Abstract:
A survey of biodiversity in the Central and Southern Transantarctic mountains including: Invertebrates (Collembola, Acari, Nematoda, Tardigrada, Rotifera); Lichens, Mosses, and Soil microbiology. Samples were also taken to enable cosmogenic dating techniques.
Quality
Quality indicators for MODIS snow data can be found in the following three places: * AutomaticQualityFlag and the ScienceQualityFlag metadata objects and their corresponding explanations: AutomaticQualityFlagExplanation and ScienceQualityFlagExplanation located in the ... CoreMetadata.0 global attributes * Custom local attributes associated with each SDS, for example, snow cover * Snow Spatial QA field. These quality indicators are generated during production or in post-production scientific and quality checks of the data product. For more information on local and global attributes, go to one of the following links: * MOD10A1 and MYD10A1 Local Snow Cover Attributes, Version 5 * MOD10A1 and MYD10A1 Global Snow Cover Attributes, Version 5
The AutomaticQualityFlag is automatically set according to conditions for meeting data criteria in the snow mapping algorithm. In most cases, the flag is set to either Passed or Suspect, and in rare instances, it may be set to Failed. Suspect means that a significant percentage of the data were anomalous and that further analysis should be done to determine the source of anomalies. The AutomaticQualityFlagExplanation contains a brief message explaining the reason for the setting of the AutomaticQualityFlag. The ScienceQualityFlag and the ScienceQualityFlagExplanation maybe updated after production, either after an automated QA program is run or after the data product is inspected by a qualified snow scientist. Content and explanation of this flag are dynamic so it should always be examined if present in the external metadata file. The algorithm tests for a variety of anomalous conditions and sets the pixel value accordingly if such conditions are detected. Summary statistics about missing data, the percent cloud cover, the percent of good or other quality data, and snow cover percent are calculated and placed in the metadata for each product. The Snow Spatial QA data field provides additional information on algorithm results for each pixel within a spatial context, and is used as a measure of usefulness for snow-cover data. The QA information tells if algorithm results were nominal, abnormal, or if other defined conditions were encountered for a pixel (Riggs, Hall, and Salomonson 2006). The NASA Goddard Space Flight Center: MODIS Land Quality Assessment Web site provides updated quality information for each product.
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City:
Boulder
Province or State:
CO
Postal Code:
80309-0449
Country:
USA
Publications/References
Diner, D. J., J. V. Martonchik, C. Borel, S. A. W. Gerstl, H. R. Gordon, Y. Knyazikhin, R. Myneni, B. Pinty, and M. M. Verstraete. 1999. MISR Level-2 Surface Retrieval Algorithm Theoretical Basis Document. Pasadena, CA: Jet Propulsion Laboratory.
Earth Science Data and Information System (ESDIS). 1996. EOS Ground System (EGS) Systems and Operations Concept. Greenbelt, MD: Goddard Space Flight ... Center.
Greuell, W. and J. Oerlemans. (2005). Validation of AVHRR- and MODIS-Derived Albedos of Snow and Ice Surfaces by Means of Helicopter Measurements. Journal of Glaciology, 51(172):37-48.
Hall, Dorothy K., George A. Riggs, and Vincent V. Salomonson. September 2001a. Algorithm Theoretical Basis Document (ATBD) for the MODIS Snow-, Lake Ice- and Sea Ice-Mapping Algorithms. Greenbelt, MD: Goddard Space Flight Center.
Hall, Dorothy K. and J. Martinec. 1985. Remote Sensing of Ice and Snow. London: Chapman and Hall.
Hall, Dorothy K., J. L. Foster, D. L. Verbyla, A. G. Klein, and C. S. Benson. 1998. Assessment of Snow Cover Mapping Accuracy in a Variety of Vegetation Cover Densities in Central Alaska. Remote Sensing of the Environment 66:129-137.
Hall, Dorothy K., J. L. Foster, Vincent V. Salomonson, A. G. Klein, and J. Y. L. Chien. 2001b. Development of a Technique to Assess Snow-Cover Mapping Accuracy from Space. IEEE Transactions on Geoscience and Remote Sensing 39(2):232-238.
Hall, Dorothy K. and George A. Riggs. 2006. Assessment of Errors in the MODIS Suite of Snow-Cover Products. Hydrological Processes.
Hapke, B. 1993. Theory of Reflectance and Emittance Spectroscopy. Cambridge: Cambridge University Press.
Justice, C. O. 2002. An Overview of MODIS Land Data Processing and Product Status. Remote Sensing of the Environment, 83(1):3-15. Klein, A. MODIS Snow Albedo Prototype. 2003.
Klein, A. G. and Julienne Stroeve. 2002. Development and Validation of a Snow Albedo Algorithm for the MODIS Instrument. Annals of Glaciology 34:45-52.
Klein, A. G., Dorothy K. Hall, and George A. Riggs. 1998. Improving Snow-Cover Mapping in Forests Through the use of a Canopy Reflectance Model. Hydrologic Processes 12(10-11):1723-1744.
Markham, B. L. and J. L. Barker. 1986. Landsat MSS and TM Post-Calibration Dynamic Ranges, Exoatmospheric Reflectances and At-Satellite Temperatures. EOSAT Technical Notes 1:3-8.
MODIS Characterization and Support Team (MCST). 2000. MODIS Level-1B Product User's Guide for Level-1B Version 2.3.x Release 2. MCST Document #MCM-PUG-01-U-DNCN.
Painter, Thomas H. and J. Dozier. 2004. Measurements of the Hemispherical Directional Reflectance of Snow at Fine Spectral and Angular Resolution. Journal of Geophysical Research-Atmospheres, 109(D18):D18115. doi:10.1029/2003JD004458.
Pearson II, F. 1990. Map Projections: Theory and Applications. Boca Raton, FL: CRC Press, Inc.
Riggs, George A., Dorothy K. Hall, and Vincent V. Salomonson. December 2006. MODIS Snow Products User Guide to Collection 5. PDF.
Stroeve, Julienne, Anne Nolin, and K. Steffen. 997. Comparison of AVHRR-Derived and In Situ Surface Albedo Over the Greenland Ice Sheet. Remote Sensing of the Environment, 62:262-276.
Stroeve, Julienne, J. E. Box, Terry Haran. 2006. Evaluation of the MODIS (MOD10A1) Daily Snow Albedo Product Over the Greenland Ice Sheet. Remote Sensing of the Environment, 105:155-171.
