claim: Previous studies have shown that weakening carbon sinks will add 0.25°C, forest dieback will add 0.11°C, permafrost thaw will add 0.9°C and increased bacterial respiration will add 0.02°C.
evidence: The New York Times reported that "the leading international network of climate scientists has concluded for the first time that global warming is 'unequivocal' and that human activity is the main driver, 'very likely' causing most of the rise in temperatures since 1950".