Extreme Precipitation Events in Alaska: Historical Trends and Projected Changes

While recent increases in heavy precipitation events some midlatitude regions are consistent with climate model simulations, evidence of such high latitudes is more tenuous, partly because data limitations. The present study evaluates historical and future changes extreme Alaska. Using the ERA5 reanalysis, station data, output from two downscaled global models, we examine precipitation-driven flood at five diverse locations Alaska where major floods provide benchmarks: Fairbanks (August 1967), Seward (October 1986), Allakaket/Bettles 1994), Kivalina 2012), Haines (December 2020). We place these into a framework trends end-of-century (2065–2100) projections. In all but one events, amount rainfall was highest on record for event duration, this magnitude generally projected by models to remain infrequent. All cases had subtropical or tropical moisture sources. None show statistically significant events. However, frequencies increase most locations. frequency 2 year 5 return intervals become frequent, especially Interior, several times per year. Decreases only along Alaska’s southern coast.