However, scientists are still debating just how much old carbon Arctic soils should release normally even without climate change, leaving the ultimate significance of the findings unclear. It found an increasing prevalence of older dissolved carbon and carbon dioxide in the waters as the summer advanced. Layer upon layer of Arctic soil has built up, representing a kind of time capsule with the oldest layers, and the oldest carbon, generally found at the greatest depths. Schuur said in an email that these studies, “taken together,” suggest that “increased old C release is a fingerprint of changing Arctic carbon cycle.”“Of course, magnitude matters, but I think the concept of old carbon entering the modern carbon cycle is an important one indicating change from the status quo,” Schuur added. Czimczik suggested that permafrost carbon isn’t really “old” or “ancient” until it has aged between 5,000 and 10,000 years.

Source: thestar March 01, 2018 22:41 UTC