Arctic greening thaws permafrost, boosts runoff

Arctic greening thaws permafrost, boosts runoff

SOURCE: Los Alamos National Laboratory DATE: October 17, 2018 SNIP: A new collaborative study has investigated Arctic shrub-snow interactions to obtain a better understanding of the far north’s tundra and vast permafrost system. Incorporating extensive in situ observations, Los Alamos National Laboratory scientists tested their theories with a novel 3D computer model and confirmed that shrubs can lead to significant degradation of the permafrost layer that has remained frozen for tens of thousands of years. These interactions are driving increases in discharges of fresh water into rivers, lakes and oceans. “The Arctic is actively greening, and shrubs are flourishing across the tundra. As insulating snow accumulates atop tall shrubs, it boosts significant ground warming,” said Cathy Wilson, Los Alamos scientist on the project. “If the trend of increasing vegetation across the Arctic continues, we’re likely to see a strong increase in permafrost...
Acid is dribbling out of the melting permafrost in the Arctic

Acid is dribbling out of the melting permafrost in the Arctic

SOURCE: New Scientist ($$), Skeptical Science DATE: September 14, 2018 SNIP: Some patches of Arctic permafrost are bleeding acid as they melt. The dribble of acid is destroying rocks and releasing more carbon dioxide into the air – but it’s not clear how much. Permafrost is soil and sand that is permanently frozen. Climatologists have warned for years that Arctic permafrost is thawing due to climate change. This will transform the landscape, and release carbon that is locked away in the permafrost in the form of carbon dioxide and methane – adding to the greenhouse effect. However, most climatologists think the extra warming will be minor compared to that directly caused by our emissions. Now it seems that some regions of the Arctic might release more carbon dioxide than...
Greenhouse emissions from Siberian rivers peak as permafrost thaws

Greenhouse emissions from Siberian rivers peak as permafrost thaws

SOURCE: Umeå University DATE: September 4, 2018 SNIP: As permafrost degrades, previously frozen carbon can end up in streams and rivers where it will be processed and emitted as greenhouse gases from the water surface directly into the atmosphere. Quantifying these river greenhouse gas emissions is particularly important in Western Siberia – an area that stores vast amounts of permafrost carbon and is a home to the Arctic’s largest watershed, Ob’ River. Now researchers from Umeå University (and collaborators from SLU, Russia, France, and United Kingdom) have shown that river greenhouse gas emissions peak in the areas where Western Siberian permafrost has been actively degrading and decrease in areas where climate is colder, and permafrost has not started to thaw yet. The research team has also found out that greenhouse gas emissions from rivers exceed the amount of carbon that rivers transport to the Arctic Ocean. “This was an unexpected finding as it means that Western Siberian rivers actively process and release large part of the carbon they receive from degrading permafrost and that the magnitude of these emissions might increase as climate continues to warm” says Svetlana Serikova, doctoral student in the Department of Ecology and Environmental sciences, Umeå University, and one of the researchers in the...
Some Arctic Ground No Longer Freezing—Even in Winter

Some Arctic Ground No Longer Freezing—Even in Winter

SOURCE: National Geographic DATE: August 20, 2018 SNIP: Every winter across the Arctic, the top few inches or feet of soil and rich plant matter freezes up before thawing again in summer. Beneath this active layer of ground extending hundreds of feet deeper sits continuously frozen earth called permafrost, which, in places, has stayed frozen for millennia. Nikita Zimov, like his father, Sergey Zimov, has spent years running a research station that tracks climate change in the rapidly warming Russian Far East. [I]n a region where temperatures can dip to 40 degrees below zero Fahrenheit, the Zimovs say unusually high snowfall this year worked like a blanket, trapping excess heat in the ground. They found sections 30 inches deep—soils that typically freeze before Christmas—that had stayed damp and mushy all winter. For the first time in memory, ground that insulates deep Arctic permafrost simply did not freeze in winter. “This really is astounding,” says Max Holmes, an Arctic scientist with Woods Hole Research Center in Massachusetts. Already, three of the last four years have been earth’s hottest on record, with 2018 on schedule to be number four. And the poles are actually warming far faster, with areas 300 miles north of the Arctic Circle in Norway reaching 90 degrees Fahrenheit this July. If significant quantities of permafrost start thawing early, that would only make things worse. Permafrost temperatures across the Arctic have been rising since at least the 1970s—so much that small-scale localized thawing is already underway in many places. But the vast majority of this frozen land is still insulated by an active layer of freezing and thawing...
Impact of natural greenhouse emissions on Paris targets revealed

Impact of natural greenhouse emissions on Paris targets revealed

SOURCE: Centre of Ecology and Hydrology, National Environment Research Council DATE: July 9, 2018 SNIP: Global fossil fuel emissions would have to be reduced by as much as 20% more than previous estimates to achieve the Paris Agreement targets, because of natural greenhouse gas emissions from wetlands and permafrost, new research has found. The additional reductions are equivalent to 5-6 years of carbon emissions from human activities at current rates, according to a new paper led by the UK’s Centre for Ecology & Hydrology. Natural wetlands are very wet regions where the soils emit methane, which is also a greenhouse gas. The methane emissions are larger in warmer soils, so they will increase in a warmer climate. Permafrost regions are those which are permanently frozen. Under a warming climate permafrost regions begin to thaw and as a result the soils begin to emit carbon dioxide, and in some cases methane, into the atmosphere. The greenhouse gas emissions from natural wetland and permafrost increase with global temperature increases, this in turn adds further to global warming creating a “positive feedback”...