Characterization of temperature and precipitation fields over Sardinia with principal component analysis and singular spectrum analysis

Abstract

A climatic analysis of temperature and precipitation fields in the Sardinia region is developed. The main purpose of this work is the characterization of temperature and precipitation fields to better understand Sardinia's climate. Principal component analysis (PCA) and singular spectrum analysis (SSA) have been applied to maximum and minimum temperature and to cumulative daily precipitation data collected in the Sardinia region during the period 1951–1992. It is shown that the most significant temporal and spatial portion of temperature fields are described by the first principal component of PCA; SSA of such a first principal component reveals a 38 day oscillation in the region, related to the oscillations observed for planetary waves in the Northern Hemisphere. Precipitation fields are well represented by the first three principal components of PCA. The cluster analysis of those principal components shows the plurimodality of precipitation distribution and the existence of conditions of a high total precipitation localized in Eastern Sardinia. © 1997 The Royal Meteorological Society.