Why “Runaway”?

Posted on March 5, 2010 in What is RCC

“Runaway climate change” is what happens when global warming becomes self-sustaining. A global warming spiral kicks in if:

• The environment absorbs less CO2. About 50% of our current emissions are absorbed by the environment – roughly half of that by the oceans, the other half by plants on land. This uptake of CO2 by the environment may already be in decline.
• Reflection of sunlight drops. As snow and ice cover retreat – as cover is smaller in geographic extent, or seasonal cover lasts for less of the year – dark ground and even darker water are exposed, which absorb sunlight, further warming the earth.
• More CO2 and methane are emitted from nature. Soils, forests, peat, the seas, organic deposits in permafrost, and methane clathrates all emit some CO2 and methane. As the environment warms, “natural” emissions increase.