Arctic Methane Emissions Underestimated

As Arctic temperatures rise, thawing permafrost is releasing greenhouse gases into the atmosphere. Scientists are concerned about the magnitude of these greenhouse gas emissions and how much they will drive future global warming.

Most studies of permafrost emissions have focused on their summertime behavior, but a new study finds that cold-season emissions should not be ignored, the Washington Post reports.

The researchers looked at the emissions of methane – a potent but short-lived greenhouse gas – from five sites in Alaska between June 2013 and January 2015. They found about half the methane emitted in a year was released between September and May.

Current climate models do not include methane emissions that occur during the cold season, assuming that they are negligible. The new research suggests that the models must be upgraded to make better predictions about how much methane the Arctic will release in the future.

“It is now time to work more closely with climate modelers and assure these observations are used to improve model predictions, and refine our prediction of the global methane budget,” Donatella Zona, an assistant professor at San Diego State University and research fellow at the University of Sheffield, said in a statement.

Parasites Expand Range in Warmer Arctic

Parasites that infect musk oxen and caribou have expanded northward as climate change has removed the temperature barriers that once contained them, the Calgary Herald reports.

In the 1990s, the two species of lungworm could only be found in the west central part of the Canadian Arctic. By 2000, they were on Victoria Island in Nunavut and they are now 200km (124 miles) further north. Lead author Susan Kutz, an associate professor at the University of Calgary’s faculty of veterinary medicine, told the Herald that the changing climate had allowed the lungworms to push northward and had played a role in the decline of the musk ox population. The infected animals may have trouble breathing and be easier for predators to hunt down.

CBC News reported in August that Kutz had identified a bacteria on deceased musk oxen on Banks Island in the Northwest Territories and on Victoria Island. Lemmings may have transmitted the bacteria to the musk oxen.

The musk oxen population in Canada has declined since the late 1990s, partly due to declining population trends in the population on Banks Island, according to the Arctic Report Card released in 2013 by the U.S. National Oceanic and Atmospheric Administration.

Both species are Arctic icons and they are important to the Inuit and Dene for food, income and cultural activities.

More Precipitation with Less Arctic Sea Ice

Melting sea ice has led to more precipitation in the Canadian Arctic and Greenland, according to new research.

Scientists thought less sea ice would cause more evaporation and precipitation in the region, but they lacked the observational data to show it. In the new study, the scientists analyzed precipitation data collected between 1990 and 2012 at three sites in the Canadian Arctic and three in the Greenland Sea, the Associated Press reported.

When the area of Arctic sea ice decreased by 100,000 square kilometers (38,610 square miles) precipitation jumped by 18.2 percent in the Canadian Arctic and by 10.8 percent in the Greenland Sea. “We show that the loss of sea ice will likely increase precipitation, which will impact communities and ecosystems around the Arctic,” lead author Ben Kopec, a Ph.D. candidate at Dartmouth College in Hanover, New Hampshire, said in a statement.

The researchers couldn’t say whether the increased precipitation would fall as snow or rain – and have a cooling or warming effect. Snow is more reflective than water and could help reflect the sun’s energy back into space, cooling the local climate, but rain would further warm the region and the planet.

Recommended Reads

• Politico Magazine: How Obama let Big Oil Drill in the Pristine Alaska Wilderness
• Alaska Dispatch News: Q&A with Fran Ulmer
• The Week: Real-Life Reindeer Games
• Al Jazeera: Permafrost: What Lies Beneath
• High Country News: Meet the Caribou Hunter of Arctic Village, Alaska

Top Image: Ben Kopec, a Ph.D. candidate in Dartmouth College’s Department of Earth Sciences, and his colleagues find that the melting of sea ice will significantly increase Arctic precipitation, creating a climate feedback comparable to doubling global carbon dioxide. (Foter.com/Derek Keats)