Forests and Climate Change

Forests and Climate Change

Source of global CO2 emissions by Sector. IPCC 2007

Source of global CO2 emissions by Sector. IPCC 2007

Climate change is driven by greenhouse gas emissions;  and forest loss and poor land management are responsible for up to twenty-five percent of annual global emissions—equal to the emissions from the entire global transportation sector. California is aggressively fighting climate change by reducing emissions across all sectors of its economy, but we live in a global society, and Climate Change does not stop at our borders. California Air Resources Board Chairwoman Mary Nichols argues that “without action to reduce emissions from the deforestation of tropical forests, we are missing one of the keys to mitigating climate change.”

Climate change is already affecting California.  As the state looks to avoid the worst impacts on its people, economy, and natural systems, it will need to support efforts to reduce emissions, in California and outside our own borders.

Human Communities: Heat and Drought

California is getting warmer. By 2050, California is likely to warm 2.7° F above 2000 averages, with summer temperatures rising the most. This means more frequent and extreme heat waves punishing central valley communities and at-risk people in our cities, challenging farmers, and taxing the state’s degraded energy infrastructure.

Weather patterns are changing, leading to increased water insecurity. The conditions behind the most recent drought have been linked to climate change and are more likely in the future; this will put added stress on a water system that is already over-allocated. One recent study indicates that by the year 2050 median California mountain snowpack present on April 1 could be one third less than in the past. The largest source of freshwater in the state, the sierra snowpack is responsible for filling many of the state’s water storage reservoirs. The California Department of Water Resources has made adapting to the new climate regime a key pillar of its updated Water Plan.

Sea Level Rise

California’s coastline, and its 32 million citizens living in coastal counties, are threatened by rising sea levels. The sea level along California’s coast has risen by 7 inches in the past century, and is projected to increase by as much as 55 inches by the end of this century under certain climate change scenarios. This would put an estimated 460,000 people at risk during major coastal floods, and endanger critical energy, water and transportation infrastructure. To put this in perspective, the current 100-year flood event (an event predicted to occur once every hundred years) could, under the worst climate change scenarios, become an annual event by the year 2050.


Every year, Californians produce $44.7 billion in revenue from agricultural crops like strawberries, almonds and citrus. The agricultural sector is a pillar of the state’s economy, and it will face serious stresses due to climate change. Increased drought and hotter temperatures will stress crops, limit what can be grown and when, and force farmers to change growing strategies or move locations.


Climate change is significantly increasing the state’s fire risk, through changes in temperature and snowmelt, as well as prolonged dry periods. Research has estimated that current warming trends will lead to a 58% – 128% increase in the number of fires by the year 2085. The area burned is expected to increase by between 57%-169% over that same period, depending on location. Wildfires threaten the state’s energy and transportation infrastructure, as well as communities, agriculture, and natural resources.

Species Loss

 Juvenile coho in a deep pool in Ellsworth Creek at The Nature Conservancy's Ellsworth Creek Preserve near Naselle, Washington. PHOTO CREDIT: ©Bridget BesawClimate change is rapidly altering the living conditions for California’s plants and animals, making adaptation difficult. This is exacerbated by the extent that land and aquatic systems are fractured by human development. One study shows that 83 percent of California 121 fish species are at high risk of extinction due to climate change, including the commercially valuable coho salmon and steelhead trout.

The state is one of the most biologically diverse places on earth, and those ecological systems are responsible for pollination, water management, soil health, and a host of other ecosystem services. They are also a key part of what makes the state such a wonderful place in which to live.  California must do all within its power, where ever it can, to stop the emissions of carbon pollution that are causing climate change while it makes  plans to respond to the risks already underway.

To read more about the impacts of climate change in California, read Our Changing Climate: Vulnerability and Adaptation to the Increasing Risks from climate change in California.