An automatic collector to monitor insoluble atmospheric deposition: application for mineral dust deposition
- 1Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR7583 CNRS, Université Paris Diderot, Université Paris-Est Créteil, Institut Pierre-Simon Laplace, France
- 2Ingénierie, Conseil, Assistance technique, Recherche, Etude (ICARE Ingénierie), Paris, France
- 3Mediterranean Institute of Oceanography (MIO), UMR7294 CNRS, UMR235 IRD, Université Aix-Marseille, Université du Sud Toulon-Var, France
- apresent address: Institut de Physique du Globe de Paris (IPGP), UMR7154 CNRS, Sorbonne Paris Cité, Université Paris Diderot, France
Abstract. Deposition is one of the key terms of the mineral dust cycle. However, dust deposition remains poorly constrained in transport models simulating the atmospheric dust cycle. This is mainly due to the limited number of relevant deposition measurements. This paper aims to present an automatic collector (CARAGA), specially developed to sample the total (dry and wet) atmospheric deposition of insoluble dust in remote areas. The autonomy of the CARAGA can range from 25 days to almost 1 year depending on the programmed sampling frequency (from 1 day to 2 weeks respectively). This collector is used to sample atmospheric deposition of Saharan dust on the Frioul islands in the Gulf of Lions in the Western Mediterranean. To quantify the mineral dust mass in deposition samples, a weighing and ignition protocol is applied. Almost 2 years of continuous deposition measurements performed on a weekly sampling basis on Frioul Island are presented and discussed with air mass trajectories and satellite observations of dust. Insoluble mineral deposition measured on Frioul Island was 2.45 g m−2 for February to December 2011 and 3.16 g m−2 for January to October 2012. Nine major mineral deposition events, measured during periods with significant MODIS aerosol optical depths, were associated with air masses coming from the southern Mediterranean Basin and North Africa.