Ozone production during the field campaign RISFEX 2003 in the sea of Japan: analysis of sensitivity and behaviour based on an improved indicator

Abstract

Abstract. The ratio Φ=kHC+OH[HC]/kNOx+OH[NOx] is used as an indicator for the sensitivity of ozone production (P(O3)) to HC and NOx in the field campaign RISFEX 2003 (RIShiri Fall EXperiment 2003) at Rishiri Island (45.07° N, 141.12° E, and 35 m a.s.l.) in the sea of Japan during September 2003. Four different sensitivity regimes are obtained based on the indicator. The sensitivity is found to show a distinctive pattern in each regime. In Regime I (Φ<1), P(O3) almost linearly increases with increasing HC and almost linearly decreases with increasing NOx. In Regime II (1