Seasonal Evolution of Size-Segregated Particulate Mercury in the Atmospheric Aerosol Over Terra Nova Bay, Antarctica

• Published in: Molecules
• Main Authors: Illuminati, Silvia, Annibaldi, Anna, Bau, Sébastien, Scarchilli, Claudio, Ciardini, Virginia, Grigioni, Paolo, Girolametti, Federico, Vagnoni, Flavio, Scarponi, Giuseppe, Truzzi, Cristina
• Other Authors: Università Politecnica delle Marche Ancona (UNIVPM), Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Agenzia Nazionale per le nuove Tecnologie, l’energia e lo sviluppo economico sostenibile = Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: particulate mercury; mercury size-resolved distribution; dry deposition; meteorological parameter; backward trajectories; Antarctica; [CHIM]Chemical Sciences; [CHIM.GENI]Chemical Sciences/Chemical engineering; Antarctic; Terra Nova Bay; The Antarctic; Antarc*; Antarctique*; Sea ice
• Online Access: https://hal.science/hal-03063790; https://hal.science/hal-03063790/document; https://hal.science/hal-03063790/file/publi_molecules_SI_Hg%20Antarctica.pdf; https://doi.org/10.3390/molecules25173971

International audience Size-fractionated particulate mercury (PHg) measurements were performed from November 2017 to January 2018 at Terra Nova Bay (Antarctica) for the first time. Samples were collected every 10 days by a six-stage high-volume cascade impactor with size classes between 10 µm and 0.49 µm. Total PHg concentrations were maxima (87 ± 8 pg m −3) in November, then decreased to values~40% lower and remained almost constant until the end of the sampling period (~30 pg m −3). The trimodal aerosol mass distribution reveals that from 30% to 90% of the total PHg came in the size > 1.0 µm. Hg in the two coarse fractions was probably produced by the adsorption of oxidized Hg species transported by air masses from the Antarctic plateau or produced locally by sea ice edges. PHg in accumulation mode seemed to be related to gas-particle partitioning with sea salt aerosol. Finally, average dry deposition fluxes of PHg were calculated to be 0.36 ± 0.21 ng m −2 d −1 in the accumulation mode, 47 ± 44 ng m −2 d −1 in the first coarse mode, and 37 ± 31 ng m −2 d −1 in the second coarse mode. The present work contributed to the comprehension of the Hg biogeochemical cycle, but further research studies are needed. Des mesures de mercure particulaire (PHg) fractionnées par taille ont été effectuées du 18 novembre 2017 à janvier 2018 à Terra Nova Bay (Antarctique), pour la première fois. Les échantillons ont été collectés tous les 10 jours par un impacteur en cascade à grand volume à six étages avec des classes de taille comprises entre 10 ìm et 0,49 ìm. Les concentrations totales de PHg étaient maximales (87 ± 8pg m-3) en novembre, puis ont diminué à des valeurs d'environ 40% plus basses et sont demeurées presque constantes jusqu'à la fin de la période d'échantillonnage (~ 30 pg m-3). La distribution de masse trimodale des aérosols révèle que de 30% à 90% du PHg total a une taille> 1,0 ìm. Le Hg dans les deux fractions grossières a probablement été produit par l'adsorption d'espèces de Hg oxydé transportées par ...