Drop in Carbon Dioxide Levels Led to Polar Ice Sheet, Study Finds

Scientist at Yale and Purdue, state that a climate change can be caused by the change in carbon dioxide. For example, the drop in carbon dioxide made an ice sheet form over the Antarctic. Before the ice sheet can melt the greenhouse gases have to increase, how much is still unknown. Due to the ice sheet and change in climate many species became extinct over about 100,000 years. Before the drop in carbon dioxide all kinds of species inhabited the North and South Poles and Earth has subtropical climates and it was warm and wet. Since the ice sheet formed over the Antarctic the sea levels fell. Carbon dioxide had an importance from the past to the present. They do not know what caused the rise and fall in the carbon dioxide level, but they study ancient algae in the deep ocean sediments and crust.

Drop in Carbon Dioxide Levels Led to Polar Ice Sheet

According to a recent study by scientists at Yale and Purdue, a drop in carbon dioxide appears to be the reason why an ice sheet is forming in the Antarctic. The role of the greenhouse gas supports carbon dioxide's importance in past, present, and future climate change. Researchers have found a threshold for low level of carbon dioxide below which an ice sheet forms in the South Pole. However, it remains a mystery of how much the greenhouse gas has to increase to melt the ice sheet. A professor at Purdue said there was about a 40 percent decrease in carbon dioxide before and during the formation of a thick ice sheet over the Antarctic about 34 million years ago. The evidence shows that carbon dioxide controls global climate. If the amount of carbon dioxide is increased or decreased, there could be dramatic changes. Another professor from Yale says that polar ice sheets and sea ice control a large amount of modern climate. It influences the global circulation of air masses, patterns of precipitation, and wind strengths. The recognition of the important role of carbon dixide change is an important finding.

http://www.sciencedaily.com/releases/2011/12/111201174225.htm