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Forest cover is of great interest to a variety of scientific and land management applications, many of which require not only information on forest categories, but also tree canopy density. In previous studies, large area tree canopy density had been estimated at spatial resolutions of 1km or coarser using coarse...

The Landsat 7 spacecraft and its Enhanced Thematic Mapper Plus (ETM+) were launched on April 15, 1999. Pre-launch modeling of the ETM+ optical system predicted that modulation transfer function (MTF) performance would change on-orbit. A method was developed to monitor the along-scan MTF performance of the ETM+ sensor system using...

The Thematic Mapper (TM) instruments onboard Landsats 4 and 5 provide high-quality imagery appropriate for many different applications, including land cover mapping, landscape ecology, and change detection. Precise calibration was considered to be critical to the success of the Landsat 7 mission and, thus, issues of calibration were given high...

During the spring and summer of 1996, 1997, and 1998, measurements of phytoplankton- chlorophyll concentration, Secchi disk transparency, and color were made at 97 Massachusetts lakes within 24 hours of Landsat Thematic Mapper imaging of the lakes in an effort to assess water quality and trophic state. Spatial distributions of...

No abstract available....

One objective of the MultiResolution Land Characteristics (MRLC) consortium is to map general land-cover categories for the conterminous United States using Landsat Thematic Mapper (TM) data. Land-cover mapping and classification accuracy assessment are complete for the eastern United States. The accuracy assessment was based on photo-interpreted reference data obtained from...

No abstract available....

The Landsat Earth observation approach introduced in 1972 created a new way of monitoring land cover and land use globally. The Landsat 7 mission, successfully launched on April 15, 1999, continues those observations and demonstrates significant progress in precise numerical radiometry, spectral differentiation, and seasonally repetitive monitoring. Substantial improvements in...

Landsat, with its wide swath and high resolution, fills an important mesoscale gap between atmospheric variations seen on a few kilometer scale by local surface instrumentation and the global view of coarser resolution satellites such as MODIS. In this important scale range, Landsat reveals radiative effects on the few hundred-meter...

Historically, it appears that some of the WRCF have survived because i) they lack sufficient quantity of commercially valuable species; ii) they are located in remote or inaccessible areas; or iii) they have been protected as national parks and sanctuaries. Forests will be protected when people who are deciding the...

Landsat Thematic Mapper images from 1990 to 1996 and collateral data sources were used to classify the land cover of the Mermentau River Basin (MRB) within the Chenier Plain of coastal Louisiana. Landcover classes followed the definition of the National Oceanic and Atmospheric Administration's Coastal Change Analysis Program; however, classification...

An empirical model was used to relate forest type and hurricane-impact distribution with wind speed and duration to explain the variation of hurricane damage among forest types along the Atchafalaya River basin of coastal Louisiana. Forest-type distribution was derived from Landsat Thematic Mapper image data, hurricane-impact distribution from a suite...

We demonstrate new multi-phase, multi-scale approaches for sampling and modeling native and exotic plant species to predict the spread of invasive species and aid in control efforts. Our test site is a 54,000-ha portion of Rocky Mountain National Park, Colorado, USA. This work is based on previous research wherein we...

Vegetation on the Seward Peninsula, Alaska, which is characterized by transitions from tundra to boreal forest, may be sensitive to the influences of climate change on disturbance and species composition. To determine the ability to detect decadal-scale structural changes in vegetation. Change Vector Analysis (CVA) techniques were evaluated for Landsat...

The enhanced thematic mapper (plus) (ETM+) instrument on Landsat 7 shares the same basic design as the TM sensors on Landsats 4 and 5, with some significant improvements. In common are six multispectral bands with a 30-m ground-projected instantaneous field of view (GIFOV). However, the thermaL-IR (TIR) band now has...

The U.S. Geological Survey, in cooperation with other government and private organizations, is producing a conterminous U.S. land-cover map using Landsat Thematic Mapper 30-meter data for the Federal regions designated by the U.S. Environmental Protection Agency. Accuracy assessment is to be conducted for each Federal region to estimate overall and...

The North American Breeding Bird Survey (BBS) has received criticism that the bird habitat sampled along the 24.5 mile long roadside transects may not be proportional to regional totals. If true, trends in bird populations recorded by the BBS may not be sensitive predictors of regional or continental change...

The study is summarized in the Adobe Acrobat Portable Document Format (PDF) file OF00-309.PDF. This publication also contain satellite full-scene images of selected areas along the U.S.-Mexico border. These images are presented as high-resolution images in jpeg format (IMAGES). The folder LOCATIONS in contains TIFF images showing exact positions of...

PART A: Ground-water evapotranspiration data from five sites in Nevada and seven sites in Owens Valley, California, were used to develop equations for estimating ground-water evapotranspiration as a function of phreatophyte plant cover or as a function of the depth to ground water. Equations are given for estimating mean daily...

The U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency, has produced a land cover dataset for the conterminous United States on the basis of 1992 Landsat thematic mapper imagery and supplemental data. The National Land Cover Dataset (NLCD) is a component of the USGS Land Cover...

Dynamic surficial changes and changes in the position of the firn line and the areal extent of Hofsjökull ice cap, Iceland, were studied through analysis of a time series (1973–98) of synthetic-aperture radar (SAR) and Landsat data. A digital elevation model of Hofsjökull, which was constructed using SAR interferometry, was...

The Landsat 7 Image Assessment System was developed to characterize and calibrate the radiometric and geometric performance of the Landsat 7 Enhanced Thematic Mapper Pius (ETM+) instrument. Algorithms and software assess the geometric performance of the Landsat 7 spacecraft and ETM+ sensor system and perform geometric calibration by estimating sensor...

There was a one-time opportunity to obtain nearly coincident coverage from both Landsat 5 and Landsat 7 as Landsat 7 drifted to its final orbital position during the initialization and verification phase following launch. During the underfly period, Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data were collected using the...

Staff at the U.S. Geological Survey (USGS) EROS Data Center (EDC) process Landsat 7 data for customer distribution on two distinct systems. The Distributed Active Archive Center (DAAC) processing is done on the Level -1 Product Generation System (LPGS), and the USGS processing is completed on the National Land Archive...

The U.S. Geological Survey's (USGS) Earth Explorer Web site provides access to millions of land-related products, including the following: Satellite images from Landsat, advanced very high resolution radiometer (AVHRR), and Corona data sets. Aerial photographs from the National Aerial Photography Program, NASA, and USGS data sets.  Digital cartographic data from...