Seasonal circulation under the eastern Ross Ice Shelf, Antarctia
Abstract
An annual cycle of shelf water temperatures and salinities measured at depth near the eastern Ross Ice Shelf front is used to force a two-dimensional thermohaline circulation model adapted to different subice paths in the vicinity of Roosevelt Island. These paths were assumed to have constant water column thicknesses of 160, 200, and 240 m and lengths of 460-800 km. Additional simulations with the longer cavity included a 80-m thick interior water column in order to approximate conditions closer to the grounding line. Model results were compared with other long-term measurements that showed outflow from beneath the ice shelf. Shelf water flowing into the cavity west of Roosevelt Island appears to follow a cyclonic route around the island. The ice shelf base loses mass at a rate of 18-27 cm yr{sup {minus}1}, with seasonal forcing increasing the spatial and temporal variability of circulation and property distributions in the larger cavities. Shallow cavities reduce the influence of shelf water variability with increasing length. Introducing a transient shelf water temperature rise of 0.01{degrees}C yr {sup {minus}1} for 100 years increases the melt rate by 4-5 times. However, this increase is smaller if salinity also decreases over the same period of time, asmore »
- Authors:
-
- Lamont-Doherty Earth Observatory Palisades, NY (United States)
- Publication Date:
- OSTI Identifier:
- 114918
- DOE Contract Number:
- FG02-93ER61716
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Geophysical Research
- Additional Journal Information:
- Journal Volume: 100; Journal Issue: C6; Other Information: PBD: 15 Jun 1995
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; ANTARCTIC OCEAN; ICE; WATER CURRENTS; SEASONAL VARIATIONS; OCEANIC CIRCULATION; SALINITY
Citation Formats
Hellmer, H H, and Jacobs, S S. Seasonal circulation under the eastern Ross Ice Shelf, Antarctia. United States: N. p., 1995.
Web. doi:10.1029/95JC00753.
Hellmer, H H, & Jacobs, S S. Seasonal circulation under the eastern Ross Ice Shelf, Antarctia. United States. https://doi.org/10.1029/95JC00753
Hellmer, H H, and Jacobs, S S. 1995.
"Seasonal circulation under the eastern Ross Ice Shelf, Antarctia". United States. https://doi.org/10.1029/95JC00753.
@article{osti_114918,
title = {Seasonal circulation under the eastern Ross Ice Shelf, Antarctia},
author = {Hellmer, H H and Jacobs, S S},
abstractNote = {An annual cycle of shelf water temperatures and salinities measured at depth near the eastern Ross Ice Shelf front is used to force a two-dimensional thermohaline circulation model adapted to different subice paths in the vicinity of Roosevelt Island. These paths were assumed to have constant water column thicknesses of 160, 200, and 240 m and lengths of 460-800 km. Additional simulations with the longer cavity included a 80-m thick interior water column in order to approximate conditions closer to the grounding line. Model results were compared with other long-term measurements that showed outflow from beneath the ice shelf. Shelf water flowing into the cavity west of Roosevelt Island appears to follow a cyclonic route around the island. The ice shelf base loses mass at a rate of 18-27 cm yr{sup {minus}1}, with seasonal forcing increasing the spatial and temporal variability of circulation and property distributions in the larger cavities. Shallow cavities reduce the influence of shelf water variability with increasing length. Introducing a transient shelf water temperature rise of 0.01{degrees}C yr {sup {minus}1} for 100 years increases the melt rate by 4-5 times. However, this increase is smaller if salinity also decreases over the same period of time, as might be expected from the added meltwater component. 42 refs., 9 figs.},
doi = {10.1029/95JC00753},
url = {https://www.osti.gov/biblio/114918},
journal = {Journal of Geophysical Research},
number = C6,
volume = 100,
place = {United States},
year = {Thu Jun 15 00:00:00 EDT 1995},
month = {Thu Jun 15 00:00:00 EDT 1995}
}