(ORDO NEWS) — At least, this is what the authors of a curious study claim, which established the exact date of the beginning of the Late Dryassic cooling.
The Younger Dryas, which began about 12,900 years ago and lasted about 1,200 years, was a period of extreme climatic conditions. A sharp cooling then occurred almost within a few years and interrupted the Allerd warming, when a climate close to today was established on Earth.
Since the last ice age that resulted from this cooling is separated from us by a relatively short period of time, scientists can study it with a fairly high degree of accuracy.
They were able to establish the moment of a sharp climate change with an approximate error of a hundred years, but, as Professor Christoph Shpetl from the University of Innsbruck says, even such accuracy is insufficient – many events and processes could occur in a hundred years.
Therefore, the research group, one of the leaders of which was Professor Shpetl, tried to clarify the date of the onset of the ice age, using previously obtained ice samples and samples of sinter deposits collected by them in the caves of China, India, Uzbekistan, Brazil and Spain.
As a result, it turned out that the cooling began in the North Atlantic 12,870 years ago, and from there the movement of atmospheric and oceanic masses spread it to the south. According to Shpetl, such assumptions have already been made by scientists, but have not yet been confidently proven.
At the end of the ice age, however, the process was reversed – warming began in the Southern Hemisphere and / or in the tropical regions of the Pacific Ocean, then moving north.
At the same time, the authors of the study refuted one of the hypotheses about the causes of the onset of the ice age. In 2012, American scientists discovered sediments at the bottom of Lake Cuitzeo in Mexico, proving that a meteorite fell to Earth at the beginning of the Younger Dryas, which could affect climate change.
This theory was later confirmed by other findings. However, it is considered. that the fall of the meteorite occurred 12820 years ago, that is, 50 years later than the established exact date of the beginning of the cooling. And besides, as the Austrian professor notes, at the time of the alleged collision in Greenland, no significant changes in climate were detected.
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