|Using NIR and SWIR wavelengths for turbid water corrections: the SIMEC environment correction and in-situ evidence of non-zero reflectance [Presentation]|
Knaeps, E.; Sterckx, S.; Raymaekers, D.; Ruddick, K.; Dogliotti, A.I. (2012). Using NIR and SWIR wavelengths for turbid water corrections: the SIMEC environment correction and in-situ evidence of non-zero reflectance [Presentation]. VITO/MUMM: Mol, Brussel. 4 pp.
|Auteurs|| || Top |
- Knaeps, E.
- Sterckx, S.
- Raymaekers, D.
- Ruddick, K.
- Dogliotti, A.I.
In this presentation both the NIR and SWIR spectral regions are investigated to improve the current correction schemes for turbid waters. The NIR is used in a new environment correction for MERIS based on the correspondence with the NIR similarity spectrum. The new correction is referred to as SIMEC, SIMilarity Environment Correction. The NIR similarity spectrum provides a base to both detect and correct adjacency effects. Detection of the magnitude of the environment effects is based on the deviations from the NIR similarity spectrum. The adjacency correction algorithm estimates the contribution of the background radiance based on the correspondence with the NIR similarity spectrum.The water-leaving reflectance in the SWIR is generally assumed to be zero (“black pixel assumption”), even for highly turbid waters. In this presentation some evidence is presented of non-zero water-leaving reflectance between 1000 and 1150 nm. The first results are shown of a measurement campaign at the Scheldt river in Belgium The measurements give evidence that the SWIR black pixel assumption is not valid here between 1000 and 1150 nm and that backscattering by suspended particles influence the retrieved signal.