title: Direct gravimetric determination of aerosol mass concentration in central antarctica.
abstract: In Antarctica, experimental difficulties due to extreme conditions have meant that aerosol mass has rarely been measured directly by gravimetry, and only in coastal areas where concentrations were in the range of 1-7 μg m(-3). The present work reports on a careful differential weighing methodology carried out for the first time on the plateau of central Antarctica (Dome C, East Antarctica). To solve problems of accurate aerosol mass measurements, a climatic room was used for conditioning and weighing filters. Measurements were carried out in long stages of several hours of readings with automatic recording of temperature/humidity and mass. This experimental scheme allowed us to sample from all the measurements (up to 2000) carried out before and after exposure, those which were recorded under the most stable humidity conditions and, even more importantly, as close to each other as possible. The automatic reading of the mass allowed us in any case to obtain hundreds of measurements from which to calculate average values with uncertainties sufficiently low to meet the requirements of the differential weighing procedure (±0.2 mg in filter weighing, between ±7% and ±16% both in aerosol mass and concentration measurements). The results show that the average summer aerosol mass concentration (aerodynamic size ≤10 μm) in central Antarctica is about 0.1 μg m(-3), i.e., about 1/10 of that of coastal Antarctic areas. The concentration increases by about 4-5 times at a site very close to the station.
authors.affiliation: Department of Marine Science, Polytechnic University of Marche - Ancona, Via Brecce Bianche, 60131, Ancona, Italy. a.annibaldi@univpm.it
authors.forename: Anna
authors.initials: A
authors.lastname: Annibaldi
authors.forename: Cristina
authors.initials: C
authors.lastname: Truzzi
authors.forename: Silvia
authors.initials: S
authors.lastname: Illuminati
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Scarponi