Summer appeared on Earth 13 thousand years ago – the specialists

2017-09-22 09:03

Summer appeared on Earth 13 thousand years ago – the specialists
During this “era of instability” explicit summer was not.

Austrian scientists venovali that summer as a relatively clearly separated time of the year, appeared on Earth no earlier than 13 thousand years ago.

The content of the work briefly recounts the Xinhua News Agency,reports Rus.Media

The authors of the new study studied these deposits in the Austrian lake Lange, samples of which were raised with depths from 3.4 to 4.4 meters. Accordingly, the sediments ranged from 19 thousand to 13 thousand years. Scientists analyzed the composition of plants, in particular algae, the remains of which are preserved in the lake. The nature of the vegetation, the researchers can reconstruct the past climate. So, shrubs, herbs and many algae are able to withstand the cold climate and harsh temperature extremes, and the trees need a more stable and warm weather.

According to the results of their work, the authors made a conclusion that after the end of the last ice age about 20 thousand years ago, the Earth gradually began to warm up. About 17 thousand years ago the average temperature dropped sharply, and this local minimum lasted for about 2.5 thousand years. About 14.5 thousand years ago, the climate again became warmer.

During this “era of instability” explicit summer was not. The water temperature in the lake during the cold period did not rise above 10 degrees Celsius, while the warm rose only to 18 degrees. Scientists suggest that atmospheric temperature was also unstable.

The climate of ancient Earth still remains a subject of disputes of scientists. On the temperature regime of the planet in the past, the researchers can judge only by indirect signs, so the interpretations of different groups you can often run into contradictions. However, almost all scientists agree that in the past the planet has experienced several periods of global warming and global cooling.