The coronavirus disease 2019 (COVID-19) pandemic is the most severe global health and socioeconomic crisis of our time, and represents the greatest challenge faced by the world since the end of the Second World War. The academic literature indicates that climatic features, specifically temperature and absolute humidity, are very important factors affecting infectious pulmonary disease epidemics - such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS); however, the influence of climatic parameters on COVID-19 remains extremely controversial. The goal of this study is to individuate relationships between several climate parameters (temperature, relative humidity, accumulated precipitation, solar radiation, evaporation, and wind direction and intensity), local morphological parameters, and new daily positive swabs for COVID-19, which represents the only parameter that can be statistically used to quantify the pandemic. The daily deaths parameter was not considered, because it is not reliable, due to frequent administrative errors. Daily data on meteorological conditions and new cases of COVID-19 were collected for the Lombardy Region (Northern Italy) from 1 March, 2020 to 20 April, 2020. This region exhibited the largest rate of official deaths in the world, with a value of approximately 1700 per million on 30 June 2020. Moreover, the apparent lethality was approximately 17% in this area, mainly due to the considerable housing density and the extensive presence of industrial and craft areas. Both the Mann–Kendall test and multivariate statistical analysis showed that none of the considered climatic variables exhibited statistically significant relationships with the epidemiological evolution of COVID-19, at least during spring months in temperate subcontinental climate areas, with the exception of solar radiation, which was directly related and showed an otherwise low explained variability of approximately 20%. Furthermore, the average temperatures of two highly representative meteorological stations of Molise and Lucania (Southern Italy), the most weakly affected by the pandemic, were approximately 1.5 °C lower than those in Bergamo and Brescia (Lombardy), again confirming that a significant relationship between the increase in temperature and decrease in virulence from COVID-19 is not evident, at least in Italy.

The Friulian Alps show peculiar meteorologica and climatic features, deriving also from their geographic position between the northern Adriatic Sea to the South, the main Alpine watershed to the North (Tauern Alps) and the Carpathian belt to the East. Furthermore, there are many topoclimatic situations in relation to the geographic setting of the valleys carved between the main reliefs. This makes the Frioulian territory among the wettest in the entire Alpine region, with very abundant snowfall in relation to the moderate average altitude. Thanks to the availability of continuous and fairly homogeneously distributed historical series, a nivological characterization was carried out at the regional scale, with particular attention to the trend of the density of fresh snow, of the number of days with snow thickness higher than 30 cm and the consequent average elevation of the threshold of 100 skiable days (LAN). The ten snow fields under examination are located at elevations between 603 m. (Claut, Carnic Prealps) and 1843 m. (Rifugio Gilberti, Julian Alps); the analysed timespan goes from the winter season 1990-91 to the 2018-19. Surprising data resulted from this analysis. First of all, we noted that the volume mass (Kg /m3), which cannot be correlated with altitude, tends to a very light decrease (about 1.3 km/mc for year) in all the recording stations: this seems to be in contrast with the strong thermal increase that is occurring also on the Frioulian Alps (about 1.1°C in the same time span). Therefore, it’s very probable that in the last few years the thermal characteristics have changed, maybe together with the main origin of the air masses bringing snow in the study area. We also noted for all the stations an increase in the number of days with Hs> 30 cm: consequently, the average elevation of the limit of 100 days with natural ski possible is at about 1780 m a.s.l. and tends to decrease by about 7 meters per year (14 m in the nearby Slovenian Alps), even though it cannot be correlated with the aforementioned positive variation in temperatures and is in disagreement with the corresponding signals calculated for the northern side of the Alps.