Urban modification of natural particulate matter (PM) emissions in Patagonia: A 12-year record of anthropogenic and natural sources from Puerto Madryn, Argentina

Abstract

Dust emissions from arid and semiarid regions influence climate, biogeochemical cycles, and human health. Patagonia is one of the largest dust sources in the Southern Hemisphere, yet the contribution of urban activities to total particulate matter (PM) emissions remains poorly quantified. We analyzed a 12-year record of daily PM concentrations from three sites in Puerto Madryn, Argentina, representing background, urban, and industrial environments. Our objectives were to quantify long-term PM dynamics, identify and distinguish natural and anthropogenic sources using a particle-trajectory model and meteorological data, and assess their relative contributions to PM load. We evaluated temporal variability, meteorological controls, and the origin of PM plumes using the HYSPLIT model. The results show that mean PM concentrations were highest at the industrial site and lowest at the background site, with pronounced peaks during winter months. Trajectory analysis indicated that most PM originated from arid regions west of Puerto Madryn, while local industrial and urban activities contributed substantially during specific events. These findings highlight the combined influence of natural and anthropogenic sources on PM dynamics in coastal Patagonia.