(The Basis of Civilization – Water Science? – Proceedings UNESCO/IAHS/IWHA Symposium held in Rome, December 2003 – IAHS Publication 286, 2004, pp. 217–227).
Southern Italian monthly rainfall and temperature data for the period 1821–2001 were analysed statistically. The data were selected for 126 rain-gauges with the most complete time series. The main study period for which reliable and gap-free annual data are available was 1921–2001. During this period a widespread decreasing trend in annual rainfall was observed for over 96% of the area. This trend was most severe where mean annual rainfall was highest. A decreasing trend of less than –9 mm year−1 was found in the worst case. Analysis of the historical series showed that this trend became more apparent after 1980, the period subjected to two serious droughts (1988–1992 and 2000–2001). In particular, a significant deficit in winter rainfall was found after 1980. Monthly temperatures were also considered. Net rainfall was calculated as a function of monthly rainfall and temperature. Negative trends and the effects of recent droughts were enhanced in terms of net rainfall.
Climate, Drought, Rainfall trends, Time series
