Glaciers & Icepack

Changes in the extent of permanent and seasonal ice can serve as important indicators of short-term and long-term climate change. The volume of ice in the world’s mountain glaciers is declining (see Earth Observatory feature on Glaciers).

While the relationship of glacier dynamics to regional climate is not well defined, scientists cite the worldwide recession of mountain glaciers during the last century as evidence for global warming. Mountain glaciers and small ice fields reflect changes in regional climate more quickly because their small size makes them sensitive to deviations from normal weather patterns. From the International Space Station, seasonal images of glaciers will provide valuable detailed information about the extent of glacial ice and surface snows (or equilibrium line) on the glaciers. Beyond the issues of global warming and rising sea levels, the retreat of glaciers and ice fields also has implications for current and future regional water resources. Astronauts are focusing on large ice and glacier fields in the Canadian Rockies, small glaciers atop high peaks in the equatorial regions (for example, Papua New Guinea and Mt. Kilimanjaro in Tanzania), and snowfields in the Andes, from Bolivia and Peru to Patagonia. The first photographs of glaciers have already been downlinked by Station crewmembers.

Sea ice can also serve as an important indicator of global climate change. Winter ice accumulation in the Gulf of St. Lawrence varies dramatically during El Niño events (Evans et al. 2000). Crewmembers will photograph limits of South Sandwich Islands pack ice as well.
 

 Tectonic Processes and Craters
 El Niño cycles