Precipitation extremes in the Puna of Atacama Desert, Chile: How to manage current and future uncertainty?

Abstract

Chile is one of the Latin American countries most affected by Climate Change. There is a high level of uncertainty regarding the variability of precipitation and its projections in many regions of this country. This poses challenges for climate characterization and for defining strategies to reduce its risks. The study area is the Puna of Atacama Desert, Andean highlands located to the eastern side of the extreme arid lands, a region that concentrates the main copper and lithium mining at word scale, and where meteorological observations are scarce, with missing data and unreliable projections. Considering this data limitations, a daily precipitation database of 35 weather stations was constructed in order to evaluate some extreme precipitation indices that allow establishing changes between 1981-2017, in addition to spatial interpolations based on topography. It is concluded that most of the meteorological stations do not present significant trends of change, e.g. Extremely wet days (R99p), Wet days (RR) and Consecutive wet days (CWD). The index with the highest number of stations with a trend is CDD, which shows an increase in consecutive dry days. One of the main contributions of this research was to expand the number of observations and to generate maps of the spatial distribution of the indices of extremes. We are facing open questions regarding living with uncertainty, and meeting the challenges of maintaining records to increase the levels of certainty of climatic changes.