Observations and Model Calculations of Trace Gas Scavenging in a Dense Saharan Dust Plume

An intensive field measurement campaign was performed in July / August 2002 at the Izana on Tenerife to study the interaction of mineral dust aerosol and tropospheric chemistry. During an intensive dust event strongly reduced mixing ratios of ROx (HO2, CH3O2 and higher organic peroxy radicals), H2O2, NOx (NO and NO2) and O3 were observed. Box model calculations indicate that the reduced H2O2 mixing rations in the dust polume 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 accomodation coefficient of 3x10-4. However, these heterogeneous reactions cannot explain the low ROx mixing rations observed during the dust event. Reduced ROx and NOx mixing rations in the Saharan dust plume likely explain the relatively low ozone mixing rations observed during this event.

DE REUS Marian;  FISCHER Horst;  SANDER Rolf;  GROS Valerie;  KORMANN Robert;  SALISBURY Gavin;  VAN DINGENEN Rita;  WILLIAMS Jonathan;  ZOELLNER Mathias;  LELIEVELD Jos; 

2005-10-26

European Geosciences Union

JRC30746

https://publications.jrc.ec.europa.eu/repository/handle/JRC30746,