Aerosol physical, chemical and optical properties: laboratory measurements and remote sensing applications.

PhD student: Alexandre DEGUINE

Many atmospheric remote-sensing instruments allow detecting and measuring trace gas species from infrared Fourier Transform Spectrometer (FTS) embedded in balloon, aircraft and satellite platforms. Moreover, these high spectral resolution infrared observations also contain signatures due to atmospheric aerosols. Although it is possible to use these IR spectra to identify the chemical composition and the size distribution of the aerosol particles, the use of these measurements are up to now very sparse. This is explained by the complexity of the radiative transfer treatment in this case (absorption + scattering + thermal and solar emission...) and, the lack of optical properties obtained in the laboratory. This is why PC2A and LOA have developed an original methodology to derive complex refractive indices of particles from extinction spectra recorded in the infrared and UV- vis. spectral ranges, compatible with those of satellite instruments such as IASI or GOSAT, facilitating direct integration of laboratory measurements in the retrieval schemes. We propose to extend this project by broadening the nature of aerosols studied: liquid particles, mixed particles, solid particles coated with organic. Finally, it is intended to study the link between aging atmospheric particles and changes in their optical properties.

The candidate will have to justify a good knowledge in chemistry, physics or physical chemistry with. Spectroscopy, reactivity, and atmospheric optics would be a significant advantage.

Theme
Workpackage

Keywords
Aerosol metrology - Heterogeneous reactivity – Optical properties – Fourier transform Spectroscopy – Atmospheric sounding

Director: Hervé Herbin (LOA)
Co-director: Denis Petitprez (PC2A)

Laboratories: LOA et PC2A

Financing: Université Lille 1 / Labex CaPPA