A new study based on an analysis of climatic data conducted by researchers at the Hebrew University of Jerusalem and Columbia University in the USA: "Global warming is expected to cause even more widespread mega-droughts and fires across America, already in the near future"

In the last month we were exposed to the terrible results of drought, a heat wave and strong winds that caused many fires throughout the country and the world. The scientists of the Intergovernmental Panel on Climate Change (IPCC), including Prof. Daniel Rosenfeld from the Institute of Earth Sciences, are already warning that droughts and extreme heat waves will cause great suffering for millions of people in the coming decades and will lead to even more widespread fires than those we have seen in the Jerusalem mountains or overseas , in the USA (California) and Europe (Greece). Similarly, severe forms have occurred in the last decade in central Chile and the American Southwest the north and lead to extensive agricultural losses.
A new study led by Dr. Nathan Staiger from the Institute of Earth Sciences at the Hebrew University, Reveals future risks to major agricultural regions in North and South America. The study, published a few days ago in the international journal Nature Geoscience from Nature, Traces the temperature changes following the "La Niña" phenomenon, whose climate pattern over the past thousand years has repeatedly led to prolonged mega-droughts in North and South America at the same time. The findings reveal that climate change in these regions, which include the California region in the US and central regions in Chile and Argentina, have devastating ecological, agricultural and social consequences.
Dr. Steiger and his colleagues from Columbia University in the USA based themselves on the analysis of extensive data bases from archives, which record rainfall and temperatures in the past that showed that prolonged forms occurred regularly in the Americas. "We combined geological records and computer simulations of the global climate in order to locate the patterns of occurrence of droughts in North and South America throughout history. We discovered that the most severe types of droughts, known in the dialect as "mega-droughts", occurred repeatedly in the southwestern regions of North and South America at the same time. The findings Ours show that in such consecutive forms they are more than mere coincidence", explains Dr. Staiger.
12 mega forms in a thousand years
"We found that during the last millennium, about 12 extreme mega-droughts occurred both in the southwest of North America and in the southwest of South America. These are very extreme droughts that on average lasted about three decades in North America and about two decades in South America continuously", the researchers add. In this context, it is important to note that 7 of these events occurred simultaneously in both regions as a result of the abnormally cold temperatures in the central Pacific Ocean caused by the "La Nina" phenomenon. "'La Nina' conditions create huge atmospheric waves that push storms further poleward, moving them away from places like central Chile and southwestern North America", Dr. Steiger specifies.
The results indicate that in the future extreme drought that will last for decades may affect all the western regions of America. Under global warming, the western regions of North and South America are expected to become even drier. According to the researchers, this will lead to even more severe and extreme droughts in these regions, which we now know can be synchronized by temperature changes in the tropical Pacific Ocean.
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