Aerosols, these tiny particles of the lower
atmosphere, are one important component of atmosphere affecting climate
(radiative effects, water cycle) and air quality.
For characterizing and monitoring aerosols,
water wapor and clouds, LOA and Cimel, in collaboration with NASA’s GSFC,
developed the robotic solar photometer for the AERONET network in the early
1990s. The meeting between CNRS and NASA researchers and the industrial company
Cimel led to the definition of an automatic, robust, autonomous solar
photometer that transmits its data by radio, providing AOD and particle size in
real time. In 1998, the French component (PHOTONS) was awarded the INSU
Observation Service label.
Cimel is NASA – AERONET’s exclusive supplier of automatic Sun Sky Lunar photometers (CIMEL CE318-T) operating in near real time and providing aerosol optical and columnar microphysical properties.
The plume of the Icelandic volcano Bardarbunga pollutes the air in the Nord – Pas de Calais
At the end of September 2014, the Nord – Pas de Calais region suffered an episode of heavy air pollution due to the eruption of the Icelandic volcano Bardarbunga, which has already been going on for more than a month.
The analysis of observations of the volcanic plume, obtained from the ground, thanks to CIMEL photometers and LiDAR, and by satellite, by a team of researchers, engineers and technicians from the Laboratoire d’optique atmosphérique (LOA, CNRS / Université Lille 1) in collaboration with the association for monitoring air quality atmo Nord – Pas de Calais, allowed them to describe the journey, from Iceland, of the volcanic plume and its arrival in the lowest layers of the French atmosphere.
Aerosol particles are important and highly variable components of the terrestrial atmosphere, and they affect both air quality and climate. In order to evaluate their multiple impacts, the most important requirement is to precisely measure their characteristics.
Remote sensing technologies such as lidar (light detection and ranging) and sun/sky photometers are powerful tools for determining aerosol optical and microphysical properties. In our work, we applied several methods to joint or separate lidar and sun/sky-photometer data to retrieve aerosol properties. The Raman technique and inversion with regularization use only lidar data. The LIRIC (LIdar-Radiometer Inversion Code) and recently developed GARRLiC (Generalized Aerosol Retrieval from Radiometer and Lidar Combined data) inversion methods use joint lidar and sun/sky-photometer data.
Mobile Automatic Aerosol Monitoring Solution project (M-AAMS)
The team of scientists left Lille on Monday morning, direction the « Observatoire de Haute Provence » located in Aix-en-Provence.
Along its trip, the car takes continuous measurements of the atmosphere.
Scientists on board follow them and make sure that all the instruments work properly. The car is not only equipped with a wide range of instruments, but also with a camera and an internet connexion: all needed to document the trip of the car in real time!
Follow the adventure of the #CaPPA_Mobile on twitter.
If the system has already been used locally, this time the route extends from Lille to Aix-en-Provence, nearly 1000 km. This experience is part of Ioana Popovici’s thesis work: “Measurement of aerosol variability at high spatial and temporal resolution, in connection with air quality, using an innovative mobile system. »
This time, the vehicle is equipped with a Cimel CE370 LiDAR(532 nm), the mobile PLASMA photometer (340-1600 nm), a granulometer (GRIMM) and a weather station.
The data collected by the mobile system is being analysed and validated. An inter-comparison of the data will be made with the data collected by the fixed measurement stations of the Haute Provence Observatory and the ATMO stations located along the route. Access to online data of the instrumented car.
The science team relied on good weather to collect as much data as possible. Although the sky cleared several times, clear, cloudless sky conditions were not frequently encountered. Under these circumstances it is difficult to carry out solar photometry measurements and to obtain additional information by combining LIDAR with a solar photometer. However, LIDAR has observed the vertical and spatial variability of the atmosphere. The observation was limited to about 2-3 km altitude by the presence of clouds over most of the trip.
A camera fixed on the roof of the car “confirms” the LIDAR measurements, as follows:
Spatio-temporal series LIDAR obtained between Lille and Valence on 28/03/2016
