Correlation between the latitudinal profile of the Be air concentration and the Hadley cell extent in the Southern Hemisphere.

The cosmogenic radionuclide Be is one of the best tracers for aerosol transport since its half-life of 53 days is in the time scale of many atmospheric circulation phenomena. In this work, we analyze a 12-years-long daily time-series for the airborne Be concentration for nine air filtering stations in the Southern Hemisphere or close to it. The observed latitudinal distribution of Be concentration, with its maximum at the southern subtropical high-pressure belt, is similar to the one in the Northern Hemisphere.

Assessment of Mn deposition on Earth via accelerator mass spectrometry.

The Mn flux onto Earth is a quantity relevant for different extraterrestrial and astrophysical questions. It is a proxy for related fluxes, such as supernova-produced material or interplanetary dust particles. In this work, we performed a first attempt to assess the Mn flux by measuring the Mn/Be isotopic ratio in a 1400 L sample of molten Antarctic snow by AMS (Accelerator Mass Spectrometry).

(129)I dispersion in Argentina: concentrations in fresh and marine water and deposition fluences in Patagonia.

Measurements of total iodine (I) and iodine-129 ((129)I) concentrations in rivers and lakes of Argentina are presented. Their latitudinal distribution can be explained by taking into account their main sources (oceanic emissions and biomass burning for I, and atmospheric nuclear tests for (129)I), transport mechanisms, and fallout patterns. From the measured (129)I concentrations in the studied lakes, deposition fluences for their catchment areas were estimated.

Iodine-129 in animal thyroids from Argentina.

(129)I and (127)I concentrations in animal thyroids coming from several regions of Argentina were determined by accelerator mass spectrometry (AMS) and gas chromatography (GC), respectively. The measured (129)I/(127)I ratios, ranging from 3 × 10(-12) to 4 × 10(-10), are significantly lower than those typical for areas in the northern hemisphere (10(-10)-10(-7)). The (129)I concentrations show a clear dependence with latitude and season, which can be understood considering tropospheric circulation patterns, possible (129)I sources and regional precipitation rates.

210Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina.

Concentrations of (210)Pb and (137)Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The (210)Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century.