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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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Shelfbreak Jet Transport from OOI Pioneer
This repository contains hourly Shelfbreak jet transport (Sv) derived from the three central moorings of the OOI Coastal Pioneer Array (https://ooinet.oceanobservatories.org/). Transport is computed from east velocity component (u, in m/s), which is then depth integrated from 15 until 115m. The depth integrated velocity (m2/s) is transformed in transport considering a jet width of 40 km, and then converted into Sv (by dividing by 10^6 factor). Thus, to convert the transport time series back to m2/s, the time series must be divided by 4.10^10. Tides were removed from the velocity component, with Utide harmonic estimation, using the 68 standard tidal coefficients, except for the Semi-annual and Annual components (Sa and SSa). First column: date (datetime format, year-month-day hour:min:second)Second column: Qy (jet transport, in Sv) accompanying paper: Camargo, C. M. L., Piecuch, C. G., & Raubenheimer, B. (2024). From Shelfbreak to Shoreline: Coastal sea level and local ocean dynamics in the northwest Atlantic. Geophysical Research Letters, 51, e2024GL109583. https://doi.org/10.1029/2024GL109583
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- Award ID(s):
- 2244833
- PAR ID:
- 10627718
- Publisher / Repository:
- Zenodo
- Date Published:
- Format(s):
- Medium: X
- Right(s):
- Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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