Climate scientists: in the United States at any time can be the most powerful drought

© AP Photo / Manish SwarupМужчина on the dam dried Manjara Dam in India. 2016Climate scientists: in the United States at any time can be the most powerful drought© AP Photo / Manish Swarup

. American scientists analyzed the history of droughts over the last two thousand years and came to the conclusion that in the West and southwest of the United States may at any time be «mahasiswa» that will last at least 30 years, according to a paper published in the Journal of Climate.

«Using our model, we were able to better understand the role played by «magazasi» in the normal fluctuations of the Earth’s climate and what drives the likelihood of their occurrence. It is surprising that even these simple calculations show that such disasters can easily occur in the coming years, and that their power will not concede to the great droughts of the past that occurred in Western North America in the last 1,200 years,» said Toby Ault (Ault Toby) from Cornell University in Ithaca (USA).

Starting in 2011, in the southern regions of the United States raging drought that affected 98 percent of California residents and nearly all its forests, many of which are almost completely dried up during this time. To combat it, California authorities took a very severe restrictive measures, which are comparable to the draconian restrictions on water consumption during a drought in the 1970-ies, which were articulated but not applied in practice.

Scientists estimate that only in the last five years, California has lost about 67 cubic kilometers of water, and before the onset of «hurricane» at the end of December last year, the situation was fast approaching critical. After a series of powerful rain in January, the state government announced the completion of the drought, but climate scientists fear that the situation may change again

Ault and his colleagues sought to determine how frequently such events might occur in the past and find a way to predict a similar drought in the future, studying data collected by paleoclimatology in the study of the history of the reservoirs existing on the territory of West and South-West USA in the last two thousand years.

The authors were interested in one simple question, was there a long drought themselves, as a result of «natural» climate fluctuations, or arise only for some external reasons. In their role there may be a sharp change in the nature of the movements of ocean currents, dimming or increasing the brightness of the Sun, geological disasters and other factors.

To answer it, scientists have created a set of climate models, in which the birth of droughts drove or disasters, or climatic fluctuations, and have compared the results of calculations that showed paleoclimatic data. Climatologists, as Walt explains, was not interested in the time and place of the occurrence of a specific drought, and their frequency, timing, and the number of small and big events of this kind.

As shown by these calculations, major droughts do occur primarily because of random fluctuations in the Earth’s climate, but some of their properties depend on external events, for example, the probability that several major droughts will start almost at the same time and reinforce each other’s action.

All of this suggests that a powerful drought, ongoing for 30 years, can occur in the Western United States, even if the planet’s climate will not change in the future. Such disasters, as they note, affect the territory of many States and their authorities should be prepared that such problems can occur in any of the following summer or winter season.

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