[PAST EVENT] Enhanced warming of the U.S. Northeast Continental Shelf under climate change

October 28, 2015
12pm - 1pm
VIMS - Watermen's Hall, Classroom A/B
1375 Greate Road
Gloucester Point, VA 23062Map this location
Fisheries Science Noon Seminar Series

Speaker: Vincent Saba

Title: Enhanced warming of the U.S. Northeast Continental Shelf under climate change: Implications for fisheries

Abstract: Over the past 20 years, sea surface temperature in the United States Northeast Continental Shelf (U.S. NES) has warmed at a substantially higher rate than the global average. Presently, all climate change projections for living marine resources (cod, croaker, cusk, river herring) within the U.S. NES have been based on IPCC-class climate models that have a coarse ocean resolution (1o x1o global). These coarse models do not resolve the fine-scale bathymetry (i.e. Georges Bank, Northeast Channel) of the U.S. NES, nor do they resolve the correct position of the Northwestern Wall of the Gulf Stream. In this study, high-resolution global climate models were used from the NOAA Geophysical Fluid Dynamics Laboratory to assess differences in climate change projections for the U.S. NES as a function of climate model resolution. We found that the high-resolution climate model (0.1o x 0.1o global ocean) resolves U.S. NES bathymetry and water mass circulation much more accurately than the standard coarse models. Climate change projections of sea surface temperature and bottom temperature within the U.S. NES based on the high-resolution model are up to 1.5oC (surface) to 3oC (bottom) warmer than the projections based on the coarse models. This enhanced warming is accompanied by an increase in salinity due to a change in water mass distribution that is related to a retreat of the Labrador Current and a northerly shift of the Gulf Stream. Both observations and the high-resolution climate model's response to an atmospheric CO2 doubling demonstrate a robust relationship between a weakening Atlantic Meridional Overturning Circulation (AMOC) and an increase in the proportion of Warm-Temperate Slope Water entering the U.S. NES, which is responsible for much of the enhanced warming. Therefore, existing climate change and living marine resource projections for the U.S. NES are based on a warming that is likely far too conservative. Finally, some preliminary results regarding climate change projections for the Chesapeake Bay as a function of model resolution will also be presented as well as U.S. NES species assemblage projections based on observations from the Northeast Fisheries Science Center bottom-trawl survey.

Biopic: Dr. Vincent Saba is a Research Fishery Biologist with the Northeast Fisheries Science Center's Ecosystem Assessment Program. He resides at the NOAA Geophysical Fluid Dynamics Laboratory (GFDL) in Princeton, New Jersey. Dr. Saba received a B.S. and M.S in Environmental Science from Drexel University. He earned a Ph.D. in Marine Science from the College of William and Mary - Virginia Institute of Marine Science. His research focuses on climate impacts on marine ecosystems. His research scales the marine food web ranging from phytoplankton to top predators. Much of his current research involves the use of NOAA GFDL's high-resolution global climate models for their use in regional marine ecosystems such as the U.S. Northeast Continental Shelf.

[[v|dmk,Professor David Kaplan]]