NASA Landsat Data Collection Project/Campaign Document

NASA Landsat Data Collection, NLDC

Data collections from one or more sensors housed onboard various satellites in the Landsat series are contained in the NLDC data set. These data collections are the result of data acquisition requirements for several distinct projects including the GCLDC collection; the HTFP collection of source scenes and products; a collection of data from CENR (formerly CEES) historically referred to as the CEES collection; and ongoing NASA Landsat data purchases starting with the 1996 fiscal year.

The GCLDC collection contains Landsat TM scenes that were purchased by NASA from Space Imaging, formerly the Earth Observing Satellite Company (EOSAT), under a special agreement to promote the use of shared data in global change research. The HTFP, the largest component of NASA's Landsat Pathfinder Program, contains Landsat MSS and TM scenes collected over the past 20 years. The goal of the HTFP is to globally map deforestation in the humid tropical forests. The CEES collection is the result of an effort to coordinate data needs among several Federal agencies (e.g., Environmental Protection Agency, Department of the Interior agencies, National Oceanic and Atmospheric Administration, Department of Defense). These Landsat TM scenes were collected for a variety of research projects. Ongoing NASA purchases of Landsat TM data support NASA scientists and their affiliated researchers in programs and projects including the NASA Research and Applications Program; the Global Land Cover Test Sites Project (GLCTS); the Humid Tropical Forest Project; the International Biosphere-Geosphere Programme (IGBP), and the NASA Applications Program.

The NLDC scenes have been screened for cloud cover and band quality resulting in a high grade, high quality data compilation. Only the U.S. Government and its Affiliated Users (USGAU) may order NLDC-archive Landsat TM data with an acquisition date from 10 years old to the present. Otherwise, there are no order restrictions on either the Landsat MSS data or the Landsat TM data contained in the NLDC data set.

For a more general overview of Landsat data, see the following document:

• Landsat Satellites 1, 2, 3, 4, and 5 Data Set Document

The primary mission objective is to promote interdisciplinary global change studies by providing low cost or no cost data to researchers.

The NLDC's MSS and TM data are applicable to a broad range of disciplinary remote sensing projects (e.g., deforestation, pollution, ecological, and Earth science studies).

Data over a variety of coverage areas were selected for inclusion in the NLDC archive.

GCLDC Coverage Area (23 kb)

HTFP Coverage Area, Landsat Satellites 1, 2, and 3 (23 kb)

HTFP Coverage Area, Landsat Satellites 4 and 5 (23 kb)

CEES Coverage Area (23 kb)

Ongoing NASA Landsat Data Purchases Coverage Area: Data purchases are in the early stages. The largest portion of ongoing purchases is in support of, but not limited to, the Humid Tropical Forest Project (see the HTFP Coverage Area graphic).

The NLDC data set is comprised of four project components:

GCLDC: The GCLDC is the result of an agreement between NASA and Space Imaging, formerly EOSAT, which provided for the sharing of Landsat TM scenes for use in global change research. The GCLDC is comprised of an eclectic collection of scenes assembled to support a wide range of global change studies including projects from the Landsat Pathfinder Program. Additional non-GCLDC TM data may be available over the study areas, but different pricing and data usage restrictions may apply.

Though the GCLDC contains selected Landsat TM scenes with a temporal range from 1984 to 1993, the bulk of the collection's scenes range from 1989 to 1992.

The GCLDC TM scenes covering tropical forest regions in Brazil, central Africa, and Indonesia were collected for a single epoch to study deforestation utilizing geographic information system (GIS) technology. Other regional studies requiring data for a single epoch included a study of older forest growth in the Pacific Northwest; a study to determine pollution damage to forest sites in eastern Europe; and a study of arid regions in Africa including the Sahel.

Data collected over the Russian Boreal Forest provided multitemporal coverage for studying pollution damage. In addition, Landsat TM data provided multitemporal coverage for study over National Science Foundation (NSF) Long-Term Ecological Research (LTER) sites; for NASA field experiments; and for test sites from a preliminary listing of coverages compiled by the Moderate Resolution Imaging Spectrometer (MODIS) science team to be used as a base for future EOS Program studies.

Test sites for the EOS Program were selected over every Continent, and portions of the data collected over some of these test sites reside in the GCLDC archive. These data may be used for a variety of land cover and land use applications. The original purpose for the collection of test-site data was for the validation of algorithms to be used for processing MODIS and other EOS data with the plan that these data also could be used as part of ongoing studies by the remote sensing data user community (e.g., studies from the IGBP or NSF's LTER program which was established to conduct and facilitate long-term ecological research in the United States in order to further the understanding of general ecological phenomena which occur over long temporal and broad spatial scales; to document long-term experiments and observations; to conduct major synthesis and theoretical efforts; and to provide information for the identification and solution of societal problems).

HTFP: The amount of carbon held in terrestrial ecosystems has changed as a result of direct human effects of land use (e.g., deforestation) and indirect human effects on ecosystems (e.g., increased concentrations of atmospheric carbon dioxide or climate change). These direct and indirect human effects influence changes in ecosystem metabolism. At the present time, the net flux of carbon between the biota and atmosphere due to land use change (deforestation) can be calculated with more confidence than changes in carbon storage associated with large-scale changes in ecosystem metabolism. This is because of the large difference in biomass between forests and the agricultural systems which replace them and because deforestation and reforestation can be readily documented and quantified (particularly if utilizing remote sensing data).

Most of the world's deforestation has occurred in the following regions: the Amazon Basin, central Africa, and southeast Asia. Mapping deforestation in these three areas accounts for the majority of deforestation activities taking place in closed tropical forests worldwide and accounts for approximately 75 to 80 percent of the current net biotic flux of carbon.

As the largest component of NASA's Landsat Pathfinder Program, the HTFP contains Landsat MSS and TM scenes collected over approximately the last 20 years with the goal to globally map deforestation in the tropical forests. The focus of the project is: (1) to use Landsat data to map deforestation in closed tropical forests at a sub-kilometer resolution for a base period (e.g., 1986); (2) to use Landsat data to quantify and map the rate of deforestation by mapping the change from other time periods (e.g., 1975, 1992); and (3) to create a Landsat data set, to provide science products for distribution in a digital GIS format, and to develop an information management system (IMS) to manage data orders, data archiving, product processing, and product distribution.

The HTFP is a collaborative project between the Institute for the Study of Earth, Oceans, and Space at the University of New Hampshire; the Department of Geography at the University of Maryland; and NASA's Goddard Space Flight Center. Part of NASA's Earth Science Enterprise (ESE) program and the Earth Observing System Data and Information System (EOSDIS) initiative, funding for HTFP is provided predominantly by NASA with support from the Environmental Protection Agency and from the U.S. Geological Survey's National Mapping Division.

The two university laboratories manage the project and perform the analyses. The University of Maryland is primarily responsible for geographic coverage and analysis of data covering non-Brazilian Amazon areas and areas in central Africa. The University of New Hampshire is primarily responsible for geographic coverage and analysis of data covering areas in the Brazilian Amazon and southeast Asia. The University of New Hampshire also is responsible for selecting, ordering, and archiving project data and for managing all preprocessing of the data. The U.S. Geological Survey's Earth Resources Observation and Science Center provides preprocessing support and provides MSS data from the National Satellite Land Remote Sensing Data Archive.

CEES: The CENR, formerly CEES, is a committee that coordinates activities of the U.S. Global Change Research Program (USGCRP). The focus of the USGCRP is the scientific study of the Earth system and its components including global change research. This research contributes to fundamental scientific knowledge; improves the capabilities for documenting and assessing potential changes in the Earth system and the implications of those changes; and assists in the development of improved predictions of events.

The CEES collection is comprised of Landsat TM data with a temporal range from 1986 to 1994, and is the result of an effort to coordinate data needs among several Federal agencies (e.g., Environmental Protection Agency, Department of the Interior agencies, National Oceanic and Atmospheric Administration, Department of Defense). These Landsat TM scenes were collected for a variety of research projects.

Ongoing NASA Landsat Data Purchases: The newest component of the NLDC data set, the ongoing purchases of Landsat TM data support NASA scientists and their affiliated researchers in programs and projects such as NASA research and applications programs and the IBGP. The GLCTS and the HTFP comprise the two largest components of this ongoing data collection effort. The GLCTS project resulted in the development of a multitemporal data set of satellite imagery for a globally distributed set of test sites. Designed as a resource for research on land cover characterization and for the testing of algorithms for NASA's Earth Observing System (EOS), GLCTS data set development is coordinated with a number of affiliated organizations. These test sites represent a wide range of land cover types and are well characterized on the ground. The goal is to have approximately 40 to 80 sites developed for broad land cover representation. The other of these two components, the HTFP, is described above.

Data purchases are in the early stages with the largest portion of ongoing purchases in support of, but not limited to, the Humid Tropical Forest Project.

Landsat Multispectral Scanner Data
Landsat Thematic Mapper Data

NLDC Data Processing: Processing levels for the Landsat data vary (i.e., one or more of the following levels may or may not be applicable to scenes contained in any of the four components of the NLDC data set. Field descriptors follow for the possible processing levels as they may appear in the IMS inventory results (NLDC data are only distributed at their current processing level).

• Raw: Uncorrected, radiometrically and geometrically raw. Scan lines reversed and nominally aligned.



• Radiometrically Corrected: Calibration applied. Scan lines reversed and nominally aligned.



• Systematically Corrected: Radiometrically and geometrically corrected using the satellite model and platform/ephemeris information. Rotated and aligned to the user-defined map projection.



• Precision Corrected: Radiometrically and geometrically corrected using the satellite model and platform/ephemeris information. Rotated and aligned to the user-defined map projection using ground control points to improve the satellite model.



• Terrain Corrected: Radiometrically and geometrically corrected using the satellite model and platform/ephemeris information. Rotated and aligned to the user-defined map projection using ground control points and digital terrain model to improve the satellite model and to remove the geodetic inaccuracy caused by the parallax error that occurs because of local terrain elevation.

Component-Specific Data Processing Information:

• GCLDC-Specific NLDC Data Processing: The GCLDC consists of systematically corrected Landsat TM data in Fast format.



• HTFP-Specific NLDC Data Processing: The HTFP collection of source scenes and products involve two types of processing for distribution:



1. HTFP SOURCE SCENES: Source scenes were acquired from Space Imaging [TM data in Fast format]; the National Land Remote Sensing Data Archive (NSLRSDA) [MSS data in either EROS Digital Image Processing System (EDIPS) format or CCT-X format]; the Thailand Remote Sensing Center [MSS and TM data]; and Brazil's Instituto Nacional de Pesquisas Espaciais (INPE) [TM data]. The HTFP data are systematically corrected except for NSLRSDA MSS data in the CCT-X format and Thailand Remote Sensing Center MSS data. Copies of source scenes are distributed in their native formats (i.e., no additional processing is applied to these archive data).



2. HTFP PRODUCTS: Products are systematically corrected and have tic marks digitally embedded in the zero-filled areas outside of the valid image data area. These tic marks are annotated with Universal Transverse Mercator (UTM) coordinates, which in turn are calculated using the georeferencing information contained in the header records on the source tape.
• CEES-Specific NLDC Data Processing: The CEES collection consists of systematically corrected Landsat TM data in Fast format.



• Ongoing Landsat Data Purchases-Specific NLDC Data Processing: The ongoing purchases consist of Landsat TM data purchased from Space Imaging, the NSLRSDA, or foreign ground stations. These data are distributed in their native formats (i.e., no additional processing has been applied to these archive data). Since these data are purchased by a large and diverse group of Principal Investigators, data characteristics (e.g., projections, resampling techniques) are not necessarily consistent.

Map Projections Information:

See the following Map Projection Parameters tables for an explanation of correlations between projection parameters and map projections (NLDC data are only distributed as currently projected).

Map Projection Parameters: Elements 1 through 15

Code	Projection Name	Array Element
		1	2	3	4	5	6	7	8	9	10	11	12	13
0	Geographic
1	UTM	SMajor	SMinor
2	State Plane
3	Albers Equal Area	SMajor	SMinor	STDPR1	STDPR2	CentMer	OriginLat	FE	FN
4	Lambert Conform. Con.	SMajor	SMinor	STDPR1	STDPR2	CentMer	OriginLat	FE	FN
5	Mercator	SMajor	SMinor			CentMer	TrueScale	FE	FN
6	Polar Stereographic	SMajor	SMinor			LongPol	TrueScale	FE	FN
7	Polyconic	SMajor	SMinor			CentMer	OriginLat	FE	FN
8	Equid. Conic A	SMajor	SMinor	STDPAR		CentMer	OriginLat	FE	FN	zero
8	Equid. Conic B	SMajor	SMinor	STDPR1	STDPR2	CentMer	OriginLat	FE	FN	one
9	Transverse Mercator	SMajor	SMinor	Factor		CentMer	OriginLat	FE	FN
10	Stereographic	Sphere				CentLon	CenterLat	FE	FN
11	Lambert Azimuthal	Sphere				CentLon	CenterLat	FE	FN
12	Azimuthal Equidistant	Sphere				CentLon	CenterLat	FE	FN
13	Gnomonic	Sphere				CentLon	CenterLat	FE	FN
14	Orthographic	Sphere				CentLon	CenterLat	FE	FN
15	Gen. Vert. Near Per.	Sphere		Height		CentLon	CenterLat	FE	FN
16	Sinusoidal	Sphere				CentMer		FE	FN
17	Equirectangular	Sphere				CentMer	TrueScale	FE	FN
18	Miller Cylindrical	Sphere				CentMer		FE	FN
19	Van der Grinten	Sphere				CentMer	OriginLat	FE	FN
20	Hotin Oblique Merc. A	SMajor	SMinor	Factor			OriginLat	FE	FN	Long1	Lat1	Long2	Lat2	zero
20	Hotin Oblique Merc. B	SMajor	SMinor	Factor	AziAng	AzmthPt	OriginLat	FE	FN					one
21	Robinson	Sphere				CentMer		FE	FN
22	Space Oblique Merc. A	SMajor	SMinor		IncAng	AscLong		FE	FN	PSRev	LRat	PFlag		zero
22	Space Oblique Merc. B	SMajor	SMinor	Satnum	Path			FE	FN					one
23	Alaska Conformal	SMajor	SMinor					FE	FN
24	Goodes Homolosine	Sphere
25	Mollweide	Sphere				CentMer		FE	FN
26	Interrupt Mollweide	Sphere
27	Hammer	Sphere				CentMer		FE	FN
28	Wagner IV	Sphere				CentMer		FE	FN
29	Wagner VII	Sphere				CentMer		FE	FN
30	Oblated Equal Area	Sphere		Shapem	Shapen	CentLon	CenterLat	FE	FN	Angle

Where the Parameters used above are defined by the following:

NOTES:

Array elements 14 and 15 are set to zero.
All array elements with blank fields are set to zero.
All angles (latitudes, longitudes, azimuths, etc.) are entered in packed degrees/minutes/seconds (DDDMMMSSS.SS) format.

The following notes apply to the Space Oblique Mercator A projection.

• A portion of Landsat rows 1 and 2 may also be seen as parts of rows 246 or 247. To place these locations at rows 246 or 247, set the end of path flag (parameter 11) to 1--end of path. This flag defaults to zero.

  When Landsat-1, -2, -3 orbits are being used, use the following values for the specified parameters:

    Parameter 4    099005031.2
    Parameter 5    128.87 degrees - (360/251 * path number) in packed DMS format
    Parameter 9    103.2669323
    Parameter 10   0.5201613
  

  When Landsat-4, -5 orbits are being used, use the following values for the specified parameters:

    Parameter 4    098012000.0
    Parameter 5    129.3 degrees - (360/233 * path number) in packed DMS format
    Parameter 9    98.884119
    Parameter 10   0.5201613
  

The NLDC data set is comprised of Landsat MSS and Landsat TM data purchased by NASA in support of numerous NASA-funded investigations. Landsat TM data purchased from Space Imaging and for which the image acquisition date is equal to or less than 10 years old are subject to restricted distribution. The U.S. Government and its Affiliated Users (USGAU) may acquire these NLDC-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 are not acceptable. The restricted distribution form only needs to be submitted once in order to establish eligibility for acquiring these data. Subsequent orders may be placed, and Customer User Services will verify that an original restricted distribution form is on file.

See Contact Information.

Data are distributed by the Earth Resources Observation and Science Center for a cost.