The following article was originally published by the Daily Climate
A rare deadly lightning storm July 27 over Southern California’s Venice Beach raises questions about whether the drought-ravaged state faces new weather risks due to its changing climate.
A changing climate may alter Southern California’s weather patterns, making such “freak” occurrences more common.
One swimmer died after lightning strikes
The famed Los Angeles seaside community rarely sees lightning storms, but beachgoers rushed for cover when a thunderstorm struck at about 2:30 p.m. Four direct lightning strikes were reported, and bathers reported feeling their hair standing on end. A 20-year-old Los Angeles man was pulled from the water unconscious and later pronounced dead.
The same storm swept over Santa Catalina Island off Los Angeles about 90 minutes earlier, with lightning injuring a 57-year-old golfer and igniting two brush fires.
Climate change might enable extreme weather
Summer is the dry season in California, with any rain at all unlikely in July. Lightning is extremely unusual on the Southern California coast at any time because the weather is so heavily influenced by the ocean, which tends to stabilize the air, said Kevin Trenberth, senior scientist in climate analysis at the National Center for Atmospheric Research. It takes the meeting of warm, humid layers of air with colder, sometimes icy air to produce the build-up of electrical charges that lead to lightning.
“On the West Coast,” Trenberth said, “you don’t have the complex vertical structure and wind shear typically associated with lightning storms.”
But a changing climate may alter those weather patterns, making such “freak” occurrences more common. California’s historic drought, for example, has the potential to set up conditions for extreme weather. “With the drought, the contrast between the ocean and land is much greater than it otherwise would be,” said Trenberth. “It’s those contrasts that can help set up circulation and make the weather a little bit more vigorous than it otherwise would be.”
First twister in 64 years
The West Coast isn’t alone in freaky weather this week. A rare tornado smashed through Revere, Massachusetts, on Monday, wrecking about 65 homes and businesses and uprooting trees. The National Weather Service said it was the first twister in the area since 1950. Baseball-sized hail fell in Midland, Michigan.
A freak storm delivered hail and flash flooding to the United Kingdom, bringing trains and traffic to a standstill, according to the BBC. Meanwhile, Washington, D.C., saw bizarre weather of its own Monday: 24° C and pleasant in the normally hot, muggy capital.
Forty-five lightning strikes per second
Lightning occurs somewhere on Earth (or in the clouds) about 45 times per second, making it one of the most common extreme weather events. It is also one of the most deadly, with thousands killed by lightning strikes each year.
Scientists are studying the connection between climate change and the potential for increased lightning, but they have not arrived at any clear conclusions.
A Tel Aviv University researcher has predicted that for every one degree Celsius of warming, there will be approximately a 10-percent increase in lightning activity.
But Richard Blakeslee, a lightning expert with NASA’s Airborne Science Program, says that the space agency has not detected any change in lightning patterns in the United States that could be associated with climate change.
New satellite will map planet's lightning
The tools for such research will soon be improving. NASA’s next geostationary satellite, GOES-R, scheduled to launch in early 2016, will have a sophisticated new lightning-mapping instrument aboard. “We will be able to collect more data on lightning in the first two weeks than we’ve been able to gather in the whole 17 years of satellite monitoring of lightning,” Blakeslee said. One of the primary aims is to develop better forecasting, crucial to avoiding lightning deaths and injuries.
“Part of the issue [in the southern California storm] is because thunderstorms are so unusual, people aren’t watching for them,” said Blakeslee.