Black Carbon Snow Surface Processes Connected to Atmospheric Variables

This work is the results of two experiments performed in Ny-Alesund (Svalbard) during the 2014 and 2016 spring. Two different experiments were performed to evaluate the relation between the atmospheric load of black carbon(BC) and its concentration in surface snow. One experiment focused on the dailyBC concentration changes in the first 10 cm of the snow layer for a total of 80 days, the second with hourly temporal frequency for 3 consecutive days and 3 cm of snow for study the possible fluctuation of BC in surface snow due to the day and night cycle.The atmospheric equivalent BC mass was measured by an Aethalometer, a PSAP and a mini- Aethalometer. Refractory BC concentrations in snow samples were measured with a SP2 (DMT) and the insoluble particles numbers with an Abakus system (Klotz).Statistical modelling was considered to evaluate the relationships between the parameters and the variability of rBC variability in the snow. In both experiments a statistically significant relation was found between the dust content and rBC concentration in snow, indicating common atmospheric and depositional patterns. In the "80 days" experiment a negative relationwas found between the atmospheric and the snow BC, whereas a positive relation between snow rBC content and snow conductivity. The high resolution sampling of the "3 days" experiment allowed detecting a diurnal cycle of the rBC in snow, inversely proportional to solar radiationand snow temperature.