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Landsat 7 Scene Selection Strategy Based on Seasonal Greenness of Land Cover Type Landsat 7 ETM+ scene selection for MRLC 2000 can be improved based on information on land cover characteristics and vegetation phenology.
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Landsat 7 Scene Selection Strategy Based on Seasonal Greenness of Land Cover Type Landsat 7 ETM+ scene selection for MRLC 2000 can be improved based on information on land cover characteristics and vegetation phenology. Such information can be derived from the multi-temporal AVHRR data (e.g. Loveland and Belward, 1997, Reed et al., 1994).
Using temporal AVHRR NDVI greenness data to aid Landsat 7 scene selection for MRLC 2000. A scene selection strategy can be established for each mapping zone (or path/row). The methodology provides a consistent framework across the nation to populate the Landsat 7 imagery. The AVHRR data used in this study are from 1994-1998. The data have been smoothed to reduce cloud effect (Reed, 1994). Land cover data used to stratify within each mapping zone are from the National Land Cover Data (NLCD) developed from the MRLC 1990 project.
Selection criteria: 1. Capture major vegetation phenology (leaf-on and leaf-off, peak greenness) 2. Maximize separation among dominant land cover types. 3. Select up to 3 scenes over a growing season for each mapping zone. First scene: July-August (15-16th biweek period), near peak greenness and distinct difference in greenness among most land cover types. Second Scene: April (8-9th biweek period), leaf-off before peak greenness (except small grains) large greenness difference between small grains and other land cover types. Third scene: Sept.-Oct. (20-21th biweek period), leaf-off after peak greenness.