News / Science & Technology

Study Links Arctic Melting, Extreme Weather

FILE - The Arctic ice cap.
FILE - The Arctic ice cap.
As ice at the North Pole disappears at an alarming rate, researchers are finding a link with recent bouts of extreme weather.

A new study suggests rapid warming in the Arctic may be altering weather patterns across the Northern Hemisphere.

But skeptics say the case is far from proven.

An “unbelievable amount of change” is happening in the Arctic, says Rutgers University climate scientist Jennifer Francis. Just half as much area is covered by ice compared to 30 years ago.

“And if you take into account the thickness as well, we’ve lost almost three-quarters of the volume of the sea ice,” she said.

Melting ice, heat waves

At the same time, the Northern Hemisphere has seen some unbelievable weather in the last decade: Record-breaking heat waves and droughts in North America and Europe, and devastating floods in East Asia, to name a few.

Francis and colleagues went back through three decades of weather data and measurements of Arctic ice and snow cover in northern latitudes. They found that, “when there was less ice or less snow in any given year during the summertime, that that was more likely to occur at the same time as the occurrences of heat waves,” she says.

They published their findings in Nature Climate Change. 

Weaker jet stream

Francis says the loss of ice and snow are affecting the high-altitude wind patterns called the jet stream, which push weather patterns around the Northern Hemisphere.

The jet stream is driven by the difference in temperature between the Arctic and the temperate zones. The bigger the difference, the faster the jet stream flows.

But Francis notes that the Arctic is warming at least twice as fast as the rest of the planet.

“If we warm the arctic faster,” she said, “it’s decreasing the temperature difference and causing the jet stream to get weaker.”

Weaker and wavier

And a weaker jet stream is wavier, she says. Think of a stream flowing down a mountain. The steeper the height difference, the faster and straighter it runs. On level ground, that stream can meander.

As the jet stream meanders, Francis adds, it pulls hot weather up from the tropics or cold weather down from the Arctic.

“As these waves get larger, they tend to move more slowly from west to east. So, whatever weather they’re causing down at the surface also changes more slowly.”

And that means heat waves, cold snaps and rainstorms can last longer.

Unproven link

This theory has only been around for a couple years, and University of Exeter climate scientist James Screen is one of those who are not convinced.

Screen says the new study only shows a few scattered areas of the globe where the link between sea ice loss and heat waves is significant, according to mathematical tests, “which implies either that the relationship is quite weak, or actually, it could be interpreted that the relationship doesn’t exist at all.”

“It could be true,” he said, “but at the moment I don’t think the evidence is there to really strongly argue the case.”

National Oceanic and Atmospheric Administration climate researcher James Overland says he’s “pretty much in the middle ground on how proven it is.” But, he adds, “certainly something’s going on that needs a closer look.”

Overland wrote a commentary accompanying the article. In it, he says better understanding of how the changing Arctic affects global weather could help improve forecasting.

That’s increasingly important, he notes, because global greenhouse gas emissions will continue to melt the Arctic for decades to come.

“The loss of sea ice will go from 50 percent to 100 percent in the next 20 years or so,” he said. “We’re just going to have a whole lot more fuel for the atmosphere to use up."

And one way or another, he says, "it’ll end up with the increased chance of more of these extreme events down here where people live.”

You May Like

Lesotho Faces New Round of Violence, Political Crisis

Brutal killing of military officer has sent former leaders back into S. Africa where they're watching anxiously as regional officials head in to try to restore peace More

Video US Diplomat Expects Adoption of Bosnian Massacre Anniversary Resolution

Samantha Power says there's broad consensus about killings in Bosnia's war, but Russia calls resolution 'divisive,' backs UN countermeasure More

UN Report Exposes Widespread Boko Haram Atrocities

Damning report graphically details pattern of vicious, widespread atrocities committed by Islamist militants More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Olympics Construction Scars Sacred Korean Mountaini
X
July 02, 2015 4:10 AM
Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Olympics Construction Scars Sacred Korean Mountain

Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Xenophobia Victims in South Africa Flee Violence, Then Return

Many Malawians fled South Africa early this year after xenophobic attacks on African immigrants. But many quickly found life was no better at home and have returned to South Africa – often illegally and without jobs, and facing the tough task of having to start over. Lameck Masina and Anita Powell file from Johannesburg.
Video

Video Family of American Marine Calls for Release From Iranian Prison

As the crowd of journalists covering the Iran talks swells, so too do the opportunities for media coverage.  Hoping to catch the attention of high-level diplomats, the family of American-Iranian marine Amir Hekmati is in Vienna, pleading for his release from an Iranian prison after nearly 4 years.  VOA’s Heather Murdock reports from Vienna.
Video

Video UK Holds Terror Drill as MPs Mull Tunisia Response

After pledging a tough response to last Friday’s terror attack in Tunisia, which came just days before the 10th anniversary of the bomb attacks on London’s transport network, British security services are shifting their focus to overseas counter-terror operations. VOA's Henry Ridgwell has more.
Video

Video Obama on Cuba: This is What Change Looks Like

President Barack Obama says the United States will soon reopen its embassy in Cuba for the first time since 1961, ending a half-century of isolation. VOA White House correspondent Luis Ramirez reports.
Video

Video Hate Groups Spread Influence Via Internet

Hate groups of various kinds are using the Internet for propaganda and recruitment, and a Jewish human rights organization that monitors these groups, the Simon Wiesenthal Center, says their influence is growing. The messages are different, but the calls to hatred or violence are similar. VOA's Mike O’Sullivan reports.
Video

Video US Silica Sand Mining Surge Worries Illinois Residents, Businesses

Increased domestic U.S. oil and gas production, thanks to advances known as “fracking,” has created a boom for other industries supporting that extraction. Demand for silica sand, used in fracking, could triple over the next five years. In the Midwest state of Illinois, people living near the mines are worried about how increased silica sand mining will affect their businesses and their health. VOA’s Kane Farabaugh has more in this first of a series of reports.
Video

Video Blind Somali Journalist Defies Odds in Mogadishu

Despite improving security in the last few years, Somalia remains one of the most dangerous countries to be a journalist – even more so for someone who cannot see. Abdulaziz Billow has the story of journalist Abdifatah Hassan Kalgacal, who has been reporting from the Somali capital for the last decade despite being blind.
Video

Video Texas Defies Same-Sex Marriage Ruling

Texas state officials have criticized the US Supreme Court decision giving same-sex couples the right to marry nationwide. The attorney general of Texas says last week's decision did not overrule constitutional "rights of religious liberty," and therefore officials performing wedding services can refuse to perform them for same-sex couples if it is against their religious beliefs. Zlatica Hoke reports on the controversy.
Video

Video Rabbi Hits Road to Heal Jewish-Muslim Relations in France

France is on high alert after last week's terrorist attack near the city Lyon, just six months after deadly Paris shootings. The attack have added new tensions to relations between French Jews and Muslims. France’s Jewish and Muslim communities also share a common heritage, though, and as far as one French rabbi is concerned, they are destined to be friends. From the Paris suburb of La Courneuve, Lisa Bryant reports about Rabbi Michel Serfaty and his friendship bus.
Video

Video Saudi Leaks Expose ‘Checkbook Diplomacy’ In Battle With Iran

Saudi Arabia’s willingness to wield its oil money on the global diplomatic stage appears to have been laid bare, after the website WikiLeaks published tens of thousands of leaked cables from Riyadh’s Ministry of Foreign Affairs. VOA's Henry Ridgwell reports.
Video

Video In Kenya, Police Said to Shoot First, Ask Questions Later

An organization that documents torture and extrajudicial killings says Kenyan police were responsible for 1,252 shooting deaths in five cities, including Nairobi, between 2009 and 2014, representing 67 percent of all gun deaths in the areas reviewed. Gabe Joselow has more from Nairobi.

VOA Blogs