Spatio-temporal analysis of droughts in the Iberian Peninsula using complex Climate Networks over precipitation data

Abstract

The Iberian Peninsula is increasingly affected by more frequent and severe droughts (a trend closely linked to climate change),highlighting the need for region-specific studies to assess impacts and guide adaptation strategies. However, the spatio-temporal correlation of drought events across different regions remains poorly understood, and there is a notable lack of methodologies specifically designed to explore these interconnected patterns. This paper analyses precipitation trends and droughts in the Iberian Peninsula (IP) using Climate Networks (CNs). The CN construction method proposed in Berezin et al. (2012) is applied to analyze Reanalysis precipitation data, and to study their spatio-temporal stability and connection with droughts evolution in the IP. The research results reveal two distinct sub-periods in which the precipitation trend behavior differs markedly in the IP. A first period, comprising approximately the years 1940 to 1975, where the drought years are quite anomalous with respect to average years, and a second period, from approximately 1975 onwards, where the comparison of CNs reveals a clear trend to drier years, with lesser differences with drought years. This suggests an intense desertification process in the IP in the last 40 years, consistent with alternative studies based on hydrological processes characterization.