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Jeffrey T. Morisette, Louis Giglio, Ivan Csiszar, Alberto Setzer, Wilfrid Schroeder, Douglas Morton, and Christopher O. Justice

(CEOS) global validation activities. These international entities have helped define the role of regional partners in validating global fire products (see information online at ). Integration with GOFC/GOLD and CEOS maximizes the applicability of this research beyond Brazil to the international effort to better understand global fire product accuracy. The primary goal of this paper is to evaluate the characteristics of two fire detection algorithms, both of which are

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Douglas C. Morton, Ruth S. DeFries, Yosio E. Shimabukuro, Liana O. Anderson, Fernando Del Bon Espírito-Santo, Matthew Hansen, and Mark Carroll

, facilitating more frequent analyses of deforestation. Quarterly or annual products, such as Vegetation Cover Conversion (VCC; MOD44A) and Vegetation Continuous Fields (VCF: MOD44B) products, provide periodic estimates of deforestation and forest cover, respectively. Fixed analysis periods for VCC and VCF global products provide routine estimates of deforestation, although infrequent product production may limit the ability to discern temporal information regarding forest clearing. In addition, algorithms

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Wilfrid Schroeder, Jeffrey T. Morisette, Ivan Csiszar, Louis Giglio, Douglas Morton, and Christopher O. Justice

aboard the National Oceanic and Atmospheric Administration (NOAA) polar-orbiting satellites is one of the most widely used instruments to monitor vegetation fires. While AVHRR was not specifically developed for fire detection ( Kidwell 1991 ), it has been widely used for this purpose because it is possible to obtain satisfactory results with this sensor (information online at , or ). A variety of fire detection algorithms

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Gregory P. Asner, David E. Knapp, Amanda N. Cooper, Mercedes M. C. Bustamante, and Lydia P. Olander

fractional cover analysis with Landsat ETM+ satellite data. 2. Methods 2.1. Per-pixel mixture analysis Our methodology is centered on an effort to break individual satellite pixels into constituent cover fractions of surface materials. To do so, we employ a general, probabilistic spectral mixture model for decomposing satellite spectral reflectance measurements into subpixel estimates of PV, NPV, and bare substrate covers ( Figure 1 ). This model is based on an algorithm developed for forest, savanna

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Ana M. B. Nunes and John O. Roads

measurements from satellites launched by the Defense Meteorological Satellite Program (DMSP) were used to provide daily rain-rate estimates for all experiments. The National Oceanic and Atmospheric Administration (NOAA)/National Environmental Satellite, Data, and Information Service (NESDIS) SSM/I algorithm ( Ferraro and Marks 1995 ), based on scattering and emission methods, was used to provide the rain-rate estimates. Scattering-based retrieval algorithms are usually used over land, and they do not

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Eraldo A. T. Matricardi, David L. Skole, Mark A. Cochrane, Jiaguo Qi, and Walter Chomentowski

interpretation and indirect estimation of the area of selective logging through in the Brazilian Amazon using Landsat imagery from 1992. Janeczek ( Janeczek 1999 ) tested a textural algorithm, individually using Landsat bands 3, 4, and 5 (red, near-infrared, and middle infrared, respectively) to detect patios. Patios were identified most effectively with band 5, because dry bare soil reflects more incoming radiation at those wavelengths than vegetation, resulting in good contrast on the images. The accuracy

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Cuizhen Wang, Jiaguo Qi, and Mark Cochrane

. Skole , C. A. Nobre , J. L. Hackler , K. T. Lawrence , and W. H. Chomentowski . 2000 . Annual fluxes of carbon from deforestation and regrowth in the Brazilian Amazon. Nature 403 : 301 – 304 . Huete , A. R. 1988 . A soil-adjusted vegetation index (SAVI). Remote Sens. Environ. 25 : 295 – 309 . Huete , A. R. , C. Justice , and W. Van Leeuwen . 1999 . MODIS vegetation index, MODIS algorithm theoretical basis document. NASA Goddard Space Flight Center, 120 pp

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Ellen Jasinski, Douglas Morton, Ruth DeFries, Yosio Shimabukuro, Liana Anderson, and Matthew Hansen

elevation, given a minimum mapping unit of 1.8 ha (significantly smaller than the 250-m grid cells used here). 2.2.3. Precipitation The Agência Nacional de Energia Elétrica (ANEEL) provided daily and monthly precipitation totals from 125 meteorological stations in Mato Grosso. These point data were plotted spatially, and monthly total values were interpolated using a four-step inverse distance-weighted algorithm. November was identified as a key month of crop sensitivity to precipitation for the wet

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Edson E. Sano, Laerte G. Ferreira, and Alfredo R. Huete

(INPE). For illustration purpose, Figure 3 shows the dry-season JERS-1 and TM color composite of the study area. The Landsat images were converted to the “top of atmosphere” apparent reflectances and then corrected for Rayleigh scattering and ozone absorption using the 6S radiative transfer code simulations ( Vermote et al. 1997 ). The corrected reflectance data were spectrally converted to the NDVI ( Rouse et al. 1974 ) and EVI ( Huete et al. 1994 ; Justice et al. 1998 ) algorithms as follows

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Carlos M. Souza Jr., Dar A. Roberts, and AndréL. Monteiro

25 control points extracted from the National Aeronautics and Space Administration (NASA) GeoCover 2000 Mosaic ( ). Next, the 1999 georectified Landsat image was used as the reference image to register the images acquired on the other dates ( Table 2 ). The registration was based on the triangulation algorithm and nearest-neighborhood resampling available in the Environment for Visualizing Images 4.0 software (ENVI; Research Systems, Boulder, Colorado), using at

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