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| Titel |
Measurements of HCl and HNO3 with the new research aircraft HALO - Quantification of the stratospheric contribution to the O3 and HNO3 budget in the UT/LS |
| VerfasserIn |
Tina Jurkat, Stefan Kaufmann, Christiane Voigt, Andreas Zahn, Hans Schlager, Andreas Engel, Harald Bönisch, Andreas Dörnbrack |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250080438
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| Zusammenfassung |
| Dynamic and chemical processes modify the ozone (O3) budget of the upper troposphere/lower
stratosphere, leading to locally variable O3 trends. In this region, O3 acts as a strong
greenhouse gas with a net positive radiative forcing. It has been suggested, that the
correlation of the stratospheric tracer hydrochloric acid (HCl) with O3 can be used to quantify
stratospheric O3 in the UT/LS region (Marcy et al., 2004). The question is, whether the
stratospheric contribution to the nitric acid (HNO3) budget in the UT/LS can be determined
by a similar approach in order to differentiate between tropospheric and stratospheric sources
of HNO3.
To this end, we performed in situ measurements of HCl and HNO3 with a newly
developed Atmospheric chemical Ionization Mass Spectrometer (AIMS) during the TACTS
(Transport and Composition in the UTLS) / ESMVal (Earth System Model Validation)
mission in August/September 2012. The linear quadrupole mass spectrometer deployed
aboard the new German research aircraft HALO was equipped with a new discharge source
generating SF5- reagent ions and an in-flight calibration allowing for accurate, spatially
highly resolved trace gas measurements. In addition, sulfur dioxide (SO2), nitrous acid
(HONO) and chlorine nitrate (ClONO2) have been simultaneously detected with the AIMS
instrument.
Here, we show trace gas distributions of HCl and HNO3 measured during a North-South
transect from Northern Europe to Antarctica (68Ë N to 65Ë S) at 8 to 15 km altitude and
discuss their latitude dependence. In particular, we investigate the stratospheric ozone
contribution to the ozone budget in the mid-latitude UT/LS using correlations of HCl with
O3. Differences in these correlations in the subtropical and Polar regions are discussed. A
similar approach is used to quantify the HNO3 budget of the UT/LS. We identify unpolluted
atmospheric background distributions and various tropospheric HNO3 sources in specific
regions.
Our observations can be compared to data from remote sensing instruments. Further, they
will help to validate global chemistry-climate models to gain a better understanding of the
trace gas distribution in the UT/LS.
Marcy, T. P., Fahey, D. W., Gao, R. S., Popp, P. J., Richard, E. C., Thompson, T. L.,
Rosenlof, K. H., Ray, E. A., Salawitch, R. J., Atherton, C. S., Bergmann, D. J., Ridley, B. A.,
Weinheimer, A. J., Loewenstein, M., Weinstock, E. M., and Mahoney, M. J.: Quantifying
stratospheric ozone in the upper troposphere with in situ measurements of HCl, Science, 304,
261-265, 2004. |
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