Author(s)

A. Capra, P. Porto & B. Scicolone

Abstract

In this paper, monthly values of rainfall (P) and temperature (T) recorded in Southern Italy (Calabria and Sicily) during the period 1921-2000 are investigated. In particular, a series of 211 raingauge and 53 temperature stations are analysed for evidence of trend by using the linear regression and the Kendall non-parametric test. The tests are applied at a seasonal and annual scale; a spatial analysis is also carried out at both a regional and sub-regional scale in order to check the effect of different sub-areas on these trends. An additional investigation useful for checking the climate change effects on vegetation is also included analysing bioclimatic parameters such as evapotranspiration and aridity index. The results obtained confirmed, for the two investigated regions, the importance of the climatic analysis carried out at a regional scale. In fact, the tests showed for both the P and T records a strong difference between the two investigated regions. In particular, the total annual P showed a decreasing and increasing trend with -344 and 197 mm/100 years respectively in the Tyrrhenian and Ionian sub-regions of Calabria and a decreasing trend with -179 mm/100 years in Sicily. A decreasing trend is evident in the Tyrrhenian sub-region for the mean annual values of Tmax (-3.2 °C/100 years) and Tmin (-2.9 °C /100 years); a different trend is shown in the Ionian sub-region where the mean annual values of T showed an increase of 2.2 and 0.9 °C /100 years for Tmax and Tmin respectively. In contrast, a clear increasing trend (1.8 and 2.2 °C /100 years) is shown for both Tmax and Tmin in Sicily. A detailed analysis involving the calculation of 10-year moving averages, showed a significant change of trending after the 1950s for P and after 1970s for T. Keywords: climate change, precipitation, temperatures, bioclimatic parameters.

Keywords

climate change, precipitation, temperatures, bioclimatic parameters.