Distribution of PM10 in Urban Athens as Obtained with the use of MERIS - Assessment of Potential Health Impact
Cartalis, Constantinos; Asimakopoulos, Dimosthenes; Karvounis, Giorgos
University of Athens, GREECE

In this study ground based measurements of PM10 for the urban agglomeration of Athens are correlated to satellite measurements of irradiance as provided by the Medium Resolution Imaging Spectrometer (MERIS). For this to be accomplished five different methods are used: a) Direct correlation of ground measurements of PM10 to satellite measurements of irradiance b) Correlation of normalised satellite measurements of irradiance to ground measurements of PM10 c) Neural network (Perceptron) and Principal Component Analysis d) Correlation of the images' contrast to ground measurements and e) as in d) with the use of reference image. All five methodologies are applied to orthocorrected images (with the use of VISAT and of the model GETASSE30), whereas the resampling of pixels was made on the basis of nearest neighbor interpolation. Furthermore all used methods are assessed to provide a number of interesting conclusions: a) A correlation is observed between irradiance and the concentrations of PM10 from the ground network b) The correlation varies in terms of its significance as a function of the concentration of PM10 c) In the case that concentrations of PM10 are low, a dispersion in the values of radiance is observed d) the neural network fails to simulate in a satisfactory manner the concentrations of PM10. On the basis of the defined correlation, the spatial distribution of PM10 in the urban agglomeration of Athens is developed with the use of the irradiance values from MERIS. Results are provided by Municipality in the urban agglomeration of Athens and are also related to recents studies on the impact of excessive concentrations of PM10 to human health. Finally, a through discussion on the capacity of satellite remote sensing to support urban air quality studies (in terms of PM10) is provided.