Historical trends and future scenario projection of maximum summer temperatures in the southern hemisphere: central-southern zone of Chile

Abstract

In the context of global climate change, agricultural threats are increasing due to extreme temperatures, significantly affecting crops. This study analyses historical trends in maximum summer temperatures across Chile’s central region, encompassing Santiago, Curicó, Talca, Chillán, and Los Ángeles, and projects potential scenarios for 2024-2026. The methodology involves climatological analysis and linear adjustments to quantify trends. Results indicate declining linear trends in maximum summer temperatures in Santiago and Curicó, stable trends in Talca, and slight declines in Chillán. At the same time, Los Ángeles indicated a notably steeper decrease in 20th century. Conversely, in the 21st century, Santiago, Curicó, and Talca exhibit moderate positive slopes, indicating gradual increases, with Chillán and Los Ángeles displaying more pronounced upward trends. Probability indicators underline the reliability of these temperature projections, ranging from 54% to 66%. This study allows defining maximum critical temperature limits for the physiological development of plants, and provides valuable information on the rate of desertification at the local level. This approach offers quantitative evidence to support agro-economic development planning and health promotion in the context of persistent challenges arising from climate change.