QUANTITATIVE MONITORING OF WATER PROPERTIES WITH THE AIRBORNE IMAGING SPECTROMETER AISA

Abstract

. Remote sensing measurements with an airborne imaging spectrometer (AISA) were carried out on Finnish lakes and the Archipelago Sea to test the suitability of passive optical remote sensing methods for quantitative monitoring of different water properties. Eight water characteristics were under investigation: concentrations of chlorophyll a, pheophytin, suspended matter (Nuclepore and Whatman GFC filters), total phosphorus, total and dissolved organic carbon; water turbidity; and the Secchi disk depth. Over 70 retrieval variables from simple spectral ratios and their combinations to more sophisticated functions were tested. The suitability of two different spatial resolutions (20 x 20 and 100 x 100 m) was tested. Algorithms were found for quantitative estimation ofthe above-mentioned water characteristics from spectral data measured with AISA.