Evolution of air quality in Santiago: The role of mobility and lessons from the science-policy interface

Abstract

Worldwide, urbanization constitutes a major and growing driver of global change and a distinctive feature of the Anthropocene. Thus, urban development paths present opportunities for technological and societal transformations towards energy efficiency and decarbonization, with benefits for both greenhouse gas (GHG) and air pollution mitigation. This requires a better understanding of the intertwined dynamics of urban energy and land use, emissions, demographics, governance, and societal and biophysical processes. In this study, we address several characteristics of urbanization in Santiago (33.5°S, 70.5°W, 500 m a.s.l.), the capital city of Chile. Specifically, we focus on the multiple links between mobility and air quality, describe the evolution of these two aspects over the past 30 years, and review the role scientific knowledge has played in policy-making. We show evidence of how technological measures (e.g., fuel quality, three-way catalytic converters, diesel particle filters) have been successful in decreasing coarse mode aerosol (PM10) concentrations in Santiago despite increasing urbanization (e.g., population, motorization, urban sprawl). However, we also show that such measures will likely be insufficient if behavioral changes do not achieve an increase in the use of public transportation. Our investigation seeks to inform urban development in the Anthropocene, and our results may be useful for other developing countries, particularly in Latin America and the Caribbean where more than 80% of the population is urban.

Soccer games and record-breaking PM<sub>2.5</sub> pollution events in Santiago, Chile

“…Land-use and orography data are the same as for WRF. For anthropogenic emissions, the HTAP V2 dataset is used which consists of 0.1 • gridded maps of air pollutant emissions for the year 2010 (Janssens-Maenhout et al, 2015). A downscaling is applied to this inventory based on land-use and demographic characteristics, and monthly emissions are split in time down to daily and hourly rates following the methodology of Menut et al (2013).…”

“…2 for the details). A first baseline simulation aiming to reproduce observed concentrations of pollutants is performed using the HTAP anthropogenic emissions inventory (Janssens-Maenhout et al, 2015). This inventory does not account for sporadic emissions such as the ones studied here.…”

Geohistorical records of the Anthropocene in Chile

“…Endorheic basins from northern Chile region are abbreviated as PdT: Pampa del Tamarugal, SdA: Salar de Atacama, SdPN: Salar de Punta Negra. DOI: https://doi.org/10.1525/elementa.353.f1 recurrent anthropogenic fires have seriously degraded water quality and storage, marine/terrestrial biodiversity, soils, biogeochemical cycles and air quality (Barra et al, 2005;Barraza et al, 2017;Casanova et al, 2013;Donoso et al, 1999;Gallardo et al, 2018;Lara et al, 2009;Molina et al, 2017;Schulz et al, 2010).…”

Personal Exposure Estimates via Portable and Wireless Sensing and Reporting of Particulate Pollution

“…A significant body of research has gone into understanding and controlling the chemical and physical transformations that lead to secondary aerosol formation [16][17][18]. Despite the great success of air quality improvement programs implemented in Western cities over the preceding 50 years, urban environments typically have higher levels of particulate pollution compared to rural locations as cities remain global hubs of fossil fuel combustion and direct emissions [19][20][21][22][23]. An emerging threat is found in some of the world's poorest cities as the World Health Organization (W.H.O.)…”