INVESTIGADORES
DIEGUEZ Maria Del Carmen
congresos y reuniones científicas
Título:
First seasonal atmospheric total gaseous mercury (TGM) records in Southern South America: INIBIOMA GMOS Station, Nahuel Huapi National Park.
Autor/es:
DIÉGUEZ MC; GARCÍA PE
Lugar:
Roma
Reunión:
Workshop; GMOS QA/QC Worshop; 2013
Institución organizadora:
CONSIGLIO NAZIONALE DELLE RICERCHE ITALIA
Resumen:
In this presentation we report the first seasonal records of Total gaseous mercury (TGM) in a new mercury monitoring station of the project Global Mercury Observation System of the 7th Frame Program of the European Union located in nahuel Huapi National Park (Lab Fotobiología, INIBIOMA-CONICET). TGM is the sum of gaseous elemental mercury (Hg0; GEM) and gaseous oxidised mercury (GOM), which may constitute from both inorganic and organic gaseous mercury species. Hg0 is generally the most dominating mercury species in the background atmosphere and constitutes often more than 98% of the total gaseous mercury. Automatic TGM instruments use the amalgamation technique to trap gaseous mercury in the air. Exactly determined air volumes are pulled through a cartridge containing an adsorbent (a gold surface), onto which all gaseous mercury quantitatively is adsorbed. The mercury is then thermally desorbed as GEM (Hg0) and detected by a Tekran 2537 B unit which is a Cold Vapour Atomic Fluorescence Spectrometer CVAFS. The TGM concentration is presented as ng of Hg0 per m3, using volumes at standard pressure and temperature. Daily record of TGM in Bariloche fluctuated between 0.6 and 1.7 ng m-3 in a daily basis. The daily pattern found clearly shows lower TGM values during night-time and higher values during daytime, which may reflect photo-oxidation in the lower atmosphere and Hg0 liberation by photo-oxidation from freshwater masses surrounding the station.