1. Project/Campaign Overview:
Name of Project/Campaign:
- Global Land Cover Test Sites, GLCTS
Project/Campaign Introduction:
The GLCTS project is an effort to develop a multitemporal satellite data base for a suite of globally distributed test sites to support research on land cover characterization and to support the testing and validation of improved algorithms for the Earth Observing System (EOS). The selected test sites represent a wide range of global land cover types, are well characterized on the ground, have ongoing field-based monitoring programs, and are of interest to the international global change research community (McGwire and Mah, 1996).
The primary component of the GLCTS data set is Landsat data, both multispectral scanner (MSS) data and thematic mapper (TM) data. In addition, a series of daily Advanced Very High Resolution Radiometer (AVHRR) 1-km data acquisitions, digital elevation model (DEM) data (i.e., in some instances, digital terrain elevation data (DTED)), and land cover information is included for the sites.
For a more general overview of AVHRR and Landsat data, see the following documents:
Project/Campaign Mission Objectives:
- In keeping with the mission of Pathfinder project activities, the GLCTS project helps to provide experience with which to develop the EOS data and information system for NASA's Earth Science Enterprise initiative.
Discipline(s):
- The GLCTS data sets constitute a unique data base with which to investigate multidisciplinary issues related to land use/land cover changes, human interactions with the environment, and numerous land processes studies.
Geographic Region(s):
An ongoing effort, it is anticipated that the GLCTS data set will contain between 40 and 60 test sites.
For further information on individual test sites, see Test Site Availability.
For further information on site-selection criteria, see the NASA Landsat Pathfinder Program Global Land Cover Test Sites Project Web site.
Detailed Project/Campaign Description:
The availability of data over a series of globally selected test sites, representing a wide range of land cover types, enhances the ability of the science community to address research issues associated with land cover and terrestrial ecosystem processes. Issues include the need to develop regional- and global-scale land cover assessments and to develop improved algorithms for land surface parameterization. Representative test sites also provide data sets with a high spatial resolution for use in the development of models that describe the land's surface and describe interactions between the land and the atmosphere. With data spanning from the early 1970's through the EOS era with Landsat 7 data, the Landsat Pathfinder program is anticipated to provide one of the longest records of high resolution remotely sensed data. The GLCTS project supports this effort.
Many of the existing digital, global land cover data sets have been compiled from vegetation maps that were created by using different methods, classification schemes, and temporal windows. In addition, there is also disagreement in the distribution of land covers among the existing maps (Townshend and others, 1991). Consequently, comprehensive and consistent land cover maps at regional and global scales are needed to improve the accuracy of the land cover stratifications used in global climate and biogeochemical process models and in regional water, vegetation, and energy studies (IGBP, 1992). Global, high-resolution test site data will contribute to the generation and assessment of land cover data sets.
Development of globally applicable techniques for direct parameterization necessitates complementary development and testing of procedures over a range of well characterized environmental conditions. Because of the intensive nature of the measurements required to fully develop these techniques, a test site approach is requisite. Also, before algorithms for surface parameter definition can be globally applied, they need to be tested at a number of locations representing different surface conditions, thus, the selection of test sites.
GLCTS Data Set Components: The GLCTS project is designed for implementation in two phases. Phase 1 is currently under way and focuses on the distribution of minimually processed data. Phase 2 is anticipated to provide value added enhancements for individual GLCTS data sets (Desert Research Institute, 1996).
Five components comprise the final phase GLCTS data sets including metadata, Landsat data, AVHRR 1-kilometer data, DEM data, and land cover information.
- Metadata: As part of individual GLCTS data sets, users are provided with metadata including the location and a description of each site; contact information for each site's principal investigator; information on other site-related data bases; a listing of all available Landsat data, excluding Landsat Ground Stations Working Group (LGSOWG) foreign Landsat data, over each site from the holdings of the National Satellite Land Remote Sensing Data Archive (NSLRSDA); and information on the format and size of each data element comprising a GLCTS data set.
- Landsat Data: Scenes selected from Landsat MSS data archives, which range from the 1970's to the 1990's, and scenes selected from Landsat TM data archives, which range from the 1980's to the 1990's, represent one of the components of GLCTS data sets.
- AVHRR Data: Covering a 500-km by 500-km area, a daily 1-km AVHRR data window is centered over each site.
- DEM Data: The DEM data are provided on a best-available basis.
- Land Cover Information: This information includes a synoptic land cover map as provided by the appropriate site investigator.
Data will be projected north up to a Universal Transverse Mercator (UTM) projection. The AVHRR time series data are registered to an enhanced Digital Chart of the World map base with an average root mean square error of 1.5 kilometers. The Landsat data are projected to a UTM projection using only satellite ephemeris data. Misregistration may occur up to 2.5 kilometers (Brenda Jones, oral commun., 1996).
2. Data Availability:
Data Type(s):
Landsat MSS Data
Landsat TM Data
AVHRR Data
DEM Data
DTED Data
Land Cover Information
Input/Output Media:
Proprietary Status:
Proprietary Landsat TM Data: Some site products contain data acquired under the terms of the U.S. Government and its Affiliated Users (USGAU) agreement, and members of USGAU may acquire these GLCTS-archive data provided that they complete and sign a restricted distribution form available through Customer Services. The original form must be completed and returned to Customer Services (facsimiles of signatures are not acceptable). The restricted distribution form only needs to be submitted once in order to establish eligibility for acquiring these Landsat TM data. Subsequent orders may be placed, and Customer Services will verify that an original restricted distribution form is on file.
Proprietary DTED Data: Sites containing DTED data covering Mexico were acquired from the Instituto Nacional de Estadistica, Geografia e Informatica (INEGI), and the distribution of these data is restricted. Only nonprofit organizations may acquire these data upon signing a restricted distribution form stating that the DEM data will be used for research purposes only and that the data will not be redistributed to any third parties. This form is available through LP DAAC User Services. A signed restricted distribution form must be mailed to Customer Services (facsimiles of signatures are not acceptable). This form only needs to be submitted once in order to establish eligibility for acquiring these DTED data. Subsequent orders may be placed, and the EDC DAAC User Services will verify that the restricted distribution form is on file.
Restricted Distribution Forms: The content of the forms for proprietary data vary depending upon the data type. Multiple forms may be required if a test site is covered by both proprietary Landsat TM data and Mexican DTED data.
3. Data Access:
Data Center Location:
See Contact Information.
Associated Costs:
Data are distributed by the EDC DAAC on 8-mm tapes at a cost of $45 per tape. It takes approximately six to eight tapes to hold a test site so the estimated cost per test site is between $90 and $120.
4. Principal Investigator Information:
Principal investigators vary by site (see Submitting Investigator Information).
5. Submitting Investigator Information:
6. References:
Evans, Gayla, Feistner, Kelly, and Larson, Charles, in press, Landsat Pathfinder processing support at the EROS Data Center [abs.], in Pecora Thirteen, Human Interactions with the Environment--Perspectives from Space, 13th, Sioux Falls, South Dakota, August 20-22, 1996, Proceedings: Bethesda, Maryland, American Society of Photogrammetry and Remote Sensing.
McGwire, Kenneth, and Mah G.R., in press, The NASA Pathfinder Global Land Cover Test Sites project, in Pecora Thirteen, Human Interactions with the Environment--Perspectives from Space, 13th, Sioux Falls, South Dakota, August 20-22, 1996, Proceedings: Bethesda, Maryland, American Society of Photogrammetry and Remote Sensing.
National Aeronautics and Space Administration, [1996], The NASA Pathfinder program--global land cover test sites project: Reno, Nevada, Desert Research Institute, electronic version, http://glcts.maxey.dri.edu/glcts/
Townshend, J.R.G., ed., 1992, Improved global data for land applications--a proposal for a new high resolution data set, report of the Land Cover Working Group of IGBP-DIS, Report No. 20: Stockholm, Sweden, International Council of Scientific Unions, International Geosphere-Biosphere Programme, 87 p.
Townshend, John, Justice, Christopher, Li, Wei, Gurney, Charlotte, and McManus, Jim, 1991, Global land cover classification by remote sensing--present capabilities and future possibilities: Remote Sensing of Environment, v. 35, nos. 2 and 3, p. 243-255.
7. Glossary of Terms:
8. List of Acronyms:
AVHRR -- Advanced Very High Resolution Radiometer
DAAC -- Distributed Active Archive Center
DEM -- Digital Elevation Model
DTED -- Digital Terrain Elevation Data
EDC -- EROS Data Center
EOS -- Earth Observing System
GLCTS -- Global Land Cover Test Sites
IGBP -- International Geosphere-Biosphere Programme
INEGI -- Instituto Nacional de Estadistica, Geografia e Informatica
LGSOWG -- Landsat Ground Stations Working Group
LP DAAC -- Land Processes Distributed Active Archive Center
LTER -- Long Term Ecological Research
MSS -- Multispectral Scanner
NASA -- National Aeronautics and Space Administration
NSLRSDA -- National Satellite Land Remote Sensing Data Archive
TM -- Thematic Mapper
URL -- Uniform Resource Locator
USGAU -- U.S. Government and its Affiliated Users
UTM -- Universal Transverse Mercator
EOSDIS Acronym List
9. Document Information:
Document Revision Date: January 28, 2004
Document Review Date: November 14, 1996
Document Curator: LP DAAC staff
Document URL:
http://eosims.cr.usgs.gov:5725/CAMPAIGN_DOCS/glcts_proj_camp.html