The existence of ice sheets, which appeared and disappeared in a short period of time, at a time when the temperature was between 6 and 12 degrees Celsius higher than now, contradicts the general assumption that the poles did not have ice at the time of extreme heat, which is suspected it would happen again in the future if left unchecked, the current global warming. In fact, according to research published in ‘Science’, an estimated 200,000 years ago there were glaciers around 60% of the size of the current Antarctic ice sheet. In reaching this conclusion, an international team of scientists has obtained data from sediments deposited in the equatorial Atlantic Ocean. The sea of Suriname is where you have found fossils of tiny sea creatures, foraminifera, that lived in the Turonian period, as it is called the Cretaceous period. Thanks to the analysis of chemical composition, scientists at the Scripps Institution of Oceanography United States have been able to reconstruct the temperature in the Turonian was on the surface and the deep sea. Similarly, British, German and Netherlands have studied the molecular composition of these sediments, which also gives clues to the marine environment in that distant prehistory. With both combined data and knowing that chemical changes are constant in the ocean when there is ice, “has been confirmed that there were large chunks of ice for short periods of the Cretaceous, in which the world was much warmer than it is today , or will in the near future, something that would not have evidence yet, “said the Briton Thomas Gagner, one of the authors of this paper. S. Japps Damste, one of his colleagues, remember that these results are in line with other research conducted in Russia and the United States, according to which the water level dropped by then 25 to 40 meters, which occurs when the ice appears. In fact, today the Antarctic ice is estimated to contain enough water to raise sea level about 60 meters if completely thawed. “The study shows that even at very warm Cretaceous could not prevent the increase of ice, though obviously there were fewer numbers than in other periods of glaciation, and that would have made it possible for tropical plants and even crocodiles in the Arctic,” he adds Andre Bornmann, team has carried out the work.
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