Reduction of snow albedo from vehicle emissions at Portillo, Chile

• Published in: Cold regions science and technology Vol. 146; pp. 43 - 52
• Main Authors: Cereceda-Balic, Francisco, Vidal, Víctor, Moosmüller, Hans, Lapuerta, Magín
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2018
• ISSN: 0165-232X; 1872-7441
• DOI: 10.1016/j.coldregions.2017.11.008

Only scarce literature exists on the effect of direct deposition of vehicle particulate matter emissions onto snow surfaces with well-quantified sources and atmospheric conditions. Local emissions from vehicles in the surroundings of ski resorts not only reduce the whiteness of the snowy landscape affecting the attractiveness to visitors, but also modify the onset of snowmelt and thus the environmental equilibrium of the local area and of the surrounding region. The changes in albedo observed at Portillo, in the Chilean Andes, were an increase of around 0.17units after a heavy snowfall (20cm accumulation), an increase of around 0.07 after a prolonged lighter snowfall (10cm accumulation), and a mean decrease of around 0.08units per day with heavy traffic (around 2000 vehicles per day). Other parameters such as wind velocity and direction did not greatly affect the snow albedo during this study because the wind direction was fairly constant due to the terrain restriction. It is difficult to estimate how much the snow metamorphism and melting contributed to the observed decrease. The albedo changes observed are helpful to confirm the close cause-effect relationship between these parameters and the snow albedo, and to foresee that traffic restriction may allow for more stable snowpack conditions. The case study presented here can be extrapolated to other vehicle-contaminated snow areas, thus examining their contribution to snow radiative forcing and climate change at multiple scale. •Increase in albedo was around 0.08units per decimetre of daily snow accumulation.•Decrease in albedo due to heavy traffic was around 0.08units per day.•Eventual traffic restrictions stabilize snowpack conditions at Chilean Andes.•Daily trends for snow albedo were confirmed by comparison with modelled results.