detailed knowledge of climate science has led him to advocate for reductions in greenhouse gas emissions.

“Unfortunately, we have reached a point where there is so much carbon dioxide in the atmosphere it’s going to be difficult for us to further limit our impact on the planet,” White said. “Our kids and grandkids are definitely going to look back and shake their heads at the inaction of this country’s generation. We are burning the lion’s share of oil and natural gas to benefit our lifestyle, and punting the responsibility for it.” Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,475 other followers