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| Titel |
Attribution and evolution of ozone from Asian wild fires using satellite and aircraft measurements during the ARCTAS campaign |
| VerfasserIn |
R. Dupont, B. Pierce, J. Worden, J. Hair, M. Fenn, P. Hamer, M. Natarajan, T. Schaack, A. Lenzen, E. Apel, J. Dibb, G. Diskin, G. Huey, A. Weinheimer, Y. Kondo, D. Knapp |
| 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 ; 12, no. 1 ; Nr. 12, no. 1 (2012-01-03), S.169-188 |
| Datensatznummer |
250010428
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| Publikation (Nr.) |
 copernicus.org/acp-12-169-2012.pdf |
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| Zusammenfassung |
| We use ozone and carbon monoxide measurements from the Tropospheric Emission
Spectrometer (TES), model estimates of Ozone, CO, and ozone pre-cursors from
the Real-time Air Quality Modeling System (RAQMS), and data from the NASA
DC8 aircraft to characterize the source and dynamical evolution of ozone and
CO in Asian wildfire plumes during the spring ARCTAS campaign 2008. On the
19 April, NASA DC8 O3 and aerosol Differential Absorption
Lidar (DIAL) observed two biomass burning plumes originating from
North-Western Asia (Kazakhstan) and South-Eastern Asia (Thailand) that
advected eastward over the Pacific reaching North America in 10 to 12 days.
Using both TES observations and RAQMS chemical analyses, we track the
wildfire plumes from their source to the ARCTAS DC8 platform. In addition to
photochemical production due to ozone pre-cursors, we find that exchange
between the stratosphere and the troposphere is a major factor influencing
O3 concentrations for both plumes. For example, the Kazakhstan and
Siberian plumes at 55 degrees North is a region of significant springtime
stratospheric/tropospheric exchange. Stratospheric air influences the
Thailand plume after it is lofted to high altitudes via the Himalayas. Using
comparisons of the model to the aircraft and satellite measurements, we
estimate that the Kazakhstan plume is responsible for increases of O3
and CO mixing ratios by approximately 6.4 ppbv and 38 ppbv in the lower
troposphere (height of 2 to 6 km), and the Thailand plume is responsible for
increases of O3 and CO mixing ratios of approximately 11 ppbv and 71 ppbv in
the upper troposphere (height of 8 to 12 km) respectively. However,
there are significant sources of uncertainty in these estimates that point
to the need for future improvements in both model and satellite
observations. For example, it is challenging to characterize the fraction of
air parcels from the stratosphere versus those from the fire because of the
low sensitivity of the TES CO estimates used to mark stratospheric air
versus air parcels affected by the smoke plume. Model transport
uncertainties, such as too much dispersion, results in a broad plume
structure from the Kazakhstan fires that is approximately 2 km lower than
the plume observed by aircraft. Consequently, the model and TES data do not
capture the photochemical production of ozone in the Kazakhstan plume that
is apparent in the aircraft in situ data. However, ozone and CO
distributions from TES and RAQMS model estimates of the Thailand plume are
within the uncertainties of the TES data. Therefore, the RAQMS model is
better able to characterize the emissions from this fire, the mixing of
ozone from the stratosphere to the plume, and the photochemical production
and transport of ozone and ozone pre-cursors as the plume moves across the
Pacific. |
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