Climate Change in Chile: An Analysis of State-of-the-Art Observations, Satellite-Derived Estimates and Climate Model Simulations

Abstract

Although there is a reasonably large body of work focusing on South American climate, few studies focus on just Chile and even fewer consider climate processes operating over longer timescales, such as those at which climate change becomes apparent. This paper provides an overview of Chilean present-day and future climate, needed to plan for potential impacts of climate change. Firstly, present-day climate conditions are assessed using a number of observational rainfall and temperature datasets. All available GCMs are then examined, to firstly assess their ability to simulate climate during the end of the 20 th century and secondly to examine their projections during the 21 st century. The results of the present day analysis show a showing general agreement in spatial and temporal patterns of rainfall and temperature, between the datasets. When assessing the models' ability to simulate observed rainfall and temperature, the results suggest that although the majority captures the spatial and temporal patterns, there are significant differences between models. When assessing future projections, the results suggest that over the next ~30 years, most GCMs show either no change in rainfall or a small reduction; however there is a lack of agreement regarding the sign of change, suggesting high uncertainty. For temperature, most models agree on a warming trend. This is also true for the longer-term, with most GCMs suggesting a small rainfall decrease by 2100 but a large temperature increase. Lastly, it is suggested that this temperature increase is due to an increase in minimum temperatures, which may have implications for certain frost-sensitive crops.