Publications

Snow, T; Straneo, F; Holte, J; Grigsby, S; Abdalati, W; Scambos, T (2021). More than Skin Deep: Sea Surface Temperature as a Means of Inferring Atlantic Water Variability on the Southeast Greenland Continental Shelf Near Helheim Glacier. JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 126(4), e2020JC016509.

Abstract
Enhanced outlet glacier discharge accounts for almost half of the Greenland Ice Sheet's mass loss since 1990. Warming subsurface Atlantic Water (AW) has been implicated in much of that loss, particularly along Greenland's southeastern coast. However, oceanographic observations are sparse prior to the last decade, making it difficult to diagnose changes in AW properties reaching the glaciers. Here, we investigate the use of sea surface temperature (SST) measurements to quantify ocean temperature variability on the continental shelf near Sermilik Fjord and Helheim Glacier. We find that after removing the short-term, atmospheric-driven variability in non-winter months, regional SSTs provide a reliable upper ocean (surface mixed layer) temperature record. In the trough region near Sermilik Fjord, the adjusted SSTs correlate well with moored ocean measurements of the water entering the fjord at depth and driving glacier melting. Using this relationship, we reconstruct the AW variability on the shelf dating back to 2000, 8 years before the first mooring deployments. Across the 19-year record, the AW temperatures in the trough do not always track properties in the source waters of the Irminger Current, which flows along the continental break. Instead, the properties of the waters found at the fjord mouth depend on variations in the source AW and, also, in the Polar Water that flows into the region from the Arctic Ocean. Satellite-derived SSTs, when combined with local oceanography considerations, have the potential to improve understanding around previously unanswered glacier-ocean questions in areas surrounding Greenland.

DOI:
10.1029/2020JC016509

ISSN:
2169-9275