Climatologists announced the beginning of the era of «great floods» in the Amazon

© AP Photo / Marcio Jose SanchezДевочка in a boat on the Amazon river, near Manaus, BrazilClimatologists announced the beginning of the era of «great floods» in the Amazon© AP Photo / Marcio Jose SanchezПодпишись to daily updates RIA Science

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. The frequency of floods in the Amazon basin and their strength has increased about five times in recent years due to global warming and shifts in the pattern of currents and winds in the Atlantic, say scientists in an article published in the journal Science Advances.

«In the past, we were drawn to the history associated with the onset of severe droughts in the region. Now we have found evidence that the most powerful frequency of floods has increased dramatically. In fact, we can say that extreme floods occurred in the Amazon every summer beginning in 2009 and ending in 2015,» said Jonathan Baricevic (Jonathan Barichivich) from the University of Leeds (UK).

Two years ago Russia, USA, England and several other countries struck a number of extremely powerful weather events such as powerful rains and extreme heat in summer in Russia and in South Asia, floods during autumn and winter in England and the United States.

The frequency of different floods, periods of extreme heat and other unusual weather events in recent years, forcing many scientists to wonder whether they are related to climate change, and those changes in sea currents, movement of winds in the air and streams of water on the ground, which resulted in the increase in average temperatures.

Today scientists attribute many of these phenomena with changes in the nature of the work of the climatic phenomenon El niño, the motion of the waters of the North Atlantic current, and many other important «conductors» of weather and climate on Earth.

Baricevic and his colleagues discovered another example of the impact of global warming on the frequency of various disasters, analyzing the statistics on the water level in the river Rio Negro, one of the largest tributaries of the Amazon, which were collected by port authorities in the Brazilian city of Manaus since 1903.

This town, as researchers note, is near the point of confluence of Rio Negro in the Amazon, allowing you to use data on the level of water in the surrounding area for observing the status of the two largest rivers of Central South America.

Combining Chronicles of Manaus with satellite imagery and similar measurements at the narrowest part of the headwaters of the Amazon, scientists were able to reconstruct how often the floods on the territory of its basin in the last hundred years.

These observations revealed a disturbing trend – the incidence of floods as the most powerful and long-lasting and very severe droughts has increased markedly in the last 50 years, since 1970. In total, the incidence of the most severe flooding has increased about five times, and they began to occur in the lower reaches and in the headwaters of the Amazon.

The reason for the onset of the «age of floods», as the researchers note, was that global warming has accelerated and reinforced the so-called «Walker cell» systems of winds, linking the cold waters of the Pacific ocean and the warm waters of the Atlantic. Their acceleration, in turn, was associated with the warming of the Atlantic ocean, intensification of El niño and changes in the nature of the movement of the winds in the southern hemisphere.

Scientists assume that in the future the number of floods will grow even more as the water temperature in the Atlantic will continue to grow. On the other hand, if the Pacific ocean will become warmer, but the El niño will change its «sign», then the frequency of floods will decrease, but still remain very high, conclude Baricevic and his colleagues.

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