Observation of summer heat waves on the planetary boundary layer and air quality in the New York City region

Air pollution and heatwave episodes pose serious public health concerns in highly populated urban environment such as New York City (NYC) area. In this work, we present an observation-based analysis of the heatwave effect on the urban planetary-boundary-layer (PBL) and air quality (i.e. ozone and PM_2.5) in summer in NYC and down-wind coastal regions in Long Island, NY and Connecticut. Observations include a multi-wavelength elastic-Raman lidar, ceilometers, and wind lidars, and a thermodynamic microwave profiler to characterize the PBL structure and its diurnal variation over the heatwave time periods during the Long Island Sound Tropospheric Ozone Study (LISTO summer 2018). We show variations and differences of the PBL height (PBLH) in NYC and its coastal vicinity. The ozone exceedance and PM2.5 enhancement are clearly demonstrated from both the ground observations and model. Furthermore, we compare the NAQFC forecast modeling ozone, PM2.5 and PBLH to the ground observations. The results indicate good consistency in the strong convective daytime but large bias in the late afternoon and night-time, which might be associated with the exacerbated urban heat effects.