Melting Artic Sea Ice

This scary story comes courtesy of ABC News:

An area of Arctic sea ice the size of Florida has melted away in just the last six days as melting at the top of the planet continues at a record rate.

2007 has already broken the record for the lowest amount of sea ice ever recorded, say scientists, smashing the old record set in 2005.

Currently, there are about 1.63 million square miles of Arctic ice, according to the National Snow and Ice Data Center in Boulder, Colo. That is well below the record of 2.05 million square miles set two summers ago and could drop even lower before the final numbers are in. ...

Scientists say the rate of melting in 2007 has been unprecedented, and veteran ice researchers worry the Arctic is on track to be completely ice-free much earlier than previous research and climate models have suggested.

Since it is already in the ocean, sea ice does not raise ocean levels when it melts. However, the melting exposes greater areas of dark ocean water to sunlight. Instead of reflecting sunlight, like ice, the ocean absorbs the energy and warms more quickly. The loss of sea ice is a matter of concern for conservation of polar bears and other arctic creatures. It also increases worries about the possibility of reaching a tipping point when warming will accelerate.