Formaldehyde record from Lys glacier firn core, Monte Rosa massif (Italy)

Formaldehyde content within the first 16 m of Lys Glacier firn core (Monte Rosa massif, Italy) was determined by a sensitive spectrofluorimetric method in flow injection analysis. The formaldehyde concentration range of all analysed samples was 3.8–24.8 μg l −1, with 11.1 μg l −1 mean concentration and 10.7 μg l −1 median concentration. These values were found to be in agreement with other measurements carried out in high- and mid-latitude glaciers. Due to the exceptionally high annual snow accumulation rate at Lys Glacier sampling site (3.79 m w.e.), most formaldehyde is preserved, at least for the earlier metres of deposition. The general agreement between the formaldehyde profile and other parameters typically used as seasonal markers suggested a similar seasonal behaviour for formaldehyde in high snow accumulation alpine sites.