Scientists discovered something alarming seeping out from beneath the ocean around Antarctica | CNN
www.cnn.com
Planet-heating methane is escaping from cracks in the Antarctic seabed, with new seeps being discovered at an “astonishing rate,” raising fears that future global warming predictions may have been underestimated.

I’ll note that there are similar seeps in the arctic.

This is likely a fairly modest effect compared with other sources of methane.