WASHINGTON (CBSDC) – Global warming will cause a 50 percent increase the number of lightning strikes in the United States by 2100, according to a new study.

Researchers found a 12 percent increase in lighting activity for every 1.8 degrees Fahrenheit of warming in the atmosphere.

The study also pointed out that because lightning often triggers wildfires, the increase of lightning strikes could mean more fire damage.

“This is yet another noticeable change to climate and weather in the U.S. if we stay on our current emissions trajectory,” David Romps, an atmospheric scientist at the University of California, Berkeley, and the study’s lead author, told Live Science.

The only problem is that you can’t predict when or where lighting activity will intensify.

“At this point, we don’t know where the increase will take place, or when it will take place,” Romps added.  Figuring this out would require a more detailed analysis of the data.”

In order to determine future lightning patters, Romps and his team looked for factors that control the timing and location of lightning in the present day.  They then estimated how these factors would change as global warming altered climate and weather.

The researchers discovered a new combination of factors that can predict 77 percent of the geographic and time patters seen in U.S. lightning strikes. The first factor was precipitation.  The second factor was convective available potential energy, or CAPE.  CAPE is a measure of the atmosphere’s potential for creating towering clouds.

They were surprised by how well these factors predicted lightning strikes.

“This success gave us confidence to say this is a metric for what lightning would be doing in the future,” Romps told Live Science.

The researchers used 11 climate models along with CAPE to calculate what is expected to happen with global warming.

The average of all the models was a 50 percent increase in lightning activity by 2100.

The researchers noted that if the climate changes then the factors that control lightning today may be different in the future so their prediction may be off. “Their approach does a reasonable job of reproducing current patterns and time variations of lightning in the U.S.,” Anthony Del Genio, a research physical scientist at NASA’s Goddard Institute for Space Studies in New York, said. “The question is whether something that works in the current climate is also applicable to a climate change.” Del Genio was not involved in the study.

“The bottom line is that this is a plausible metric to propose for lightning, but it remains to be seen whether it gives realistic projections for the future,” Del Genio added.  “Other proposed metrics are equally likely to do a good job.”


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