Abstract
Atmospheric rivers (ARs) transport vast amounts of moisture from low to
high latitude regions. One region particularly impacted by ARs is
Interior Alaska (AK). We analyze the impact of ARs on the annual river
ice breakup date for 25 locations in AK. We
investigate the AR-driven rise in local air temperatures and explore the
relationship between ARs and precipitation, including extremes and
interannual variability. We found that AR events lead to an increase in
local air temperatures for up to one week (by ≈ 1°C). Interannually, ARs
account for 36% of total precipitation, explain 48% of precipitation
variability, and make up 57% of extreme precipitation events. By
estimating the heat transfer between winter precipitation and the river
ice surface, we conclude that increased precipitation during the coldest
period of the year delays river ice breakup dates, while precipitation
occurring close to the breakup date has little impact on breakup timing.