Understanding air pollution dynamics of Antalya Manavgat forest fires: a WRF-Chem analysis

Abstract

This study investigates the air pollution dynamics of the Antalya Manavgat forest fires in Turkey, using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem v4.4.2) and Fire INventory from NCAR (FINN v2.5) boundary fire emission data for the period between 28 July 2021 and 6 August 2021. It focuses on the synoptic and microscale atmospheric conditions during the fire event. The research also delves into the micrometeorological factors, particularly examining the Foehn effect’s influence in intensifying the initial fire conditions through 3D trajectory modeling and surface chart analysis. The study assesses the performance of the WRF-Chem model in predicting aerosol optical depth (AOD), particulate matter (PM₁₀), and various meteorological variables. This assessment utilized diverse re-sampled and interpolated satellite products, including MODIS MAIAC and Sentinel-5P NRTI AER AI. The Manavgat air quality and meteorological station, situated near the fire, proved highly effective in modeling atmospheric parameters, with strong correlations in AOD (0.93), AAI (0.81), and ground-level PM₁₀ (0.82), indicating accurate predictions of particulate pollution levels. The station was also ranked as the second most accurate in modeling overall meteorological conditions. The complex meteorological conditions led to significant discrepancies between ground-measured PM and AOD. The study attempts to elucidate these differences using 3D plume modeling and cross-sectional analysis. Notably, a low-pressure system was identified as a key factor in the vertical expansion of the fire plume, enabling it to reach heights of up to six kilometers above sea level (ASL). Lastly, satellite imagery from August 6 and 7, 2021, reveals persistent aerosol levels in eastern Antalya, driven by atmospheric transport of smoke and particulate matter from local and distant fires, including remnants from the extinguished Manavgat forest fire, as well as fires in Muğla and Greece, carried by cyclonic atmospheric movements over the gulf of Antalya.