Multi-Stressor Observations and Modeling to Build Understanding of and Resilience to the Coastal Impacts of Climate Change

Multiple stressors are affecting the Pacific Northwest (PNW) coastal ocean, including harmful algal blooms (HABs), ocean acidification, marine heatwaves, and hypoxia (low oxygen). While these conditions or events are tied to seasonal cycles such as upwelling periods and multiyear cycles such as El Niño/La Niña, they are becoming increasingly frequent and intense. Additionally, they can have devastating impacts on ecosystem health and human wellbeing, shutting down fisheries, stifling the local economy, threatening food security, and inhibiting cultural practices. For example, increasing ocean acidification has affected shellfish growers’ capability to secure reliable product. In 2015, a HAB associated with a marine heatwave shut down crab fisheries from Alaska to Baja for commercial and tribal fishers (McCabe et al., 2016), a closure so impactful that the US Congress included the Fishery Disaster Relief Program for Tribal Fisheries in the Budget Act of 2018. And, an unpredicted hypoxia event in 2015 resulted in the Quinault Indian Nation pulling up crab pots with dead crab. Regional projections indicate increases in warming, ocean acidification, and hypoxia by the end of the century (Siedlecki et al., 2021), so solutions are needed. The challenge of multi-stressor impacts can be addressed by engaging a variety of partners to collect multi-variable observing and forecast data while increasing both scientific knowledge and application of data and information to real-world needs. The Northwest Association of Networked Ocean Observing Systems (NANOOS, http://www.nanoos. org/) helps sustain long-term observations and forecast models to help communities adapt to and plan for variable and changing ocean conditions, thus increasing resilience. NANOOS is the PNW regional coastal ocean observing system of the US Integrated Ocean Observing System (IOOS). It was recently designated a nexus organization for the UN Decade of Ocean Science for Sustainable Development because of its work to sustain and integrate ocean observations and modeling to produce publicly accessible regional data products that help diverse coastal communities ensure safety, build economic resilience, and increase understanding of the coastal ocean. NANOOS, in collaboration with regional partners, provides observations of temperature, salinity, oxygen, chlorophyll, carbon dioxide, pH, and HABs from buoy assets off the PNW coast (Figure 1). These observations also support several models such as LiveOcean, which provides 72-hour projections of ocean variables such as temperature, salinity, Multi-Stressor Observations and Modeling to Build Understanding of and Resilience to the Coastal Impacts of Climate Change