Methane is a powerful greenhouse gas, but it also has an awesome power to really get people worked up, compared to other equally frightening pieces of the climate story.

Very large quantities of methane gas are trapped in ocean-floor sediments due to pressure and temperature constraints. These frozen methane hydrates have been believed to become unstable in the past, namely at the Paleocene-Eocene Thermal Maximum (PETM) within the geologic record and this proposed vast methane release is believed to have caused or at least to have been a mechanism in the mass extinction at the end of the Permian Period. 

With the advent of current climate change and in particular, global warming, is it possible for anthropogenic actions to alter the stability of ocean bottom methane hydrates to the point of a vast methane 'bubble' release capable of causing a present day mass extinction?