Cirrus cloud feedback in response to climate fluctuations

Analysis of CALIPSO observations indicates that transparent cirrus clouds (optical depth<3.5) contribute a significant positive feedback on interannual climate fluctuations, due to increases in their fractional coverage amount and altitude in response to surface warming. It is estimated that the net feedback of cirrus is +0.23±0.22W/m2/°C, primarily contributed from tropical tropopause layer (TTL) and subtropical troposphere. The cirrus feedback is comparable to the albedo feedback and is important to the climate sensitivity.