If the methane is datable by carbon 14 or other methods then we may decipher its' origin, and estimate how often these deposits recur. as @gkam notes, massive releases in the past may have ended various ice ages. I guess an underwater landslide might subduct warm surface waters with it and trigger a release.

And has before

And will again

tick tock tick tock

I for one have been walking to work for a while now. Its only a couple miles overall to the bus stops.