Variability of the relationships between heatwave and dust intrusions over France

The western region of Europe is frequently affected by the mineral dust intrusions from the nearby desert outbreaks. There are many investigations of dust events, especially over its southern part. However, in the contest of climate changing, a profound analysis of the evolution and dynamics of these episodes over the France region is of the great interest.

Satellite remote sensing techniques are utilized to investigate the whole region. The Moderate Resolution Imaging Spectroradiometer (MODIS) and the Multi-angle Imaging Spectroradiometer (MISR) data are used to obtain the optical and microphysical aerosol properties. Also, the numerical models such are Regional Climate Model (RegCM4-Chem) and Weather Research and Forecasting (WRF) have been used in this study. Moreover, the air quality model Prev'air is used to provide the air quality maps, especially over the main urban and industrial regions. Aerosol Robotic Network (AERONET) stations based on this region will provide data to validate the low spatial resolution results.

Beside of the aerosol events analysis, weather patterns, like temperature (surface and 850 hPa) Sea Level Pressure and 500 hPa Geopotential heights are derived from reanalysis during the periods of dust events.

More specifically, the main objectives of this study were:

Characterization of episodes of extreme dust aerosol load, using long-term observations.

Characterization of extreme temperature episodes, using meteorological data.

Establish links between dust and heat wave episodes, as well as their associated synoptic patterns.

The novelty of this work is the synergetic use of aerosol and meteorological data to establish the common mechanisms of two types of hazards which are detrimental to human’s health but have traditionally been studied separately: dust intrusions and heatwaves.  

The results show not regular trends on the dust intrusion frequency, duration, and intensity over the entire region. However, the combination of the meteorological and aerosol data over the different sectors of this region, give some insights over the features of these events. Furthermore, a heatwave catalogue with the extreme temperature events is associated with high aerosol loads in this region is created.