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The National Snow and Ice Data Center (NSIDC) and the University of New Hampshire assembled two digital image maps and two snow-grain-size images of the Antarctic continent and surrounding islands that provide a nearly-perfect cloud-free view of the ice sheet, ice shelves, and land surfaces using two different sets of data:
The MOA2004 Image Map consists of two cloud-free digital image maps that show mean surface morphology and a quantitative measure of optical snow grain size on the Antarctic continent and surrounding islands using 260 orbit swaths from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on board the NASA EOS Aqua and Terra satellites. The 260 orbit swaths used to create the 2003-2004 MOA Surface Morphology Image Map and the 2003-2004 MOA Grain Size Image Map were acquired 20 November 2003 through 29 February 2004 for the full spring-summer season. The 122 orbit swaths used to create the 2003 MOA Grain Size Image Map were acquired 1 November 2003 through 17 December 2003 for the shortened spring-only season. Vector data sets with the corresponding coastlines, ice sheet grounding lines, and islands are also provided.
The MOA2009 Image Map consists of two cloud-free digital image maps that show mean surface morphology and a quantitative measure of optical snow grain size on the Antarctic continent and surrounding islands using 259 orbit swaths from the MODIS instruments on board the NASA EOS Aqua and Terra satellites. The 259 orbit swaths used to create the 2008-2009 MOA Surface Morphology Image Map and the 2008-2009 MOA Grain Size Image Map were acquired 1 November 2008 through 28 February 2009 for the full spring-summer season. The 142 orbit swaths used to create the 2008 MOA Grain Size Image Map were acquired 1 November 2008 through 16 December 2008 for the shortened spring-only season. Vector data sets with the corresponding coastlines, ice sheet grounding lines, and islands are also provided.
MOA2004 and MOA2009 provide a cloud-free view of the ice sheet, ice shelves, and land surfaces at a grid scale of 750 m and 125 m and an estimated resolution of 150 m to 200 m. The mosaic includes all land areas and islands south of 60° S that are larger than a few hundred meters. Land areas north of 60° S and areas of ocean more than a few tens of kilometers from coastlines are masked with zero-fill. Also included are several persistent fast ice areas and grounded icebergs.
The 125 m grid images have spatial coverage identical to the Radarsat Antarctic Mapping Project Antarctic Mapping Mission 1 (RAMP AMM-1) 125 m mosaic. The MOA image maps are complimentary to the radar-image-based RAMP mosaic, highlighting true surface morphology without a subsurface volume backscattering component. This results in a better discrimination between accumulation- and crevasse-related subsurface changes and surface features.
Image data for MOA2004 are available via FTP or through the MOA Image Map Server that can create manually-selected JPEG images, and permits on-the-fly zoom, a series of contrast stretches, and geolocated image delivery. However, image data for MOA2009 are only available via FTP. Image data on the FTP site are provided as 16-bit images to preserve the radiometric content of the scenes; for the JPEG images, a variety of pre-processed contrast stretches are available.
Citing These Data
As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.
Haran, T., J. Bohlander, T. Scambos, T. Painter, and M. Fahnestock 2005, updated 2013. MODIS Mosaic of Antarctica 2003-2004 (MOA2004) Image Map. [indicate subset used].Boulder, Colorado USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5ZK5DM5.
Haran, T., J. Bohlander, T. Scambos, T. Painter, and M. Fahnestock. 2014. MODIS Mosaic of Antarctica 2008-2009 (MOA2009) Image Map. [indicate subset used]. Boulder, Colorado USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5KP8037.
We kindly request that you acknowledge the use of this data set by referencing the following peer-reviewed publication:
Scambos, T., T. Haran, M. Fahnestock, T. Painter, and J. Bohlander. 2007. MODIS-based Mosaic of Antarctica (MOA) Data Sets: Continent-wide Surface Morphology and Snow Grain Size. Remote Sensing of Environment 111(2): 242-257. http://dx.doi.org/10.1016/j.rse.2006.12.020..
For more information on this data set, contact User Services at NSIDC.
| This is an example of a mosaic image at low resolution with an inset of the Steershead Ice Rise, showcasing the detail available through MOA.
This image, generated by combining the snow-grain-size image and the high-pass filtered Band 1 image in a Hue-Lightness-Saturation (HLS) transformation, shows a region of blue ice and coarse snow. The region contains the Queen Fabiola Mountains in East Antarctica. This was the site of a very large accumulation of meteorites deposited by ice flow and ablation on the blue ice surface.