Résumé en anglais
The pattern of marble discoloration at the Taj Mahal, Agra, India, appears to be most prevalent in areas that are both shaded from early morning sun and protected from rainfall. An explanation, based on atmospheric modelling concepts, will be presented that attributes, at least in part, the discoloration to the silultaneous occurence of high concentrations of pollutants and condensation on the marble surfaces in the early morning