Ozone in Tropospheric Chemistry: Production, Reactions, and Cycling - Prof. Gunnar Schade, Study notes of Meteorology

Download Ozone in Tropospheric Chemistry: Production, Reactions, and Cycling - Prof. Gunnar Schade and more Study notes Meteorology in PDF only on Docsity! Ozone central to tropospheric chemistry • Dominant producer of the ·OH radical through photolysis in the UV-B – source of atmospheric cleansing capacity • Connected to NOx through the Null-Cycle – diurnal cycle – interdependence and titration • Connected to HOx cycling – in-situ production AND loss from HO2· reactions • Connected to the direct removal of pollutants – ozonolysis – NOx oxidation More reactions relevant for tropospheric ozone • HOx sources … – Photolysis of ozone – Photolysis of formaldehyde and HONO – Ozonolysis of alkenes • … and sinks (in order of importance) NO2 + ·OH (+ M) HNO3 (+ M) HO2· + HO2· (+ M) H2O2 + O2 (+ M) HO2· + ROO· ROOH + O2 HO2· + NO2 (+ M) HO2NO2 (+ M) … and subsequent deposition of HNO3, H2O2, and ROOH Ozone Deposition (effective ozone loss) W ar ne ck , 1 99 9 Ozone budget in the troposphere • transport from stratosphere • in-situ production • in-situ destruction • deposition to the surface W ar ne ck , 1 99 9