Impact of Sea Breeze Dynamics on Atmospheric Pollutants and Their Toxicity in Industrial and Urban Coastal Environments

Abstract

Sea breeze (SB) phenomena may strongly influence air quality and lead to important effects on human health. In order to study the impact of SB dynamics on the properties and toxicity of aerosols, an atmospheric mobile unit was deployed during a field campaign performed in an urbanized and industrialized coastal area in Northern France. This unit combines aerosol samplers, two scanning lidars (Doppler and elastic) and an air-liquid interface (ALI, Vitrocell®) in vitro cell exposure device. Our study highlights that after the passage of an SB front, the top of the atmospheric boundary layer collapses as the thermal internal boundary layer (TIBL) develops, which leads to high aerosol extinction coefficient values (>0.4 km−1) and an increase of PM2.5 and NOx concentrations in the SB current. The number-size distribution of particles indicates a high proportion of fine particles (with diameter below 500 nm), while the volume-size distribution shows a major mode of coarse particles centered on 2–3 µm. Individual particle analyses performed by cryo-transmission scanning electron microscopy (cryo-TSEM)-EDX highlights that submicronic particles contained a high fraction of secondary compounds, which may result from nucleation and/or condensation of condensable species (vapors or gaseous species after photo-oxidation). Secondary aerosol (SA) formation can be enhanced in some areas, by the interaction between the SB flow and the upper continental air mass, particularly due to the effect of both turbulence and temperature/humidity gradients between these two contrasting air masses. Potential areas of SA formation are located near the ground, during the SB front passage and in the vicinity of the SB current top. During the sea breeze event, an increase in the oxidative stress and inflammation processes in exposed lung cells, compared to the unexposed cells, can also be seen. In some instances, short singularity periods are observed during SB, corresponding to a double flow structure. It consists of two adjacent SB currents that induce an important increase of the TIBL top, improving the pollutants dispersion. This is associated with a substantial decrease of aerosol mass concentrations.

Investigation of Coastal Atmospheric Boundary Layer and Particle by Unmanned Aerial Vehicle under Different Land-sea Temperature

“…If the wind blew from the sea and a ABL turning point exists below 500 m during the daytime, at the height of this point, as indicated by lidar, a TIBL is formed (Wei et al, 2018). This indicated the formation of TIBL is very common over coastal areas (Boyouk et al, 2011;De Tomasi et al, 2011;Huang et al, 2016b;Augustin et al, 2020). It is worth noting that the height of TIBL by lidar was relatively higher than that by UAV.…”

“…In the Indian east coastal region, seasonal variation of TIBL height is relatively weak, with maximum TIBL height occurring during winter and minimum height during summer (Reddy et al, 2020). The TIBL can impact coastal pollution dispersion, which results in high concentrations of air pollutants near the surface (Lin et al, 2001;Boyouk et al, 2011;Augustin et al, 2020;Aslam et al, 2021;Yang et al, 2022). The growth of a TIBL could bring ozone-rich air aloft under onshore wind conditions into the layer, subsequently increasing the surface ozone concentrations farther inland (Lin et al, 2007).…”

A Framework for Sea Breeze Front Detection from Coastal Regions of India Using Morphological Snake Algorithm

“…Our proposed system is similar to (11) with addition of morphological operators. Dynamics of sea breeze is studied in (12). Penetration of Sea breeze causes a change in atmospheric components.…”

Impact of the Nocturnal Low-Level Jet and Orographic Waves on Turbulent Motions and Energy Fluxes in the Lower Atmospheric Boundary Layer

“…Wind profiles were measured using a scanning Doppler wind lidar (LEOSPHERE, Windcube WLS 100) and a sonic anemometer (model USA-1, Metek GmbH). The pulsed Doppler lidar operates at 1543 nm and uses a heterodyne technique to measure the Doppler shift of laser radiation backscattered by the aerosols (Augustin et al 2020). The wind speed is estimated from the Doppler shift at different vertical levels.…”