Severe Weather

Severe weather is the encompassing term for damaging thunderstorms and tornadoes. A warming world provides more energy for these severe local storms because of a warmer, more moist environment. But the behavior of shear in a warming world is still uncertain, and shear is necessary for tornado formation. While it’s still unclear how exactly climate change is impacting tornadoes, there are a few things the research is showing.

The long-term tornado record indicates that there has been an increasing variability in the number of tornadoes from year to year in the United States, with an overall trend toward fewer days with tornadoes per year but more tornadoes on the days in which they do occur (outbreak days). There is also preliminary evidence that the tornado season is starting earlier in the year in some parts of the country.

Resources for covering severe weather:

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Billion-Dollar Disasters of 2019

2019 marks the fifth straight year with at least ten U.S. billion-dollar weather and climate disasters—showing the increasing cost of extreme weather as the climate warms.

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Extreme Weather 101: Tornadoes

Is it possible to see a human imprint on the development of tornadoes? In Extreme Weather 101, we hear from scientist Deke Arndt and meteorologist Dan Satterfield on efforts to see whether there is any connection between twisters and a climate influenced by greenhouse gas emissions.

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Tell Me Why: Questions Swirl Around Climate & Tornadoes

Does a warming world affect the formation of tornadoes? The answer is one that scientists and researchers are trying to ascertain. In this edition of Tell Me Why, climate scientist Deke Arndt explains why questions continue to swirl around any kind of connection between climate change and tornadoes.

Watch on Climate Central