USA — The fossil record shows that wildfires started soon after the appearance of plants on land 420 million years ago! Wildfires have shaped plant communities and landscapes throughout time and several plant species have adapted to fire, needing smoke and heat to break their dormancy. However, wildfires also have negative effects, such as economic losses, destruction of property, soil erosion on slopes, and landslides.
You may have heard in the news that northern California is in a state of emergency due to wildfires and five states in the Western U.S. have reported 30 large fires. With so much at stake, what does science say about wildfire trends?
– According to the National Climate Assessment, reconstruction of fire history in the Southwestern U.S. shows climate outweighs other factors in determining the extension of burned area. From 1970-2003, warmer and drier conditions in the West have increased the burned area in mid-elevation conifer forests by 650 percent. – The National Interagency Fire Center has documented 72,000 fires per year in the United States since 1983. Nine of the 10 years with the largest acreage burned occurred since the year 2000, coinciding with many of the warmest years on record. – The West showed an increase in the number of large wildfires at a rate of nearly seven large fires per year from 1984-2011. The total burned area has increased by 216 square miles per year for the same time period. – The average annual fire suppression expenditures in the U.S. have more than doubled to $1.2 billion annually for the period 2001-2010, compared to $580 million in annual expenditures from 1991-2000. These expenditures represent only a fraction of the costs, since wildfires result in health care costs and loss of life, among others.
Learn how to protect your family before, during and after a wildfire and explore the figure below from EPA showing Wildfire Extent in the United States from 1983-2013.