The Extreme Ice Survey was the first to document the retreat of the massive Columbia Glacier, Alaska, above.
Photograph by Chris Johns, National Geographic
On June 22, 2006, Extreme Ice Survey (EIS) photos were taken of the Columbia Glacier, Alaska, the first in a series documenting changes in the extent of glacial ice, year after year. The EIS is a large-scale study of glaciers using real-time photography. EIS uses time-lapse photography to show seasonal and multi-year changes in glacial ice in Greenland, Iceland, Alaska, and the Rocky Mountains.
The time-lapse photography shows the natural process of glacial accumulation and ablation. Accumulation is when a glacier grows—usually in the winter, when snowfall and other precipitation build up (accumulate). Ablation is when a glacier retreats or shrinks—usually in the summer, due to icemelt. Long-term trends, including those documented by EIS, show that Earth’s glaciers are retreating more than they are growing.
removal of material from the surface of an object, including melting, evaporation, or erosion.
a buildup of something.
mass of ice that moves slowly over land.
all forms in which water falls to Earth from the atmosphere.
photographing of a slow and continuous process at regular intervals, for projection at a higher speed.