The analysis of a set of climatic time series for central Italy indicates that a rise in temperature and a decrease in average rainfall are taking place. This trend is consistent with the scenarios given by most Global Circulation Models, which predict a temperature rise of up to about 2 ° C over the next 50 years, coupled (in the West Mediterranean) with a decreasing rainfall trend. Regardless of their causes, these climatic variations involve significant geomorphic consequences, the most important probably being soil erosion. In this chapter the phenomenon of soil erosion in a changing climatic environment has been investigated using the Fourier and USLE equations and the monthly rainfall time series for Perugia and Rome, the longest and most reliable time series for central Italy (1886-1995). The analysis indicates that the rainfall coefficients from both equations show a decreasing trend. This implies that with other conditions remaining the same, specific erosion tends to decrease.This indication is consistent with what has happened in the last 3000 years in the Italian Peninsula, when strong erosion in the upper zone of the basins, alluviation in the valleys and progradation of deltas occurred during cool and rainy periods. All this suggest s that if the present climatic trend persists, a further decrease of the rain factors can be anticipated
Some considerations regarding climatic change and specific erosion in Central Italy
DRAGONI, Valter Ulderico;VALIGI, Daniela
2000
Abstract
The analysis of a set of climatic time series for central Italy indicates that a rise in temperature and a decrease in average rainfall are taking place. This trend is consistent with the scenarios given by most Global Circulation Models, which predict a temperature rise of up to about 2 ° C over the next 50 years, coupled (in the West Mediterranean) with a decreasing rainfall trend. Regardless of their causes, these climatic variations involve significant geomorphic consequences, the most important probably being soil erosion. In this chapter the phenomenon of soil erosion in a changing climatic environment has been investigated using the Fourier and USLE equations and the monthly rainfall time series for Perugia and Rome, the longest and most reliable time series for central Italy (1886-1995). The analysis indicates that the rainfall coefficients from both equations show a decreasing trend. This implies that with other conditions remaining the same, specific erosion tends to decrease.This indication is consistent with what has happened in the last 3000 years in the Italian Peninsula, when strong erosion in the upper zone of the basins, alluviation in the valleys and progradation of deltas occurred during cool and rainy periods. All this suggest s that if the present climatic trend persists, a further decrease of the rain factors can be anticipatedI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
