Temporal variability of temperature extremes in the Sardinia region (Italy)

In this paper, the temporal tendencies of temperature data from the island of Sardinia (Italy) were analyzed by considering 48 data series in the period 1982-2011. In particular, monthly temperatures (maximum and minimum), and some indices of daily extremes were evaluated and tested to detect trends using the Mann-Kendall non-parametric test. Results showed a positive trend in the spring months and a marked negative trend in the autumn-winter months for minimum temperatures. As regards maximum temperatures, almost all months showed positive trends, although an opposite behavior was detected in September and in the winter months. With respect to the extreme indices, a general increasing trend of the series was detected for the diurnal temperature range (DTR), frost days (FD), summer days (SU25), warm (WSDI) and cold (CSDI) spells. As regards tropical nights (TR20), an equal distribution of positive and negative trends has emerged. Results of the spatial analysis performed on the trend marks suggested that Sardinia's topography could influence temperature variability.