Today it seems to be a topic that is talked about almost every day, global warming. Opinions differ a lot about the cause of this event and whether it is not just a hoax. What we know for sure is that global warming has major consequences for humanity and nature. However, it is not the first time the earth has been warming up …
The last time the earth warmed up was around 4.6 billion years ago. It all happened in a span of 200,000 years, which is relatively small time for such a huge change. The earth was only just recovering from the extermination of the dinosaurs. Compared to the current time, it was already a lot warmer. For example, there were no ice caps on the poles.
However, in less than 20,000 years the temperature became even higher. It grew on average by 5 to 8 degrees Celsius. And the North and South Pole reached temperatures of 23 degrees Celsius. This had an enormous effect on the earth and all life on the earth. First of all, the rainforests expanded much further than they ever did. Even in Scandinavia, fossils are found that belong to the jungles that are only found in Brazil or Africa today.
Just like today, there is a lot of evidence that global warming was caused by a sharp rise in the number of greenhouse gases that were released into the air. It is thought that the cause of this was a huge and sudden increase in forest fires. It is also possible that huge volcanoes have erupted or that the gasses that were trapped in the ice caps have been released during the melting of the polar caps.
Unfortunately, a comparison has to be made here with today’s greenhouse gas emissions. According to recent studies, 1.4 billion cubic meters of gas was released into the atmosphere during the previous global warming. At the moment we are emitting 9.8 billion cubic meters of greenhouse gases, and this was only in the year 2014.
The consequences of the huge rise are, as mentioned earlier, a huge increase in forests and rainforests. This increase gave animals such as reptiles the chance to grow in populations and many mammals also evolved for the first time during this period. However, the ocean became so hot that life was no longer possible in many places. The ocean around the equator warmed up to 36 degrees Celsius. The oceans also became more acidic, which meant that many shellfish could no longer use their protection. As a result, an estimated 50 to 60% of all life in the ocean died out.
This warm period therefore had two sides. It gave life to many species of animals such as mammals, of which we are part of, but also made life impossible for much of life on earth that could not adapt soon enough. The period finally came to an end, after which the earth began to look like the one we know today. We just don’t know why the temperature dropped again.