9.3 Extreme Events
Climate change is increasing the frequency and intensity of extreme weather events: heatwaves, heavy precipitation, droughts, and tropical cyclones.
Attribution Science
Attribution studies quantify how much climate change contributed to specific events:
Heatwaves
Clear signal. 2021 Pacific NW heat: virtually impossible without climate change.
Heavy Precipitation
~7% more moisture per °C warming (Clausius-Clapeyron).
Droughts
Regional patterns vary. Increased evaporation worsens impacts.
Probability Shift
A small shift in the mean causes large changes in tail probabilities. What was a 1-in-50 year event may become 1-in-10 years.