Attempting to understand the ‘carbon bomb’

AlaskaPermafrostMap_Front_Dec2008_Jorgenson_etal_2008.jpg

Alaska is characterized by many different types of permafrost, or soil that stays frozen year-round. The map shows types of permafrost and their locations around Alaska, as well as how deep the permafrost runs. The map was created by the Institute of Northern Engineering and the University of Alaska Fairbanks in 2008.

Permafrost is a major factor in climate change that has both local and global implications. But why should we care about something that’s been dead and frozen for thousands of years? Geologist Ronald Daanen, of The Division of Geological and Geophysical Surveys (DGGS), is explaining why in his presentation on local permafrost and associated hydrologic shifts at the university. Specifically, he’s focusing on the Goldstream Valley.

“Everyone’s afraid of the carbon bomb called permafrost,” Daanen said, “the carbon that’s stored in permafrost is being released due to warming temperatures. Bacteria attack that carbon and convert it to methane.”

So permafrost, one of the biggest carbon stores in the world (with one estimate at more than twice the global atmospheric carbon), is releasing carbon and converting it into methane. Estimates gauge methane’s efficacy as a greenhouse gas from 4 – 15 times that of carbon dioxide given the same amount of each. In other words, the release of substantial amounts of methane could lead to more serious climatic effects, than the release of the same amount of carbon dioxide. That means the ramifications for permafrost and its conversion to methane are extremely serious.

As you might imagine, a lot of research goes into permafrost melt. The major difference with Daanen’s work is that he is one of the few researchers examining melt from the bottom of the permafrost. Most studies today focus on permafrost melt from the top.

“Melt at the bottom of permafrost has been happening longer than melt at the top,” Daanen said, “more permafrost volume has been lost from the bottom than at the top. What that means for the carbon in the atmosphere is what we are trying to answer.”

So how is he able to measure climate impact on something buried well beneath the ground? Electromagnetic surveys: DGGS flies an electromagnetic system over the ground to measure the strength of electrical current in the ground. These currents depend on the amount of liquid water present in the ground, if areas are frozen they have much less liquid water than areas that are thawed and thus much less current.

Daanen’s presentation will provide a much more in-depth understanding and is taking place in Akasofu 401 on Nov. 16 at noon as part of the American Water Resources Association meeting. You can also attend via WebEx, provided you email event contact Molly Tedesche beforehand.

And in regards to permafrost, we need to drop temperatures not (carbon) bombs.

You may also like...

Leave a Reply

Your email address will not be published. Required fields are marked *