RAMP AMM-1 SAR Image Mosaic of Antarctica, Version 2
In 1997, the Canadian RADARSAT-1 satellite was rotated in orbit so that its Synthetic Aperture Radar (SAR) antenna looked south towards Antarctica. This permitted the first high-resolution mapping of the entire continent of Antarctica. In 18 days, the satellite acquired a complete coverage of radar image swaths as part of the first Antarctic Mapping Mission (AMM-1). Swath images were assembled into an image mosaic depicting the entire continent at 25 m resolution. The mosaic provides a detailed look at ice sheet morphology, rock outcrops, research infrastructure, the coastline, and other features of Antarctica, as well as representing calibrated radar backscatter data, which may provide insight into climate processes affecting the upper few meters of snow cover.
Data are available via FTP, and are offered in a variety of formats. A series of approximately 90 image tiles covers the entire continent at 25 m resolution, and single mosaic images derived from these tiles cover the continent at resolutions ranging from 125 m to 1 km. The single images provide good detail in convenient image formats. The tile products preserve the highest resolution of spatial detail, and retain the quantitative measure of backscatter intensity, but are necessarily large files that require assembly by the user.
Version 2 Summary
Removed Version 1 data because of a number of image processing problems that were fixed in Version 2 data. Version 2 data benefits from the following error corrections and other updates:
The effects of Automatic Gain Control (AGC) used in initial data gathering by the satellite remain in the Version 2 images. In collecting the data, a region of each swath is sampled for intensity so that the gain of the processed data may be set optimally for increased contrast over the surface to be imaged. Within swaths that include abrupt changes in surface type, for example, near the coast or near rock outcrops, this initial sample may include only water or rock outcrop, and thus the gain is set for these surfaces rather than for ice. The section of the swath is processed with gains that are not optimal for the ice sheet mosaic. The affected regions of the ice sheet show up as slightly darker blocks or corners within the mosaic.
The following example shows how to cite the use of this data set in a publication. For more information, see our Use and Copyright Web page.
Jezek, K. C., J. C. Curlander, F. Carsey, C. Wales, and R. G. Barry. 2013. RAMP AMM-1 SAR Image Mosaic of Antarctica. Version 2. [indicate subset used]. Boulder, Colorado USA: National Snow and Ice Data Center.