About 90 million years our planet was quite different. In the so-called Cretaceous period, which will be discussed in this article, on the surface of the earth were a huge dinosaurs and volcanoes erupted more often and stronger than it is now. Since the eruptions in the atmosphere of our planet got a lot of water vapor and carbon dioxide on Earth there was a strong greenhouse effect. Water vapor and carbon dioxide covered planet like a plastic bag and did not give the incident sunlight reflected back toward space. As a result, the planet almost always be warm and even now in the cold Antarctica, the average temperature was about 13 degrees Celsius. This means that it was not so much snow and ice as it is now. Maybe, there is generally grown in tropical forests?
The land in the time of dinosaurs
Scientists already have good reasons to assume that in the time of dinosaurs in Antarctica was flowing relatively warm river and grew tall trees. In 2017, the crew of the German research vessel “of Polarstern” decided to go to the ice-covered sea Amundsen and drill it on the bottom of a deep hole. Thus, they wanted to find soil samples of the times of the Cretaceous period, so studying their composition they could find the remains of ancient plants. When they reached the place, they drilled at the bottom of the sea hole with a depth of 30.7 meters. He had extracted the core, which amounted to about 88 million years. This is the time of the Cretaceous period, which was of interest to researchers.
The core is a rock sample which was mined from deep hole on the surface of the Earth. By studying the extracted materials, scientists can determine the climate that reigned in ancient times, as well as to recognize the types of ancient plants.
Ancient plants in Antarctica
Studying ancient soil scientists headed by Professor Johann Clayson (Johann P. Klages) actually found the fossilized remains of plant roots, and pollen. Comparing these remains with the roots and pollen of modern plants, they could find that on the territory of ancient Antarctica was growing conifers, ferns and plants with flowers. At the moment we can confidently say that 90 million years ago Antarctica was growing up:
- Conifers of the family Podocarpaceae, which are now found in South America and Africa;
- Conifers of the family Araucariaceae, which can be found in Australia and Islands of New Guinea;
- A huge number of fernin the family Cyatheaceae, which today comprises 514 species;
- Flowering plants of the genus Beauprea, the closest relatives of which are African Proteas.
It turns out that millions of years ago, the now cold Antarctica was an area covered with lush, green vegetation. Scientists also believe that between the forest flowed the river with fresh water — the trees have something to eat? The words and images of artists of ancient Antarctica appears as a hot, tropical place. But in fact the climate by today’s standards was not so comfortable because the average temperature clearly did not exceed 13 degrees Celsius. It was only a little nicer in the summer when the air was heated up to 18.5 degrees. It is also known that in ancient Antarctica pretty frequent rains — the mean annual rainfall was 1120 mm, while in modern Moscow every year falls approximately 707 mm.
In addition to formed under the influence of volcanoes thrown up the greenhouse effect, the increase in air temperature promoted and growing in Antarctica trees. The fact that the dense vegetation did not give the sunlight reflected from the Earth’s surface and the forest area of Antarctica as if attracted heat. The ability of forests, water, sand, snow and other surfaces of our planet to reflect sunlight is called albedo of the earth’s surface. Plant forests have a low albedo, so in their places of accumulation of relatively warm climate. And snow and ice albedo is high, so that modern Antarctica reflects much of the sunlight does not retain the warmth and is a pretty cool place.
The forest existed in Antarctica tens of millions of years and is likely to have disappeared 70 million years ago. Then the location of the continents on our planet started to change, which undoubtedly affected the activity of volcanoes. As a result of changes in volcanic activity, sea levels, and many other innovations, the temperature on our planet began to fall and in places reached -45 degrees Celsius.