  According to scientists from Nasa and the National Snow and
Ice Data Center in Boulder, Colorado, the ice cover is the
smallest in the three decades since the polar cap has been
monitored by satellite.  The ice is measured by a Special Sensor
Microwave Imager, on a US spacecraft. The ice is currently 1.58
million square miles.  nasa ice  Sunset in the Arctic: Each
year, the ice cap melts throughout the summer months before
expanding through winter  Today's ice is 27,000 square miles
smaller than 2007, when 1.61 million square miles of ice were
measured.  And the 2012 "melt season" could still continue for
several weeks, resulting in an even larger loss of ice.   But
over the last three decades, satellites have observed a 13%
decline per decade in the sea ice, which is measured when it is
at its smallest, and the ice is steadily getting thinner.  ice
caps   Joey Comiso, senior research scientist at Nasa, said the
results were particularly unusual, because temperatures had not
been exceptionally warm.  He sai