SPOT - North American Data Buy

The USGS has contracted with SPOT Image Corporation to acquire and provide Satellite Pour l'Observation de la Terre (SPOT) satellite data for November 2009 through January 2013. Under the North America Data Buy (NADB) agreements, SPOT Image will provide moderate-resolution data from their SPOT 4 and 5 satellites over the conterminous United States and parts of Canada and Mexico through the receiving capabilities at the USGS EROS Center. The French space agency, Centre National d'Etudes Spatiales (CNES), owns and operates the SPOT satellite system. SPOT Image Corporation is a subsidiary of the SPOT Image group, which provides worldwide distribution of their imagery.

Under the licensing arrangements of the North America Data Buy contract, access is limited to U.S. Federal civil Government agency users and U.S. State and local government users. The 2011 contract expands usage to include U.S. tribal governments. Qualified users must be logged in to EarthExplorer to gain access to this dataset. An explanation of data restrictions and limitations is displayed when accessing these collections and must be agreed upon before gaining access to these data.

The USGS SPOT 4 and 5 datasets provide North American coverage between 53° north latitude and 23.5° north latitude in calendar year 2010. The coverage for 2011 extends from 55° north latitude to 23.5° north latitude.

Both SPOT satellites carry imaging instruments that operate with panchromatic and multispectral sensors. The SPOT 4 payload includes two High Resolution Visible and Infrared (HRVIR) sensors, and SPOT 5 utilizes two High Resolution Geometric (HRG) instruments. Each sensor has a swath of 60 km and has an oblique viewing capability of 27° on each side of vertical. The sensors can operate independently to observe separate targets or in tandem to cover a larger swath in a single pass. Each scene in this collection is approximately 60 km by 60 km and is referenced to World Geodetic System 84 (WGS 84) datum.

*near infrared (NIR) and shortwave infrared (SWIR)

**The resolution of the SPOT 5 multispectral scene is 10 m.

SPOT Products

All SPOT scenes acquired via the NADB are initially processed to Level 1A (L1A) by SPOT Image Corporation and are made accessible to authorized users through EarthExplorer. In addition to the L1A dataset, USGS EROS also offers Level 1Gst (L1Gst), Level 1T (L1T), Full Resolution Browse, and GIS Ready Bundle products.

• Standard Correction (Level 1A) provides corrections to compensate for radiometric variations due to detector sensitivity. This product is intended for users who wish to do their own geometric image processing. Digital Image Map (DIMAP) is the SPOT product data format.

DIMAP typically contains the following files:

IMAGERY.TIF = image file in GeoTIFF format
METADATA.DIM = XML metadata file
ICON.JPG = Image.icon
PREVIEW.JPG = Quicklook
STYLE.XSL = Style sheet used to apply HTML formatting to XML file

• Systematic Terrain Correction (Level 1Gst) provides radiometric and systematic geometric corrections, derived from spacecraft ephemeris data, while employing a 90-meter USGS Digital Elevation Model (DEM) for topographic accuracy. L1Gst scenes are available in GeoTIFF format.

• Standard Terrain Correction (Level 1T) provides radiometric and systematic geometric corrections by incorporating ground control points while employing a 90-meter USGS Digital Elevation Model (DEM) for topographic accuracy. Geodetic accuracy of the product depends on the accuracy of the ground control points and is expected to be within 2.5 pixels. Ground control points used for Level 1T correction come from the GLS2005 dataset. Scenes with sufficient ground control data for terrain correction are processed to Level 1T. Scenes that do not have adequate ground control will be processed to the best level of correction (Level 1Gst). L1T scenes are available in GeoTIFF format.
• Full Resolution Browse provides a full resolution image in JPEG format for scenes that have been processed to Level 1T.
• GIS Ready Bundle provides a full resolution image in JPEG format bundled with metadata and a world file to use in geographic information systems, image processing software, and web mapping applications. This option provides users with a georeferenced JPEG image and is only available for scenes that have been processed to Level 1T.

SPOT 4 and 5 products are available for download in both panchromatic and multispectral modes. A panchromatic scene is a single-band image, and a color product is derived from the multispectral bands. File sizes for L1A, L1Gst, and L1T images may vary from 30 to 250 megabytes (MB) depending on imaging mode and level of processing. File sizes for Full Resolution Browse and GIS Ready Bundle products may vary from 1 to 5 MB depending on imaging mode.

User Access

This collection of SPOT 4 and 5 data is subject to the terms and conditions stated in the North America Data Buy agreement between SPOT Image and the USGS.

Restrictions

• Users accessing the imagery affirm they are affiliated with a U.S. civil Government agency at the Federal, State, or local level. User affiliation extends to U.S. tribal government agencies and U.S. Government cooperators for data acquired after December 28, 2010. User affiliation extends to U.S. Government grant recipients for data acquired after June 30, 2012.
• For each dataset, a specific license/use agreement is provided with the data describing the terms and conditions; it is the responsibility of the user to adhere to these terms and conditions.
• Users accessing the imagery agree to use this imagery for noncommercial purposes only.
• Users will not use the imagery for purposes of monetary reward by means of the sale, resale, loan transfer, hire, or other form of commercial exploitation.
• Users may generate an unlimited number of hardcopies and softcopies of the data for their internal use.
• Users may permit those outside the licensed user group to see hardcopies or softcopies of the imagery, with appropriate copyright marks. However, softcopies of the imagery shall not be given to those outside the licensed user group.
• Users accessing the imagery may generate any derived product from the licensed data but need to acknowledge that this imagery remains the property of the CNES. Use of the data in published work shall be attributed to CNES and must retain the copyright: © CNES (date of image).
• The USGS will not be held responsible or liable for misuse or misrepresentation by the end users and is not required to enforce these provisions beyond communicating them to the user.

Registration

Qualified users are recognized through the EarthExplorer registration process and must be logged in to gain access to this dataset. Users must accept the restrictions stated in the End User License Agreement (EULA) in order to download data.