The biggest negative feedback loop I am aware of is clouds. Higher temp, more moisture in the air, more clouds, greater reflection of incoming light (and greate

The biggest negative feedback loop I am aware of is clouds. Higher temp, more moisture in the air, more clouds, greater reflection of incoming light (and greater retention of heat, so not a clear negative loop in all scenarios). However, as far as I can tell, clouds are a lot easier to model than the positive feed back loops we know/suspect, albedo decrease, clathrate guns, peat breakdown, etc. Thus, we are in a situation, where negative feedback loops seem well accounted for and there are a few potentially catastrophic, but perfectly plausible, positive feedback loops that are too difficult to properly assess. It is scary.