New study suggests severe thunderstorms will become more common
By Summit Voice
SUMMIT COUNTY — Global warming could result in fewer but more intense thunderstorms, with a 10 percent increase in lightning activity for every 1 degree Celsius of warming, according to a new study by scientists at Tel Aviv University.
The increase in more severe storms could up the chances for flash floods, wildfires and even damage to power infrastructure, according to Professor Colin Price, head of the university’s Department of Geophysics, Atmospheric and Planetary Sciences.
The researchers tested their climate models in real world conditions in Africa and the Amazon, and regions where climate change occurs naturally, such as Indonesia and Southeast Asia, where El Niño cyclically changes the atmosphere.
Price said the the El Niño phenomenon is an optimal tool for measuring the impact of climate change on storms because the climate oscillates radically between years, while everything else in the environment remains constant.
“During El Nino years, which occur in the Pacific Ocean or Basin, Southeast Asia gets warmer and drier. There are fewer thunderstorms, but we found fifty percent more lightning activity,” Price said. Typically, he says,we would expect drier conditions to produce less lightning. However, researchers also found that while there were fewer thunderstorms, the ones that did occur were more intense.
The research is part of an ongoing effort to determine how climate change will affect the world’s lightning and thunderstorm patterns.
An increase in lightning activity will have particular impact in areas that become warmer and drier as global warming progresses, including the Mediterranean and the Southern United States, according to the 2007 United Nations report on climate change.
The first step in the study was to assess how accurate;y the models can predict the frequency and severity of thunderstorms and lightning in today’s environment. Then, the researchers input changes to the model atmosphere, including the amount of carbon dioxide in the atmosphere (a major cause of global warming) to see how storms are impacted.
An increase in lightning and intense thunderstorms can have severe implications for the environment, Price said. More frequent and intense wildfires could result in parts of the US, such as the Rockies, in which many fires are started by lightning. A drier environment could also lead fires to spread more widely and quickly, making them more devastating than ever before. These fires would also release far more smoke into the air than before.
Researchers predict fewer but more intense rainstorms in other regions, a change that could result in flash-flooding, Price said. In Italy and Spain, heavier storms are already causing increased run-off to rivers and the sea, and a lack of water being retained in groundwater and lakes. The same is true in the Middle East, where small periods of intense rain are threatening already scarce water resources.
This research has been reported in the Journal of Geophysical Research and Atmospheric Research, and has been presented at the International Conference on Lightning Protection.