Global glacier index

February 9, 2009

in Science, The environment

Tristan Laing in my living room

This winter has involved a lot of debate on climate changed based around anecdotes: ‘it is snowing in England, therefore it isn’t happening’ or ‘there are terrible fires in Austalia so it is.’ In the end, while anecdotes can provide the imagery that motivates people to act, it is only through the analysis of large amounts of data that high quality conclusions can be reached.

On that front, the global glacier index update on RealClimate is a good example. They examine data on the mass balances of glaciers around the world between 1980 and present, revealing a very clear trend. Similar statistical analysis is performed on the terminus behaviour of the glaciers.

Human beings have a tendency to place undue weight on things we happened to personally observe recently. It’s part of a set of heuristics that aids our functioning in some circumstances, but it does us a great disservice when we are contemplating phenomena that are exterior to our normal modes of operation.

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{ 11 comments… read them below or add one }

. February 9, 2009 at 10:05 am

Al Gore added a new satellite photograph to his now-famous slide show when he showed it to U.S. senators on Wednesday.

It showed that the glaciers of the Himalayas, the primary source of fresh water for much of southern and central Asia, are shrinking.

Gore rattled off the names of the great rivers that carry Himalayan snowmelt to the teeming populations of China, Pakistan, India and other parts of southeast Asia, and to the farmlands that feed them.

“When the glaciers disappear, the source of the water will disappear,” Gore told the Senate Foreign Relations Committee.

Litty February 9, 2009 at 8:23 pm

Very intense gaze in this photo!

Claire February 11, 2009 at 5:33 am

Also, my (albeit v limited) understanding of climate change is that it involves some places experiencing more severe, sometimes colder or wetter, weather too. The snow in England was a freak event in many ways, and, accepting your warning about reading too much into isolated incidents, could provide as much anaecdotal evidence of things getting weird as the wildfires in Australia.

In the UK we certaintly seem to be breaking weather records every other month lately (wettest summer on record, hottest day, thickest snow for 20 years etc etc). Should we read anything into this, or are there so many permutations and measurements of weather that it’s very easy to make superlative claims?

Milan February 11, 2009 at 9:00 am

Claire,

It is a tricky balancing act, to both acknowledge that climate change will certainly produce some weird and extreme events, while also recognizing that the attribution of particular events to climate change is problematic, at best.

Climate change will definitely alter precipitation patterns. In some areas, that will mean more snow (though possibly at higher normal winter temperatures than existed beforehand).

Right now, a huge amount of effort is being dedicated to ‘downscaled’ global climate models so as to be able to provide more precise estimates of the effects of different degrees of warming in different areas.

On a partial side note, the British Met Office is quite an impressive organization, both on account of its scientific output and its willingness to make the implications of it publicly comprehensible.

. February 25, 2009 at 3:17 pm

Antarctic glaciers slipping swiftly seaward: study

ELIANE ENGELER

The Associated Press

February 25, 2009 at 8:59 AM EST

Geneva — Antarctic glaciers are melting faster across a much wider area than previously thought, scientists said Wednesday — a development that could lead to an unprecedented rise in sea levels.

A report by thousands of scientists for the 2007-2008 International Polar Year concluded that the western part of the continent is warming up, not just the Antarctic Peninsula.

Previously most of the warming was thought to occur on the narrow stretch pointing toward South America, said Colin Summerhayes, executive director of the Britain-based Scientific Committee on Antarctic Research and a member of International Polar Year’s steering committee.

. May 8, 2009 at 9:38 pm

Another one bites the dust, literally: Bolivia’s 18,000 year-old Chacaltaya glacier is gone

Like the Wicked Witch of the West, the world is melting — and fast.

The University of Zurich’s World Glacier Monitoring Service reported earlier this year, “The new data continues the global trend in accelerated ice loss over the past few decades.” The rate of ice loss is twice as fast as a decade ago. “The main thing that we can do to stop this is reduce greenhouse gases” said Michael Zemp, a researcher at the University of Zurich’s Department of Geography.

. May 14, 2009 at 11:27 am

Huge Bolivian glacier disappears

Scientists in Bolivia say that one of the country’s most famous glaciers has almost disappeared as a result of climate change.

The Chacaltaya glacier, 5,300m (17,400 ft) up in the Andes, used to be the world’s highest ski run.

But it has been reduced to just a few small pieces of ice.

Many Bolivians on the highland plains, and in two cities, depend on the melting of the glaciers for their water supply during the dry season.

. September 24, 2009 at 1:32 pm

Laser satellite records ice loss
By Jonathan Amos
Science reporter, BBC News

Greenland and parts of Antarctica are losing large volumes of ice to the oceans as their glaciers get thinner, a Nasa satellite has revealed.

Many glaciers have increased their flow rates in recent years, and the Icesat mission now allows scientists to measure their thickness in detail.

A UK team studying the data told the journal Nature that the findings had implications for future sea-level rise.

A full melt of the Greenland ice would push sea level up by about 7m (20ft).

The extent of “dynamic thinning”, observed by the satellite, has been a major source of uncertainty in projections of sea-level rise.

“All of the glaciers that are changing rapidly are ones that flow into the sea,” said Hamish Pritchard from the British Antarctic Survey (BAS).

“The fact that they end in the sea means a buoyancy effect is working on them,” he told BBC News.

“Normally, they’re heavy things and they rest on the sea-bed and friction slows them down. But as you start to thin glaciers, they start to float off the sea-bed more and more; there’s less friction and the glaciers can speed up.”

. October 2, 2009 at 10:52 am

TED: James Balog: Time-lapse proof of extreme ice loss
Posted: Sep 2009

For several years, Balog has been going up north to shoot the half-alive ice of the mammoth glaciers for his Extreme Ice Survey, a look at the shocking effects of abrupt climate change in Alaska, Greenland and Iceland. Soaring, dripping, glowing and crumbling, arctic ice under Balog’s eye requires the viewer to engage.

. December 4, 2009 at 2:01 pm

Glacier threat to Bolivia capital

By David Shukman
Environment correspondent, BBC News, La Paz, Bolivia

Fears are growing for the future of water supplies in one of Latin America’s fastest-growing urban areas – Bolivia’s sprawling capital of La Paz and its twin El Alto.

Scientists monitoring the glaciers high in the Andes mountains – a key source of water – say the ice is showing signs of shrinking faster than previously forecast.

Faced with a booming population and a combination of glacial retreat and reduced rainfall, the governor of the La Paz region is even contemplating moving people to other parts of Bolivia.

Water is already in short supply among the poorest communities and has become a cause of tension.

. January 20, 2010 at 9:45 am

UN climate body admits ‘mistake’ on Himalayan glaciers

By Richard Black
Environment correspondent, BBC News website

The vice-chairman of the UN’s climate science panel has admitted it made a mistake in asserting that Himalayan glaciers could disappear by 2035.

The Intergovernmental Panel on Climate Change (IPCC) included the date in its 2007 assessment of climate impacts.

A number of scientists have recently disputed the 2035 figure, and Jean-Pascal van Ypersele told BBC News that it was an error and would be reviewed.

But he said it did not change the broad picture of man-made climate change.

The issue, which BBC News first reported on 05 December, has reverberated around climate websites in recent days.

The claim that Himalayan glaciers could disappear by 2035 appears to have originated in a 1999 interview with Indian glaciologist Syed Hasnain, published in New Scientist magazine.

The figure then surfaced in a 2005 report by environmental group WWF – a report that is cited in the IPCC’s 2007 assessment, known as AR4.

An alternative genesis lies in the misreading of a 1996 study that gave the date as 2350.

AR 4 asserted: “Glaciers in the Himalayas are receding faster than in any other part of the world… the likelihood of them disappearing by the year 2035 and perhaps sooner is very high.”

Dr van Ypersele said the episode meant that the panel’s reviewing procedures would have to be tightened.

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