Estimating the effective spatial resolution of an AVHRR time series

D. J. Meyer

doi:10.1080/01431169608949122

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Estimating the effective spatial resolution of an AVHRR time series

D. J. Meyer

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Abstract

A method is proposed to estimate the spatial degradation of geometrically rectified AVHRR data resulting from misregistration and off-nadir viewing, and to infer the cumulative effect of these degradations over time. Misregistrations are measured using high resolution imagery as a geometric reference, and pixel sizes are computed directly from satellite zenith angles. The influence or neighbouring features on a nominal 1 km by 1 km pixel over a given site is estimated from the above information, and expressed as a spatial distribution whose spatial frequency response is used to define an effective field-of-view (EFOV) for a time series. In a demonstration of the technique applied to images from the Conterminous U.S. AVHRR data set, an EFOV of 3·1km in the east-west dimension and 19 km in the north-south dimension was estimated for a time series accumulated over a grasslands test site.

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D. J. Meyer. 2007-04-27. Estimating the effective spatial resolution of an AVHRR time series. https://doi.org/10.1080/01431169608949122

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