Thanks, wili. One of your quotes was slightly changed by the Climate Central journalist:
...a spike in global methane concentrations in the atmosphere seen since 2007 can be partly traced back to the formation of fens in areas where permafrost once existed...
(He added the word "partly"). The original news release from University of Guelph is
here.
The increase since 2007 is also partly attributed to tropical wetlands, industrial gas leaks, etc. Here's a nice 1-page summary paper by Nisbet et al. 2014:
Methane on the Rise - Againwith the following image of methane growth rate by latitude:
