Spatiotemporal variability of temperature in Friuli-Venezia Giulia (north-eastern Italy)

Alpine mountainous regions of northern Italy, constituting one of the major mountain areas in Europe, have been identified among the main vulnerable areas to climate change of the continent. In fact, over the last century, global warming has caused all Alpine glaciers in Europe to recede as well as triggered changes in rain and snowfall patterns shortening snow seasons and causing glaciers to recede. Within this context, in this study, the spatiotemporal variability of temperatures in Friuli-Venezia Giulia (north-eastern Italy) has been evaluated by means of 34 monthly series for the period 1940-2011, for which data are freely available online. Indeed this region is characterized by a mountainous northern part, belonging to the Southern Alps, and a southern side touched by the Adriatic Sea. In particular, a trend analysis, at annual, seasonal and monthly scales, was performed on the minimum and maximum values through the Mann-Kendall test. Moreover, the application of the Theil-Sen estimator allowed us to quantify the magnitude of the increase/decrease in the temperature values. The results evidenced an overall increase of the temperatures in both the minimum and the maximum values, mainly detected in the summer months, even though in some stations located in the alpine and pre-alpine areas an opposite trend has been identified.