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Title: Moored Observations of the West Greenland Coastal Current along the Southwest Greenland Shelf
Abstract

We present the first continuous mooring records of the West Greenland Coastal Current (WGCC), a conduit of fresh, buoyant outflow from the Arctic Ocean and the Greenland Ice Sheet. Nearly two years of temperature, salinity, and velocity data from 2018 to 2020 demonstrate that the WGCC on the southwest Greenland shelf is a well-formed current distinct from the shelfbreak jet but exhibits strong chaotic variability in its lateral position on the shelf, ranging from the coastline to the shelf break (50 km offshore). We calculate the WGCC volume and freshwater transports during the 35% of the time when the mooring array fully bracketed the current. During these periods, the WGCC remains as strong (0.83 ± 0.02 Sverdrups; 1 Sv ≡ 106m3s−1) as the East Greenland Coastal Current (EGCC) on the southeast Greenland shelf (0.86 ± 0.05 Sv) but is saltier than the EGCC and thus transports less liquid freshwater (30 × 10−3Sv in the WGCC vs 42 × 10−3Sv in the EGCC). These results indicate that a significant portion of the liquid freshwater in the EGCC is diverted from the coastal current as it rounds Cape Farewell. We interpret the dominant spatial variability of the WGCC as an adjustment to upwelling-favorable wind forcing on the West Greenland shelf and a separation from the coastal bathymetric gradient. An analysis of the winds near southern Greenland supports this interpretation, with nonlocal winds on the southeast Greenland shelf impacting the WGCC volume transport more strongly than local winds over the southwest Greenland shelf.

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Award ID(s):
1948505 2047952
NSF-PAR ID:
10473310
Author(s) / Creator(s):
 ;  
Publisher / Repository:
American Meteorological Society
Date Published:
Journal Name:
Journal of Physical Oceanography
Volume:
53
Issue:
11
ISSN:
0022-3670
Format(s):
Medium: X Size: p. 2619-2632
Size(s):
["p. 2619-2632"]
Sponsoring Org:
National Science Foundation
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