110 likes | 324 Views
The Melting Of The Polar Ice Caps. The current status of the ice caps.
E N D
The current status of the ice caps • The National Snow and Ice Data Center, in Boulder, Colorado, announced that the Arctic sea ice had reached a new low. The sea ice shrinks in the summer and grows again during winter’s long polar night. It usually reaches its minimum extent in mid-September. On September 16, 2012, the N.S.I.D.C. reported, the sea ice covered 1.3 million square miles. This was just half of its average extent during the nineteen-eighties and nineties, and nearly twenty per cent less than its extent in 2007, the previous record-low year.
It would be difficult to overstate the significance of this development. We are now seeing changes occur in a matter of years that, in the normal geological scheme of things, should take thousands, even millions of times longer than that. On the basis of the 2012 melt season, one of the world’s leading experts on the Arctic ice cap, Peter Wadhams, of Cambridge University, has predicted that the Arctic Ocean will be entirely ice-free in summer by 2016. Since open water absorbs sunlight, while ice tends to reflect it, this will accelerate global warming. Meanwhile, recent research suggests that the melting of the Arctic ice cap will have, and indeed is probably already having, a profound effect on the U.S. and Europe, making extreme weather events much more likely.
What is causing the polar ice caps to melt? • The basic factor that is attributed to the melting of the polar ice caps is global warming. • Scientists have spent decades figuring out what is causing global warming. They've looked at the natural cycles and events that are known to influence climate. But the amount and pattern of warming that's been measured can't be explained by these factors alone. The only way to explain the pattern is to include the effect of greenhouse gases (GHGs) emitted by humans.
Green House Gasses One of the first things scientists learned is that there are several greenhouse gases responsible for warming, and humans emit them in a variety of ways. Most come from the combustion of fossil fuels in cars, factories and electricity production. The gas responsible for the most warming is carbon dioxide, also called CO2. Other contributors include methane released from landfills and agriculture (especially from the digestive systems of grazing animals), nitrous oxide from fertilizers, gases used for refrigeration and industrial processes, and the loss of forests that would otherwise store CO2. Different greenhouse gases have very different heat-trapping abilities. Some of them can even trap more heat than CO2. A molecule of methane produces more than 20 times the warming of a molecule of CO2. Nitrous oxide is 300 times more powerful than CO2. Other gases, such as chlorofluorocarbons (which have been banned in much of the world because they also degrade the ozone layer), have heat-trapping potential thousands of times greater than CO2. But because their concentrations are much lower than CO2, none of these gases adds as much warmth to the atmosphere as CO2 does.
Effects On The Planet • A research team led by scientists from the University of Arizona have used the National Elevation Dataset produced by the U.S. Geological Survey to predict how sea level rises could affect coastal cities by 2100. This is the first such study to include every coastal city with a population above 50,000.Based on projections that sea levels will rise about 1 metre by the end of the century, the analysis suggests the southern Atlantic and Gulf coasts could be particularly hard hit • Miami, New Orleans, Tampa, Fla., and Virginia Beach, Va. could lose more than 10 percent of their land area by 2100. • The press release goes on to say predicted levels global warming could lock us into further sea level rises due to melting Greenland and Antarctic ice sheets • By 6 meters (about 20 feet), about one-third of the land area in U.S. coastal cities could be affected.
The Importance Of The Ice Caps • Recent studies since the year 2004 on polar bears and global warming have shown an alarming increase of polar bear drowning. Since polar bears are basically good swimmers, researchers were puzzled how and why they drowned. Investigations soon showed that the combination of fewer and smaller ice floes and erratic climate changes have contributed to this situation. • http://www.youtube.com/watch?feature=player_embedded&v=E1cyUmx5htA • The result of melting ice caps means that polar bears and global warming is a fatal combination – because many bears are now drowning due to lack of ice floes to hunt and den on. • The main importance of the ice caps is keep the climate in check, and serve as a habitat for hundreds of species. As the ice caps begin to disappear these species are rapidly headed towards extinction.
How Can We Slow The Melting Of The Ice Caps? • Alternative fuel research is continuing everyday, from hydrogen powered, electric, and hybrid vehicles. • Ethanol is also a much greener alternative to burning fossil fuels that caused this whole mess in the first place. • Wind, Solar, and Hydro electricity are also a much greener approach at producing clean renewable energy.