Modeling the impacts of climate change on mass balance and discharge of Eklutna Glacier, Alaska, 1985–2019

Abstract Alaska's largest city, Anchorage, depends on Eklutna Glacier meltwater for drinking water and hydropower generation; however, the 29 km 2 glacier is rapidly retreating. We used a temperature-index model forced with local weather station data to reconstruct glacier's mass balance period 1985–2019 quantify impacts of change discharge. Model calibration involved novel combination in situ, geodetic mass-balance measurements observed snowlines from satellite imagery. A resulting ensemble 250 best-fitting parameters was experienced significant negative trend (?0.31 m w.e. decade ?1 ) annual mean surface (mean: ?0.62 ± 0.06 w.e.). The day year when 95% melt occurs five days later 2011–19 than 1985–93, demonstrating prolongation season (May–September). Modeled specific discharge increased at 0.14 , indicating peak water, reaches maximum due retreat, has not been reached. Four highest years occurred since 2000. Increases quantity length require resource managers consider future decreased as continues shrink.