U.S. Wildfires

EXPLAINED IN 66 SECONDS

WHAT IT IS

Since 1970, the annual average number of wildfires larger than 1,000 acres has more than doubled in the western U.S. The typical wildfire season has also stretched by about two and a half months longer over that time. The main cause has been rising temperatures that have led to earlier snowmelt in the western U.S., which has led to drier conditions. These factors are helping drive an increase in the total area burned. Projections indicate that for every 1.8°F further rise in temperature — and the western U.S. could see average temperatures rise by up to 9°F by 2100 — there could be a quadrupling in the area burned each year in the western U.S..

WHY IT'S IMPORTANT

U.S. forests sucked up approximately 250 million metric tons of carbon in 2010, offsetting more than 15 percent of all of the nation’s carbon dioxide emissions. Wildfires threaten to turn forests from a carbon sink into a source of emissions by releasing that stored carbon into the atmosphere, something already happening in California. Wildfires also have serious health consequences. From 2002-13, fires in the western U.S. routinely caused air quality to be 5 to 15 times worse than normal in cities within 100 miles of fires. Increasing fires also mean increasing costs to fight them. The U.S. Forest Service and Department of the Interior together spend $3.5 billion a year to fight fires, three times what they spent in the 1990s, and a figure only expected to grow.

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