CLASSIFICATION OF TYPES OF WEATHER AND THEIR INFLUENCE ON THE CONCENTRATIONS OF NITROGEN DIOXIDE, PARTICULATE MATERIAL (PM10) AND OZONE IN THE CITY OF MADRID (SPAIN)

The establishment of the weather types and associated air pollution are the two objectives that have been pursued in this research. The data used were the daily observations of meteorological surface and 850Hpa variables of the Madrid (Barajas) station and the daily pollution NO2, PM10 and O-3 of the stations of the air quality network of the city of Madrid. Factor analysis (ACP) was used to eliminate redundant information and the cluster analysis (Ward's method) to define weather types. It has been observed that the anticyclonic weather of winter, linked to masses of cold and dry air, is the one that produces high pollution concentrations of NO2 and PM10. In contrast, to the summer anticyclonic weather is associated with high pollution concentrations of ozone and if there are also invasions of Saharan air, there are also high immissions of PM10. Weather types with stronger winds, either anticyclonic or cyclonic, trigger lower immission levels of pollutants.