Effect of south winds on daily mortality in Athens

Abstract

The present study investigated the possible effects of south winds on daily mortality in Athens during the period 1983-1991. The mortality data were assembled from the Athens city registry and registries of the adjacent municipalities. The mean daily dry bulb and dew point temperature, as well as the wind speed and duration for which the south winds were blowing, were recorded by the Institute of Meteorology and Physics of the Atmospheric Environment of the National Observatory of Athens. Temperature, dew point temperature, seasonal and long-term patterns, as well as other potential confounders, have been adjusted for. Synoptic circulation patterns over Athens have been taken into account. Regression modelling was used for the analysis adjusting for autocorrelation where appropriate. When the south winds were added to the basic model (adjusting for year, season, day of the week, temperature, dew point temperature and black smoke), an increase of 3.2 % in the daily mortality (95% CI: 1.4 to 4.8%) was observed on the days when south winds were blowing, compared to the days without a south wind. When a variable for southwesterly synoptic flow was also included in the model, the effect of south winds remained approximately the same: a 2.9% increase in daily mortality (95% CI: 1.9 to 4.7%), whilst the effect of the southwesterly synoptic flow was also significant and of similar magnitude (a 3.4% increase in the daily number of deaths, 95% CI: 1.1 to 5.8%). Longer duration and higher wind speed were also associated with increased mortality. In conclusion, adjusting for all known confounders, it was found that the days on which south winds blow are characterized by increased mortality in Athens. © Inter-Research 2009.