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| Titel |
Climatology of pure tropospheric profiles and column contents of ozone and carbon monoxide using MOZAIC in the mid-northern latitudes (24° N to 50° N) from 1994 to 2009 |
| VerfasserIn |
R. M. Zbinden, V. Thouret, P. Ricaud, F. Carminati, J.-P. Cammas, P. Nédélec |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 24 ; Nr. 13, no. 24 (2013-12-18), S.12363-12388 |
| Datensatznummer |
250085891
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| Publikation (Nr.) |
 copernicus.org/acp-13-12363-2013.pdf |
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| Zusammenfassung |
| The objective of this paper is to deliver the most accurate ozone
(O3) and carbon monoxide (CO) climatology for the pure troposphere
only, i.e. exclusively from the ground to the dynamical tropopause on an
individual profile basis. The results (profiles and columns) are derived
solely from the Measurements of OZone and water vapour by
in-service Alrbus airCraft programme (MOZAIC) over 15
years (1994–2009). The study, focused on the northern mid-latitudes
[24–50° N] and [119° W–140° E],
includes more than 40 000 profiles over 11 sites to give a quasi-global
zonal picture. Considering all the sites, the pure tropospheric column
peak-to-peak seasonal cycle ranges are 23.7–43.2 DU for O3 and
1.7–6.9 × 10 18 molecules cm−2 for CO. The maxima of the
seasonal cycles are not in phase, occurring in February–April for CO and
May–July for O3. The phase shift is related to the photochemistry
and OH removal efficiencies. The purely tropospheric seasonal profiles are
characterized by a typical autumn–winter/spring–summer O3 dichotomy
(except in Los Angeles, Eastmed – a cluster of Cairo and Tel Aviv – and the
regions impacted by the summer monsoon) and a summer–autumn/winter–spring CO
dichotomy. We revisit the boundary-layer, mid-tropospheric (MT) and
upper-tropospheric (UT) partial columns using a~new monthly varying MT
ceiling. Interestingly, the seasonal cycle maximum of the UT partial columns
is shifted from summer to spring for O3 and to very early spring for
CO. Conversely, the MT maximum is shifted from spring to summer and is
associated with a summer (winter) MT thickening (thinning). Lastly, the pure
tropospheric seasonal cycles derived from our analysis are consistent with
the cycles derived from spaceborne measurements, the correlation coefficients
being r=0.6–0.9 for O3 and r>0.9 for CO. The cycles observed
from space are nevertheless greater than MOZAIC for O3 (by 9–18 DU)
and smaller for CO (up to 1 × 10 18 molecules cm−2). The
larger winter O3 difference between the two data sets suggests
probable stratospheric contamination in satellite data due to the tropopause
position. The study underlines the importance of rigorously discriminating
between the stratospheric and tropospheric reservoirs and avoiding use of
a~monthly averaged tropopause position without this strict discrimination in
order to assess the pure O3 and CO tropospheric trends. |
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