The scientists explained a sudden rise in temperature during the ice age. Then the North Pole of our planet drastically increased by 15%. And the reason for this is the change in the level of CO2 in the atmosphere and the restructuring of the currents in the Atlantic Ocean.
Researchers do not claim that history will repeat itself in the future due to an increase in the concentration of carbon dioxide in the atmosphere. But the results of scientific work show that very sharp climatic metamorphosis can occur under the influence of smooth changes.
The last time the ice age on Earth came about 2.6 million years ago – and it has not been completed yet. Its distinctive feature is the variability of the area of the ice cover and the temperature of the earth’s surface. Every 40 and 100 thousand years the glaciers advanced and receded, and the planet cooled and heated.
“Frosts” and “thaws” depend on the so-called cycles of Milankovic – the “rocking” of the earth’s orbit, which affect how strongly the sun warms the poles and temperate latitudes, according to a number of scientists. Other researchers associate climatic periods with changes in ocean currents or the growth / loss of CO2 in the atmosphere.
Gerrit Lohmann from the Alfred Wegener Institute in Bremerhaven (Germany) adheres to the second version. His computer model of the Earth during the glacial period showed that even a smooth growth or a fall in the level of CO2 in the atmosphere can lead to almost instant climatic upheavals.
A practical example – the CO2 content increased to 180 ppm (minimum for the glacial period) to 220 ppm (50% of the current level). The result was two very important events.
First, the weather phenomenon El Niño was formed, which transports warm water from the Pacific tropics to temperate latitudes. Secondly, the Gulf Stream and the associated Atlantic currents gained momentum. Because of this, the poles grew very hot, in some places – at 15 degrees Celsius. As a result, sea and surface ice rapidly disappeared.
When the proportion of CO2 in the atmosphere fell below the minimum, the climate quickly took its previous positions, the ice sheet grew again, and the Earth cooled.