Expect 50 Percent More Lightning in a Warmer World

Americans should prepare to see more searing flashes in the sky in coming decades, say scientists, as the warming atmosphere drives up the number of lightning strikes.

The association between more heat energy in the atmosphere and the frequency of lightning bolts has been studied for a while. Past research suggests that for every uptick of 1 degree Celsius, there could be an increase in lightning of anywhere from 5 to 100 percent. But a team led by David Romps of the University of California, Berkeley, believe they've nailed down a more exact range: According to their new study in Science, there will be 12 percent more lightning in the U.S. for every elevation of 1 degree Celsius (with a 5 percent margin of error).

That might not sound like a big deal, but with the way the planet's heating up it could become one. We might already be seeing more thunderous zaps than our great grandparents: The atmosphere is nearly 1 degrees Celsius warmer than it was in the late 1800s. And if the global thermostat continues to jack up the temperature—recall that 2012 was the most sweltering year since records began in 1895—strikes could rain down furiously. Romps' crew says it's reasonable to expect a 50 percent rise in strikes through the rest of the century.

For folks who fear going up like a Roman candle anytime a storm rolls in, that can't be comforting news. But the most significant impacts of more lightning will be on the environment, such as bad breakouts of wildfires. The researchers write:

Because lightning is the primary trigger for wildfires, and generates nitrogen oxides that impact atmospheric content, the method Romps et al. developed has important implications for understanding future changes to wildfire frequency and atmospheric chemistry.