Atmosfera | 2021
The Negative Impact of Biomass Burning and the Orinoco Low-Level Jet on the Air Quality of the Orinoco River Basin
Abstract
Biomass burning (BB) is a common activity in developing countries and has been identified as a serious air pollution threat. The present work evaluates the air quality of\xa0the largest town in the extensive Colombian savannas (250,000 km 2 ) for the first time, from measurements over three consecutive years (2017-2020). Although the air quality in Villavicencio is good in terms of PM 10 and O 3 \xa0for most of the year, the pollution levels for both pollutants exceed the World Health Organization recommended limits during the dry season (February to April). The combination of the\xa0Orinoco low-level jet (OLLJ) with the BB emissions from the Venezuelan and the Colombian\xa0savannas was identified as the main cause of the poor air quality episodes during the dry\xa0season in this city. Organic carbon derived from reanalysis was identified as the main\xa0component of the high PM 10 concentrations during the dry season. However, mineral dust\xa0and sea salt particles were also found to play an important role in the poor air quality\xa0observed in Villavicencio and likely along the Orinoco river basin region. Finally, between\xa0November and March, the OLLJ was found to be an efficient mechanism for the transport of\xa0air pollutants from the Atlantic Ocean and the savannas regions in the Orinoco River Basin in Venezuela and Colombia\xa0towards southern regions of Colombia, and in some cases, Ecuador.