Why does the earth go through ice ages repeatedly?

The earth will experience this kind of glacial period again and again, in fact, it is very normal, the glacial period is due to the change of the earth's crust on the surface of the earth, then the formation of glaciers, only by repeatedly experiencing such a phenomenon, the earth can be particularly cold, and human beings can survive.

This is determined by a variety of factors, as weather and climate are inherently a cyclical thing.

Because the Earth's glacial periods are influenced by sunspot activity, which is periodic, the Earth goes through glacial periods repeatedly.

The Earth has experienced four glacial ages, the most recent of which was 2.5 million years ago.

The Earth has experienced a total of four ice ages before. In the Precambrian period, hundreds of millions to hundreds of millions of years ago, the earth experienced the First glacial period, and in the billions to billions of years ago, the earth encountered the Second glacial period. The Tertiary glacial period experienced by the Earth was between 100 million and 100 million years ago, and the glacier coverage expanded to the entire southern hemisphere; The famous Quaternary glacial period began 2.5 million years ago and continues to this day.

The Earth has gone through a total of four ice ages. And each glacial period lasted for a long time. Therefore, we must take care of the ecological environment.

The Earth has gone through 4 glacial periods.

1. In the Precambrian period, hundreds of millions to hundreds of millions of years ago, our earth experienced the First Ice Age. The glacier covered Australia, Europe, the Americas and parts of Asia on a large scale;

2. Between 100 million and 100 million years ago, the earth encountered the Second Ice Age. The glacier covers Africa, South America, Europe, and northern North America.

3. The Tertiary glacial period experienced by the earth was between 100 million and 100 million years ago, and the glacier coverage area expanded to the entire southern hemisphere;

4. The famous Quaternary glacial period began 2.5 million years ago and has continued to this day, and we are now living in the Quaternary glacial period. At the beginning of the Quaternary glacial period, glaciers covered the entire Northern Hemisphere.

The advent of the Quaternary glacial period led to the extinction of a large number of biological species, because there was a relatively long interglacial period before the Quaternary glacial period, when the climate was warm and the environment was suitable for the survival of organisms, which can be said to be a very comfortable "peaceful world". As the saying goes, "Born in sorrow, die in peace", the adaptability of organisms to live in such an environment gradually deteriorates, and even degrades, as a result, when large-scale glaciers come, many species go extinct. For example, the mammoths we see in fossils today lived in large numbers during the interglacial period before the arrival of the Quaternary glacial period.

At the same time, during the ice age, some species became extinct, and new species were born, such as the highest living beings on the earth, humans, who were born and evolved during the Quaternary Ice Age.