When scientists talk about the cryosphere, they mean the places on Earth where water is in its solid form, frozen into ice or snow. Read more ...
On Friday, 06 February 2015 from 8:00 a.m. to 5:00 p.m. (USA Mountain Time), we will be performing scheduled maintenance, which may cause temporary disruptions to our Web site, applications, and FTP. We apologize for any inconvenience this may cause you.
layer of soil or rock, at some depth beneath the surface, in which the temperature has been continuously below 0°C for at least several years; it exists where summer heating fails to reach the base of the layer of frozen ground.