Climate variability leads to more intense thunderstorms • Earth.com

Climate variability leads to more intense thunderstorms In a new study by Texas A&M University, experts report that large thunderstorms in the southern Great Plains of the United States have increased in frequency and intensity. The researchers found that these changes are linked to climate variability.

“Thunderstorms in the southern Great Plains of United States are among the strongest on Earth and have increased in intensity and frequency in recent years, ”the researchers explained.

“Assessing changes in storm characteristics under different climate scenarios, however, remains very uncertain due to the limitations of the physics of climate models. “

The current study focused on isotopes from stalactites in Texas caves dating back between 30,000 and 50,000 years. The researchers analyzed the oxygen isotopes contained in the stalactites to identify trends from past thunderstorms.

“Storm regimes shift from weakly to strongly organized over millennial time scales and coincide with well-known abrupt climate changes during the last ice age,” the study’s authors found.

“Modern synoptic analysis suggests that the organization of thunderstorms in the southern Great Plains is strongly related to changes in large-scale wind and humidity patterns.”

Understanding these changes will not only help reconstruct past storm patterns, experts say, but will also help predict mid-latitude patterns that will emerge in decades to come.

“Proxy recordings are available in the southern great plains in caves,” study co-author Christopher Maupin said. “There are probably thousands of caves in the southern Great Plains and southern Texas. Why has there not been more research in these areas? Cave deposits are so promising as a proxy.

Study co-author Courtney Schumacher said scientists understand modern precipitation models. “However, we don’t know what will happen in the future, and this work will help predict storm trends in the future,” Schumacher said. Climate variability leads to more intense thunderstorms

“If we can run a climate model for the past that is consistent with the cave records, and run that same model in the future, we can have more confidence in its findings if it matches the cave records than if they were. are not. On two models, if one really matches the isotopes of the cave, you can trust that one to understand the distribution of storms in the future. “

“There are some really important questions about what has happened in the past regarding the large weather events we experience through mesoscale convective systems (large storms) versus non-mesoscale things (small storms).”

“We get so much precipitation from really big storms, and the model grids can’t capture big weather events because the grids themselves are so big. Paleoclimatology helps organize past events to develop an indirect record of how they react to average climate. “

Schumacher noted that large storms that cover hundreds of miles provide about 50 to 80 percent of rainfall in Texas.

“These thunderstorms are so big that even though most of the rain occurs in Oklahoma, the rain in Texas will still carry the isotopic signature of these huge storms,” said Maupin.

“You take fingerprints from these systems wherever they are, and they don’t need to be super-localized to be recognized. Large storms cause depleted isotope signatures. You cannot explain the variability of stalactites by temperature changes alone.

The study is published in the journal Geosciences of nature.

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Through Chrissy sexton, Terre.com Editor-in-chief