Climatic trends and impact of climate change on agriculture in an arid Andean valley

Abstract

Little is known about climate change and its impacts for the arid coastal and mountainous regions in northern Chile. The Elqui river basin, part of the Norte Chico of Chile between 27ºS and 33ºS latitude, is located south of the hyper-arid Atacama desert. Despite water scarcity, agricultural development in this region has been enhanced by agronomic practices and the marketing of valuable products. This paper characterizes the actual climate conditions and presents an overview and analyses of past climate variability, and future possible climate trends, emphasizing those relevant to agriculture. Precipitation shows an important decrease during the first decades of the past century. Runoff shows decreasing trends for the first half of the past century and increases for 1960 to 1985. Drought appears to be increasing. Statistical downscaling was accomplished using the Long Ashton Research Station Weather Generator. Both future periods of 2011 to 2030 and 2046-65 showed trends to higher minimum and maximum temperature. The number of hot days (maximum temperature greater than or equal to 30°C) has a strong increasing trend during

Multi-method assessment of reservoir effects on hydrological droughts in an arid region

“…In both, spring and summer hydrological droughts were found in the upstream and naturalised scenario, whereas winter droughts were mainly seen in the downstream (post-dam) and human-influenced scenario. This shift in the timing of droughts due to human-influences is an important deviation from the natural system as it can have implications on ecosystem response and resilience to drought, especially in arid climates where ecosystems are already sensitive to small changes in precipitation and available water (Fiebig-Wittmaack et al, 2012). These results are in agreement with existing studies which found that reservoirs modify the hydrologic regime of rivers, producing a delay of the natural annual cycle of river and provide a buffering capacity (Petts & Gurnell, 2005;López-Moreno et al 2009;Assani et al, 2013) due to increased storage.…”

Glacier meltwater flow paths and storage in a geomorphologically complex glacial foreland: The case of the Tapado glacier, dry Andes of Chile (30°S)

“…Most precipitation (80%) is concentrated in the three austral winter months (JuneAugust) (Bourgin et al, 2012). Recent studies have shown that the dry Andes are currently warming (Falvey and Garreaud, 2009) and that precipitation may decrease or remain stable in the future (Fiebig-Wittmaack et al, 2011).…”

Mass Balance and Climate History of a High-Altitude Glacier, Desert Andes of Chile

“…The existence and development of several mining projects near the headwaters of the main transverse valleys in the region also contribute to the reginal economy but raises environmental and resource equity disputes (Oyarzún and Oyarzún, 2011;Kronenberg, 2013). There is a strong concern that the observed (Falvey and Garreaud, 2009) and predicted (Cabré et al, 2016;Bozkurt et al, 2017) warming trend in the high Andes together with the apparent decreasing precipitation over recent decades (Fiebig-Wittmaack et al, 2012;Quintana and Aceituno, 2012;Schulz et al, 2012) could result in aggravated water stress in the Norte-Chico region. This in turn could exacerbate inter-sector conflicts about water usage and limit future development (Young et al, 2010;Valdés-Pineda et al, 2014).…”