Central Chile faces changing rainfall patterns and water security risks

Central Chile is facing a shifting hydrological landscape characterized by decreasing total precipitation volumes and more concentrated rainfall events. While recent frontal systems have brought significant water to various parts of the country, experts warn this does not signal a reversal of long-term climatic trends.

Miguel Fernández, a researcher from the GEOOS project at the Pontificia Universidad Católica de Valparaíso, notes that historical records from the Faro Punta Ángeles station in Valparaíso show much more abundant rainfall during the last century. Previously, winter frontal systems arrived with a frequency of at least once per week, a pattern that has changed drastically in recent decades.

A primary driver of this transformation is the South Pacific Semi-permanent Anticyclone. Climate change has strengthened and expanded this high-pressure center, creating an atmospheric block that hinders the movement of frontal systems toward central Chile. Additionally, rainfall in autumn and spring has decreased significantly, with the remaining precipitation tending to occur in shorter, more intense periods.