1 - Remote Sensing
2 - Page 2
3 - Page 3
4 - Page 4
5 - Page 5
The Monsoon'90 multidisciplinary field campaign was conducted at the USDA ARS Walnut Gulch Experimental Watershed (WGEW) in SE Arizona during June-September 1990. The objective of this combined ground, aircraft and satellite campaign was to assess the feasibility of utilizing remotely-sensed data coupled with water and energy balance modeling for large area estimates of fluxes in semiarid rangelands.
Scientists measuring surface spectral reflectance of the WGEW grassland using yoke-mounted multi-band radiometers.
Moran, M.S., W.P. Kustas, A. Vidal, D.I. Stannard, J.H. Blanford and W.D. Nichols, Use of ground-based remotely sensed data for surface energy balance evaluation of a semiarid rangeland, Water Resource Res. 30:1339-1349. 1994.
Moran, M.S., T.R. Clarke, W.P. Kustas, M. Weltz, S.A. Amer and A.R. Huete, Evaluation of hydrologic parameters in semiarid rangeland using remotely sensed spectral data, Water Resource Res. 30:1287-1297. 1994.
|back to top|
The Walnut Gulch '92 field campaign was conducted during the dry, early-monsoon, mid-monsoon, post-monsoon and "drying" seasons from April through November 1992 at WGEW. The overall research goal was to investigate the seasonal hydrologic dynamics of the region and to define the information potential of combined optical-microwave remote sensing.
Images of surface temperature and reflectance (color composite) measured by the Landsat5 TM sensor on 17 June 1997 (left) and images of vegetation biomes (upper right) and surface elevation (lower right; from 800 to 3000 km) for the Upper San Pedro Basin at 100 m spatial resolutions.
Moran, M.S., A.F. Rahman, J.C. Washburne, D.C. Goodrich, M.A. Weltz and W.P. Kustas, Combining the Penman-Monteith equation with measurements of surface temperature and reflectance to map regional evaporation rates, Agric. For. Meteorol.80:87-109. 1996.
|back to top|
Semi-arid lands are especially vulnerable to the impacts of natural and human induced environmental stresses. The Semi-Aridland-Surface-Atmosphere (SALSA) program is an ARS-led,multi-agency research program that seeks to understand, model, and predict the consequences of widespread environmental (global) change on the water balance and ecological complexity of semi-arid river basins over a range of time scales. Combining both ground-based and remote sensing technologies, SALSA scientists from several countries are intensively studying the Upper San Pedro Basin of southeastern Arizona and northeastern Sonora, Mexico. The results of this effort will not only help the local community better manage resources in their basin but will also provide the scientific and technological understanding needed to resolve similar problems in other semi-arid regions of the USA and the world.
Goodrich, D.C., A. Chehbouni, B. Goff, B. MacNish, T. Maddock, S. Moran, et al., An overview of the 1997 activities of the semi-arid land-surface-atmosphere (SALSA) program, Amer. Meteorol. Soc., Spec. Symp. On Hydrology, 11-16 January, Phoenix, AZ, p. 1-7. 1998.
Maddock, T. III, R.D. MacNish, D.C. Goodrich, D.G. Williams, W.J. Shuttleworth, B.A. Goff, R.L. Scott, M.S. Moran, D.I. Cooper, L.E. Hipps and A.G. Chehbouni, The overview of atmospheric and surface water couplingto regional groundwater models in semi-arid basins, Amer. Meteorol. Soc., Spec. Symp. On Hydrology, 11-16 January, Phoenix, AZ, p. 38-42. 1998.
Moran, S., D. Williams, D. Goodrich, A. Chehbouni, et al., Overview of remote sensing of semi-arid ecosystem function in the Upper San Pedro River basin, Arizona, Amer. Meteorol. Soc., Spec. Symp. On Hydrology, 11-16 January, Phoenix, AZ, p. 49-54. 1998.
|back to top|
A NASA-funded project has been underway for three years to develop operational techniques for the use of Landsat TM and ETM+ data for agricultural and natural resource management. The approach will include (1) supplementing Landsat TM data with synthetic aperture radar (SAR) data from other currently operating and proposed sensors to compensate for the infrequent coverage provided by Landsat, and (2) using the TM-derived determinations of surface plant and soil conditions to update modeled plant growth and evaporation based on physical models and meteorological data. The project is in the third stage of a three-stage schedule, where the first year's work was based solely on existing data sets. The products were algorithms to allow "interchangeable" usage of SAR data with TM data for vegetation status and moisture condition determination, and a plant growth model designed to assimilate infrequent inputs of plant parameters from remotely sensed data. In years 2-3, Landsat TM and ERS-2 SAR images were acquired at two sites in Arizona to validate these techniques at the regional scale for heterogeneous landscapes. Current work is focused on using the combined remote sensing/modeling approach for investigations of the daily to interannual changes of rangeland vegetation in the semiarid Southwest, and for aiding such farm management decisions as scheduling applications of fertilizer and irrigation water. This project has been conducted as part of the NASA Landsat-7 Science Team which provides expertise and information on such activities as instrument pre-development, science planning, instrument calibration, field validation, and algorithm development.
Nouvellon, Y.P., M.S. Moran, R.B. Bryant, W. Ni, P. Heilman, B. Emmerich, D. LoSeen, A. B?gu?, S. Rambal and J. Qi, Combining a SVAT model with Landsat imagery for a ten-year simulation of grassland carbon and water budget, 2nd Intl. Conf. Geospatial Information in Agric.and For. 10-12 Jan., Orlando, Fla. I-257-I-264. 2000.
Moran, M.S., Y. Nouvellon, R.B. Bryant and W. Ni, Assimilating Landsat imagery in a grassland growth model: a case study in Arizona, 14th William T. Pecora Memorial Remote Sensing Symp. 6-10 Dec., Denver, CO. 1999.
|back to top|
One half of all U.S. land and 60% of the landmass of the world is classified as rangeland and many of these rangelands have suffered severe degradation over the years. Ecological degradation and an increase in bare soil negatively impact livestock production, erosion control, biodiversity, and CO2 sequestration. To effectively manage these rangelands, managers need spatially and temporally distributed information on vegetation cover, biomass production, and green-up time. The RANGES program proposes to use NASA's EOS (Earth Observation System) products to provide critical information to end-users on an operational basis for livestock management, fire-fuel estimation, wildlife habitat analysis and rangeland health assessment. RANGES offers a) an operational procedure to transform EOS data into information products and b) a protocol that involves range managers, remote sensing scientists, and commercial firms to apply, and then to assess the value-added EOS products for management applications. Scientists will work hand in hand with range managers and ranchers to define, develop, evaluate, and prototype EOS-derived products. At the end of the project, an assessment of the EOS-derived products for rangeland management will be made by our end-users to determine their willingness to pay for the ongoing provision of EOS-derived products.
Qi, J., R. Marsett, P. Heilman, 2000, Rangeland vegetation cover estimation from remotely sensed data, 2nd International conference on Geospatial Information in Agriculture and Forestry, Lake Buena Vista, Florida, 10-12 January, 2000. II-243-252.
|back to top|
ARS scientists at SWRC secured a grant from the National Aeronautics and Space Administration (NASA) to participate in validation of the Earth Observation-1 (EO-1) mission. The EO-1 satellite is scheduled for launch in August 2000 with a primary objective of evaluating selected technologies for maintaining the 27-year continuity of the Landsat data stream. The primary objective of the SWRC study is to determine the suitability of the EO-1 image quality and data products to meet the needs of Landsat-class observations, termed Landsat data continuity. One study site will be the USDA ARS Walnut Gulch Experimental Watershed (WGEW) near Tucson, Arizona. Using on-site measurements of atmospheric conditions and measurements of surface reflectance of large, uniform targets, it will be possible to determine the accuracy of image reflectance factor retrieval. For the same images, on-site measurements of soil and plant characteristics will be used to determine the accuracy of image-derived data products suitable for agricultural and rangeland applications.
The EO-1 Satellite at NASA Goddard Space Flight Center in the Clean Tent
|<< Previous 1 2 3  5 Next >>|