Wildfire smoke in North-America are frequently observed in New York City (NYC, 40.82°N, 73.95°W) area. It is important to investigate the transported smoke mixing with urban planetary boundary layer (PBL) for assessing their impacts on air quality (AQ). This study presents an integrated observation of transported smoke from the Canadian wildfires with co-located elastic-Raman lidar, ozone-DIAL and Coherent Doppler Wind lidar in June 2023. Two episodes of dense smoke are analyzed that show variations of smoke optical properties, ozone (O3) and PM2.5 concentrations during the period of smoke intrusions on June 6-8 and June 29-July 1, 2023. Different advection and vertical mixing processes in the PBL are indicated for the two episodes. Smoke plume mixing in the PBL are indicated that results in large exceedance of National Ambient Air Quality Standard (NAAQS) of PM2.5 concentration. The variations of Angstrom exponent and lidar-ratio indicate different microphysical properties of aged smoke particles. In addition, near-surface O3 mixing ratios decrease for the Episode-1 (June 6-7) due to heavily-dense smoke attenuating sunlight whereas for the Episode-2 (moderately-dense smoke) O3 concentrations increase in the PBL and at near-surface.
Wu et al. (Thu,) studied this question.