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Polar areas are the most sensitive targets of climate change. From this perspective, the continuous monitoring of the cryosphere represents a critical need, which, now, we can only partially supply with specific satellite missions. The integration between remote-sensed multi-spectral images and field data is crucial to validate retrieval algorithms and climatological models. The optical behavior of snow, at different wavelengths, provides significant information about the microphysical characteristics of the surface in addition to the spatial distribution of snow/ice covers. This work presents the unmanned apparatus installed at Ny Ålesund (Svalbard) that provides continuous spectral surface albedo. A narrow band device was compared to a full-range system, to remotely sensed data during the 2015 spring/summer period at the Amundsen-Nobile Climate Change Tower. The system was integrated with a camera aimed to acquire sky and ground images. The results confirmed the possibility of making continuous observations of the snow surface and highlighted the opportunity to monitor the spectral variations of snowed surfaces during the melting period. [ABSTRACT FROM AUTHOR]

Abstract: The strong ozone depletion event that occurred in Arctic during spring 2011 was found to cause appreciable reduction in the ozone column (OC) in Europe, even at lower latitudes. The features of this episode have been analysed using the data recorded at 34 ground-based stations located in the European area and compared with the similar events in 2000 and 2005. The results provided evidence that OC as far south as 40°N latitude was considerably influenced by the Arctic ozone loss in spring 2011. The reduction of OC at the northernmost sites was about 40% with respect to the mean value calculated over the previous six-year period, while a similar decrease at the southern extreme ranged between 15 and 18%, and were delayed by nearly two weeks compared to the Arctic region. The ozone distributions reconstructed for the West Europe sector show that the decline of OC lasted from late March to late April 2011. The echo of the Arctic ozone depletion on mid-latitude UV irradiance has been analysed trough model computations that show an increase of the midday erythemal dose by 3–4 SED (1 SED = 100 J m−2) that was slightly higher than at polar regions. On the other hand it was assessed that the biosystems in the northernmost regions were a subject of about 4 times higher UV stress than those at mid-latitudes. Despite indications of an OC recovery, the event examined here shows that the issue of ozone depletion episodes cannot be belittled. [Copyright &y& Elsevier]