Contribution of glacier runoff to freshwater discharge into the Gulf of Alaska

Edward G. Neal; Eran Hood; K. Smikrud

doi:10.1029/2010gl042385

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Contribution of glacier runoff to freshwater discharge into the Gulf of Alaska

Edward G. Neal·Eran Hood·K. Smikrud

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Abstract

Watersheds along the Gulf of Alaska (GOA) are undergoing climate warming, glacier volume loss, and shifts in the timing and volume of freshwater delivered to the eastern North Pacific Ocean. We estimate recent mean annual freshwater discharge to the GOA at 870 km 3 yr −1 . Small distributed coastal drainages contribute 78% of the freshwater discharge with the remainder delivered by larger rivers penetrating coastal ranges. Discharge from glaciers and icefields accounts for 47% of total freshwater discharge, with 10% coming from glacier volume loss associated with rapid thinning and retreat of glaciers along the GOA. Our results indicate the region of the GOA from Prince William Sound to the east, where glacier runoff contributes 371 km 3 yr −1 , is vulnerable to future changes in freshwater discharge as a result of glacier thinning and recession. Changes in timing and magnitude of freshwater delivery to the GOA could impact coastal circulation as well as biogeochemical fluxes to near-shore marine ecosystems and the eastern North Pacific Ocean.

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Geophysical Research Letters Article

Source-reported bounding extent: 54.27825021068048° to 62.42585111921909° latitude; -160.5686468615533° to -126.9202647445766° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Edward G. Neal, Eran Hood, K. Smikrud. 2010-03-17. Contribution of glacier runoff to freshwater discharge into the Gulf of Alaska. https://doi.org/10.1029/2010gl042385

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