THE END OF THE ICE-AGE

Methane-gas hydrates may have contributed to the rapid rise in atmospheric CH4, CO2, and global temperatures at the end of the last major glaciation about 13 500 years ago. Given suitable orbital conditions and insolation at high latitude, a small triggering event, such as the release of one or more Arctic gas pools, may have initiated massive release of methane from hydrate under ice and in permafrost. The consequent greenhouse warming would have provided strong positive feedback, amplifying emission. This warming, driven by CH4, may have induced the release of CO2from the oceans to the biosphere, stabilizing the interglacial carbon cycle. © 1990, Canadian Science Publishing. All rights reserved.