What Are the Factors Responsible for Ice Ages?
Ice Age is a time when much of the Earth is very cold, and sheets of ice cover large parts of the land. During the last Ice Age, ice covered much of Europe and North America. It disappeared about 10,000 years ago. The last Ice Age might not have truly finished, however. Many scientists believe we may be living through a warm spell in the Ice Age and Earth should be gearing up to go through another ice age soon.
Ice Ages have changed the shape of the land, because moving ice, known as a glacier, cuts through and erodes rocks. If the earth moves away from the sun it becomes colder. Dust from volcanoes can cover the earth, blocking out some of the sun’s heat. These and other factors may have caused the Ice Ages.
There have been at least five major ice ages on Earth throughout its history, with the last one ending roughly 12,800 years ago. These ice ages lasted for hundreds of thousands of years and saw temperatures drop sharply across the globe – cold enough to stop snow from melting and causing glaciers to form.
Changes in Earth’s radiation balance were the principal driver of past climate changes, but the causes of such changes are varied. For each case – be it the Ice Ages, the warmth at the time of the dinosaurs or the fluctuations of the past millennium – the specific causes must be established individually. In many cases, this can now be done with good confidence, and many past climate changes can be reproduced with quantitative models.
Due to human activity and the pumping of greenhouse gasses into the atmosphere, the next ice age has been seriously delayed. Carbon dioxide traps heat within the atmosphere, which is preventing the planet from going into another cooling cycle. This is yet further evidence that human activity is destroying the fragile ecosystem of the planet.