Where Has All the Ice Gone?: Understanding Climate Change


| 3/18/2013 9:52:18 AM


Tags: glacier melt, glaciers, ice loss, climate change, global warming, Earth Policy Institute,

This article was reposted with permission from Earth Policy Institute.

As the earth warms, glaciers and ice sheets are melting and seas are rising. Over the last century, the global average sea level rose by 17 centimeters (7 inches). This century, as waters warm and ice continues to melt, seas are projected to rise nearly 2 meters (6 feet), inundating coastal cities worldwide, such as New York, London, and Cairo. Melting sea ice, ice sheets, and mountain glaciers are a clear sign of our changing climate. The historically ever-present white cap at the top of the globe could disappear entirely during the summer within two decades. 

In September 2012, sea ice in the Arctic Ocean shrank to a record low extent and volume. The region has warmed 2 degrees Celsius (3.6 degrees Fahrenheit) since the 1960s —twice as much as lower latitudes. With less snow and ice to reflect the sun’s rays and with more exposed ocean to absorb heat, a vicious cycle leads to even warmer temperatures. Thinner ice combined with rising temperatures makes it increasingly difficult for the sea ice to recover. The historically ever-present white cap at the top of the globe could disappear entirely during the summer within two decades.

The Arctic plays a pivotal role in large-scale weather patterns. The stark contrast between cold air at the North Pole and warmer air in the temperate zone drives the jet stream over North America, Europe and Russia. As the Arctic continues to warm faster than the rest of the globe, this contrast diminishes. This can change the path of the jet stream and slow it down, leaving weather systems in the same place for a longer time. A rainy spell that sticks around can turn into flooding, while a sunny spell can turn into a drought.

Warming in the Arctic is particularly important because of its effects on Greenland’s enormous ice sheet. Greenland’s ice loss has accelerated from 51 billion tons per year in the 1990s to 263 billion tons per year today. In July 2012, an iceberg twice the size of the island of Manhattan calved off Petermann glacier in northwestern Greenland. This was the second large calving event off this glacier in just two years: the iceberg that broke away in August 2010 was twice as large.

While Greenland’s ice loss is astonishing, on the other side of the globe, parts of Antarctica’s vast ice sheet may be even less stable. The continent is flanked by 54 major ice shelves, which act as brakes slowing the movement of ice in land-based glaciers out to sea. Twenty of them show signs of thinning and weakening, which translates into accelerated ice loss. After the 3,250-square-kilometer Larsen B Ice Shelf collapsed in 2002, for instance, the glaciers it was bracing flowed up to eight times faster than before. The most dramatic thinning is in West Antarctica. Melting mountain glaciers contribute to sea level rise as well, but they are of more immediate concern because of their roles in the everyday lives of millions of people. 

tori
9/9/2013 8:03:04 AM

Mother Earth News needs to stop letting people state things on their site until their have looked at all sides.. This is the newest report from other scientist as of (9-7-13)..a short paragraph below and here's the link for the whole article. http://www.dailymail.co.uk/news/article-2415191/Global-cooling-Arctic-ice-caps-grows-60-global-warming-predictions.html The Northwest Passage from the Atlantic to the Pacific has remained blocked by pack-ice all year. More than 20 yachts that had planned to sail it have been left ice-bound and a cruise ship attempting the route was forced to turn back. Some eminent scientists now believe the world is heading for a period of cooling that will not end until the middle of this century – a process that would expose computer forecasts of imminent catastrophic warming as dangerously misleading. The disclosure comes 11 months after The Mail on Sunday triggered intense political and scientific debate by revealing that global warming has ‘paused’ since the beginning of 1997 – an event that the computer models used by climate experts failed to predict. In March, this newspaper further revealed that temperatures are about to drop below the level that the models forecast with ‘90 per cent certainty’. The pause – which has now been accepted as real by every major climate research centre – is important, because the models’ predictions of ever-increasing global temperatures have made many of the world’s economies divert billions of pounds into ‘green’ measures to counter climate change Read more: http://www.dailymail.co.uk/news/article-2415191/Global-cooling-Arctic-ice-caps-grows-60-global-warming-predictions.html#ixzz2eOp63o00 Follow us: @MailOnline on Twitter | DailyMail on Facebook


upnorthmn
9/9/2013 7:46:33 AM

Between Aug 2012 to Aug 2013, record return of Arctic ice cap as it grows by 60% in a year. Just another article/propaganda from MEN.


deborahs
9/9/2013 7:44:02 AM

I think there has been a great deal of misinformation being put out on both sides of this issue, but if you go to http://www.dailymail.co.uk/news/article-2415191/Global-cooling-Arctic-ice-caps-grows-60-global-warming-predictions.html you can see the 60% increase of the ice field over the last year. It's an interesting article.


pettros
9/9/2013 7:38:04 AM

relax, I've got some good news - 60% more sea ice in the arctic this year than last year according to NASA satellite imagery. http://www.dailymail.co.uk/news/article-2415191/Global-cooling-Arctic-ice-caps-grows-60-global-warming-predictions.html


pettros
9/9/2013 7:28:54 AM

relax, I've got some good news - 60% more sea ice in the arctic this year than last year according to NASA satellite imagery. http://www.dailymail.co.uk/news/article-2415191/Global-cooling-Arctic-ice-caps-grows-60-global-warming-predictions.html





mother earth news fair

MOTHER EARTH NEWS FAIR

Feb. 17-18, 2018
Belton, Texas

More than 150 workshops, great deals from more than 200 exhibitors, off-stage demos, hands-on workshops, and great food!

LEARN MORE