Multitemporal fraction images derived from Terra MODIS data for analysing land cover change over the Amazon region

摘要

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard Earth Observing System (EOS) Terra plataform has been designed to provide improved information for monitoring land, ocean, and atmosphere conditions. The design combined characteristics of the Advanced Very High Resolution Radiometer (AVHRR) and the Landsat Thematic Mapper (TM), adding spectral channels in the middle and thermal infrared wavelength and providing data in 250 m, 500 m and 1 km spatial resolutions. Spectral channels for atmospheric and cloud characterization have been included to permit both the removal of atmospheric effects on surface observations and the provision of atmospheric measurements (Justice et al. 1998). This work utilized the land product MOD13Q1, which is a vegetation index product with 250 m spatial resolution and is a composite of 16 days of observation over Mato Grosso State (figure 1). This product contains the composite of NDVI (Normalized Difference Vegetation Index), EVI (Enhanced Vegetation Index), red reflectance band (250m spatial resolution, 620-670 nm bandwidth), near infrared reflectance band (250 m spatial resolution, 841-876 nm bandwidth), blue reflectance band (500 m spatial resolution, rearranged to 250m, 459-79 nm bandwidth), medium infrared reflectance band (500m spatial resolution, rearranged to 250m, 2105-2155 nm bandwidth), quality assurance data for NDVI and EVI, view zenith angle, sun zenith angle, and relative azimuth angle average parameters (Lozar and Balbach 2002). The composites of NDVI and EVI were performed using the Constrained View Maximum Value Composite (CV-MVC) algorithm.