Oceanic Response to a Coastal Polynya, Terra Nova Bay, Antarctica

Lead PI: Dr. Christopher J. Zappa , Professor Arnold L. Gordon

Unit Affiliation: Ocean and Climate Physics, Lamont-Doherty Earth Observatory (LDEO)

September 2014 - August 2018
Inactive
Antarctica
Project Type: Research

DESCRIPTION: Antarctic coastal polynyas are, at the same time, sea-ice free sites and sea-ice factories. They are open water surface locations where water mass transformation and densification occurs, and where direct atmospheric exchanges with the deep ocean circulation are established. Various models of the formation and persistence of these productive and diverse ocean ecosystems are hampered by the relative lack of in situ meteorological and physical oceanographic observations. This is especially so during the inhospitable conditions of their formation and activity during autumn to winter transition and the polar night. The Western Ross Sea, downstream from two of the largest coastal Antarctic polynyas, happens to be a region where there continues to be net sea-ice production, as indicated by satellite measurements of areal extent, duration and concentration. Characterization of the lower atmosphere properties, air-sea surface heat fluxes and corresponding ocean depth profiles of the Terra Nova Bay (TNB) polynya, is sought for a more detailed understanding of the role of polynyas in the production of latent-heat type sea ice and the formation, through sea ice brine rejection, of dense ocean bottom waters. This observational program will simultaneously identify mechanisms responsible for water mass modification within TNB and document aspects of dense shelf water formation within a large Antarctic polynya system. This study will characterize the water masses within a polyna over the course of an annual cycle using moorings yielding in-situ column and near-surface oceanic observation.

SPONSOR:

National Science Foundation (NSF)

FUNDED AMOUNT:

$898,464

WEBSITE:

https://www.nsf.gov/awardsearch/showAward?AWD_ID=1341688&HistoricalAwards=false

PUBLICATIONS:

Robin E. Bell Winnie Chu Jonathan Kingslake Indrani Das Marco Tedesco Kirsty J. Tinto Christopher J. Zappa Massimo Frezzotti Alexandra Boghosian Won Sang Lee. "Antarctic ice shelf potentially stabilized by export of meltwater in surface river," Nature, v.544, 2017, p. 344. doi:doi:10.1038/nature22048

Christine F. Dow Won Sang Lee Jamin S. Greenbaum Chad A. Greene Donald D. Blankenship Kristin Poinar Alexander L. Forrest Duncan A. Young Christopher J. Zappa. "Basal channels drive active surface hydrology and transverse ice-shelf fracture," Science Advances, v.4, 2018. doi:eaao7212

KEYWORDS

water mass modification deep ocean circulation sea ice polynya