Publication Date:
2022-05-25
Description:
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): C05022, doi:10.1029/2006JC003903.
Description:
A set of model simulations are used to determine the principal forcing mechanisms that resulted in anomalously cold water in the South Atlantic Bight (SAB) in the summer of 2003. Updated mass field and elevation boundary conditions from basin-scale Hybrid Coordinate Ocean Model (HYCOM) simulations are compared to climatological forcing to provide offshore and upstream influences in a one-way nesting sense. Model skill is evaluated by comparing model results with observations of velocity, water level, and surface and bottom temperature. Inclusion of realistic atmospheric forcing, river discharge, and improved model dynamics produced good skill on the inner shelf and midshelf. The intrusion of cold water onto the shelf occurred predominantly along the shelf-break associated with onshore flow in the southern part of the domain north of Cape Canaveral (29° to 31.5°). The atmospheric forcing (anomalously strong and persistent upwelling-favorable winds) was the principal mechanism driving the cold event. Elevated river discharge increased the level of stratification across the inner shelf and midshelf and contributed to additional input of cold water into the shelf. The resulting pool of anomalously cold water constituted more than 50% of the water on the shelf in late July and early August. The excess nutrient flux onto the shelf associated with the upwelling was approximated using published nitrate-temperature proxies, suggesting increased primary production during the summer over most of the SAB shelf.
Description:
The preparation of this paper was primarily
supported by the Southeast Atlantic Coastal Ocean Observing System
(SEACOOS) and the South Atlantic Bight Limited Area Model
(SABLAM). SEACOOS is a collaborative, regional program sponsored
by the Office of Naval Research under award N00014-02-1-0972 and
managed by the University of North Carolina-General Administration.
SABLAM was sponsored by the National Ocean Partnership Program
(award NAG 13-00041). Data from ship surveys were collected and
processed with the support from NSF grant OCE-0099167 (J. R. Nelson),
NSF grant OCE-9982133 (J. O. Blanton, SkIO), NASA grant NAG-10557
(J. R. Nelson), and SEACOOS. NOAA NDBC buoy data and NOS coastal
water level records were obtained through NOAA-supported data archives
and web portals. Moored instrument data from the Carolina Coastal Ocean
Observation and Prediction System (Caro-COOPS) were acquired from the
system’s website (http://www.carocoops.org). Caro-COOPS is sponsored
by NOAA grant NA16RP2543.
Keywords:
Summer upwelling
;
Model simulations
;
South Atlantic Bight
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
Permalink
