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Titel |
Summertime stratospheric processes at northern mid-latitudes: comparisons between MANTRA balloon measurements and the Canadian Middle Atmosphere Model |
VerfasserIn |
S. M. L. Melo, R. Blatherwick, J. Davies, P. Fogal, J. Grandpré, J. McConnell, C. T. McElroy, C. McLandress, F. J. Murcray, J. R. Olson, K. Semeniuk, T. G. Shepherd, K. Strong, D. Tarasick, B. J. Williams-Rioux |
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 ; 8, no. 7 ; Nr. 8, no. 7 (2008-04-11), S.2057-2071 |
Datensatznummer |
250006035
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Publikation (Nr.) |
copernicus.org/acp-8-2057-2008.pdf |
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Zusammenfassung |
In this paper we report on a study conducted using the Middle Atmospheric
Nitrogen TRend Assessment (MANTRA) balloon measurements of stratospheric
constituents and temperature and the Canadian Middle Atmosphere Model
(CMAM). Three different kinds of data are used to assess the
inter-consistency of the combined dataset: single profiles of long-lived
species from MANTRA 1998, sparse climatologies from the ozonesonde
measurements during the four MANTRA campaigns and from HALOE satellite
measurements, and the CMAM climatology. In doing so, we evaluate the ability
of the model to reproduce the measured fields and to thereby test our
ability to describe mid-latitude summertime stratospheric processes. The
MANTRA campaigns were conducted at Vanscoy, Saskatchewan, Canada (52° N,
107° W) in late August and early September of 1998, 2000, 2002 and 2004.
During late summer at mid-latitudes, the stratosphere is close to
photochemical control, providing an ideal scenario for the study reported
here. From this analysis we find that: (1) reducing the value for the
vertical diffusion coefficient in CMAM to a more physically reasonable value
results in the model better reproducing the measured profiles of long-lived
species; (2) the existence of compact correlations among the constituents,
as expected from independent measurements in the literature and from models,
confirms the self-consistency of the MANTRA measurements; and (3) the 1998
measurements show structures in the chemical species profiles that can be
associated with transport, adding to the growing evidence that the
summertime stratosphere can be much more disturbed than anticipated. The
mechanisms responsible for such disturbances need to be understood in order
to assess the representativeness of the measurements and to isolate
long-term trends. |
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