Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Sperry Glacier area change, 1950 - 2014. Sperry Glacier occupies a broad, shallow cirque situated just beneath and west of the Continental Divide in the Lewis Mountain Range of Glacier National Park, Montana.
Public Domain.
