Tornadoes Spinning Up Further East In US Consistent With Climate Change

[bluewave]

https://www.apnews.com/9ddb3deeec9a49d6a1349b78f1ca0f03

https://www.nature.com/articles/s41612-018-0048-2.epdf?author_access_token=PQZthaEqlkut62uLi4HlpNRgN0jAjWel9jnR3ZoTv0Ofpugx93Jq3uh7IKWsjvSCCm9cT6oavbBDxy4CNfmgPbnVGCtRW0GfAXKcI3DSQ1vbeVbyw-jzqriwQAlEDMNsLcaDsYkvTU-SaxpOcafW-Q%3D%3D

WASHINGTON (AP) — Over the past few decades tornadoes have been shifting — decreasing in Oklahoma, Texas and Kansas but spinning up more in states along the Mississippi River and farther east, a new study shows. Scientists aren’t quite certain why.

Tornado activity is increasing most in Mississippi, Arkansas, Tennessee, Louisiana, Alabama, Kentucky, Missouri, Illinois, Indiana, Wisconsin, Iowa and parts of Ohio and Michigan, according to a study in Wednesday’s journal Climate and Atmospheric Science. There has been a slight decrease in the Great Plains, with the biggest drop in central and eastern Texas. Even with the decline, Texas still gets the most tornadoes of any state.

Why is this happening?

“We don’t know,” Gensini said. “This is super consistent with climate change.”

As the Great Plains dry out, there’s less moisture to have the type of storms that spawn tornadoes, Gensini said. Tornadoes form along the “dry line” where there are more thunderstorms because there’s dry air to the west and moist air from the Gulf of Mexico to the east.

That dry line is moving east.

“This is what you would expect in a climate change scenario, we just have no way of confirming it at the moment,” Gensini said.

Gensini said unless there are specific detailed studies, he and others cannot say this is caused by global warming, just that it looks like what is expected.

Pennsylvania State University meteorology professor Paul Markowski, who wasn’t part of the research, praised the study as careful and well done.

 

 

 

[FPizz]

2 hours ago, bluewave said:

https://www.apnews.com/9ddb3deeec9a49d6a1349b78f1ca0f03

https://www.nature.com/articles/s41612-018-0048-2.epdf?author_access_token=PQZthaEqlkut62uLi4HlpNRgN0jAjWel9jnR3ZoTv0Ofpugx93Jq3uh7IKWsjvSCCm9cT6oavbBDxy4CNfmgPbnVGCtRW0GfAXKcI3DSQ1vbeVbyw-jzqriwQAlEDMNsLcaDsYkvTU-SaxpOcafW-Q%3D%3D

WASHINGTON (AP) — Over the past few decades tornadoes have been shifting — decreasing in Oklahoma, Texas and Kansas but spinning up more in states along the Mississippi River and farther east, a new study shows. Scientists aren’t quite certain why.

Tornado activity is increasing most in Mississippi, Arkansas, Tennessee, Louisiana, Alabama, Kentucky, Missouri, Illinois, Indiana, Wisconsin, Iowa and parts of Ohio and Michigan, according to a study in Wednesday’s journal Climate and Atmospheric Science. There has been a slight decrease in the Great Plains, with the biggest drop in central and eastern Texas. Even with the decline, Texas still gets the most tornadoes of any state.

Why is this happening?

“We don’t know,” Gensini said. “This is super consistent with climate change.”

As the Great Plains dry out, there’s less moisture to have the type of storms that spawn tornadoes, Gensini said. Tornadoes form along the “dry line” where there are more thunderstorms because there’s dry air to the west and moist air from the Gulf of Mexico to the east.

That dry line is moving east.

“This is what you would expect in a climate change scenario, we just have no way of confirming it at the moment,” Gensini said.

Gensini said unless there are specific detailed studies, he and others cannot say this is caused by global warming, just that it looks like what is expected.

Pennsylvania State University meteorology professor Paul Markowski, who wasn’t part of the research, praised the study as careful and well done.

 

 

 

Interesting.  Hasn't the trend been somewhat flat to slightly downward over the past 100 years or so for overall tornado's per year?  So maybe slightly less to flat in #, but more spread out?  I didn't read the whole article, but does it include radar indicated tornado's or actual confirmed one's?  As we see here in the NE, many times radar indicates a tor but there wasn't actually one that occurred. 

 

 

[bluewave]

51 minutes ago, frankdp23 said:

Interesting.  Hasn't the trend been somewhat flat to slightly downward over the past 100 years or so for overall tornado's per year?  So maybe slightly less to flat in #, but more spread out?  I didn't read the whole article, but does it include radar indicated tornado's or actual confirmed one's?  As we see here in the NE, many times radar indicates a tor but there wasn't actually one that occurred. 

 

 

The linked full paper has a more detailed  explanation than the AP article. The Capital Weather Gang explored the methodology of the authors.

https://www.washingtonpost.com/weather/2018/10/17/us-tornado-hot-spots-are-shifting-plains-midwest-southeast-study-finds/?utm_term=.47605fd715db

The authors used a metric known as the Significant tornado parameter (STP) to approximate tornado activity over the years in their study (1979-2017). It is a complicated index of twister ingredients that measures the potential potency of a tornado environment.

“[We found] a robust downward trend in the annual accumulation of STP across the central and southern Great Plains,” the study says. “Meanwhile, a robust upward trend is found in portions of the Southeast, Midwest, and Northeast.”

Gensini and Brooks compare findings using STP to actual tornado reports to validate their findings. There are many similarities plus a few conflicts. One advantage that STP has over actual reports is that it is not affected by the rise in weather spotters and better detection capabilities that have pushed up the number of weak tornadoes observed in recent decades.

The study found that in a majority of locations, agreement between STP environments and reporting was strong. The mid-South, in particular, has shown a significant increase in STP environments and tornado confirmations

 

 

 

 

 

 

[Hoosier]

2 hours ago, frankdp23 said:

Interesting.  Hasn't the trend been somewhat flat to slightly downward over the past 100 years or so for overall tornado's per year?  So maybe slightly less to flat in #, but more spread out?  I didn't read the whole article, but does it include radar indicated tornado's or actual confirmed one's?  As we see here in the NE, many times radar indicates a tor but there wasn't actually one that occurred. 

 

 

The flattening/decreasing trend over the decades has been for the stronger tornadoes, not all tornadoes. 

[WarmNose]

I stopped reading after this asinine little “factoid”

Why is this happening?

 “We don’t know,” Gensini said. “This is super consistent with climate change.”

[bdgwx]

On 10/21/2018 at 4:58 PM, WarmNose said:

I stopped reading after this asinine little “factoid”

Why is this happening?

 “We don’t know,” Gensini said. “This is super consistent with climate change.”

The following quote clears up Gensini's statements above.

“This is what you would expect in a climate change scenario, we just have no way of confirming it at the moment,”

He's saying they don't know why STP values are increasing/decreasing the way they are, but the effect is consistent with the expectations of climate change. Being consistent with an expectation doesn't validate the hypothesis behind the expectation though. More (and different kinds) of research need to be done to definitively link the cause with the effect.