Abstract
The natural climate of Earth has always been and continues to be in constant evolution. Several thousands of years ago, and before the current climate became warm, the whole Earth was much colder when a huge mass of ice covered the major part of Europe, Russia and North America. It was the last ice age. The reheating of several world areas, during these last years, owed either to air pollution by man, or to natural changes that can be the result of a global planet reheating. These variations can change the climate over much longer periods that we are incapable to note. Climate change and Earth reheating are a major risk for ecological balance and human activities. They are, at the same moment, a political and economic stake for all planet countries. We discuss the various aspects of climate change and the differences it creates on our planet.
