San Francisco Bay Area Marine Sanctuaries Project Localized Climate Change Impacts
Photo: Chad King, via sanctuarysimon.org
On Thursday, the California Academy of Sciences kicked off its Oceans Conference with a recently released report on the impacts of climate change on the Gulf of Farallones and Cordell Bank National Marine Sanctuaries. The impacts report is a first step towards a climate change action plan for these sanctuaries. The setting inside a museum with an aquarium was appropriate as fish are among the species that will be impacted by climate change. The Gulf of the Farallones is a 1,255-square-mile area made up of tidal flats, rocky intertidal areas, wetlands, subtidal reefs and coastal beaches. The sanctuary is home to thousands of seals and sea lions, and hosts great white sharks and the largest concentration of breeding seabirds in the continental U.S. The Cordell Bank Sanctuary is a 526 square mile area beyond the Gulf of the Farallones, 52 miles northwest, at the edge of the continental shelf. Endangered humpback whales, porpoises, albatross and marine species are found in these habitats.
The report provides the foundation of information needed to develop climate change action plans for these sanctuaries. The report is the outcome of eighteen months of collaboration among local experts from 16 organizations. The report - titled "Climate Change Impacts: Gulf of the Farallones and Cordell Bank National Marine Sanctuaries" - makes recommendations for future action for sanctuary management.
The report identified some key issues as well as some data gaps. Sea level rise is occurring at the mouth of San Francisco Bay. Ocean acidity levels are rising. Extreme weather events, which are becoming more likely, are causing coastal erosion.
Of perhaps most concern is the northern movement of some species. For example, gray whales, Humboldt squids and bottlenose dolphins all now travel much further north to find food. Sunburst anemones are also now extending into Northern waters. As climate change continues, this trend is expected to get worse.
In the future, the report projects more La Ninas than El Ninos. La Ninas are associated with strong upwelling in the ocean; El Ninos are associated with a lull in the cold upwelling conditions, which typically prevail in that area.
Upwelling is a process that involves wind driven motion of dense, cooler, and nutrient- rich water towards the surface, replacing the warmer, nutrient-depleted surface water. The increased availability in upwelling regions results in high levels of primary productivity and fish production. So upwelling is the key process that begins the food chain. Too much or too little wind can upset the process. Upwelling is projected to increase due to climate change which could be a good thing, as upwelling will cause some waters to get cooler and some fish, such as Coho salmon, prefer cooler waters. However, while upwelling is increasing, inland bays, such as Tomales Bay, are warming. This warming could counterbalance the cold upwelling forces.
In this manner, much of the data is inconclusive, and too broad to list specific impacts due to climate change. For example, the data shows that here has been a decline in rockfish at the sanctuaries, but it is unclear if this is associated with climate change.
After the presentation of the report in the Museum's planetarium, there was a panel of several of the report authors giving the public the opportunity to ask questions. One audience member asked about quantifying the economic impact of climate change impacts. Currently there is not a lot of detail in the economic projections. Pacific Institute's reports have some economic information in addition to climate change impacts but their reports do not address the topic of erosion.
The sanctuary administrators want to bridge the gaps between science, management and policy. They are committing to taking action and scientists and managers at the sanctuaries are already working together on next steps.
What are the next steps?
We need to devise policies that promote the ocean's resiliency, so that species can withstand/adapt to climate change. We need to protect valuable assets, including wetlands and buffers that protect the coasts. We need to employ best management practices with sediment reducing Total Maximum Daily Loads (TMDLs) etc.
Stay tuned on the NOAA website for further recommendations and updates.