Forests buffer thermal fluctuation better than non-forests

biodiversity. We compared thermal buffer ability (TBA) of ten vegetation types over the world. TBA was calculated using the increasing rate of outgoing longwave radiation with incoming shortwave radiation (SlopeL). Forests showed lower SlopeL than non-forests, but their differences decreased in cold region. The disturbed or young forests in cold region even had higher SlopeL than non-forests. Wetlands had comparable TBA with forests. Open shrublands, savanna, grasslands and croplands had the lowest TBA. SlopeL was driven by energy, carbon exchange, as well as vegetation structure. Forest heights were negatively related to SlopeL. The reduction of radiation by albedo had almost no effects on SlopeL. Except for relative humidity and precipitation, environmental factors had no impacts on SlopeL. Our results stress the necessity to control forest disturbance in cold region, and provide a potential way to improve vegetation indices.