Isotopes in Stalactites May Link Intensifying Thunderstorms to Global Climate Variability (sciencealert.com) 22
Long-time Slashdot reader schwit1 shares an interesting report from Science Alert:
Thunderstorms that roil across the Southern Great Plains of the US are amongst the strongest of such storms on Earth... Their intensity and frequency have been increasing, yet our best climate models still struggle to predict just how and when they'll arise.
To help refine climate models for the Southern Great Plains, paleoclimatologist Christopher Maupin from Texas A&M University and colleagues used oxygen and hydrogen isotopes to track the ferocity of past storms. Water molecules based on elements wielding an additional neutron or two tend to require a little more energy to vaporize, and release more energy as they condense. This leaves a clear signature in the ratios of isotopes separated by rainfall under various conditions. By comparing the results of analyses taken today with historic ratios of hydrogen and oxygen isotopes found trapped by stalactites in Texan caves, the researchers developed an accurate picture of weather events in the past...
Using another set of isotopes, this time measuring those of uranium and thorium, the team dated the stalactites and stalagmites to around the last Ice Age, 30-50 thousand years ago. Measuring the shifts in oxygen and hydrogen isotopes down their lengths allowed the researchers to see the storms cycled from weakly to strongly organized, roughly every thousand years. The more strongly organized the complex of storms becomes, the more intense and damaging they are. They discovered these changes in thunderstorm intensities coincided with well-known, abrupt shifts in global climate, known as Dansgaard-Oeschger events.
The researchers also found these intensity increases coincide with a reduction in rain in southwestern US and greater atmospheric upwelling in the Santa Barbara Basin area. They believe the observed pattern suggests an increased frequency or intensity of the giant global atmospheric waves that drive the weather, called Rossby waves, may be providing the extra lift needed to fuel these greater storms. "Modern anthropogenic climate forcing has increasingly favored an amplification of these synoptic factors," the team wrote in their paper.
"This work will help predict trends of storms in the future," explained geoscientist Courtney Schumacher.
To help refine climate models for the Southern Great Plains, paleoclimatologist Christopher Maupin from Texas A&M University and colleagues used oxygen and hydrogen isotopes to track the ferocity of past storms. Water molecules based on elements wielding an additional neutron or two tend to require a little more energy to vaporize, and release more energy as they condense. This leaves a clear signature in the ratios of isotopes separated by rainfall under various conditions. By comparing the results of analyses taken today with historic ratios of hydrogen and oxygen isotopes found trapped by stalactites in Texan caves, the researchers developed an accurate picture of weather events in the past...
Using another set of isotopes, this time measuring those of uranium and thorium, the team dated the stalactites and stalagmites to around the last Ice Age, 30-50 thousand years ago. Measuring the shifts in oxygen and hydrogen isotopes down their lengths allowed the researchers to see the storms cycled from weakly to strongly organized, roughly every thousand years. The more strongly organized the complex of storms becomes, the more intense and damaging they are. They discovered these changes in thunderstorm intensities coincided with well-known, abrupt shifts in global climate, known as Dansgaard-Oeschger events.
The researchers also found these intensity increases coincide with a reduction in rain in southwestern US and greater atmospheric upwelling in the Santa Barbara Basin area. They believe the observed pattern suggests an increased frequency or intensity of the giant global atmospheric waves that drive the weather, called Rossby waves, may be providing the extra lift needed to fuel these greater storms. "Modern anthropogenic climate forcing has increasingly favored an amplification of these synoptic factors," the team wrote in their paper.
"This work will help predict trends of storms in the future," explained geoscientist Courtney Schumacher.
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We still have time to correct things, thus the urgency of this sort of news.
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Even more important: Do stalagmites predict the opposite?
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They mite.
*Yawn* (Score:2)
I'm going to let you guess who is funding their research. It rhymes with Koch Industries.
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It's a really interesting dating technique. If you turn off your ad hominem brain, I think you'll find the results unobjectionable.
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I do not doubt their research is thought provoking, it's correctness, or even the intentions of the scientists who worked on it. What I do doubt is that this got funded for reasons unrelated to casting doubt on climate change.
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What I do doubt is that this got funded for reasons unrelated to casting doubt on climate change.
IF that was their intention, they did a really bad job of it.
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Climate change denial isn't about coming up with a good theory, it's about coming up with something to muddy the waters. It doesn't matter if it's accurate or scientifically sound, just something that will provide cover to do nothing just a little longer. Several million dollars is nothing compared to what Koch Industries makes in a day, so if it only buys a day without additional regulation then it's paid for itself.
But... (Score:2)
Are they also compensating for the huge amount of these elements blasted in to the environment by cold war era ground level nuclear test explosions?
Dare we mention they're cyclical and common? (Score:1)
...or are we just going to blame anthropogenic sources this time again?
Hint:
"Dansgaardâ"Oeschger events take the form of rapid warming episodes, typically in a matter of decades, each followed by gradual cooling over a longer period. For example, about 11,500 years ago, averaged annual temperatures on the Greenland ice sheet increased by around 8 ÂC over 40 years, in three steps of five years (see,[3] Stewart, chapter 13), where a 5 ÂC change over 30â"40 years is more common."
Sound fami
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I do enjoy how any comment - no matter how factual, no matter how sourced - that casts the SLIGHTEST shadow on the dogma of global warming is immediately downmodded.
It's one of the characteristics of science as opposed to, say, a religion. Science is robust enough to withstand questions. In fact, that's how science advances - being tested.
Some Context (Score:2)
I suspect this is the mystery they are trying to solve.