The Carbon dioxide is the main reason for the end of the last ice age. This deprives the main argument of skeptics who do not believe that CO2 emissions are the cause of contemporary global warming.
About 10-20 thousand years ago, Earth began to emerge from the “freezing”, which lasted a quarter of a million years. Ice cover of the planet began to melt and global temperatures rise, which helped to spread humanity and conquer the planet. The reason for the end of the Ice Age has long been a subject of scientific debate. Finally, Harvard researchers were able to answer this question.
The main evidence of ancient climate change are air bubbles frozen in Antarctic ice. This kind of “time capsule”, which allows us to study the composition of the ancient atmosphere. Previous studies have shown that the concentration of the main greenhouse gas, CO2, and began to grow after the temperature has begun to recover, but not before. This gave the skeptics an opportunity to say that carbon dioxide emissions are not the main cause of global warming. Instead, the main reason they consider the natural changes in Earth’s orbit, ie when the planet approaches the Sun, comes yet another warming.
But a new study shows that the change of the orbit just “pulls the trigger,” but the real responsibility for global warming lies with the CO2. On the basis of the study 80 samples of ice and sediment collected in Greenland, the bottom of lakes and seas, scientists have concluded that CO2 emissions are actually preceded by global warming, but the whole process bigger than previously thought.
Changing the Earth’s orbit causes the heating and melting of sea ice, which throws into the North Atlantic gigatons of cold fresh water. This thread has a depressing effect on the “conveyor belt” of Atlantic currents, which in turn leads to heating of the Antarctic and Southern Ocean. As a result, the heated water is released into the atmosphere vast reserves of carbon dioxide, which create the greenhouse effect and dramatically heated the Earth.
This usually occurs during the oscillation of the orbit of the Earth and is very rare. So, the last time the rise in global temperature by 5 degrees C was observed 30 million years ago. At the same time CO2 pulling” the world of the Ice Age more than 10 thousand years, humanity has made a similar “success” for only 200 years old. While it is difficult to say what will happen to the Earth’s climate over the next hundred years, but the planet is beginning to respond to human activity.