Heatwaves and Their Impact on Air Quality in Greater Cairo, Egypt

Abstract

Several heatwaves (HWs) have been recorded in Egypt in recent years. Some of these HWs were mild, while others were severe and resulted in mortalities and morbidities. On the other hand, air pollution is considered a health issue in Egypt’s megacities, especially the capital city, Cairo, and its surroundings, the Greater Cairo (GC) region. In this study, we examine a number of HWs that have hit Egypt in recent years, along with the state of air quality, in terms of PM10, NO2, and O3, during the period of HW incidence, with a focus on the GC region. During the period of study, the frequency, intensity, and duration of HWs have been observed to increase. The total number of recorded HW events was 190, encompassing 376 HW days. The time series of daily mean NO2 showed no correlation with temperature during the months that experienced HWs cases. Conversely, PM10 and O3 concentrations exhibited a similar pattern as that of the daily maximum temperature. This increase in the two pollutant concentrations led to a degradation of the air quality, as demonstrated by the fact that the Air Quality Health Index went from “moderate risk”, on normal days, to “high risk” during the HWs.

Keywords

• extreme weather events
• air pollution
• particulate matter
• nitrogen dioxide
• ozone
• air quality health index