Science Source

Matthew G Cooper, Anne W Nolin, Mohammad Safeeq

Environmental Research Letters

Published date August 8, 2016

Testing the recent snow drought as an analog for climate warming sensitivity of Cascades snowpacks

States that record low snowpack conditions were observed at Snow Telemetry stations in the Cascades Mountains, USA during the winters of 2014 and 2015
Tests the hypothesis that these winters are analogs for the temperature sensitivity of Cascades snowpacks
States that in the Oregon Cascades, the 2014 and 2015 winter air temperature anomalies were approximately +2 °C and +4 °C above the climatological mean
Uses a spatially distributed snowpack energy balance model to simulate the sensitivity of multiple snowpack metrics to a +2 °C and +4 °C warming and compares modeled sensitivities to observed values during 2014 and 2015
Finds that for each +1 °C warming, modeled basin-mean peak snow water equivalent (SWE) declined by 22%–30%, the date of peak SWE (DPS) advanced by 13 days, the duration of snow cover (DSC) shortened by 31–34 days, and the snow disappearance date (SDD) advanced by 22–25 days
Results show that the hypothesis is borne out only by the peak SWE observations
Results indicate that rather than just temperature, the magnitude and phasing of winter precipitation events, such as large, late spring snowfall, controlled the DPS, SDD, and DSC