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Energy Business Review
The move marks a step ahead for returning nuclear power to the country following the Fukushima disaster of 2011, which led to the shutdown of all nuclear facilities. The safety report has been approved by NRA as the idled reactors comply with the new and …
Global warming will bring the “unprecedented” risk of a decades-long mega-drought in the American Southwest and Great Plains during the second half of the century, researchers claim.
The forecast, which was published online Thursday in the new journal Science Advances, contrasts sharply with other recent assessments that report greater uncertainty about future droughts, according to study authors.
Mega-drought in our future?
Scientists say the American Southwest could be in for a mega-drought by the end of the century.
The researchers used historic tree ring data and three drought measures to conclude that there was at least an 80% chance of a 35-year-long drought occurring by the end of this century.
“Imagine a naturally occurring drought, such as the one occurring in California … imagine that going on for decades … that’s kind of a mega-drought,” said lead study author Benjamin Cook, a climatologist at NASA Goddard Institute for Space Studies.
Cook and his coauthors — Toby Ault, a geoscientist at Cornell University, and Jason Smerdon, a climate scientist at Lamont-Doherty Earth Observatory of Columbia University — discussed their research at a San Jose teleconference Thursday.
Although many scientists agree that California’s current drought is the result of natural climate variability, and not the result of global warming, Cook and his colleagues said human-produced greenhouse gasses were increasing the likelihood of future droughts.
Higher temperatures, low precipitation and increased rates of evaporation would result in drier soils, they said.
The researchers said their model was based on predicted emissions, and that reductions in those emissions could mitigate future drying.
‘Hi, do you have water?’ In a Central Calif. town, answer is often no.
‘Hi, do you have water?’ In a Central Calif. town, answer is often no.
“We’re not necessarily locked into these levels of mega-drought risk if we slow the effects of rising greenhouse gas on global temperatures,” Ault said.
Very lengthy and extreme periods of drought have affected Southern California and much of the Western United States in the past, although long before the founding of the nation.
According to scientists, paleoclimatic evidence suggests that intense periods of dryness occurred in this region from the 9th to the 14th centuries, a period now called the Medieval Climate Anomaly.
Cook and his colleagues said future drought risk probably will exceed that of the Medieval Anomaly.
“Our results point to a remarkably drier future that falls far outside the contemporary experience of natural and human systems in Western North America, conditions that may present a substantial challenge to adaptation,” the authors wrote.
“Human populations in this region, and their associated water resource demands, have been increasing rapidly in recent decades, and these trends are expected to continue for years to come.”
Back in November, the island nation of Madagascar confirmed 119 cases of plague, including 40 deaths. But the bad news recently took a disturbing turn: “The fleas that transmit this ancient disease from rats to humans have developed resistance to the first-line insecticide,” Margaret Chan, director-general of the World Health Organization, said in a new report.
You probably recognize the infectious disease as the one known as the “Black Death,” which during the 14th century became a devastating epidemic that claimed an estimated 50 million lives throughout Europe, Asia, and Africa. Caused by the bacteria Yersinia pestis, the disease spreads from rodents to humans via infected fleas. Those infected generally develop bubonic plague—exhibiting swollen lymph nodes and flu-like symptoms—or, if it spreads to the lungs, the deadlier advanced form, pneumonic plague. Caught early, antibiotics can effectively treat the disease; left untreated, however, plague kills 30 to 60 percent of those infected.
Steamboats from India carried plague to Madagascar in 1898. What makes the recent outbreak there particularly troubling is that scientists have been warning about insecticide resistance in fleas for years. Plague surveillance in Madagascar was discontinued in 2006 due to a lack of funding, but almost 17 years ago—and just six years after the first-line insecticide was initially used in Madagascar—an article published in the Journal for Emerging Infectious Diseases closed with the admonition, “the increasing resistance of fleas to insecticides have caused much concern.”
A November 2014 study conducted by the health research center Institut Pasteur in Madagascar found conclusive evidence that more than 80 percent of the fleas tested were resistant to Deltamethrin, the insecticide referenced in the WHO report. Out of the 32 flea populations examined, only two demonstrated susceptibility to the insecticide. The report’s authors conclude, “In the…re-emergence of plague…in Madagascar, Deltamethrin is ineffective against fleas. Its use in Madagascar should be stopped and the control program for plague diseases needs to change to another insecticide.”
While the study explains that many factors could contribute to the fleas’ increased resistance to insecticides—including environment, climate, geography, urbanization, and human social and cultural behaviors—the core mechanism at work is natural selection. Each time a population of fleas is treated with insecticide, fleas that by some quirk have a built-in resistance survive and breed to create the next generation of fleas, born genetically resistant to the insecticide that wiped out their parents’ peers. Over time, the insecticide becomes less effective as the flea populations are increasingly comprised of only those with the quirk of DNA that protects against it. To compensate for its lowered levels of efficacy, a higher concentration of the insecticide is often used—which breeds a generation of fleas even more resistant than the last.
For the people of Madagascar, Deltamethrin restistance is a case of déjà vu all over again. Use of the insecticide, a man-made version of a natural insecticide that chrysanthemum flowers produce, began in the 1990s after insects developed resistance to the flea-control chemical being used at the time. Some scientists have hypothesized that fleas’ resistance to Deltamethrin may be a result of the species’ exposure to the old insecticide.
What can be done? For now, Institut Pasteur researchers are testing 12 insecticides to see which will be most effective at controlling flea populations. Without plague surveillance, however, there is no way to tell how long it will take for the fleas to build resistance to the next line of insecticides. Funding shortfalls also continue to stand in the way of those trying to track and control plague in Madagascar—not to mention the growing number of other health concerns the institute must deal with: When Sébastien Boyer, head of the medical entomology unit at the institute, was contacted for comment on the status of the insecticides currently being tested, he responded by e-mail, “No time…we are currently in malaria outbreak in Farafangana…sorry.”
Long-lasting mega-droughts could occur with increasing frequency in the western United States later this century if no action is taken to rein in climate change by curbing fossil fuel use, researchers said.
Mega-drought is defined as any drought as bad as the worst already seen in the 20th century, but lasting much longer, for 35 years or more.
The study is the first to predict that the coming intense dry spells could exceed the decades-long mega-droughts that occurred centuries ago and are blamed for the demise of certain civilizations in the late 13th century.
“I was honestly surprised at just how dry the future is likely to be,” said co-author Toby Ault, an assistant professor in the Department of Earth and Atmospheric Sciences at Cornell University.
“I look at these future mega-droughts like a slow moving natural disaster. We have to put mega-droughts into the same category as other natural disasters that can be dealt with through risk management.”
The risks and dangers are worse today because of the larger population and greater dependence on water resources, scientists warned.
“We are the first to do this kind of quantitative comparison between the projections and the distant past, and the story is a bit bleak,” said Jason Smerdon, a co-author and climate scientist at the Lamont-Doherty Earth Observatory, part of the Earth Institute at Columbia University.
“Even when selecting for the worst mega-drought-dominated period, the 21st century projections make the mega-droughts seem like quaint walks through the Garden of Eden.”
– ‘Unfavorable’ forecast –
Researchers applied 17 different climate models to analyze the future impact of rising temperatures on regions from Mexico to the United States and Canada.
They also projected a continued rise in emissions of the greenhouse gases that contribute to global warming, and looked at a scenario in which actions were taken to cut back on greenhouse gases resulting in lower emissions. Both approaches raised concern for the future.
“The results… are extremely unfavorable for the continuation of agricultural and water resource management as they are currently practiced in the Great Plains and southwestern United States,” said David Stahle, professor in the Department of Geosciences at the University of Arkansas who was not involved in the study.
Currently the western United States has been experiencing a drought for about 11 of the past 14 years.
The dry area spans California, Nevada, New Mexico, Arizona, Texas and Oklahoma and other parts of the region, directly affects more than 64 million people.
“Natural droughts like the 1930s Dust Bowl and the current drought in the Southwest have historically lasted maybe a decade or a little less,” said Benjamin Cook of the NASA Goddard Institute for Space Studies and the Lamont-Doherty Earth Observatory.
“What these results are saying is we’re going to get a drought similar to those events, but it is probably going to last at least 30 to 35 years.”
The research was presented at the American Association for the Advancement of Science annual meeting, and published in a new AAAS online journal called Science Advances
PORTLAND, Ore. (Reuters) – Scientists from two U.S. Pacific Northwest laboratories plan to conduct tests of unusual precipitation that fell across the region over the weekend in hopes of pinpointing the origins of so-called “milky rain” that has mystified residents, officials said on Wednesday.
Officials at both the Pacific Northwest National Laboratory and the Benton Clean Air Agency, both in Washington state, said they had collected samples of the rain, which left a powdery residue on cars across a wide swath of the two states.
Scientists at the Richland lab said they believe the rain may have carried volcanic ash from an erupting volcano in Japan, while the clean air agency said its staffers believe dust from central Oregon was the culprit.
The National Weather Service has said it believes the powdery rain was most likely a byproduct of dust storms hundreds of miles away in Nevada, although it could not rule out volcanic ash from Japan as a possible culprit.
But the National Weather Service has also said it was not equipped to perform a chemical analysis of the rain that would be required to pinpoint its origins.
Wherever the milky precipitation came from, officials say they do not believe it poses any health risk. Air monitoring stations did not detect anything unusual while the rain was falling, said Robin Bresley Priddy, executive director of Benton Clean Air.
“We don’t have any reason to think there’s anything wrong, but there’s no reason not to be cautious if you’re concerned,” she added. “You may want to wash it off your car with water, rather than with your hands, and avoid touching it and breathing it in.”
|Santa Fe New Mexican.com
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