The great methane sinks of the Arctic starting to vent

Warming seas lead to the possible release of methane hydrates trapped in sub-oceanic sediments: methane fireballs tear across the sky, causing further warming. The oceans lose their oxygen and turn stagnant, releasing poisonous hydrogen sulphide gas and destroying the ozone layer. Deserts extend almost to the Arctic. "Hypercanes" (hurricanes of unimaginable ferocity) circumnavigate the globe, causing flash floods which strip the land of soil.
And a new discovery raises fresh questions about the speed at which sea levels might rise in a warmer world due to the rate at which parts of the ice sheets slide from the land into the ocean,
Humanity reduced to a few survivors eking out a living in polar refuges.