dot
Detailansicht
Katalogkarte GBA
Katalogkarte ISBD
Suche präzisieren
Drucken
Download RIS
Hier klicken, um den Treffer aus der Auswahl zu entfernen
Titel Observations and model calculations of trace gas scavenging in a dense Saharan dust plume during MINATROC
VerfasserIn M. Reus, H. Fischer, R. Sander, V. Gros, R. Kormann, G. Salisbury, R. Dingenen, J. Williams, M. Zöllner, J. Lelieveld Link zu Wikipedia
Medientyp Artikel
Sprache Englisch
ISSN 1680-7316
Digitales Dokument URL
Erschienen In: Atmospheric Chemistry and Physics ; 5, no. 7 ; Nr. 5, no. 7 (2005-07-20), S.1787-1803
Datensatznummer 250002981
Publikation (Nr.) Volltext-Dokument vorhandencopernicus.org/acp-5-1787-2005.pdf
 
Zusammenfassung
An intensive field measurement campaign was performed in July/August 2002 at the Global Atmospheric Watch station Izaña on Tenerife to study the interaction of mineral dust aerosol and tropospheric chemistry (MINATROC). A dense Saharan dust plume, with aerosol masses exceeding 500 µg m-3, persisted for three days. During this dust event strongly reduced mixing ratios of ROx (HO2, CH3O2 and higher organic peroxy radicals), H2O2, NOx (NO and NO2) and O3 were observed. A chemistry boxmodel, constrained by the measurements, has been used to study gas phase and heterogeneous chemistry. It appeared to be difficult to reproduce the observed HCHO mixing ratios with the model, possibly related to the representation of precursor gas concentrations or the absence of dry deposition. The model calculations indicate that the reduced H2O2 mixing ratios in the dust plume can be explained by including the heterogeneous removal reaction of HO2 with an uptake coefficient of 0.2, or by assuming heterogeneous removal of H2O2 with an accommodation coefficient of 5x10-4. However, these heterogeneous reactions cannot explain the low ROx mixing ratios observed during the dust event. Whereas a mean daytime net ozone production rate (NOP) of 1.06 ppbv/hr occurred throughout the campaign, the reduced ROx and NOx mixing ratios in the Saharan dust plume contributed to a reduced NOP of 0.14-0.33 ppbv/hr, which likely explains the relatively low ozone mixing ratios observed during this event.
 
Teil von