March 10, 2023 at 10:30am CT
Speaker: Liz Drenkard, Research Oceanographer, Geophysical Fluid Dynamics Laboratory, NOAA
Host: Patrick Heimbach
Title: Modeling the ocean at different scales for marine ecosystem management in a changing climate
Abstract: Earth System Models (ESMs) are invaluable for understanding the ocean’s role in climate change and anticipating future global ocean conditions. Ongoing model developments toward more holistic representation of the Earth System continue to shape our knowledge of global change but, in order to capture the regional ocean processes most relevant to coastal communities and the living marine resources (LMRs) on which they depend, these models sometimes need to be translated to smaller scales. Downscaling ESMs to limited area domains can address this need, but only with significant improvements relative to past efforts, including strategic budgeting of finite computational resources to balance resolution, uncertainty quantification, and comprehensiveness needs.
I will share some of my research at NOAA’s Geophysical Fluid Dynamics Laboratory where I use ocean models to study the effects of climate change on marine ecosystems at different scales. At the global-scale, I’ve been investigating the impact of advances in coupled land-air-sea interactions, specifically the dynamic deposition of dust to the ocean in GFDL’s ESM4, on projections of ocean biogeochemistry. We’ve found that permitting dust deposition to reflect changes in land use and aridity (rather than prescribing a deposition climatology to the ocean) dramatically impacts the distribution of Pacific Ocean iron limitation under different emission scenarios. At the regional scale, I will delve into recommendations for next-generation regional ocean projections for LMR management (e.g., considerations for model domain size, resolution, ensemble size) arising from a recent synthesis of two decades of ocean downscaling efforts. Finally, I will describe nascent NOAA-led efforts to develop high-resolution ocean and biogeochemical modeling and climate-scale prediction frameworks for the Northeast Pacific and other U.S. coastal waters.