Influence of meteorological conditions on the negative oxygen ion characteristics of well-known tourist resorts in China

Using negative oxygen ion (NOI) observations, with an hourly resolution, the automatic weather station (AWS), and a comparative analysis of three well-known scenic locations, namely, Zoige Wetland Nature Reserve (ZWNR), Sichuan Panda Nature Habitat (PNH), and Hangzhou West Lake (HWL) Scenic Area was performed and the dynamic mechanisms of typical wetlands in response to a NOI surge were investigated. The findings are as follows. ① At HWL, NOI concentration was higher than in the metropolitan center. The influence of meteorological conditions on NOI in the ZWNR wetland and PNH in southwest China was more significant than that in Hangzhou in the eastern densely populated metropolitan areas. ② Sensitive contribution parameters of microphysical meteorological conditions are given, including the atmospheric condensation rates (fc) and supersaturation (S), as well as the height and amount of low cloud (H0 and M). A parametric model of exponential attenuation driven by the size of water vapor (fog droplets) is given for diagnosing the NOI concentration change in natural wetlands. At the critical threshold of S > 4%, the NOI rapidly increases to the maximum value. ③ Based on parametric principle of the wet aerodynamics of natural wetlands, the NOI meteorological condition index of the quasi-linear relationship with real-time NOI observation is established. The geographical distribution band of the high concentration of NOI in China is given, which meeting with the typical famous wetlands and giant panda habitat NOI characteristics in China. It provides the application prospects for NOI diagnosis and prediction. [Display omitted] •Observations of ZWNR wetland air quality and the mechanism of wetland NOI generation.•Once the supersaturation threshold >4%, NOI increases rapidly nearby the wetlands.•The distribution of NOI in China is given based on theory and actual observations.