Detection of water quality using simulated satellite data and semi-empirical algorithms in Finland

The aim of the study was to test the feasibility of the band combination of the TERRA MODIS and ENVISAT MERIS instruments for operational monitoring o f lakes and coastal waters in Finland. Also simulated LANDSAT TM data were tested. Satellite bands were simulated using airborne measurements with AIS A imaging spectrometer. Semi-empirical algorithms with simulated satellite data were tested against field observations using regression analysis. Inte rpretation of chlorophyll a, suspended matter, turbidity and secchi-disk de pth was included in the analyses. The data for this study were gathered in campaigns carried out in May and August 1997 and August 1998 both for lakes in southern Finland and coastal waters of the Baltic Sea. The data set inc luded 85 in situ observations for lakes and 107 for coastal waters. Our res ults show that the band combination to be included in the ENVISAT MERIS ins trument enables the interpretation of watts quality. including chlorophyll a concentration using semiempirical algorithms both for lakes and coastal w aters. MERIS band 9 centred at 705 nm is proven to be of vital importance f or the detection of chlorophyll a in local surface waters. (C) 2001 Elsevie r Science B,V. All rights reserved.