Vulnerability to climate change of hypersaline salt marshes in the Northern Gulf of California

• We review existing scientific information on climate change impacts for salt marshes.
• We examine possible effects for wetlands in the Northern Gulf of California, Mexico.
• Marshes are susceptible to the synergistic and cumulative effects of climate change.
• Uncertainty and data gaps preclude detailed projections of climate effects.
• Existing data can be used to design management actions that consider uncertainty.

The ecosystem functions and environmental services provided by coastal wetlands are threatened by climate change and other anthropogenic impacts. Assessing the degree of vulnerability and the nature and extent of probable impacts of climate change on coastal wetlands is necessary to develop adaptation strategies. Here we review and synthesize existing scientific information to examine climate change impacts on physical and biotic processes of hypersaline salt marshes in the Northern Gulf of California, Mexico. In this region, negative estuaries provide nursery and refuge for migratory species and sustain important fisheries. We found marshes in the Northern Gulf may be susceptible to the effects increased CO2, sea-level rise, storm frequency and intensity, changes in ambient temperature, and ocean physical changes, including elevated sea temperature, and acidification. The responses of coastal marshes to these climate change effects will likely be interactive and hard to predict; climatic interannual variability (i.e. El Niño-Southern Oscillation) will play an important role in determining the strength and directionality of the impacts. Given the uncertainty of climate change effects, it will be important to continue ongoing monitoring programs and implement new ones that help separate natural variability from the effects of climate change. Management actions and adaptation plans will be needed that consider uncertainty, are flexible, and encourage ongoing learning. Our study is a first step toward understanding vulnerability of coastal wetlands in the Northern Gulf of California to climate change.