NIMA declassifies images for climate study

The National Imagery and Mapping Agency this week declassified 59 satellite images of the Arctic Ocean that will be used by scientists interested in understanding connections between polar ice caps and global warming.

The release of the high-resolution images came at the request of the National Science Foundation, a primary sponsor for an international expedition to the Arctic that has documented changes in the ice pack.

The expedition, called the Surface Heat Budget of the Arctic Ocean project, also is sponsored by Canada and Japan. The project involved deliberately trapping a Canadian icebreaker in Arctic ice for a year between 1997 and 1998. More than 100 scientists took measurements of the atmosphere, ocean and ice with the help of the trapped ship.

Preliminary findings from the project reveal that the Arctic ice sheet is about 5 percent smaller and one meter (about 39.5 inches) thinner than in the 1970s. Some scientists argue that a smaller ice pack will translate into more rapid global warming because ice reflects more solar radiation into the atmosphere than water.

The just-released images track the interred ship during the course of several months as it drifted with the ice. Over the course of the year the ship was stuck in ice, the ship and the surrounding ice traveled about 1,500 miles.

Several of the newly declassified images can be viewed at www-nsidc.colorado.edu/TEST/NTM/.

The catalog of images could be available as soon as fall through the ARCSS Data Coordination Center at the National Snow and Ice Data Center.