Why is the polar ice cap melting and what are the repercussions?
Many scientists believe that global warming is melting Arctic ice so rapidly that the region is beginning to absorb more heat from the sun, causing the ice to melt still further and so reinforcing a vicious cycle of melting and heating. The vast expanse of permanent ice that has characterized the Arctic Ocean for millennia is fated to disappear far faster than anyone imagined, and will certainly be gone before the century is out, says a NASA satellite study. The NASA survey shows that an area of ancient ice roughly as large as Alberta is vanishing every decade as the climate warms. Over the course of this NASA survey, which ran from from 1978 to 2000, about 1.2 million square kilometers of supposedly permanent ice melted away — more than the total area of Ontario. And the rate of the melt — roughly 9 per cent a decade — is speeding up, said physicist Josefino Comiso, senior scientist at NASA’s Goddard Space Flight Center in Maryland and author of the study. A good and brief intervie
The polar ice cap is melting because average global temperatures have increased by about 0.2 degrees Celsius in 20 years. That average global temperatures have increased is proven by empirical data. Obviously, ice melts when temperatures increase. The debate is around WHY average global temperatures have increased (global warming). Scientific consensus is that greenhouse gases have caused global warming. Evidence also strongly suggests that the sun is burning hotter in the past 100 years than it has at any time during the previous 1,000 years. http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2004/07/18/wsun18.xml&sSheet=/news/2004/07/18/ixnewstop.html Scientists have taken core samples of artic ice and confirmed that the levels of carbon dioxide and other greenhouse gases are at their highest levels in the last 800,000 years or so. This highly suggests that the increase in these gases is not due to cyclical planetary climate changes, but due to human activity. http://news.bbc.co.uk
