MODIS/Aqua Sea Ice Extent 5-Min L2 Swath 1km, Version 4  View Catalog Page Entry ID
MYD29
Summary
MODIS/Aqua Sea Ice Extent 5-Min L2 Swath 1km (MYD29) contains the following fields: sea ice by reflectance, sea ice by reflectance pixel quality assurance (QA), ice surface temperature (IST), IST pixel QA, sea ice by IST, combined sea ice, latitudes, and longitudes in HDF-EOS format along with corresponding metadata. Latitude and longitude geolocation fields are at 5 km resolution while all other fields are at 1 km resolution. Version 4 (V004) MYD29 data, the most current version available, uses Aqua/MODIS band seven instead of band six. The sea ice algorithm uses a Normalized Difference Snow Index (NDSI) modified for sea ice to distinguish sea ice from open ocean based on reflective and thermal characteristics. The only data available for Version 4 (V004) is the Golden Month, which is a sample of V004 data covering the time period 29 August 2002 (day of year 241) through 7 October 2002 (day of year 280). The Golden Month is only available by special request by contacting NSIDC User Services.
Please note that NSIDC now has a complete series of Version 5 data, which is the highest version number now available and represents the best quality of data.
Multimedia Sample
View full image
Caption: MYD29 Version 4 data, 05 February 2004
|
Geographic Coverage
Spatial Coordinates:
N: 90°
S: -90°
E: 180°
W: -180°
|
Data Set Citation
Dataset Creator: D. Hall, V. Salomonson
Dataset Title: MODIS/Aqua Sea Ice Extent 5-Min L2 Swath 1km, Version 4
Dataset Release Date: 2000-09-01
Dataset Release Place: Boulder, CO
Dataset Publisher: National Snow and Ice Data Center (NSIDC)
Version: 4
Online Resource: http://nsidc.org/data/myd29.html
Temporal Coverage
Start Date: 2002-07-04
Stop Date: 2006-12-31
Data Resolution
Temporal Resolution: 5-min
Location Keywords
- Geographic Region Global Ocean
Science Keywords
- Cryosphere Sea Ice Ice Extent
- Cryosphere Sea Ice Ice Temperature
- Oceans Sea Ice Ice Extent
- Oceans Sea Ice Ice Temperature
Ancillary Keywords
- Antarctic
- Arctic
- Climatology
- DAAC
- EASE-Grid
- ECS
- EOSDIS
- Global Change
- Gridded
- Ice Surface Temperature
- IST
- NASA
- NSIDC
- Polar
- Remote Sensing
- Sea Ice
- Swath
- Climatology/Meteorology/Atmosphere
Platform
- AQUA Earth Observing System, AQUA
Instrument
- MODIS Moderate-Resolution Imaging Spectroradiometer
- SPECTRORADIOMETERS
Project
- EOSDIS Earth Observing System Data Information System
- ESIP Earth Science Information Partners Program
Quality
In MYD29 Version 4 (V004) data, the sea ice algorithm uses Aqua/MODIS band 7. Good quality has been observed in the sea ice maps; however, investigation of effects of the switch to band 7 is continuing. The cloud mask product, MYD35_L2, used as input to the MYD29 algorithm also changed to use of band 7. The effect of that change relative to sea ice/cloud discrimination is being investigated. The IST was not affected by the switch to band 7 except, possibly indirectly by the cloud mask switch to band 7. Validation status is set at provisional until further validation work specific to Aqua IST maps can be completed.
Provisional means that the products are partially validated; incremental improvements are still occurring. These are early science validated products and are useful for exploratory and process scientific studies. Quality may not be optimal since validation and quality assurance are ongoing. Users are urged to review product quality summaries before publication of results.
Analysis of the quality of the sea ice data products is an ongoing activity. Specific information on the science quality of the sea ice data products is reported in the ScienceQualityFlagExplanation object in the CoreMetadata.0 global attribute. The URL for the quality assessment site is given in the product metadata and is linked to from the EOS Data Gateway (EDG) when ordering data. The ScienceQualityFlagExplanation is changed in response to analysis and should be checked for updated information. In the MOD29 and MOD29P1D data products there are two instances of the ScienceQualityFlagExplanation, one for sea ice determined by reflectance data and one for IST written in the metadata. Information on both is posted at that URL.
The Ice Surface Temperature PixelQA and the Sea Ice by Reflectance PixelQA data fields provide additional information on algorithm results for each pixel within a spatial context, and are used as a measure of usefulness for sea ice data. QA data are stored as bit flags. QA information is extracted by reading the bits within a byte (See MODIS Sea Ice Quality Assurance Fields). The QA information tells if algorithm results were nominal, abnormal, or if other defined conditions were encountered for a pixel (Riggs, Hall, and Salomonson 2003).
See MODIS Land Quality Assessment for further details.
Data Set Progress
COMPLETE
Data Center
National Snow and Ice Data Center
Data Center URL: http://nsidc.org
Data Set ID: MYD293, MYD294
Data Center Personnel
Name: NSIDC User Services
Phone: +1 (303) 492-6199
Fax: +1 (303) 492-2468
Email: nsidc@nsidc.org
Contact Address:
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
NSIDC Distributed Active Archive Center
Data Center URL: http://nsidc.org/daac/index.html
Data Set ID: MYD293, MYD294
Data Center Personnel
Name: NSIDC DAAC User Services
Phone: +1 (303) 492-6199
Fax: +1 (303) 492-2468
Email: nsidc@nsidc.org
Contact Address:
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
Distribution
Distribution Media: upon request
Distribution Size: 0.5-6.0
Distribution Format: HDF-EOS
Personnel
George A. Riggs
Role: INVESTIGATOR
Contact Address:
NASA Goddard Space Flight Center (GSFC)
Science Systems and Applications, Inc.
Mail stop 614.1
City: Greenbelt
Province or State: MD
Postal Code: 20771
Dorothy K. Hall
Role: INVESTIGATOR
Contact Address:
National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC)
Mail stop 614.1
City: Greenbelt
Province or State: MD
Postal Code: 20771
Vince V. Salomonson
Role: INVESTIGATOR
Contact Address:
Room 809 WBB
Department of Meteorology
University of Utah
City: Salt Lake City
Province or State: UT
Postal Code: 84112
Country: US
NSIDC USER SERVICES
Role: TECHNICAL CONTACT
Phone: +1 (303) 492-6199
Fax: +1 (303) 492-2468
Email: nsidc@nsidc.org
Contact Address:
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
Related URL
VIEW PROJECT HOME PAGE
MODIS DAAC Web page at NSIDC
VIEW PROJECT HOME PAGE
MODIS Data at NSIDC Home Web page
Reference
Earth Science Data and Information System (ESDIS). 1996. EOS ground system (EGS) systems and operations concept. Greenbelt, MD: Goddard Space Flight Center. Hall, D. K., A. B. Tait, G. A. Riggs, and V. V. Salomonson. 1998. Algorithm Theoretical Basis Document (ATBD) for the MODIS Snow-, Lake Ice- and Sea Ice-Mapping Algorithms (Version 4.0). Electronic version is available online at http://snowmelt.gsfc.nasa.gov/MODIS_Snow/atbd.html.
Hall, D. K. and J. Martinec. 1985. Remote sensing of ice and snow. London: Chapman and Hall.
Key, J. R., J. B. Collins, C. Fowler, and R. S. Stone. 1997. High latitude surface temperature estimates From thermal satellite data. Remote Sensing of the Environment 61:302-309.
Key, J. R., J. A. Maslanik, T. Papakyriakou, M. C. Serreze, and A. J. Schweiger. 1994. On the validation of satellite-derived sea ice surface temperature. Arctic 47:280-287.
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. MODIS Web. MODIS Science and Instrument Team. 2001. http://modis.gsfc.nasa.gov/.
Pearson II, F. 1990. Map projections: theory and applications. Boca Raton, FL: CRC Press, Inc.
Riggs, G., D. Hall, and V. Salomonson. 2001. MODIS sea ice products user's guide. Electronic version is available online at http://modis-snow-ice.gsfc.nasa.gov/siugkc.html.
Riggs, G. A., D. K. Hall, and S. A. Ackerman. 1999. Sea ice extent and classification mapping with the Moderate Resolution Imaging Spectroradiometer Airborne Simulator. Remote Sensing of the Environment 68:152-163.
Wiscombe, W. J. and S. G. Warren. 1980. A model for the spectral albedo of snow I: pure snow. Journal of the Atmospheric Sciences 37:2712-2733.
Metadata Name and Version
Metadata Name: CEOS IDN DIF
Metadata Version: 9.7
Creation and Review Dates
DIF Creation Date: 2003-05-23
Last DIF Revision Date: 2008-03-26
| 
