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All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

The first earth resources technology satellite /ERTS 1/

The present work describes the ERTS 1 spacecraft and data collection system and reviews the operation of the system since the satellite was launched in July, 1972. Perhaps the most significant result of the ERTS 1 mission is the realization that features related to land resources or to environmental processes can be mapped synoptically for very large areas on scales up to 1:250,000 without substantial loss of definition. Examples of color composite images obtained by ERTS 1 are shown.

Nordberg, W.↗
NASA NTRS1974

Exploration for fossil and nuclear fuels from orbital altitudes

Results from the ERTS program pertinent to exploration for oil, gas, and uranium are discussed. A review of achievements in relevant geological studies from ERTS, and a survey of accomplishments oriented towards exploration for energy sources are presented along with an evaluation of the prospects and limitations of the space platform approach to fuel exploration, and an examination of continuing programs designed to prove out the use of ERTS and other space system in exploring for fuel resources.

Short, N. M.↗
NASA NTRS1974

Evaluation of satellite remote sensing and automatic data techniques for characterization of wetlands and coastal marshlands

The author has identified the following significant results. The evaluation was conducted in a humid swamp and marsh area of southern Louisiana. ERTS digital multispectral scanner data was compared with similar data gathered by intermediate altitude aircraft. Automatic data processing was applied to several data sets to produce simulated color infrared images, analysis of single bands, thematic maps, and surface classifications. These products were used to determine the effectiveness of satellites to monitor accretion of land, locate aquatic plants, determine water characteristics, and identify marsh and forest species. The results show that to some extent all of these can be done with satellite data. It is most effective for monitoring accretion and least effective in locating aquatic plants. The data sets used show that the ERTS data is superior in mapping quality and accuracy to the aircraft data. However, in some applications requiring high resolution or maximum use of intermittent clear weather conditions, data gathering by aircraft is preferable. Data processing costs for equivalent areas are about three times greater for aircraft data than ERTS data. This is primarily because of the larger volume of data generated by the high resolution aircraft system.

Cartmill, R. H.↗
NASA NTRS1975

Geological applications of LANDSAT-1 imagery to the Great Salt Lake area

The ERTS program has been designed as a research and development tool to demonstrate that remote sensing from orbital altitudes is a feasible and practical approach to efficient management of earth resources. From this synoptic view and repetitive coverage provided by ERTS imagery of the Great Salt Lake area, large geological and structural features, trends, and patterns have been identified and mapped. A comparative analysis of lineaments observed in September and December data was conducted, existing mineral locations were plotted, and areas considered prospective for mineralization based on apparent structure-mineralization relationships were defined. The additional information obtained using ERTS data provides an added source of information to aid in the development of more effective mineral exploration programs.

Anderson, A. T.↗
NASA NTRS1975

A study of atmospheric effects on pattern recognition devices

The author has identified the following significant results. ERTS-1 imagery can be applied in the broadscale assessment of forest resources as a supplement to aerial photography and field survey. There was no application to inventory of crop and pasture diseases mainly because of poor quality and low resolution, and unreliability of image acquisition. Inventory of soil erosion was satisfactory in humid eastern New South Wales, but not in semi-arid areas. Patterns of snow cover, areas of water in natural and artificial water bodies, extent of bushfires, and location of coastal mobile sand bodies were readily apparent. ERTS-1 imagery was judged to be a valuable addition to conventional techniques of regional small scale geological mapping. ERTS data was successfully used to map flooding and flood progression. The imagery was found suitable for mapping at 1:1,000,000 scale both on the mainland and in Antarctica, but did not meet accuracy specifications for 1:250,000 mapping.

Thomson, F. J.↗
NASA NTRS1974

The economic impact of remote sensing data as the source of nonpoint pollution monitoring and control

Nonpoint pollution of streams with sediment as a result of runoff from alternative uses of land has become a socially unacceptable product of economic activity. This report describes a research approach to economically achieve correction of the nonpoint pollution problem. The research approach integrates the economic model with those data which may be obtainable from remotely sensed sources. The economic problem involves measurement of the direct benefits and costs associated with the changes in land management activities necessary to reduce the level of nonpoint pollution. Remotely sensed data from ERTS-1 may provide some of the information required for the economic model which indicates efficient solutions to the nonpoint pollution problem. Three classes of data (i.e., soil categories, vegetative cover, and water turbidity) have the potential to be measured by ERTS-1 systems. There is substantial research which indicates the ability of ERTS-1 to measure these classes of data under selected conditions.

Miller, W. L.↗
NASA NTRS1975

A multilevel multispectral data set analysis in the visible and infrared wavelength regions

Skylab multispectral scanner data, digitized Skylab color infrared (IR) photography, digitized Skylab black and white multiband photography, and Earth Resources Technology Satellite (ERTS) multispectral scanner data collected within a 24-hr time period over an area in south-central Indiana near Bloomington on June 9 and 10, 1973, were compared in a machine-aided land use analysis of the area. The overall classification performance results, obtained with nine land use classes, were 87% correct classification using the 'best' 4 channels of the Skylab multispectral scanner, 80% for the channels on the Skylab multispectral scanner which are spectrally comparable to the ERTS multispectral scanner, 88% for the ERTS multispectral scanner, 83% for the digitized color IR photography, and 76% for the digitized black and white multiband photography. The results indicate that the Skylab multispectral scanner may yield even higher classification accuracies when a noise-filtered multispectral scanner data set becomes available in the near future.

Biehl, L. L.↗
NASA NTRS1974

Improvement of water resources management through the use of satellites flood plain delineation

The delineation of flood-prone areas is an important activity in several parts of the world. Conventional methods map the topography surrounding the river via ground surveys and supplementary aerophotography. The conventional method costs approximately $2,000 per river-kilometer, is laborious and time-consuming. ERTS information can supplement this method by two complementary techniques: (1) the dynamic method images the floods as they occur, exploiting the fact that visible evidence of inundation remains for a substantial period after the high waters have receded; (2) the static method utilizes the fact that several flood plains have been found recognizable on ERTS imagery from distinctive, permanent indicators left by previous floods. For areas whose full development is still in the future, the dynamic method allows the gradual buildup with time of a flood plain map, by simply correlating existing ERTS imagery. The static method allows in several areas, a first-cut indication, of proneness to floods.

Castruccio, P. A.↗
NASA NTRS1974

Ice growth in Duluth harbor and western Lake Superior

Ice growth computation for the Duluth-Superior harbor and the adjacent Lake Superior waters, using the heat budget balance, agrees well with the measured ice values for the 1972-73 winter season. ERTS data is used for the determination of ice albedo and the resulting ice decay rate on Lake Superior. During the period of ice packing near Duluth, the calculated ice decay rates, combined with the ERTS data on the extent and the condition of the ice field indicate maximum ice packing between March 20-27, when the packed ice field, exhibiting albedo values above 70% reached an average 60 cm thickness. The results offer a method for description of ice packing which could be used for ice forecasting on Lake Superior if more frequent ERTS images were available.

Sydor, M.↗
NASA NTRS1974

Atmospheric correction of remotely sensed spacecraft data

A model designed to predict the transfer of radiative energy in the earth atmosphere is described. The computational procedure accounts for absorption and scattering processes at visible and near infrared wavelengths. This paper reports on application of the atmospheric model to the interpretation of ERTS Multispectral Scanner (MSS) data. Spectrally-averaged values of the radiance emerging at the top of the atmosphere are computed for each MSS Band. It is concluded that ERTS MSS Band 4 data are to a high degree influenced by the water vapor content of the atmospere. Knowledge of the meteorological conditions at the time of an ERTS overpass appears to be necessary in order to achieve maximum classification accuracy. The impact of this conclusion upon the accuracy of identification of surface features will next be determined.

Jurica, G. M.↗
NASA NTRS1975

Earth resources satellite systems for flood monitoring

The environmental satellites NOAA-2 and ERTS-1 observed flooding in United States' rivers such as the Mississippi during 1973. Combination of NOAA-2 observation frequency and the ERTS-1 resolution provides an adequate satellite system for monitoring floods. Several polar-orbiting satellites of the ERTS type could view flooded areas at a reasonably high resolution every three to five days. A high-resolution earth-synchronous satellite would further enhance flood mapping by providing observations whenever clouds are absent.

Mcginnis, D. F.↗
NASA NTRS1975

A study to explore the use of orbital remote sensing to determine native arid plant distribution

The author has identified the following significant results. Research results include a method for determining the reflectivities of natural areas from ERTS data taking into account sun angle and atmospheric effects on the radiance seen by the satellite sensor. Ground truth spectral signature data for various types of scenes, including ground with and without annuals, and various shrubs were collected. Large areas of varnished desert pavement are visible and mappable on ERTS and high altitude aircraft imagery. A large scale and a small scale vegetation pattern were found to be correlated with presence of desert pavement. A comparison of radiometric data with video recordings shows quantitatively that for most areas of desert vegetation, soils are the most influential factor in determining the signature of a scene. Additive and subtractive image processing techniques were applied in the dark room to enhance vegetational aspects of ERTS.

Mcginnies, W. G.↗
NASA NTRS1975

NASA crop calendars: Wheat, barley, oats, rye, sorghum, soybeans, corn

Crop calenders used to determine when Earth Resources Technology Satellite ERTS data would provide the most accurate wheat acreage information and to minimize the amount of ground verified information needed are presented. Since barley, oats, and rye are considered 'confusion crops, i.e., hard to differentiate from wheat in ERTS imagery, specific dates are estimated for these crops in the following stages of development: (1) seed-bed operation, (2) planting or seeding, (3) intermediate growth, (4) dormancy, (5) development of crop to full ground cover, (6) heading or tasseling, and flowering, (7) harvesting, and (8) posting-harvest operations. Dormancy dates are included for fall-snow crops. A synopsis is given of each states' growing conditions, special cropping practices, and other characteristics which are helpful in identifying crops from ERTS imagery.

Stuckey, M. R.↗
NASA NTRS1976

The use of LANDSAT-1 imagery in mapping and managing soil and range resources in the Sand Hills region of Nebraska

The author has identified the following significant results. Evaluation of ERTS-1 imagery for the Sand Hills region of Nebraska has shown that the data can be used to effectively measure several parameters of inventory needs. (1) Vegetative biomass can be estimated with a high degree of confidence using computer compatable tape data. (2) Soils can be mapped to the subgroup level with high altitude aircraft color infrared photography and to the association level with multitemporal ERTS-1 imagery. (3) Water quality in Sand Hills lakes can be estimated utilizing computer compatable tape data. (4) Center pivot irrigation can be inventoried from satellite data and can be monitored regarding site selection and relative success of establishment from high altitude aircraft color infrared photography. (5) ERTS-1 data is of exceptional value in wide-area inventory of natural resource data in the Sand Hills region of Nebraska.

Seevers, P. M.↗
NASA NTRS1975

Evaluation of Skylab data for land use mapping

Skylab multispectral scanner data, digitized Skylab color IR photography, digitized Skylab black and white multiband photography, and Earth Resources Technology Satellite (ERTS) multispectral scanner data collected within a twenty-four hour time period over an area in south-central Indiana near Bloomington on June 9 and 10, 1973, were compared in a machine-aided land use analysis of the area. The overall classification performance results, obtained with nine land use classes were 87% correct classification using the 'best' 4 channels of the Skylab multispectral scanner, 80% for the channels on the Skylab multispectra scanner, which are spectrally comparable to the ERTS multispectral scanner, 88% for the ERTS multispectral scanner, 83% for the digitized color IR photography, and 76% for the digitized black and white multiband photography. The results indicate that the Skylab multispectral scanner may yield even higher classification accuracies when a noise filtered multispectral scanner data set becomes available in the near future.

Biehl, L. L.↗
NASA NTRS1974

Land use mapping and modelling for the Phoenix Quadrangle

The author has identified the following significant results. The mapping of generalized land use (level 1) from ERTS 1 images was shown to be feasible with better than 95% accuracy in the Phoenix quadrangle. The accuracy of level 2 mapping in urban areas is still a problem. Updating existing maps also proved to be feasible, especially in water categories and agricultural uses; however, expanding urban growth has presented with accuracy. ERTS 1 film images indicated where areas of change were occurring, thus aiding focusing-in for more detailed investigation. ERTS color composite transparencies provided a cost effective source of information for land use mapping of very large regions at small map scales.

Place, J. L.↗
NASA NTRS1978

Mare Crisium area topography - A comparison of earth-based radar and Apollo mapping camera results

An earth-based radar topography (ERT) map has been constructed of the Mare Crisium area. Systematic and random sources of error are discussed. A comparison between the ERT map and Lunar Topographic Orthophotomaps shows a random mean discrepancy of less than 100 m between the two maps, except for small-scale (20 km or less in diameter) features, where systematic smoothing reduces the ERT elevation contrast

Zisk, S.↗
NASA NTRS1987

Directional thermal infrared exitance distributions of a deciduous forest in summer

Directional measurements of effective radiant temperatures (ERT) were made from a rotating mount suspended above an Oak-Hickory canopy. A directional ERT distribution is presented showing fairly weak trends with view angle. Additional data are presented to illustrate the character of spatial variations of ERT as a function of view and sun angle.

Balick, Lee K.↗

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