Articles | Volume 15, issue 11
Research article
12 Jun 2015
Research article |  | 12 Jun 2015

Aerosols over continental Portugal (1978–1993): their sources and an impact on the regional climate

A. L. Morozova and I. A. Mironova

Abstract. Understanding of aerosol sources that affect climate is an ongoing problem facing scientists as well as policymakers. The role of aerosols in local climate variability depends on a balance between light absorbing and scattering particles as well as on variability of environmental conditions. In this paper we investigate variability of aerosol content (both absorbing and scattering ultraviolet radiation) over continental Portugal in connection with aerosol sources (volcanic eruptions, dust events, wildfires and anthropogenic pollution). The effect of the aerosol on the climate is studied analyzing their contribution to variations of temperature, pressure, sunshine duration and precipitation over Portuguese regions. The present analysis is based on a developed modern multiple regression technique allowing us to build the statistical correlation models to determine both the main local aerosol sources and aerosol's influence on the climate of continental Portugal during 1978–1993. The analysis allows us to conclude that the main sources driving the variations of the aerosol content over studied locations are wildfires, mineral dust intrusions and anthropogenic pollution. The relations between the aerosol content variations and the atmospheric parameters depend on the level of urbanization of the studied region, the type of aerosol and the season. The most significant finding is the decrease of the daily maximum temperature (and diurnal temperature range) related to the decrease of sunshine duration observed during the summer periods of increased content of the absorbing aerosols in the atmosphere.

Short summary
The aerosols sources (volcanoes, mineral dust, wildfires, pollution) in continental Portugal were studied using ground and satellite measurements. The influence of the each source changes with the season and environment. Concerning the effect that aerosols have over the local climate variations change, the strongest influence was found for the less urbanized site and for the summer months. It consists in dependence of the maximum daily temperature variations on the absorbing aerosol content.
Final-revised paper