Open AccessAtmospheric Dynamics and Ozone Cycle during Sea Breeze in a Mediterranean Complex Urbanized Coastal Site
Author(s) -
S. Finardi,
G. Agrillo,
Rita Baraldi,
Giuseppe Calori,
Pantaleone Carlucci,
P. Ciccioli,
A. D’Allura,
Daniele Gasbarra,
Beniamino Gioli,
Vincenzo Magliulo,
Paola Radice,
Piero Toscano,
Alessandro Zaldei
Publication year - 2018
Publication title -
journal of applied meteorology and climatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.079
H-Index - 134
eISSN - 1558-8432
pISSN - 1558-8424
DOI - 10.1175/jamc-d-17-0117.1
Subject(s) - sea breeze , environmental science , ozone , diurnal cycle , atmospheric sciences , mediterranean sea , planetary boundary layer , mesoscale meteorology , climatology , mediterranean climate , forcing (mathematics) , air quality index , boundary layer , atmospheric dynamics , atmosphere (unit) , meteorology , geology , geography , thermodynamics , physics , archaeology
Persistent high pressure conditions over the Mediterranean Basin favor the occurrence of sea breezes that can lead to ozone transport through complex recirculation patterns. These features were investigated during an ozone episode with hourly concentrations exceeding 200 μ g m −3 that occurred on July 2015 in Naples (Italy), one of the largest and densest conurbations in the Mediterranean region. Aircraft measurements were taken at heights from 150 to 1500 m AGL and compared and integrated with high-resolution meteorological and air quality model simulations to investigate local circulation and pollutants dynamics. The integration of airborne measurements, surface observations, and modeling established a framework to assess the photochemical phenomena in the area. Sea breezes and local emissions triggered ozone production at inland areas, causing high concentrations between the coast and the Apennine chain. Ozone was then injected into the upper boundary layer and transported toward the sea by the wind rotation occurring above 500 m AGL, causing a complex vertical layering of concentrations, with maxima between 500 and 800 m AGL. Vertical growth of the ozone concentration profile was also caused by the decrease of the boundary layer depth occurring when the breeze front reached the inland area carrying NO x -rich air from the densely populated coast and favoring titration near the surface. Although the whole airshed was a net ozone producer, local surface concentrations were determined by a complex interaction of atmospheric flow and chemistry at different scales, supporting the need for coordinated efforts to control smog precursors over wide areas.