Atmos. Chem. Phys. Discuss., 10, 10551-10587, 2010
© Author(s) 2010. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP.
Ozone production during the field campaign RISFEX 2003 in the Sea of Japan: analysis of sensitivity and behavior basing on an improved indicator
Z. Q. Wang, B. Qi, B. Yang, and Y. S. Chen
Key Laboratory of Applied Surface and Colloid Chemistry (Shaanxi Normal University), Ministry of Education, School of Chemistry and Materials Science, Xian 710062, China

Abstract. An improved indicator Φ, based on the present indicator Θ=τOHVOCOHNOx, is developed to determine the sensitivity of ozone production to HC and NOx in the field campaign RISFEX 2003 (RIShiri Fall EXperiment 2003) made in September 2003 at Rishiri island (45.07° N, 141.12° E, and 35 m a.s.l.) in the sea of Japan. The indicator, defined as a ratio of kHC+OH[HC] to kNOx+OH[NOx], has a close correlation with the relative sensitivity (dlnP(O3)/dln[NO] and P(O3)/dln[HC]) which can explicitly give the sensitivity of P(O3) to NO and HC. According to the indicator, four distinctive regimes were obtained in which modeled P(O3) behaviors differently with HC and NOx. At Φ<1, P(O3) is located in Regime I and is greatly sensitive to both HC with a positive correlation and NOx with a negative one. In Regime II (1<Φ<7±3), P(O3) is more sensitive to HC than NOx, but has a similar relationship to HC and NOx. P(O3) is both positively sensitive to HC and NOx in Regime III (7±3<Φ<23±7). For a higher Φ in Regime IV, it was found that P(O3) is greatly sensitive to NOx but nearly insensitive to HC. During the campaign, 91% (247/271) of P(O3) data are located in Regime III and IV, illuminating that NOx is a limiting factor for ozone production. Hence a controlling of NOx emission can be a more efficient strategy for ozone abatement at the site.

Detailed comparisons between the experimental and modeled P(O3) were performed in different regimes and the results show basically an agreement between the two methods. However, the model tended to underestimate P(O3) in Regime II, indicating that an important source of peroxy radicals missed. In Regime IV with low j(O1D), the over-prediction of modeled P(O3) and the elevated monoterpenes implies that the reactions of monoterpenes with O3 may over-predict the formation of peroxy radicals. Budget analysis shows that P(O3) is dominated by the HO2+NO reaction and followed by the MO2+NO reaction in all regimes. Meanwhile, the ratio of the percent contribution of the HO2+NO reaction to the sum of RO2+NO reactions decreases as Φ increases, implying a decrease efficiency of the RO2 to HO2 conversion via the reaction of RO2 with NO. Further analysis ascertain a declining sensitivity of P(O3) to HC but ascending one to NO with Φ shifting from Regime II to Regime IV, according with the results from the indicator. Sensitivity studies for P(O3) are performed to discover the impaction of NOx and monoterpenes on ozone production in different regions and to compare with the indicator representation. Expected results are obtained and are in good agreement with those given by the indicator. Therefore, the indicator can be applicable to illuminate the features of P(O3) sensitivity at the site.

Citation: Wang, Z. Q., Qi, B., Yang, B., and Chen, Y. S.: Ozone production during the field campaign RISFEX 2003 in the Sea of Japan: analysis of sensitivity and behavior basing on an improved indicator, Atmos. Chem. Phys. Discuss., 10, 10551-10587, doi:10.5194/acpd-10-10551-2010, 2010.
Search ACPD
Discussion Paper
    Final Revised Paper