[ApplegateRanch]

In the past, atmospheric methane levels have varied between .3 and .7 parts per million. Currently, the numbers are up to 1.85 parts per million -- a 400,000-year high. Above the East Siberian Arctic Shelf, this figure is even greater.

IIRC it has been at least 100,000-500,000 times higher in the past; the rest being mainly ammonia. Damned bacteria came along, contaminated the planet, and screwed up the balance. That gave all you Hooo-mons a nitrox mix, and there was nothing we could do about it, except retreat to Titan.

[SunkenCiv]

:’)