The Sediment Analysis Network for Decision Support (SANDS) project, funded by NASA, focused on enhancing suspended sediment in satellite imagery related to tropical cyclones in the Gulf of Mexico. Since the year 2000, Eastern Louisiana, coastal Mississippi, Alabama, and the western Florida panhandle have been affected by 28 tropical storms, seven of which were hurricanes. These tropical cyclones have significantly altered normal coastal processes and characteristics in the Gulf region through sediment disturbance. Sediment deposits are changed in very short periods of time by these tropical storms. SANDS has generated decision support products that address the impacts of tropical storms and hurricanes on sediment disturbance, suspension, transport, and deposition in the north central Gulf of Mexico. NASA satellite observations from MODIS, Landsat, and SeaWiFS instruments, using color and infrared reflected bands, were used to produce these decision support products. Analyzed data from these instruments were enhanced to show suspended sediment carried out much farther into the Gulf than can be seen in normal true-color images. Increased area of sediment plumes from pre- to post- storm data can be visualized in the enhanced imagery and helps with comparison of pre- and post-storm runoff, sediment suspension, and transport patterns.
The MODIS data obtained for SANDS is a combination of MODIS Aqua and MODIS Terra data. These datasets are subsets of the raw data from the downloaded MODIS satellite product. The subsetted coordinates are 31- 27N latitude and 90 -84.25 W longitude (Gulf of Mexico coastline in Alabama and part of Florida). GeoTIFF images were created from this more defined area of subsetted data. Only daytime images for MODIS Aqua Reflectance bands 8-16 for H10V6 and H10V5 were downloaded and used to create the geoTIFF images for each storm. These are seasonal data for storms from 2001-2008, and cover the following named storms:
The following example shows how to cite the use of this dataset in a publication. For more information, please see our Citing GHRC DAAC and Data page.
. 2010. Sediment Analysis Network for Decision Support (SANDS) MODIS Geotiff [indicate subset used]. Dataset available online [http://ghrc.nsstc.nasa.gov/] from the NASA EOSDIS Global Hydrology Resource Center Distributed Active Archive Center, Huntsville, Alabama, U.S.A. doi: http://dx.doi.org/10.5067/SANDS/MODIS/DATA101
Campaign
The purpose of the Sediment Analysis Network for Decision Support (SANDS) project was to address sediment redistribution issues by producing a suite of decision support products, derived from satellite observations from MODIS, Landsat, and SeaWiFS instruments, for assessment and monitoring of suspended sediment and sediment deposition in the north central Gulf of Mexico region. These products are now available to support resource management, planning, and decision making activities in the Gulf of Mexico. The SANDS project is a collaborative project between the Geological Survey of Alabama (GSA) and the University of Alabama in Huntsville Information Technology Systems Center and is funded through the NASA Applied Sciences Program ROSES A.28. The project's purpose was to produce an image showing enhanced suspended sediment from satellite data captured before and after tropical cyclones in the north central Gulf of Mexico between 2000 and 2009. More information about the SANDS project can be found here http://projects.itsc.uah.edu/sands/index.html.
Instrument Description
The Moderate Resolution Imaging Spectroradiometer (MODIS) is a multi-disciplinary, keystone instrument on Aqua and Terra, providing a wide array of multispectral, daily observations of land, ocean, and atmosphere features at spatial resolutions between 250 m and 1000 m. Approximately 40 data products are produced from the MODIS data. Data are distributed not only through the EOS Data and Information Service (EOSDIS) Distributed Active Archive Centers (DAACs) at Goddard Space Flight Center, the EROS Data Center in Sioux Falls, South Dakota, and the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado, but also via over 100 Direct Broadcast (DB) stations distributed world-wide.
Aqua:
Aqua (EOS PM-1) is a multi-national NASA scientific research satellite in orbit around the Earth, studying the precipitation, evaporation, and cycling of water. It is the second major component of the Earth Observing System (EOS) preceded by Terra (launched 1999). The satellite was launched from Vandenberg Air Force Base on May 4, 2002, aboard a Delta II rocket. Aqua is on a Sun-synchronous orbit. Aqua carries 6 instruments: AMSR-e, MODIS, AMSU-A, AIR, HSB, CERES.
Terra:
Terra (EOS AM-1) is a multi-national NASA scientific research satellite in a sun-synchronous orbit around the Earth. It is the flagship of the Earth Observing System (EOS). The satellite was launched from Vandenberg Air Force Base on December 18, 1999, aboard an Atlas IIAS vehicle and began collecting data on February 24, 2000. Terra carries a payload of five remote sensors designed to monitor the state of Earth's environment and ongoing changes in its climate system: ASTER, CERES, MISR, MODIS, MOPITT.
Investigators
Sandy M. Ebersole, PhD
Geological Survey of Alabama
P.O. Box 869999
Tuscaloosa, Alabama 35486-6999
File Naming Convention
These data products were produced from MODIS Level 1B data containing calibrated and geolocated at-aperture radiances. More about these data can be found here MOD021KM and here Specification.
GeoTIFF and HDF-EOS-Subset files are named with the following convention:
********.YYYYDDD.HHMM.VVV.YYYYDDDHHMMSS.xxx
Where,
******** = earth science data type name
YYYYDDD = year and julian date
HHMM = hour and minute start time (UTC)
VVV = collection version
YYYYDDDHHMMSS = production date and time (UTC)
xxx =file type (.hdf, .tif, or .met)
GSA files are organized by storm and are named with the following conventions:
SE_Xyyyymmdd_[storm name].jpg
SE_Xyyyymmdd_[storm name].pdf
SE_Xyyyymmdd_[storm name].txt
Zipped_grid_Xyyyymmdd_[storm name].zip
Where,
SE = GSA enhanced sediment file
X = Satellite (T= Terra, A= Aqua)
yyyymmdd = year, month, and day of the data
[storm name] = storm associated with the data
.jpg = image file with the GSA stacked image
.pdf = pdf version of jpg image
.txt = metadata file
.zip = zipped ArcGIS grid files
Data Format
The subsetted MODIS files have a one to one correspondence with MODIS level 1B files, usually only one file per day. These subsetted files are in HDF-EOS (Hierarchical Data Format - Earth Observing System). HDF-EOS is a standard format to store data collected from EOS satellites: Terra, Aqua, and Aura.
The GeoTIFF image files also have a one to one correspondence with subsetted files, one for each of the MODIS overpass files, which have approximately a 5 min time period. These image files are in GeoTIFF format. GeoTIFF refers to TIFF (Tagged Image File Format) files which have geographic (or cartographic) data embedded as tags within the TIFF file. The geographic data can then be used to position the image in the correct location and geometry on the screen of a geographic information display. The TIFF file structure allows both the metadata and the image data to be encoded into the same file. GeoTIFF makes use of a public tag structure which is platform interoperable between any and all GeoTIFF-savvy readers.
The GSA files are available as PDF files and as JPEG image files. Zip files containing gridded ArcGIS files are also available.
Use Constraints
Reproduction or redistribution of digital datasets or products derived therefrom to a third party organization or entity is not forbidden. However, we do encourage any reproduction or hardcopy use of this data include and reference the GSA and ITSC SANDS project funded through the NASA Applied Sciences Program. User specifically agrees not to misrepresent this dataset, nor to imply that any changes made by the user were approved by the Geological Survey of Alabama. The Geological Survey of Alabama should be acknowledged as the originator of the data. This dataset is to be used as a primary reference source. This is public information and may be interpreted by organizations or others based on needs; however, users are responsible for the appropriate application. Federal, state, or local regulatory bodies are not to reassign to the originators any authority for decisions they make.
Contact Information
To order these data or for further information, please contact:
Global Hydrology Resource Center
User Services
320 Sparkman Drive
Huntsville, AL 35805
Phone: 256-961-7932
E-mail: ghrcdaac@itsc.uah.edu
Web: http://ghrc.nsstc.nasa.gov/
