While the National Park Service is celebrating its 100 birthday today, its recent report on the impact of climate change on the Bay Area’s nine national parks suggests that the coast and its tremendous biodiversity are at risk.
In the highest emission scenario, sea levels could rise up to 39 inches by 2100, saturating one-fifth of the land around Stinson Beach and transforming many other low-elevation areas in the Golden Gate National Recreation Area and Point Reyes National Seashore.
Despite his grim projections, author Patrick Gonzalez, the principal climate change scientist for the National Park Service and a lead author for the Intergovernmental Panel on Climate Change, remains optimistic. “I would emphasize that climate change is not inevitable. It is really in our hands to reduce the carbon pollution that’s altering the national parks,” he said.
The report, which combined Mr. Gonzalez’s original analysis with a comprehensive review of all relevant studies to date, confirmed that human-caused climate changes have altered the parks, which are also vulnerable to further changes.
Most notably, the report showed that rising temperatures and sea levels are threatening the region’s flora and fauna. Within the nine parks, average annual temperature from 1950 to 2010 increased up to 3 to 5.6 degrees Fahrenheit; the climate change panel projects that temperatures will continue to rise.
These warmer temperatures heighten the likelihood of drought years, in which exceptional heat overlaps with low precipitation. For G.GN.R.A., 2014 was the driest year on record. That year was among the top 10 driest years for most of the other parks in the study.
While sea-level rise projections in the Bay Area align with global trends, approximately half of the seashore and G.G.N.R.A. shoreline are classified as highly vulnerable. The report cites the climate change panel’s most recent study, which “projected global sea level rise of [10 to 22 inches] for the lowest emissions scenario and [20 to 39 inches] for the highest emissions scenario by [the year] 2100.”
While shorelines with rock cliffs, steep slopes and low wave heights are more secure, much of the area lacks those attributes and is at risk for inundation.
For marine life, rising ocean levels and temperatures will have a significant impact. The report highlights critical habitat loss for harbor seals, northern elephant seals and the endangered western snowy plover; migration shifts northward for the migration of gray whales, coho salmon and steelhead; and complications for shellfish, corals and pteropods—or sea snails and sea slugs—due to ocean acidification.
The report’s findings help to summarize and corroborate the work of the region’s climate change scientists.
According to Grant Ballard, the chief science officer of conservation nonprofit Point Blue, the Bay Area is a good site to focus climate change research: the parks encourage and support science and, as a result, the region has a great deal of historic data. As opposed to short-term data, which can be distracting, this long-term body of information helps to identify climate trends.
Mr. Ballard also highlighted the importance of the report’s conclusion, which—in a turn toward optimism—explains the role the parks play in mitigating climate change. The area’s tidal marshes contain soil organic carbon—the main source of energy for soil microorganisms—at relatively high densities. Aboveground vegetation, especially coastal redwoods, in the nine parks stores an amount of carbon equivalent to the annual emissions of about 370,000 Americans, and recent trends show that this amount is increasing.
“The beautiful landscape that we have is performing all kinds of ecosystem services for us,” Mr. Ballard said. “It gives us a certain amount of resiliency that other places just don’t have. It’s naturally a very resilient and a well-buffered place.”