O₃–precursor relationship over multiple patterns of timescale: a case study in Zibo, Shandong Province, China

Abstract. In this study, we developed an approach that integrated multiple patterns of timescale for box modeling (MCMv3.3.1) to better understand the O3–precursor relationship at sites and through continuous observations. A 5-month field campaign was conducted in summer 2019 investigate ozone formation chemistry three a major prefecture-level city (Zibo) Shandong Province northern China. It found relative incremental reactivity (RIR) precursor groups (e.g., anthropogenic volatile organic compounds (AVOCs), NOx) overall consistent terms timescales changed from wider narrower (four patterns: 5-month, monthly, weekly, daily) each site, though magnitudes RIR varied different sites. The time series photochemical regime (using RIRNOx / RIRAVOC as indicator) weekly or daily further showed synchronous temporal trend among sites, while magnitude site-to-site dependent. derived ranking (top 10) individual AVOC species consistency between (i.e., weekly). campaign-averaging regimes sign but non-negligible variability four timescale, which mainly due embedded uncertainty model input dataset when averaging into timescales. This implies utilizing pattern) is useful deriving reliable robust relationships. Our results highlight importance quantifying impact constrain regime, can formulate more accurate policy-relevant guidance O3 pollution control.