A future of extreme precipitation and droughts in the Peruvian Andes

Abstract

Runoff from glacierised Andean river basins is essential for sustaining the livelihoods of millions of people. By running a high-resolution climate model over the two most glacierised regions of Peru we unravel past climatic trends in precipitation and temperature. Future changes are determined from an ensemble of statistically downscaled global climate models. Projections under the high emissions scenario suggest substantial increases in temperature of 3.6 °C and 4.1 °C in the two regions, accompanied by a 12% precipitation increase by the late 21st century. Crucially, significant increases in precipitation extremes (around 75% for total precipitation on very wet days) occur together with an intensification of meteorological droughts caused by increased evapotranspiration. Despite higher precipitation, glacier mass losses are enhanced under both the highest emission and stabilization emission scenarios. Our modelling provides a new projection of combined and contrasting risks, in a region already experiencing rapid environmental change.

Physically-based modelling of glacier evolution under climate change in the tropical Andes

“…the trends in the original CMIP5 models, while adjusting the absolute magnitude of temperature and precipitation and the number of wet days. Full details of the WRF modelling setup, the bias-correction and the future statistical projections can be found in Potter et al (2023). 130…”

Spatio-Temporal Evolution of Olive Tree Water Status Using Land Surface Temperature and Vegetation Indices Derived from Landsat 5 and 8 Satellite Imagery in Southern Peru

“…The study years show the same trend of drought, except in 2005 when there was a decrease in severe drought and drought, obtaining a higher percentage in moderate drought (Tables 3-5). This is attributed to the presence of the El Niño-Southern Oscillation (ENSO) phenomenon, which manifested itself in the Central Pacific (CP) in 2005, resulting in the absence of drought on the southern coast of Peru [36][37][38]. Studies on drought prediction, globally and in Peru, tend to focus more on the Peruvian coastal regions [38].…”

“…This is attributed to the presence of the El Niño-Southern Oscillation (ENSO) phenomenon, which manifested itself in the Central Pacific (CP) in 2005, resulting in the absence of drought on the southern coast of Peru [36][37][38]. Studies on drought prediction, globally and in Peru, tend to focus more on the Peruvian coastal regions [38]. On the other hand, olive cultivation is in the fruiting phenological stage, a period in which its water needs are critical, requiring constant irrigation to achieve better yield and fruit quality [5,10,11].…”

Farmers’ first rain: investigating dry season rainfall characteristics in the Peruvian Andes

“…In addition, for climatological assessment of our case study findings, we use a previously published convection-permitting WRF dataset for the region ( Potter et al 2023), whichcovers 1980-2018 at 4 km horizontal resolution. The WRF setups between our case studies (henceforth WRF-CASE) and this climatological simulation (WRF-CLIM) differ, adding robustness to process-based findings that are represented in both datasets.…”

“…Based on this representative event, our study proposes a first data-based definition for pushpa rain by comparing its distinct environmental conditions to a typical dry and wet event of the same season. In a second step, we exploit an existing climatological 4 km WRF dataset produced for the Rio Santa valley (in review, Potter et al 2023). It provides temporally-consistent decadal atmospheric and rainfall data, allowing us to quantify pushpa frequency and potential trends therein over the last 39 years .…”