News / Science & Technology

Warming Oceans Cause Bulk of Antarctic Ice Loss

This photo shows the ice front of Venable Ice Shelf, West Antarctica, in October 2008. (NASA/JPL-Caltech/UC Irvine)
This photo shows the ice front of Venable Ice Shelf, West Antarctica, in October 2008. (NASA/JPL-Caltech/UC Irvine)

Related Articles

Scientists Reconstruct 2,000 Years of Temperature Change

New study says world-wide warming trend began at end of 19th century and that past 30 years warmest in 1,400 years

Japanese Researchers Find Possible Lost Continent in Atlantic Ocean

Granite found on seabed, suggesting a continent may have once existed off coast of Brazil
Most of the loss Antarctic ice is not caused by icebergs falling apart into the sea, but instead by warmer ocean waters underneath the massive ice shelves causing melting, according to a new study by NASA and university researchers.

The study found that so-called basal melt accounted for 55 percent of all ice shelf mass loss from 2003 to 2008.  Using reconstructions of ice accumulation as well as satellite and aircraft readings of ice thickness and changes in elevations, scientists were able to compare the speed of ice shelf melt versus that of calving, or the splitting of icebergs.

"The traditional view on Antarctic mass loss is it is almost entirely controlled by iceberg calving," said Eric Rignot of NASA's Jet Propulsion Laboratory in Pasadena, Calif.

"Our study shows melting from below by the ocean waters is larger, and this should change our perspective on the evolution of the ice sheet in a warming climate," said Rignot, lead author of the study to be published in the June 14 issue of the journal Science.

According to NASA, the Antarctic ice shelves lost 1,325 trillion kilograms of ice per year in 2003 to 2008 through basal melt, while calving accounted for 1,089 trillion kilograms of mass loss each year.

Rates of basal melt of Antarctic ice shelves (melting of the shelves from underneath) overlaid on a 2009 mosaic of Antarctica created from data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra and Aqua spaceRates of basal melt of Antarctic ice shelves (melting of the shelves from underneath) overlaid on a 2009 mosaic of Antarctica created from data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra and Aqua space
x
Rates of basal melt of Antarctic ice shelves (melting of the shelves from underneath) overlaid on a 2009 mosaic of Antarctica created from data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra and Aqua space
Rates of basal melt of Antarctic ice shelves (melting of the shelves from underneath) overlaid on a 2009 mosaic of Antarctica created from data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA's Terra and Aqua space
Determining how the ice is melting will help scientists improve models on how the Antarctic ice sheet will evolve with warming ocean temperatures, including how it could contribute to sea level rise and changing ocean circulation.

"Changes in basal melting are helping to change the properties of Antarctic bottom water, which is one component of the ocean's overturning circulation," said another study author, Stan Jacobs, an oceanographer at Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York. "In some areas it also impacts ecosystems by driving coastal upwelling, which brings up micronutrients like iron that fuel persistent plankton blooms in the summer."

The rate of basal melting varies around the continent. The three giant ice shelves - Ross, Filchner and Ronne, which make up two-thirds of the total Antarctic ice shelf area - accounted for only 15 percent of basal melting. Smaller ice shelves produced half of the basal melt over the period studied, NASA said.

"Ice shelf melt doesn't necessarily mean an ice shelf is decaying. It can be compensated by the ice flow from the continent," Rignot said. "But in a number of places around Antarctica, ice shelves are melting too fast, and a consequence of that is glaciers, and the entire continent, are changing as well."

You May Like

Photogallery Pistorius Sentenced, Taken to Prison

Pistorius, convicted of culpable homicide in shooting death of girlfriend Reeva Steenkamp, will likely serve about 10 months of five-year sentence, before completing it under house arrest More

UN to Aid Central Africa in Polio Vaccinations

Synchronized vaccinations will be conducted after Cameroon reports a fifth case of the wild polio virus in its territory More

WHO: Ebola Vaccine May Be in Use by Jan.

WHO assistant director Dr. Marie Paule Kieny says clinical trials of Ebola vaccines are underway or planned in Europe, US and Africa More

This forum has been closed.
Comment Sorting
Comments
     
by: Roger Halstead from: Midland MI
June 21, 2013 12:03 AM
So where does the added heat come from to melt this ice? It takes 100 calories to melt 1 cc of ice while that same calorie will warm 1 cc of water 1 degree. Melting ice: Natures air conditioner!


by: Kitagawa Keikoh from: Daikanyama, JPN
June 14, 2013 7:56 PM
What's wrong with climate change and melting ice?
It is one of the natural phenomena.
All we have to do is adjusting our life to current climate. We are not able to change our climate, and that means reducing CO2 has nothing with climate change.

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
After Decades of Pressure, Luxembourg Drops Bank Secrecy Rulesi
X
October 21, 2014 12:20 AM
European Union finance ministers have reached a breakthrough agreement that will make it more difficult for tax cheats to hide their money. The new legislation, which had been blocked for years by countries with a reputation as tax havens, was approved last week after Luxembourg and Austria agreed to lift their vetoes. But as Mil Arcega reports, it doesn’t mean tax cheats have run out of places to keep their money hidden.
Video

Video After Decades of Pressure, Luxembourg Drops Bank Secrecy Rules

European Union finance ministers have reached a breakthrough agreement that will make it more difficult for tax cheats to hide their money. The new legislation, which had been blocked for years by countries with a reputation as tax havens, was approved last week after Luxembourg and Austria agreed to lift their vetoes. But as Mil Arcega reports, it doesn’t mean tax cheats have run out of places to keep their money hidden.
Video

Video Kobani Refugees Welcome, Turkey Criticizes, US Airdrop

Residents of Kobani in northern Syria have welcomed the airdrop of weapons, ammunition and medicine to Kurdish militia who are resisting the seizure of their city by Islamic State militants. The Turkish government, however, has criticized the operation. VOA’s Scott Bobb reports from southeastern Turkey, across the border from Kobani.
Video

Video China Political Meeting Seeks to Improve Rule of Law

China’s communist leaders will host a top level political meeting this week, called the Fourth Plenum, and for the first time in the party’s history, rule of law will be a key item on the agenda. Analysts and Chinese media reports say the meetings could see the approval of long-awaited measures aimed at giving courts more independence and include steps to enhance an already aggressive and high-reaching anti-corruption drive. VOA’s Bill Ide has more from Beijing.
Video

Video US ‘Death Cafes’ Put Focus on the Finale

In contemporary America, death usually is a topic to be avoided. But the growing “death café” movement encourages people to discuss their fears and desires about their final moments. VOA’s Jerome Socolovsky reports.
Video

Video Ebola Orphanage Opens in Sierra Leone

Sierra Leone's first Ebola orphanage has opened in the Kailahun district. Hundreds of children orphaned since the beginning of the Ebola outbreak face stigma and rejection with nobody to care for them. Adam Bailes reports for VOA about a new interim care center that's aimed at helping the growing number of children affected by Ebola.
Video

Video Young Nairobi Tech Innovator on 'Track' in Security Business

A 24-year-old technology innovator in Nairobi has invented a tracking device that monitors and secures cars. He has also come up with what he claims is the most robust audio-visual surveillance system yet. As Lenny Ruvaga reports from the Kenyan capital, his innovations are offering alternative security solutions.
Video

Video Latinas Converting to Islam for Identity, Structure

Latinos are one of the fastest growing groups in the Muslim religion. According to the Pew Research Center, about 6 percent of American Muslims are Latino. And a little more than half of new converts are female. VOA’s Carolyn Presutti travelled to Miami, Florida -- where two out of every three residents is Hispanic -- to learn more.
Video

Video Exclusive: American Joins Kurds' Anti-IS Fight

The United States and other Western nations have expressed alarm about their citizens joining Islamic State forces in Syria and Iraq. In a rare counterpoint to the phenomenon, an American has taken up arms with the militants' Syrian Kurdish opponents. Elizabeth Arrott has more in this exclusive profile by VOA Kurdish reporter Zana Omer in Ras al Ayn, Syria.
Video

Video South Korea Confronts Violence Within Military Ranks

Every able-bodied South Korean male between 18 and 35 must serve for 21 to 36 months in the country’s armed forces, depending upon the specific branch. For many, service is a rite of passage to manhood. But there are growing concerns that bullying and violence come along with the tradition. Reporter Jason Strother has more from Seoul.
Video

Video North Carolina Emerges as Key Election Battleground

U.S. congressional midterm elections will be held on November 4th and most political analysts give Republicans an excellent chance to win a majority in the U.S. Senate, which Democrats now control. So what are the issues driving voters in this congressional election year? VOA National Correspondent Jim Malone traveled to North Carolina, one of the most politically competitive states in the country, to find out.
Video

Video Comanche People Maintain Pride in Their Heritage

The Comanche (Indian nation) once were called the “Lords of the Plains,” with an empire that included half the land area of current day Texas, large parts of Oklahoma, New Mexico, Kansas and Colorado.The fierceness and battle prowess of these warriors on horseback delayed the settlement of most of West Texas for four decades. VOA’s Greg Flakus reports from Lawton, Oklahoma, that while their warrior days are over, the 15,000 members of the Comanche Nation remain a proud people.
Video

Video Turkey Campus Attacks Raise Islamic Radicalization Fears

Concerns are growing in Turkey of Islamic radicalization at some universities, after clashes between supporters of the jihadist group Islamic State (IS) or ISIS, and those opposed to the extremists. Pro-jihadist literature is on sale openly on the streets of Istanbul. Critics accuse the government of turning a blind eye to radicalism at home, while Kurds accuse the president of supporting IS - a charge strongly denied. Henry Ridgwell reports from London.

All About America

AppleAndroid