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The suitability of the AISA airborne imaging spectrometer for monitoring lake water quality was tested in four surveys carried out in southern Finland in 1996-1998. Altogether, 11 lakes were surveyed and the total number of stations with concurrent remote sensing and limnological measurements was 127. The ranges of the water quality variables were: the sum(More)
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 of lakes and coastal waters in Finland. Also simulated LANDSAT TM data were tested. Satellite bands were simulated using airborne measurements with AISA imaging spectrometer. Semi-empirical algorithms with(More)
A semi-operative approach to retrieve chlorophyll-a concentration from airborne/spaceborne spectrometer observations has been developed and tested using the airborne imaging spectrometer (AISA) data from 11 lakes located in southern Finland. The retrieval approach is empirical and requires nearly simultaneous in situ training data on water quality for the(More)
A model was developed for estimating elastic and shrinkage properties of a softwood cell wall from the properties of its polymeric constituents: cellulose, hemicellulose and lignin. The theory of composite materials was used. Based on a literature survey, models of latewood, earlywood and compressionwood of a softwood cell wall structure were made. The(More)
Chlorophyll-a (chl-a) concentration of lake water can be measured with airborne (or spaceborne) optical remote sensing instruments. The rmse obtained here with empirical algorithms and 122 measurement points was 8.9 microg/l (all points used for training and testing). Airborne Imaging Spectrometer for Applications (AISA) was used in four lake water quality(More)
In a previous article of the authors a model was developed for estimating elastic and shrinkage properties of a softwood cell-wall. In the present article this model is enlarged to simulate the elastic properties of defect-free softwoods. The wood model consists of earlywood, latewood and ray cells, each of which have a different cell-wall structure. In the(More)
– Monitoring of environment requires several sources of information to be combined: "General knowledge" of the monitored area, measurement information on it and naturally previously made assessments of the same area. To use earth observation in monitoring of for example lake water quality, traditional images have limited value: How could they be used for(More)
– A user survey was conducted among Finnish professional users on their requirements on water quality information, which could be produced with remote sensing. The purpose of the survey was to direct the related research and development to the most interesting applications from the user perspective. The results additionally highlight the requirements for(More)
– Two field campaigns were used to demonstrate the usefulness of an atmospheric correction method specifically developed for Case 2 waters. The correction method utilizes bio-optical reflectance modeling and principal component analysis. The MODTRAN radiative transfer code simulations were conducted to obtain a statistical database for varying atmospheric(More)