Global lightning?Here's another unexpected possible impact of climate change: More lightning strikes. In a paper published in the journal Science, UC Berkeley researchers look at predictions of precipitation and cloud buoyancy from 11 different climate models. They conclude that their combined effect will generate a 50% increase in lightning strikes across the United States during the 21st century, and this because of the warmer temperatures caused by global warming.
The principle is a bit similar to how hurricanes are predicted to be, on average, stronger and more frequent because of global warming. Heat, and the water vapor that results from increased heat, as fuel for hurricanes, and in the same way, they are fuel for lightning:
“With warming, thunderstorms become more explosive,” said David Romps, an assistant professor of earth and planetary science and a faculty scientist at Lawrence Berkeley National Laboratory. “This has to do with water vapor, which is the fuel for explosive deep convection in the atmosphere. Warming causes there to be more water vapor in the atmosphere, and if you have more fuel lying around, when you get ignition, it can go big time.”
This might not seem too bad at first glance, but more lightning strikes means more people injured and killed (estimates currently range from hundreds to nearly a thousand per year in the US), and more wildfires, since about 50% of wildfires are started by lightning. This is a compounding problem because global warming also tends to affect drought patterns and some areas (like the US West right now) might be more affected, and more vulnerable to wildfires.
Here's a very cool map of lightning strikes over the United States in 2011, compiled by UC Berkeley:
Via UC Berkeley