Imagine that you have been transported 100 years into the future. Look around. What do you see? The changes that are already beginning to occur within our parks due to climate change can serve as indicators of the future will we have.
The diverse and sensitive plants and animals adapted to the coastal environment at Golden Gate act as sentinels of global change. Our park's proximity to the coast provides us with key insight into our world's future. This is because the ocean regulates the earth's temperatures and moves heat around the planet, much like your heart circulates blood in your body. As the heart of the climate’s circulatory system, the ocean maintains the earth’s temperatures. But when we burn fossil fuels, we put a lot of stress on the ocean, damaging its ability to keep the climate stable. Today, the ocean absorbs over 90% of the added atmospheric heat associated with fossil fuel emissions. As a result of this stress, sometimes the ocean pumps too much heat and moisture throughout the system, sometimes too little. This is why there are differential effects of climate change in different parts of the world.
Golden Gate and the Bay Area is known for having many micro-climates and species with limited ranges, so we will be subjected to various effects. Rapidly changing climate patterns are threatening rare species that exist no place else. Some may not be able to adapt fast enough for the changing climate. Sea level is rising and the coast is eroding. In addition, the high concentration of CO2 in the atmosphere is dissolving in the ocean, making it more acidic, and affecting marine life critical to the coastal food chain.
Here are the most likely changes that Golden Gate will experience in the coming decades:
Atmospheric Rivers - Climate models suggest that Golden Gate will be exposed to substantial warming and a slight increase in precipitation. Rainstorms will become more intense but less frequent due to an increase in streams of moisture in the sky called "atmospheric rivers." In other words, California may experience weather whiplash as it oscillates between wet and dry extremes.
Drought - Even if precipitation increases, we are still at risk of drought. This is because hotter temperatures will lead to an increase in evaporation and aridity as water availability decreases.
Wildfire - As summer drought conditions increase, so does the risk of wildfire. Under a high emissions scenario, climate change may increase potential burned area 50% to 100% in the southern parts of Golden Gate by 2085.
Sea Level Rise - Tidal records at Crissy Field show a rise of about 0.2 meters (8 inches) in the last 100 years. This rate of rise is two to ten times faster than in the previous 5000 years, and the rate is increasing. Even a small rise in sea level can flood and erode broad coastal areas.
Loss of Species - Warming water temperatures may contribute to the loss of coho salmon, steelhead, and tidewater goby from our park. Gray whales may avoid Golden Gate's coast as temperatures rise. Climate change threatens endangered species, like the San Franciscan garter snake and the western snowy plover, with extinction.
San Francisco Bay Salinity - The bay may become saltier as rising seas push saltwater inland. Additionally, warmer winter temperatures in the Sierra will decrease winter snowpack and reduce freshwater inflows into the San Francisco Bay.
Ocean Current Changes - Climate change may intensify onshore winds and increase upwelling along Golden Gate's coast. The upwelling would increase nutrient inputs to surface waters, reduce oxygen levels, and disrupt food webs. It can also influence ocean acidification.
Increasing temperatures - Hotter weather will dry out habitats, leading to more drought stress on local plants, including the iconic redwoods of Muir Woods.