MOD09Q1数据介绍.doc

Surface Reflectance 8-Day L3 Global 250m MOD09Q1 Short Name: MOD09Q1 A combination of Bands 2, 2, 1 displays a false-color Surface Reflectance image using 250-m data acquired between February 10–17, 2007 over parts of Chile and Argentina (h12v12). The fertile Central Valley of Chile appears to the southwest in red, as do the agricultural lowlands of Argentinas Las Pampas in the northeast corner of the image. The MODIS Surface Reflectance products provide an estimate of the surface spectral reflectance as it would be measured at ground level in the absence of atmospheric scattering or absorption. Low-level data are corrected for atmospheric gases and aerosols, yielding a level-2 basis for several higher-order gridded level-2 (L2G) and level-3 products. MOD09Q1 provides Bands 1 and 2 at 250-meter resolution in an 8-day gridded level-3 product in the Sinusoidal projection. Each MOD09Q1 pixel contains the best possible L2G observation during an 8-day period as selected on the basis of high observation coverage, low view angle, the absence of clouds or cloud shadow, and aerosol loading. Science Data Sets provided for this product include reflectance values for Bands 1 and 2, and a quality rating. Version-5 MODIS/Terra Surface Reflectance products are Validated Stage 2, meaning that accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts.? Change Points of Interest Reduced file volume: internal compression Improved aerosol retrieval Version 005 Overview See Product Description Layers Science Data Sets for MODIS Terra Surface Reflectance 8-Day L3 Global 250m SIN Grid V005 (MOD09Q1): Science Data Sets (HDF Layers) (3) UNITS BIT TYPE FILL VALID RANGE MULTIPLY BY SCALE FACTOR 250m Surface Reflectance Band 1 (620–670 nm) Reflectance 16-bit signed integer -28672 -100–16000 0.0001 250m Surface Reflectance Band 2 (841–876 nm) Reflectance 16-bit signed integer -28672 -100–16000 0.0001 250m Reflect