Atmospheric correction of a seasonal time series of Hyperion EO-1 images and red edge inflection point calculation

Abstract

This study covers the preprocessing and atmospheric correction of a seasonal time series five Hyperion EO-1 images from Hyytiala, Southern Finland (61° 51'N, 24° 17'E). The time series ranges from May 5 th 2010 to July 11 th 2010, covering much of the growing season and the seasonal changes in vegetation reflectance. Atmospheric correction of the time series was done with Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) and ATmospheric CORrection (ATCOR) algorithms for comparison. Both algorithms performed well with Hyperion imagery. Different red edge inflection point (REIP) calculation methods were analyzed to determine their applicability for Hyperion imagery. REIP was calculated using four-point interpolation, Lagrangian interpolation, and fifth order polynomial fitting. Due to the dynamics of the red edge, polynomial fitting was seen as the best method for calculating the REIP. REIP did not correlate strongly with Leaf Area Index (LAI) but a stronger correlation was observed with understory REIP.