Elemental and Mineralogical Composition of the Western Andean Snow (18°S–41°S)

Abstract

The snowpack is an important source of water for many Andean communities. Because of its importance, elemental and mineralogical composition analysis of the Andean snow is a worthwhile effort. In this study, we conducted a chemical composition analysis (major and trace elements, mineralogy, and chemical enrichment) of surface snow sampled at 21 sites across a transect of about 2,500 km in the Chilean Andes (18–41°S). Our results enabled us to identify five depositional environments: (i) sites 1–3 (in the Atacama Desert, 18–26°S) with relatively high concentrations of metals, high abundance of quartz and low presence of arsenates, (ii) sites 4–8 (in northern Chile, 29–32°S) with relatively high abundance of quartz and low presence of metals and arsenates, (iii) sites 9–12 (in central Chile, 33–35°S) with anthropogenic enrichment of metals, relatively high values of quartz and low abundance of arsenates, (iv) sites 13–14 (also in central Chile, 35–37°S) with relatively high values of quartz and low presence of metals and arsenates, and v) sites 15–21 (in southern Chile, 37–41°S) with relatively high abundance of arsenates and low presence of metals and quartz. We found significant anthropogenic enrichment at sites close to Santiago (a major city of 6 million inhabitants) and in the Atacama Desert (that hosts several major copper mines).

A conceptual hydrological model of semiarid Andean headwater systems in Chile

“…Additionally, as shortwave radiation is the dominant flux in the energy balance (Voordendag et al, 2021), characterizing snow albedo variability is important to accurately calculate snowmelt production (Malmros et al, 2018). Recently, several studies have shown the impact of anthropogenic activities in the wider region to increasing the deposition of light-absorbing impurities (e.g., black carbon and dust) which ultimately accelerates surface snowmelt (Alfonso et al, 2019;Rowe et al, 2019;Cordero et al, 2021Cordero et al, , 2022.…”

Toward Better and Healthier Air Quality: Global PM2.5 and O3 Pollution Status and Risk Assessment Based on the New WHO Air Quality Guidelines for 2021

“…The newly established AQG will serve as a crucial tool to mitigate air pollution and climate change. [19] Actually, the distribution disparity of air pollution around the world is becoming larger, [20] particularly in low-income and middle-income countries. In these countries, rapid urbanization and economic growth depend primarily on the burning of fossil fuels, which further increases air pollution.…”

Black carbon in the Southern Andean snowpack

“…BC, commonly referred to as soot, is produced during combustion in diesel engines, coal burning, and residential wood burning, and wildfires (Bond et al 2013). These particles can be transported by near-surface winds flowing from the valleys west of the Andes towards the mountains (Sinclair and MacDonell 2021, Alfonso et al 2019, Gramsch et al 2020, Barraza et al 2021. The prevailing circulation in mid-latitude Andean mountains (mainly westerly airflow) (Garreaud 2009) favors particle transport/dispersion from sources in the Chilean valleys to the Andes.…”

“…Evidence of BC deposition has been found in Andean snow samples collected close to Santiago (a major city of 6 million inhabitants) and in the Atacama Desert (which hosts several major copper mines) (Alfonso et al 2019, Rowe et al 2019. BC darkens the snow, reduces the albedo (increasing the fraction of solar energy absorbed) and accelerates melting (Warren 2019, Kang et al 2020.…”