What is happening?
- Wildfires occur naturally and help the forest ecosystem remain healthy.
- The frequency and severity of wildfires has rapidly increased since at least 1985 (see graphs below). There were 13% more wildfires globally in the year 2020 than in 2019.
Graphs with time on the horizontal axis and with the vertical axes showing the number of wildfires per year (left) and the number of acres burned per year (right; from UCSUSA, 2020).
- Fighting wildfires is very expensive. Between 2014 and 2018 the US government spent 2.4 billion dollars on fighting wildfires, more than twice the amount spent between 1994 and 1998.
- Widespread bushfires killed and displaced 3 billion animals in Australia in early 2020. Bushfires refer to wildfires in areas with lots of scrub vegetation. Pictured below is an image of the bushfires as well as a map showing their locations.
Image of a bushfire in Australia (left; from NYT 2020), and a map of the bushfire locations in the year 2020 (right; from BBC News 2020).
- The number of yearly wildfires in California doubled from 2019 to 2020, reaching over 8,200 separate fires. Overall, these fires burned more than 4 million acres of land. Pictured below is an image of one of the fires, and a map of wildfire locations in California.
Image of a wildfire in California (left; from NBC News 2020), and a map of wildfire locations in California in the year 2020 (right; from Cal Fire 2020).
- Wildfires also have a large impact on human health. It has been reported that over 300,000 people die prematurely every year due to wildfire smoke. As wildfires continue to increase, this number will only go up.
How is this related to climate?
- While wildfires are naturally occurring, climate change has altered the many factors that lead to wildfires.
- As average global temperatures increase, snow and ice melt sooner in the year than they do naturally. This causes the forest to remain drier for a longer period of time. A forest that is drier and hotter is far more susceptible to wildfires.
- Climate change and wildfires form a positive feedback loop. Wildfires destroy large carbon sinks and release copious amounts of carbon dioxide into the atmosphere. As climate change causes wildfires to increase, the carbon in the atmosphere increases, causing climate change to worsen in the long-term.
References and additional resources
- “Australia Fires: A Visual Guide to the Bushfire Crisis”, BBC News, 2020. Australia fires: A visual guide to the bushfire crisis – BBC News
- “Fires, Forests and the future: a Crisis Raging out of control?”, WWF, 2020. Fires, forests and the future: a crisis raging out of control? | WWF (panda.org)
- “InfoGraphic: Wildfires and Climate Change”, Union of Concerned Scientists, September 2020. Infographic: Wildfires and Climate Change | Union of Concerned Scientists (ucsusa.org)
- Kwai I., “The Australian Fires: Everything you need to Read”, The New York Times, 2020. The Australia Fires: Everything You Need to Read – The New York Times (nytimes.com)
- McKenzie D. et al., “Climate Change, Wildfire, and Conservation”, Society for Conservation Biology, 2004. The Society for Conservation Biology (wiley.com)
- Richwine M., “2020 Fire Season”, Cal Fire, 2020. 2020 Fire Season (ca.gov)
- Stelloh T., “California Exceeds 4 Million Acres Burned by Wildfires in 2020”, NBC News, 2020. California exceeds 4 million acres burned by wildfires in 2020 (nbcnews.com)
- Westerling A.L. et al., “Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity”, Science.org, 2006. Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity (science.org)