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.
the line of latitude 66° 34′ S (often taken as 66.5° S); along this line the sun does not set on the day of the summer solstice, and does not rise on the day of the winter solstice.