Warming climate intensifies summer drought in parts of U.S., study finds

midwest
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Climate change is amplifying the intensity and likelihood of heatwaves during severe droughts in the southern plains and southwest United States, according to a new study by a University of Arkansas researcher.

Linyin Cheng, assistant professor of geosciences, used data from the National Center for Atmospheric Research's Community Earth System Model to study summer droughts that occurred both before and after the Industrial Revolution. Cheng and colleagues from the National Oceanic and Atmospheric Administration and universities in China and Colorado ran simulations to assess how, and by how much, human-induced change affects summer heatwaves in the contiguous United States. The study was published in the Journal of Climate.

The researchers found that in places with low moisture in the soil, such as the southern plains and southwest, brought about by climate change led to an increased "coupling" of land and atmosphere, which further increased the severity of heatwaves. In places with more moisture in the soil, such as the northeast, they found no appreciable coupling and therefore no contribution to heatwave intensification.

"Our analysis of climate simulation finds that summertime drought-heatwave relationships change significantly over the southern and southwest U.S. due to man-made climate change since the late 19th century," said Cheng. "By contrast, the drought- relationship over northern U.S regions undergoes little change in the warmed climate."

The findings raise the idea of a self-reinforcing climate loop: as a region's climate becomes more arid due to , droughts become hotter, further reducing soil moisture.

"Overall, these results indicate that strengthened land-atmosphere feedback is a significant physical driver for increasing occurrences of drought-related extreme heatwaves, particularly over the semi-arid and arid regions of the United States," the report states.


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Semi-arid land in China has expanded in recent decades and probably will continue to expand

More information: Linyin Cheng et al. Physical Understanding of Human-Induced Changes in U.S. Hot Droughts Using Equilibrium Climate Simulations, Journal of Climate (2019). DOI: 10.1175/JCLI-D-18-0611.1
Journal information: Journal of Climate

Citation: Warming climate intensifies summer drought in parts of U.S., study finds (2019, July 15) retrieved 22 August 2019 from https://phys.org/news/2019-07-climate-summer-drought.html
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Jul 15, 2019
Apparently the author has not been up to speed on the latest weather conditions crashing in from the gulf.

Jul 15, 2019
Another display of the constant pretense of caring about "climate change".
Those who claim to care about "climate change", generally, couldn't care less.
Climate is not changing, it is only the weather that is becoming aberrant. And it is chemtrails, doping the atmosphere with weather modification chemicals, leaving non dissipating vapor lanes that stretch from horizon to horizon and can last for an hour or more, that are changing the weather. Those who really care would not ignore anything in their interest in solving the problem. But those who pretend to care about the behavior of the atmosphere won't discuss chemtrails, they won't examine facts about them, they won't even say the word!
Interesting to note, though,they found it necessary to start this article with a picture of massive chemtrailing. Perhaps they are admitting it will soon no longer be possible to deny chemtrails and Phys Org wants to ease into the subject.

Jul 15, 2019
Five years ago, the greenloons told us "the Great Lakes are drying up!" In the last two years, water levels have been at their highest ever. No one sane puts one cent of investment into the prognostications of environmentalists because their 50 year record of doomsaying is abjectly wrong.

Jul 16, 2019
So in the spring they get floods, and in the summer they get droughts.

Butttbutttbuttttheresnoglobalwarming /s

What a bunch of dickheads. Were you born stupid or did you have to practice?

Jul 16, 2019
Thorium
No one sane puts one cent of investment into the prognostications of environmentalists
Predicting the behavior of a system as complex as our climate - is problematic. Previous predictions - were that temperatures would rise - and continue rising. https://www.clima...e-index/

Oh my Thorium - the models were correct. Now the behavior of details within that system - such as water levels in the great lakes - is obviously more complex - and predicting the behavior of that sub sub sub system - more problematic. https://theconver...s-118095

So maybe YOU don't value the predictions of science. But don't project your ignorance onto all of us Thorium.

Jul 16, 2019
Were you born stupid or did you have to practice?

Definitely Both... lol

Jul 16, 2019
Thorium
No one sane puts one cent of investment into the prognostications of environmentalists
Predicting the behavior of a system as complex as our climate - is problematic. Previous predictions - were that temperatures would rise - and continue rising. https://www.clima...e-index/

So maybe YOU don't value the predictions of science. But don't project your ignorance onto all of us Thorium.
.........when are you gonna actually apply some science & get those solar panels installed on your house that you've been here talking about doing for the past ten years? You plan to wait until the ocean levels are right at your doorstep before you do your part in fixing the problem?

"predictions of science" greeno? Since when is failed Climatology a science? But the light is getting brighter, right greeno.

Jul 16, 2019
Benni
You plan to wait until the ocean levels are right at your doorstep before you do your part in fixing the problem?
Hey Benni - why don't you live your life - and I will live mine. That is a very libertarian ideal - that stupid socialists like yourself would not understand. How about focusing on the science - and stop attacking people on a personal level. It makes you look like Trump.

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