Melt water input from the Bering Glacier watershed into the Gulf of Alaska

The annual runoff from the melting of large glaciers and snow fields along the northern perimeter of the Gulf of Alaska is a critical component of marine physical and biological systems; yet, most of this freshwater is not measured. Here we show estimates of melt for the watershed that contains the largest and longest glacier in North America, the Bering Glacier. The procedure combines in situ observations of snow and ice melt acquired by a long-term monitoring program, multispectral satellite observations, and nearby temperature measurements. The estimated melt is 40 km³ per melt season, ± 3.0 km³, observed over the decadal period, 2002-2012. As a result of climate change, these estimates could increase to 60 km³/yr by 2050. This technique and the derived melt coefficients can be applied to estimate melt from Alaska to Washington glaciers. Key Points In-situ melt, temperature, and satellite data used to estimate glacier discharge Annually 40 km³ freshwater discharged to Gulf of Alaska from Bering Watershed Derived melt coefficients can be applied to estimate melt from N.A. glaciers