World of Change: Columbia Glacier its nose had retreated 12 miles north Columbia Glacier NASA Earth Observatory - Columbia Glacier, AK documented Columbia Glacier, Alaska Columbia Glacier, Alaska earthobservatory.nasa.gov NASA’s Earth Observatory Nézd meg a Columbia-gleccser olvadását Earth Observatory NASA, Jesse Allen, Robert Simmon recession NASA view slideshow Columbia Glacier World of Change: Columbia Glacier, Alaska The glacier Learn More About This Image retreat of the Mendenhall Glacier in Alaska