Summary of prior award and continuation request: recent analysis of initialized decadal predictions show that changes in marine ecosystem habitats are potentially predictable on multi-year to…

The University of California San Diego's Scripps Institution of Oceanography was awarded a $749,367 Cooperative Agreement from the National Oceanic and Atmospheric Administration (NOAA) under the Climate and Atmospheric Research program (CFDA 11.431). The project aims to improve understanding of the processes driving oxygen (O2) variability and change in the Northeastern Pacific, which is critical for enhancing ecosystem habitat predictions in Large Marine Ecosystems like the California Current and Gulf of Alaska. The research will leverage model simulations, observational data, and autonomous measurements to identify the contributions of global, regional, and mesoscale processes in modulating O2 variability and the development of metabolic extreme events. The 3-year project will provide insights to inform NOAA's climate ecosystem and fisheries modeling efforts, as well as guide the observing system's readiness to monitor marine ecosystem extremes in the region.

Summary of prior award and continuation request: recent analysis of initialized decadal predictions show that changes in marine ecosystem habitats are potentially predictable on multi-year to decadal timescales. Due to its dominant role in defining metabolic rates, oxygen (O2) explains most of this multi-year habitat predictability in the northeastern pacific (NEP) large marine ecosystems (LMES) such as the california current (CC) and gulf of alaska (GOA). However, the processes driving O2 variability and change explaining its predictability are not well understood. Developing a fundamental understanding of these processes is central to improving ecosystem habitat predictions and model predictive skill. O2 variability and change is driven by physical and biogeochemical processes that span across a range of temporal and spatial scales from global external drivers and basin scale variability to mesoscale eddies and biogeochemical feedbacks. We propose an interdisciplinary approach leveraging recently developed coupled and forced model simulations along observational products and autonomous measurements to address these gaps. Specifically, we aim to identify: I) the contribution and underlying mechanisms governing global, externally forced changes in O2 in the NEP, II) how mesoscale processes influence the transient and mean O2 structure and variability in the NEP LMES, and III) how interactions across scales and ecosystem drivers modulate O2 variability and synergistic extremes across ecosystem stressors. To achieve these objectives, we first propose to analyze outputs from the community earth system model (CESM) large ensemble and single forcing experiments designed to isolate the effects of external greenhouse gas (GHG), aerosol impacts, and internally generated variability on the earth system. Next, we will also assess eddy transient and mean impacts on O2 transport in a global eddy resolving hindcast simulation of CESM and a regional hindcast of the NOAA gfdl MOM6 model for the NEP (MOM6 NEP) and observations from BCG argo floats in the NEP, and compare these to a 1 analog simulation of CESM to assess the role of model resolution in representing eddy phenomena. Finally, we aim to synthesize our understanding of how these processes interact from global to regional scales to modulate O2 variability and the development of metabolic extreme events in the NEP. Identifying the role, mechanisms, and interactions between global to mesoscale drivers of O2 variability and change is critical for NOAA climate ecosystem and fisheries initiatives (CEFI) mission to build reliable ecosystem predictions in key productive LMES of the NEP. Our proposed work is highly aligned with many of this calls priorities by assessing the physical and biogeochemical drivers underlying ecosystem stressors and their synergistic occurrence, and identifying interactions across processes, scales, and stressors. Insights from our process understanding using the single forcing and eddy resolving configurations of CESM, MOM6 NEP and BGC argo observations will explicitly inform noaas modeling efforts by identifying missing processes and biogeochemical feedbacks in current models to guide model forcing, resolution, and parameterization needs for on-going global and regional model prediction efforts at NOAA. Our work also has direct implications for informing the current readiness of the NOAA observing system (e.g., BGC argo) in monitoring marine ecosystem extreme events and guiding long-term observing strategies and deployments in the NEP.