A novel method for the assessment of the variations in surface air temperature seasonality of southern Mediterranean region: climatological implications for the Italian Peninsula for the period 1980–2014

The research aimed to evaluate the potential use of the inter-seasonal cooling rate (ISCR) of the temperature seasonality as a climate descriptor. The ISCR methodology is based on deriving an indicator (K index) that estimates the drop in temperature from the warm to cold season (summer–winter). The methodology has been applied to a time-series data of monthly surface air temperature averages of 27 meteorological stations distributed across the Italian Peninsula for the period 1980–2014. The derived K index values were applied as a climate descriptor and used to provide the climate types in the Italian Peninsula. The obtained climate types were compared to climate classes provided by classical climate classification systems of the peninsula such as Köppen. Furthermore, trend analysis of the K index values over the investigated period reveals a general decrease which reflects a decrease in the ISCR; this evidently implies an increase in the surface air temperature of the winter season.