Journal Article

PreJuSER-22398

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Observations of ozone transport from the free troposphere to the Los Angeles basin

Neumann, J. A. ; Trainer, M. ; Aikin, K. C. ; Angevine, W. M. ; Brioude, J. ; Brown, S. S. ; de Gouw, J. A. ; Dube, W. P. ; Flynn, J. H. ; Graus, M. ; Holloway, J. S. ; Lefer, B. L. ; Nedelec, P. ; Nowak, J. B. ; Parrish, D. D. ; Pollack, I. B. ; Roberts, J. M. ; Ryerson, T. B. ; Smit, H.FZJ* ; Thouret, V. ; Wagner, N. L.

2012
Union Washington, DC

This record in other databases:  

Please use a persistent id in citations: http://hdl.handle.net/2128/20900  doi:10.1029/2011JD016919

Abstract: Analysis of in situ airborne measurements from the CalNex 2010 field experiment (Research at the Nexus of Air Quality and Climate Change) show that ozone in the boundary layer over Southern California was increased by downward mixing of air from the free troposphere (FT). The chemical composition, origin, and transport of air upwind and over Los Angeles, California, were studied using measurements of carbon monoxide (CO), ozone, reactive nitrogen species, and meteorological parameters from the National Oceanic and Atmospheric Administration WP-3D aircraft on 18 research flights in California in May and June 2010. On six flights, multiple vertical profiles from 0.2-3.5 km above ground level were conducted throughout the Los Angeles (LA) basin and over the Pacific Ocean. Gas phase compounds measured in 32 vertical profiles are used to characterize air masses in the FT over the LA basin, with the aim of determining the source of increased ozone observed above the planetary boundary layer (PBL). Four primary air mass influences were observed regularly in the FT between approximately 1 and 3.5 km altitude: upper tropospheric air, long-range transport of emissions, aged regional emissions, and marine air. The first three air mass types accounted for 89% of the FT observations. Ozone averaged 71 ppbv in air influenced by the upper troposphere, 69 ppbv in air containing emissions transported long distances, and 65 ppbv in air with aged regional emissions. Correlations between ozone and CO, and ozone and nitric acid, demonstrate entrainment of ozone from the FT into the LA PBL. Downward transport of ozone-rich air from the FT into the PBL contributes to the ozone burden at the surface in this region and makes compliance with air quality standards challenging.

Keyword(s): J

Note: Record converted from VDB: 12.11.2012

---

Contributing Institute(s):

1. Troposphäre (IEK-8)

Research Program(s):

1. Atmosphäre und Klima (P23)

Appears in the scientific report 2012

---

Database coverage:
; ; Current Contents - Agriculture, Biology and Environmental Sciences ; Current Contents - Social and Behavioral Sciences ; JCR ; NCBI Molecular Biology Database ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Thomson Reuters Master Journal List ; Web of Science Core Collection

---