News / Science & Technology

Study: Greenland Ice Less Vulnerable Than Feared to Thaw

Icebergs are reflected in the calm waters at the mouth of the Jakobshavn ice fjord near Ilulissat in Greenland. (file photo)
Icebergs are reflected in the calm waters at the mouth of the Jakobshavn ice fjord near Ilulissat in Greenland. (file photo)
Reuters
Greenland is less vulnerable than expected to a runaway melt that would drive up world sea levels, according to scientists who found that only a quarter of the ice sheet thawed in a warm period more than 100,000 years ago.
    
The study, involving 300 experts from 14 nations, implied that Antarctica at the other end of the planet would contribute at least as much or more to the kind of sea level rise that threatens coasts and cities from Mumbai to Miami.
    
Climate scientists are struggling to understand the risks of a melt of the vast ice stores of Greenland and Antarctica to help plan coastal protection. Sea levels rose about 17 cm (7 inches) in the past century and the rate has quickened.
    
Examination of ice from a 2.5 km- (1.5 mile-) deep ice core in northwest Greenland indicated that its ice sheet lost only about 400 meters (1,300 ft) in thickness in the early part of the Eemian, a warm period from about 130,000 to 115,000 years ago.
    
They estimated it lost about a quarter of its ice overall, according to a study published in Thursday's edition of the journal Nature.

"The volume of ice lost from the Greenland ice sheet was more moderate than many had expected,'' lead author Dorthe Dahl-Jensen, a professor at the University of Copenhagen, told Reuters.
    
Some past studies have suggested that Greenland may be poised for an irreversible melt due to climate change, blamed by a U.N. panel of experts on use of fossil fuels in nations led by China, the United States, India and Russia.

The limited size of the melt was also a surprise because the scientists found that Eemian temperatures, inferred from chemicals in air bubbles trapped in the ice, were higher than expected at 8 degrees Celsius (14 Fahrenheit) above current levels.
    
Fossil fuels

"We'll probably reach the Eemian temperatures within the next 100 years,'' Dahl-Jensen said. The Arctic region is warming at one of the fastest rates on the planet; global warming of 2 or 3 degrees Celsius (3.6 to 5.4 F) might trigger an 8 degrees C rise in Greenland.
    
The United Nations panel of climate scientists has said that sea levels may rise by between 18 and 59 cm (7-24 inches) this century, or by more if a thaw of Greenland or Antarctica speeds up. Elsewhere, it expects more floods, droughts and heatwaves.
    
And there are already signs of Eemian-style conditions. In July 2012, almost the entire surface of Greenland was covered in melt water, an event witnessed by the scientists from the United States, Canada, France, Germany, Britain, Japan, South Korea and elsewhere.

"It even rained in our camp,'' Dahl-Jensen said.

Ice cores build up from annual snowfall and can be read like tree rings to judge their age. The Eemian warmth was probably caused by natural shifts in the Earth's orbit around the sun.

The scientists estimated that Greenland contributed only about 2 meters to sea level rise of between 4 and 8 meters during the Eemian.
    
That meant that at least half and perhaps much more of the melt water came from Antarctica, the planet's other big store of land ice, which, unlike the floating ice of the Arctic, causes the sea level to rise when it melts.
    
As yet, there has been no study of cores from the crucial West Antarctic ice sheet equivalent to the Greenland research.

You May Like

Changing Under Pressure, IS ‘Potent’ as Ever

US intel officials describe Ramadi's fall as concerning, but say it isn't emblematic of larger effort to degrade IS capabilities More

Nigeria Fuel Shortage Shows Fragility of Africa’s Oil Giant

Although it is the largest oil producer in Africa, country has nearly ran out of fuel it needs to power its generators, cars and airplanes over the past week More

Arrested Football Officials Come Mainly From the Americas

US Justice Department alleges defendants participated in 24-year scheme to enrich themselves through corruption of international soccer More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
3D Printer Makes Replica of Iconic Sports Cari
|| 0:00:00
...    
🔇
X
George Putic
May 27, 2015 9:31 PM
Cars with parts made by 3D printers are already on the road, but engineers are still learning about this new technology. While testing the possibility of printing an entire car, researchers at the U.S. Department of Energy recently created an electric-powered replica of an iconic sports roadster. VOA’s George Putic has more.
Video

Video 3D Printer Makes Replica of Iconic Sports Car

Cars with parts made by 3D printers are already on the road, but engineers are still learning about this new technology. While testing the possibility of printing an entire car, researchers at the U.S. Department of Energy recently created an electric-powered replica of an iconic sports roadster. VOA’s George Putic has more.
Video

Video US Voters Seek Answers From Presidential Candidates on IS Gains

The growth of the Islamic State militant group in Iraq and Syria comes as the 2016 U.S. presidential campaign kicks off in the Midwest state of Iowa.   As VOA’s Kane Farabaugh reports, voters want to know how the candidates would handle recent militant gains in the Middle East.
Video

Video A Small Oasis on Kabul's Outskirts Provides Relief From Security Tensions

When people in Kabul want to get away from the city and relax, many choose Qargha Lake, a small resort on the outskirts of Kabul. Ayesha Tanzeem visited and talked with people about the precious oasis.
Video

Video Film Festival Looks at Indigenous Peoples, Culture Conflict

A recent Los Angeles film festival highlighted the plight of people caught between two cultures. Mike O'Sullivan has more on the the Garifuna International Film Festival, a Los Angeles forum created by a woman from Central America who wants the world to know more about her culture.
Video

Video Kenyans Lament Losing Sons to al-Shabab

There is agony, fear and lost hope in the Kenyan town of Isiolo, a key target of a new al-Shabab recruitment drive. VOA's Mohammed Yusuf visits Isiolo to speak with families and at least one man who says he was a recruiter.
Video

Video Scientists Say Plankton More Important Than Previously Thought

Tiny ocean creatures called plankton are mostly thought of as food for whales and other large marine animals, but a four-year global study discovered, among other things, that plankton are a major source of oxygen on our planet. VOA’s George Putic reports.
Video

Video US-led Coalition Gives Some Weapons to Iraqi Troops

In a video released Tuesday from the Iraqi Ministry of Defense, Iraqi forces and U.S.-led coalition troops survey a cache of weapons supplied to help Iraq liberate Mosul from Islamic State group. According to a statement provided with the video, the ministry and the U.S.-led coaltion troops have started ''supplying the 16th army division with medium and light weapons in preparation to liberate Mosul and nearby areas from Da'esh (Arabic acronym for Islamic State group).''
Video

Video Amnesty International: 'Overwhelming Evidence' of War Crimes in Ukraine

Human rights group Amnesty International says there is overwhelming evidence of ongoing war crimes in Ukraine, despite a tentative cease-fire with pro-Russian rebels. Researchers interviewed more than 30 prisoners from both sides of the conflict and all but one said they were tortured. Henry Ridgwell reports for VOA from London.
Video

Video Washington Parade Honors Those Killed Serving in US Military

Every year, on the last Monday in the month of May, millions of Americans honor the memories of those killed while serving in the armed forces. Memorial Day is a tradition that dates back to the 19th Century. While many people celebrate the federal holiday with a barbecue and a day off from work, for those who’ve served in the military, it’s a special day to remember those who made the ultimate sacrifice. Arash Arabasadi reports for VOA from Washington.
Video

Video Kenya’s Capital Sees Rise in Shisha Parlors

In Kenya, the smoking of shisha, a type of flavored tobacco, is the latest craze. Patrons are flocking to shisha parlors to smoke and socialize. But the practice can be addictive and harmful, though many dabblers may not realize the dangers, according to a new review. Lenny Ruvaga has more on the story for VOA from Nairobi, Kenya.
Video

Video Rolling Thunder Run Reveals Changed Attitudes Towards Vietnam War

For many US war veterans, the Memorial Day holiday is an opportunity to look back at a divisive conflict in the nation’s history and to remember those who did not make it home.
Video

Video Female American Soldiers: Healing Through Filmmaking

According to the United States Defense Department, there are more than 200-thousand women serving in the U.S. Armed Forces.  Like their male counterparts, females have experiences that can be very traumatic.  VOA's Bernard Shusman tells us about a program that is helping some American women in the military heal through filmmaking.

VOA Blogs