Managing Uncertainty: Strategic Downscaling of Climate Change Impacts on CCS Oceanography and Fisheries
Elizabeth Drenkard, NOAA Geophysical Fluid Dynamics Laboratory, Princeton, United States, Charles A Stock, NOAA/OAR/Geophysical Fluid Dynamics Laboratory, Princeton, United States, Arthur J Miller, University of California San Diego, La Jolla, CA, United States, Sam McClatchie, NOAA Fisheries, SWFSC, La Jolla, CA, United States and Enrique N Curchitser, Rutgers University New Brunswick, Department of Environmental Sciences, New Brunswick, NJ, United States
Abstract:
Climate change poses an unprecedented challenge for marine resource managers: rising temperatures, altered ocean chemistry, and circulation patterns will affect habitat suitability for many living marine resources (LMRs), including valuable U.S.-west coast fisheries. Downscaled global projections are useful for anticipating regional changes in ocean conditions. However, computational limitations necessitate frugality in designing experiments that comprehensively represent uncertainty across factors such as emission scenarios, global and regional model configurations, and internal climate variability.
As an example, we present findings of a projected northward shift in sardine spawning habitat suitability and discuss our methodology in the context of proposed "best practices" for dynamical downscaling. Specifically, we used output from climatologically forced historical (1981-2010) and future (2071-2100; NCAR LENS delta-addition) simulations of a Regional Ocean Modeling System (ROMS) model of the California Current System (CCS) to inform a general additive model that predicts probability of sardine egg-presence. These findings will be compared with preliminary results from a similarly configured regional Modular Ocean Model (MOM6) of the CCS to illustrate important considerations in generating strategic ensembles of downscaled climate change projections for the purpose of LMR management.
