New Zealand contains over 3,000 glaciers, most of which are in the Southern Alps on the South Island. Since 1890, the glaciers have been retreating, with short periods of small advances. The differences between 1990 (Landsat image from January 12) and 2017 (ASTER image from January 29) can be seen in the pair of images, that include the Mueller, Hooker and Tasman Glaciers. Notice the larger terminal lakes, the retreat of the ice free of moraine cover, and the higher moraine walls due to ice thinning. The images cover an area of 39 by 46 km, and are located at 43.7 degrees south, 170 degrees east.
With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan’s Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products.
The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.
The U.S. science team is located at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA’s Science Mission Directorate, Washington, D.C.
More information about ASTER is available at http://asterweb.jpl.nasa.gov/.
Image credit: NASA/METI/AIST/Japan Space Systems, and U.S./Japan ASTER Science Team