Observation of smoke plume and PBL interaction with ground-based lidar in summer 2023 in New York City

Smoke plumes from the wildfire in western US and Canada were observed in the eastern US, making potential impacts on ground air quality in the regional and continental scales. Using a synergistic lidar profiling observation for aerosol, ozone and wind, we present the case study on the wildfire transport and interaction with the urban planetary boundary layer (PBL) in New York City (NYC) area. The satellite, AERONET measurements and model product indicate the dense smoke plumes are transported from the Canadian wildfires. Multiple layers of smoke plumes and concurrently high-level of ozone were observed at CCNY site on July 17, 2023. The smoke entrainment into PBL is indicated when the PBL height grows up to 2-km altitude in NYC urban area. The ground-level ozone and PM2.5 show a coincident and dramatic increase with the hourly average ozone at 95 ppb and PM2.5 at 40-50 ug/m3 at CCNY site. However, at the coastal area, ozone and PM2.5 at the near-surface are low since the smoke plumes are aloft above the PBL (the MLH is at 1.2 km altitude). Thus, strong convection in the urban PBL and the entrainment at the PBL top provide favorable conditions for the smoke mixing down to the surface-level.