As of June 2023, this data set is retired and no longer available for download. We recommend using the Images of Antarctic Ice Shelves, Version 2 (https://nsidc.org/data/nsidc-0102/versions/2) data set, which was released on 5 May 2022 and also includes the Images of Antarctic Ice Shelves, Version 1 data. Changes in the extent and stability of ice shelves in the Antarctic Peninsula prompted NSIDC to begin a monitoring program using data from the AVHRR Polar 1 km Data Set. NSIDC regularly reviews images of those ice shelves considered susceptible to rapid change due to climatic warming, and of several other major shelves that occasionally calve major icebergs. The images in this site represent a selected subset of the available scenes, generally the clearest and most informative scenes available. The scenes are derived from either the AVHRR visible (vis) or the thermal (temp) channels, enhanced by combining two channels using principal components processing. In the thermal images, bright areas are colder areas. A few additional scenes from other sensors (MODIS, Landsat) are included to provide some supplemental information on ice shelf structure and events. The data from October 1992 to June 2009 are derived from past AVHRR and MODIS data; the data from 2001 to present are derived using MODIS Aqua and Terra Level 1B Calibrated Radiances. If you wish to save an image, you can do so through the 'Save image as' option of the browser's pop-up menu. For more information contact NSIDC User Services.