Global climate change is causing temperatures to rise sharply, especially in the Arctic. Among other things, higher temperatures are causing more and more permafrost soils, which have been frozen for thousands of years, to thaw. Particularly affected is so-called ‘yedoma’ permafrost, which is widespread in areas that were not covered by ice sheets during the last ice age. Yedoma contains up to 80 per cent ice and is therefore also called ice complex. The ground ice can thaw very abruptly, causing the bedrock to collapse and erode. Such processes, known as thermokarst, make carbon previously stored in the frozen ground accessible to microorganisms, which break it down and release it as carbon dioxide and methane. The greenhouse gas release amplifies global warming, which is known as permafrost-carbon feedback.
So far, there are still many uncertainties about the amount of future greenhouse gas release. Among other things, it is not clear how well the ancient carbon that has been frozen in permafrost for thousands of years can be degraded. To find out, the research team took carbon dioxide samples at the Siberian investigation site on the
— source University of Cologne | Jan 28, 2022