Climate Change Projections from High-Resolution Global Models and the Implications for Fisheries Management in the U.S. Northeast Shelf Ecosystem

Over the past 20 years, ocean surface temperature in the United States Northeast Shelf (U.S. NES) has warmed at a substantially higher rate than the global average.  To date, all climate change projections for species within the U.S. NES have been based on climate models that have a coarse ocean resolution (1^o x1^o 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.  Here we used high-resolution global climate models from the NOAA Geophysical Fluid Dynamics Laboratory to assess differences in climate change projections for the U.S. NES as a function model resolution.  We found that the high-resolution climate model (0.1^o x 0.1^o global ocean) resolves 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 1.5^oC (surface) to 3^oC (bottom) warmer than the projections based on the coarse models. Therefore, existing projections for the U.S. NES are conservative and thus impacts to fisheries may be greater than the current climate change projections.