Apr 27, 2015

Anthropogenic contribution to global occurrence of heavy-precipitation and high-temperature extremes

E. M. Fischer, R. Knutti
Nature Climate Change
  • Applies a similar framework as past studies attributing specific heatwave and heavy precipitation events to human-caused climate change but estimates what fraction of all globally occurring heavy precipitation and hot extremes is attributable to warming
  • Shows that at the present-day warming of 0.85 °C about 18% of the moderate daily precipitation extremes over land are attributable to the observed temperature increase since pre-industrial times, which in turn primarily results from human influence
  • Finds that for 2°C of warming, the fraction of precipitation extremes attributable to human influence rises to about 40%.
  • Finds that today about 75% of the moderate daily hot extremes over land are attributable to warming
  • Holds it is the most rare and extreme events for which the largest fraction is anthropogenic, and that contribution increases nonlinearly with further warming
  • Asserts the approach introduced is robust owing to its global perspective, less sensitive to model biases than alternative methods and informative for mitigation policy, and thereby complementary to single-event attribution