The role of atmospheric forcing versus ocean advection during the extreme warming of the Northeast U.S. continental shelf in 2012
Gawarkiewicz, Glen G.
Zhang, Weifeng G.
MetadataShow full item record
KeywordExtreme temperature; Heat budget; Northeast U.S. coastal ocean; Numerical modeling; Air-sea interaction; Climate change
In the coastal ocean off the Northeast U.S., the sea surface temperature (SST) in the first half of 2012 was the highest on the record for the past roughly 150 years of recorded observations. The underlying dynamical processes responsible for this extreme event are examined using a numerical model, and the relative contributions of air-sea heat flux versus lateral ocean advective heat flux are quantified. The model accurately reproduces the observed vertical structure and the spatiotemporal characteristics of the thermohaline condition of the Gulf of Maine and the Middle Atlantic Bight waters during the anomalous warming period. Analysis of the model results show that the warming event was primarily driven by the anomalous air-sea heat flux, while the smaller contribution by the ocean advection worked against this flux by acting to cool the shelf. The anomalous air-sea heat flux exhibited a shelf-wide coherence, consistent with the shelf-wide warming pattern, while the ocean advective heat flux was dominated by localized, relatively smaller-scale processes. The anomalous cooling due to advection primarily resulted from the along-shelf heat flux divergence in the Gulf of Maine, while in the Middle Atlantic Bight the advective contribution from the along-shelf and cross-shelf heat flux divergences was comparable. The modeling results confirm the conclusion of the recent analysis of in situ data by Chen et al. (2014a) that the changes in the large-scale atmospheric circulation in the winter of 2011–2012 primarily caused the extreme warm anomaly in the spring of 2012. The effect of along-shelf or cross-shelf ocean advection on the warm anomalies from either the Scotian Shelf or adjacent continental slope was secondary.
Author Posting. © American Geophysical Union, 2015. 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: Oceans 120 (2015): 4324–4339, doi:10.1002/2014JC010547.
Showing items related by title, author, creator and subject.
Ummenhofer, Caroline C.; Sen Gupta, Alexander; England, Matthew H.; Taschetto, Andrea S.; Briggs, Peter R.; Raupach, Michael R. (John Wiley & Sons, 2015-11-19)Extreme rainfall conditions in Australia during the 2010/2011 La Niña resulted in devastating floods claiming 35 lives, causing billions of dollars in damages, and far-reaching impacts on global climate, including a ...
Thorrold, Simon R.; Afonso, Pedro; Fontes, Jorge; Braun, Camrin D.; Santos, Ricardo S.; Skomal, Gregory B.; Berumen, Michael L. (Nature Publishing Group, 2014-07-01)Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food ...
Diversity and distribution of subseafloor Thermococcales populations in diffuse hydrothermal vents at an active deep-sea volcano in the northeast Pacific Ocean Huber, Julie A.; Butterfield, David A.; Baross, John A. (American Geophysical Union, 2006-12-20)The presence, diversity, and distribution of a key group of subseafloor archaea, the Thermococcales, was examined in multiple diffuse flow hydrothermal vents at Axial Seamount, an active deep-sea volcano located in the ...