44,152 research outputs found

    Survey of users of earth resources remote sensing data

    Get PDF
    A user survey was conducted to determine current earth resources survey (ERS) data use/user status and recommendations for strengthening use. Only high-altitude aircraft and satellite (primarily LANDSAT) data were included. Emphasis was placed on the private sector/industrial user. Objectives of the survey included: who is using ERS data, how they are using the data, the relative value of current data use as well as obtaining user views as to possible ways of strengthening future ERS data use. The survey results are documented and should provide relevant decision making information for developing future programs of maximum benefit to all end users of satellite ERS data

    Third Earth Resources Technology Satellite Symposium. Volume 3: Discipline summary reports

    Get PDF
    Presentations at the conference covered the following disciplines: (1) agriculture, forestry, and range resources; (2) land use and mapping; (3) mineral resources, geological structure, and landform surveys; (4) water resources; (5) marine resources; (6) environment surveys; and (7) interpretation techniques

    Third ERTS Symposium: Abstracts

    Get PDF
    Abstracts are provided for the 112 papers presented at the Earth Resources Program Symposium held at Washington, D.C., 10-14 December, 1973

    Application of ERTS-1 data to integrated state planning in the state of Maryland

    Get PDF
    There are no author-identified significant results in this report

    Impervious Surface Mapping in Coastal New Hampshire (2005)

    Get PDF
    Estimates of impervious surface acreage in 2005 were generated and compared to prior estimates for 1990 and 2000 for a 48-town region in coastal New Hampshire, including the 42 towns within Zones A and B of the New Hampshire Estuaries Project (NHEP) area. The estimates were based on applying both traditional and subpixel image classification techniques to 30-meter Landsat 5 Thematic Mapper (TM) satellite data, acquired 3 October 2005. The classifications indicated that impervious surface acreage increased from 4.3% (31,233 acres) in 1990, to 6.3% (45,445 acres) in 2000, to 7.4% (53,408 acres) in 2005. At the subwatershed level, the Portsmouth Harbor subwatershed recorded the highest percentage of impervious surface acreage in 1990 with 19.8% coverage (2,310 acres) and in 2000 with 25.5% coverage (2,975 acres), and this finding continued in 2005 with 28.9% (3,364 acres) of the watershed mapped as impervious. An accuracy assessment was applied to the regional data, and indicated an accuracy of 98.3% for the 2005 data, which compared favorably with the assessment of the 1990 effort (98.6% correct) as well as the 2000 data (93.1% correct). These figures reflect the overall presence/absence of impervious surfaces within the randomly selected pixels. The accuracy was further evaluated against April, 2003 Emerge 1-ft. resolution aerial photography to estimate the validity of the predicted range of imperviousness for a second set of randomly selected pixels. This assessment proved disappointing, as only 7% of the pixels sampled predicted the correct impervious percentage range. The data set representing impervious surface acreage in 2005 has been archived in the GRANIT GIS clearinghouse, thereby making it available to the coastal resource community as well as the general public. The data are appropriate for watershed and subwatershed level characterizations. Users are discouraged from accessing these data to support larger scale mapping and applications

    Estimation of forest variables using airborne laser scanning

    Get PDF
    Airborne laser scanning can provide three-dimensional measurements of the forest canopy with high efficiency and precision. There are presently a large number of airborne laser scanning instruments in operation. The aims of the studies reported in this thesis were, to develop and validate methods for estimation of forest variables using laser data, and to investigate the influence of laser system parameters on the estimates. All studies were carried out in hemi-boreal forest at a test area in southwestern Sweden (lat. 58°30’N, long. 13°40’ E). Forest variables were estimated using regression models. On plot level, the Root Mean Square Error (RMSE) for mean tree height estimations ranged between 6% and 11% of the average value for different datasets and methods. The RMSE for stem volume estimations ranged between 19% and 26% of the average value for different datasets and methods. On stand level (area 0.64 ha), the RMSE was 3% and 11% of the average value for mean tree height and stem volume estimations, respectively. A simulation model was used to investigate the effect of different scanning angles on laser measurement of tree height and canopy closure. The effect of different scanning angles was different within different simulated forest types, e.g., different tree species. High resolution laser data were used for detection of individual trees. In total, 71% of the field measurements were detected representing 91% of the total stem volume. Height and crown diameter of the detected trees could be estimated with a RMSE of 0.63 m and 0.61 m, respectively. The magnitude of the height estimation errors was similar to what is usually achieved using field inventory. Using different laser footprint diameters (0.26 to 3.68 m) gave similar estimation accuracies. The tree species Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.) were discriminated at individual tree level with an accuracy of 95%. The results in this thesis show that airborne laser scanners are useful as forest inventory tools. Forest variables can be estimated on tree level, plot level and stand level with similar accuracies as traditional field inventories

    Developing Impervious Surface Estimates for Coastal New Hampshire

    Get PDF
    Future population growth and the corresponding increase in development in the coastal zone of NH are widely recognized as major threats to the integrity of coastal systems and their watersheds. The potential impacts associated with the expansion of developed land, and specifically with increasing amounts of impervious surfaces – rooftops, sidewalks, roads, and parking lots - may include significant changes in water quantity, degradation in water quality, and habitat loss. Because asphalt, concrete, stone, and other impenetrable materials effectively seal the ground surface, water is repelled and is prevented from infiltrating soils. Instead, stormwater runoff flows directly into our surface waters, depositing metals, excess nutrients, organics, and other pollutants into the receiving bodies. In addition to these environmental impacts, increasing levels of imperviousness can dramatically alter our landscapes, as forested and other natural settings are converted to urban/suburban uses. Many of the impacts associated with impervious surfaces had been well documented by studies in other areas of the country. However, comprehensive studies in coastal New Hampshire had not been undertaken. The primary goals of this project were to provide an accurate, current description of the extent of impervious surface coverage in this region, as well as an estimate of change in the amount of “imperviousness” over a recent, ten-year period

    NASA Earth Resources Survey Symposium. Volume 3: Summary reports

    Get PDF
    This document contains the proceedings and summaries of the earth resources survey symposium, sponsored by the NASA Headquarters Office of Applications and held in Houston, Texas, June 9 to 12, 1975. Topics include the use of remote sensing techniques in agriculture, in geology, for environmental monitoring, for land use planning, and for management of water resources and coastal zones. Details are provided about services available to various users. Significant applications, conclusions, and future needs are also discussed

    Third Earth Resources Technology Satellite Symposium. Volume 2: Summary of results

    Get PDF
    Summaries are provided of significant results taken from presentations at the symposium along with some typical examples of the applications of ERTS-1 data for solving resources management problems at the national, state, and local levels
    corecore