The Nicholls Fire, which started burning in Kern County on Friday, July 11th has quickly grown to over 1,600 acres as of July 15th. Even though firefighters have been able to get the fire to 80% containment over the course of these five days, the fire is an example of the rapid increase in large Sierra wildfires which can affect the entire state. We all know that forests store carbon and act as one of our most effective buffers against climate change. According to a 2012 USGS study, forests account for almost seventy percent of the total carbon storage in the Western U.S. So what happens when our biggest carbon storage burns and becomes a major greenhouse gas emitter?
Earlier this year the journal Environmental Science & Technology published a study indicating that California will experience more large fires, and that with that increase in wildfire activity comes a significant increase in fire-generated greenhouse gas emissions.
Modeling done for the study suggests that because California forests will experience larger fires, wildfire emissions will increase by 24 percent over 1961-1990 values in the next 30 years, and that in the next 70 years they will increase by more than 50 percent. That means that efforts being made in California to reduce vehicle emissions, curb industrial emissions, and invest in clean energy could go up in smoke – literally.
The study found that by the year 2085, emissions from wildfires are projected to be equal to the annual emissions of about one fifth of all of the cars currently registered in California. This is a trend that has already started. Early estimates indicate that the 2013 Rim Fire alone released roughly the same amount of greenhouse gasses as were released during the entire year in 1970. Even if we were to be successful in reducing the number of cars, or increasing the number of clean burning vehicles on our roads, one fire season can dump us right back to where we started.
Something can be done now to alter this trend. Modeling done by the Forest Foundation on four fires in the Sierra Nevada showed that emissions from wildfires can be reduced by reducing the amount of overgrown vegetation in Sierra forests. The four fires studied released a total of 38 million metric tons of greenhouse gasses in to the atmosphere, or the equivalent of “adding an estimated 7 million more cars onto California’s highways for one year. Stated another way, this means 50 percent of all cars in California would have to be locked in a garage for one year to make up for the climate change impact of these four wildfires.”
Each of these fires burned through areas that were severely overgrown. Where these fires burned the forest averaged 350 trees per acre, when naturally there should have only been 50 to 60. Had that overgrowth been reduced to a more natural forest condition, the emissions could have been lowered from 46.2 tons per acre to 12 tons per acre.
Air pollution managers know that wildfires are a contributor to emissions. However, the increasing trend in the size and frequency of wildfires in the Sierra will become a larger problem and may be detrimental to efforts being made throughout California to lessen the impacts of climate change. All of the public dollars spent on reducing greenhouse gas emissions in urban areas may be compromised if our forests –the best buffer that we have against climate change in the Western U.S. – are reduced to ash and smoke.
Improving forest health by increasing the pace and scale of forest restoration needs to be one of the key tools in the toolbox for addressing climate change. We can reduce the amount of cars on the road, or decrease the amount of emissions released by industry, but all of those efforts will be less effective if California’s largest carbon storage resource continues to erupt in flames.
The Sierra Nevada Conservancy has invested almost $11 million to improve the health of forests in the Sierra Nevada, but there is still a long way to go. If we expect our Sierra forests to function as a buffer to climate change, storing carbon released by our cars and businesses, we must act now to reduce the size and severity of wildfires.