Correlation of turbidity with Indian Remote Sensing Satellite - 1 A data

Remote sensing applications in hydrology are becoming more and more widespread. Choubey (1992) describes an interesting application in surface water hydrology: the correlation of turbidity in the surface water of a reservoir with remote sensing data. Choubey's paper discusses the first application of this type with the Indian Remote Sensing Satellite-1A (IRS-1A). The multispectral digital data cover the Tawa reservoir region. Water samples were collected concurrent with the satellite overpass. Good correlation is found between the turbidity and suspended solids on the one hand, and the satellite recorded pixel values on the other hand. Choubey follows the same procedure as Khorram & Cheshire (1985). This procedure is certainly sufficient for a feasibility study, and this is the important merit of Choubey's paper, but it does not lead to reproducible results that can be applied to other satellite images. In this discussion, additional image processing techniques and the consequences for Choubey's results are investigated. The techniques are performed on the mean pixel values as they appear in the original paper.