0CFE69074D054EC786164AC7D52B6357
USA

WeatherBug® Your Weather Just Got Better™

Change Units: °F  | °C

Weather News

USA

An Unexpected Lesson in Antarctic Ice Melt

June 15, 2013

By The Los Angeles Times

Enlarge

It`s called calving, and it occurs when enormous chunks of ice burst free from glaciers or floating ice shelves and drop into the sea with an explosive, heart-stopping crash.

This process, which produces icebergs, has long been viewed as the primary mechanism for ice loss along the continent of Antarctica.

Now however, scientists say calving is only half the story.

In what is being described as the first comprehensive survey of all Antarctic ice shelves, a study published Friday in the journal Science reports that 55% of the ice loss is due to melting at the base of these vast ice sheets.

"We find that iceberg calving is not the dominant process of ice removal," wrote Eric Rignot, a professor of earth system science at UC Irvine. "Ice shelves melt mostly from the bottom before they even form icebergs."

Ice shelves are permanent sheets of floating ice that cling to land masses. They are found mostly in the Antarctic.

The study`s conclusions were based on ice thickness data collected by NASA`s Operation Ice Bridge, a six-year program that uses satellites, aircraft, radio echo sounding and other means to survey ice cover on both of Earth`s poles.

Researchers found that basal melting in Antarctic ice shelves accounted for roughly 1,325 gigatons of melted ice per year, while calving accounted for 1,089 gigatons.

That melting however does not translate to a direct loss of Antarctic ice. Many ice shelves are near equilibrium, the authors wrote. Others were gaining more ice while others were losing overall ice.

Due to a number of factors, including geography and wind patterns, the North and South poles are experiencing opposite trends in sea ice.

The extent of summer sea ice in the Arctic has declined significantly over the last 30 years, while sea ice cover has been growing in Antarctica. However, the growth of sea ice in the south has not been as large as the loss of sea ice in the north.

---

Copyright Los Angeles Times 2013

---

Story image: In this file photo provided by Aurora Expeditions, an inflatable boat carries tourists past an iceberg along the Antarctic Peninsula. AP Photo/Aurora Expeditions, Andrew Halsall

What do you think of this story?
Click here for comments or suggestions.

Recent Stories:

News submitted by WeatherBug users

Backyard Blog

News, observations and weather commentary

Photo Gallery

View images of recent storms and seasonal weather.

User Videos

WeatherBug community news and weather videos.

Weather Groups

Discuss severe weather and regional storm activity.

Featured Cameras

Live Camera from a random camera within the United States
View live images and time-lapse video animation from local WeatherBug weather cameras.

WeatherBug Featured Content

Green Living

Green Living

You too can help save our planet and put money back in your wallet. Learn how you can take the first steps to reduce your environmental impact, including driving green, easy ways you can conserve water, and energy saving tips. To learn more and discover the benefits of going green, visit WeatherBug’s green living section. More >

Sponsored Content