NASA Study Details Rapid Melting of Arctic Sea Ice

NASA has released a study, conducted by a team of scientists at the Jet Propulsion Laboratory in Pasadena, Calif., which concludes that a dramatic shrinkage in the Arctic ice pack has occurred recently.

The data shows that “Arctic perennial sea ice, which normally survives the summer melt season and remains year-round, shrunk abruptly by 14 percent between 2004 and 2005,” said NASA’s bulletin. “According to researchers, the loss of perennial ice in the East Arctic Ocean was even higher, nearing 50 percent during that time as some of the ice moved from the East Arctic to the West.”

NASA pointed out that the decrease in perennial sea ice – 720,000 square kilometers (280,000 square miles) – equals an “area the size of Texas.” The perennial ice, which is frequently 3 or more meters (10 or more feet) thick, has been “replaced by new, seasonal ice only about 0.3 to 2 meters (one to seven feet) thick that is more vulnerable to summer melt.”

The study further concludes that the “decrease in the perennial ice raises the possibility that Arctic sea ice will retreat to another record low extent this year. This follows a series of very low ice-cover years observed over the past four summers from active and passive microwave satellite data.”

There are two conclusions to be drawn from this and similar studies that will affect the insurance industry: 1) An ice free Arctic opens the possibility of new maritime routes that would greatly shorten present day shipping times, but could pose greater risks to vessels. 2) As all that melted ice turns to water it will raise sea levels, putting low lying islands and coastal areas at greater risk of serious flood damage and rendering them more vulnerable to storms.

The JPL team, led by Son Nghiem, used NASA’s QuikScat satellite to measure the extent and distribution of perennial and seasonal sea ice in the Arctic. The survey found that, “while the total area of all the Arctic sea ice was stable in winter, the distribution of seasonal and perennial sea ice changed significantly.”

“Recent changes in Arctic sea ice are rapid and dramatic,” Nghiem asserted. “If the seasonal ice in the East Arctic Ocean were to be removed by summer melt, a vast ice-free area would open up. Such an ice-free area would have profound impacts on the environment, as well as on marine transportation and commerce.”

The researchers are examining what may have caused the rapid decrease in the perennial sea ice. So far they’ve indicated that “data from the National Centers for Environmental Prediction, Boulder, Colo., suggest that winds pushed perennial ice from the East to the West Arctic Ocean (primarily located above North America) and significantly moved ice out of the Fram Strait, an area located between Greenland and Spitsbergen, Norway. This movement of ice out of the Arctic is a different mechanism for ice shrinkage than the melting of Arctic sea ice, but it produces the same results – a reduction in the amount of perennial Arctic sea ice.”

They’ve also concluded that, “if the sea ice cover continues to decline, the surrounding ocean will get warmer, further accelerating summer ice melts and impeding fall freeze-ups. This longer melt season will, in turn, further diminish the Arctic ice cover.”

Nghiem cautioned that the recent Arctic changes are not well understood and many questions remain. “It’s vital that we continue to closely monitor this region, using both satellite and surface-based data,” he noted.

The above report is one of three sea ice study results being released by NASA. “These findings are the result of a new study by NASA; the U.S. Army Cold Region Research and Engineering Laboratory, Hanover, N.H.; and the National Ice Center, Washington, D.C.,” said the bulletin. “Study results are published in a recent issue of Geophysical Research Letters.

For more information about QuikScat, visit:
For more information about NASA and the agency’s programs, go to:

Ed. Note: Articles such as this one, which document findings about global warming/climate change, inevitably produce strong reactions from IJ readers. Many applaud such studies, while a similar number dismiss them as so much hype and simply a way for researchers to get government funds.

While the IJ welcomes comments from proponents of either view, consider this: The above study – one of many on the subject – was not conducted by an independent think tank, or even a reinsurance company, but by NASA, JPL and the U.S. Army. Their scientists get paid to do research, not to back some ideological agenda. Their findings should be taken seriously, and not simply derided as flawed because they happen to conclude that the world, especially in the Arctic regions, is warming.

Any comments citing contrary evidence, or the possibility that the warming trend could reverse itself, as it has done in the past, would therefore be of more use to the insurance industry, than simply stating “I don’t believe it,” or blaming the messengers by accusing them of having a biased agenda.