August 24, 2017
Alaskan permafrost is thawing, and here’s why that’s a big problem
With a name like “permafrost,” one would probably think that the frozen terrain in sub-Arctic Alaska would be safe from the effects of global climate change, but scientists from Woods Hole Research Center now say that is not the case – and that could be bad news for the planet.
In a New York Times report published earlier this week, researchers at the Massachusetts-based facility explained that the perennially-frozen ground found throughout much of the state is now beginning to thaw, and that this process could result in even greater levels of global warming.Scientists believe that permafrost, which can reach depths of hundreds of feet below the surface, contains copious amounts of carbon dioxide trapped in organic matter, the newspaper explained. Specifically, this CO2 was captured by plants that died and became frozen before they were able to decompose. Should those plants thaw, that carbon could be released into the atmosphere.
Theoretically, that could double the amount of CO2 that is currently in the atmosphere, and that, in turn, could increase global warming by as much as 1.7 degrees Fahrenheit during the centuries to come. While the Alaskan permafrost is just one part of that equation, the researchers warn that the region is less than one-half degree below freezing at a depth of three feet below the ground.
In fact, the region could lose a significant amount of its permafrost by the middle of the century, Woods Hole deputy director and senior scientist Dr. Max Holmes told the Times. That, he noted, would likely have “all kinds of consequences both locally for this region, for the animals and the people who live here, as well as globally.”
Scientists detect a 3- to 5-degree increase in ground temperatures
While permafrost is often referred to as permanently frozen ground, it is actually more correctly defined as soil, rock and sand which has been frozen for a period of at least two years, according to National Geographic. In addition to Alaska, it can be found in parts of Russia, Canada, China and Eastern Europe – places where temperatures rarely surpass freeing, the publication said.
In July, Holmes and a group of researchers from Woods Hole and The Polaris Project established a field station at an unnamed lake located near the town of Bethel, the Times reported. Next, they drilled permafrost cores using an instrument known as a power augur, placed temperature probes into the ground, and collected and analyzed water and sediment samples.
What they found was that even in colder parts of northern Alaska, where the permafrost extended to more than 2,000 feet beneath the ground, temperatures at depths of 65 feet had increased by at least 3.0 degrees Celsius (approximately 5.5 degrees Fahrenheit) over the past few decades. Near the surface, the changes have been even more pronounced, they said – shallow regions have gone from -8.0 degrees Celsius to -3.0 degrees Celsius.
The findings indicate that permafrost “is not as stable as people thought,” research team member Dr. Vladimir E. Ramonovsky from the University of Alaska, Fairbanks told the Times. If trends continue, he said, near-surface temperatures would heat to above freezing by midcentury, which would lead to a slow but gradual increase CO2 and greenhouse gas emissions – not to mention a significant increase in water level and land loss as the ice begins to melt.
Dr. Holmes told the newspaper that the observations were not surprising, given recent trends in climate. He said that the odds are good that other regions of permafrost are experiencing similar heating, and that is bad news for atmospheric greenhouse gas levels. “There’s a massive amount of carbon that’s in the ground, that’s built up slowly over thousands and thousands of years,” he explained. “It’s been in a freezer, and that freezer is now turning into a refrigerator.”
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