Atmospheric Hydrogen Peroxide (H₂O₂) at the Foot and Summit of Mt. Tai: Variations, Sources and Sinks, and Implications for Ozone Formation Chemistry

Abstract

Hydrogen peroxide (H2O2) acts as a terminal sink for atmospheric HOx radicals (OH and HO2), playing a key role in tropospheric O3 formation. However, there are few field measurements of atmospheric H2O2 to assess its role in O3 formation, especially for the seriously polluted region of the North China Plain. In this study, H2O2 concentrations were measured at the foot of Mt. Tai from May to July 2018 and the summit of Mt. Tai from May to June 2019, with average values of 0.93 ± 1.01 and 2.05 ± 1.20 ppb, respectively. H2O2 exhibited a pronounced diurnal variation with a noon‐peak at the foot of Mt. Tai, which could be well reproduced by a gas‐phase box model with H2O2 dry deposition velocity of 3 cm s−1 included, indicating H2O2 was mainly photochemically produced. Modeling analysis showed H2O2 production at the foot was most sensitive to alkenes and aromatics, while the source and sink for H2O2 were dominated by HO2 recombination and dry deposition, respectively. Compared with the summer‐measurement in 2007, the remarkable elevation of H2O2 at the summit might be ascribed to volatile organic compounds (VOCs) increase and SO2 decline. Both H2O2‐O3 correlation and H2O2/NOz ratio suggested O3 formation at the foot of Mt. Tai was mainly VOC‐sensitive in the early morning and shifted to NOx‐sensitive thereafter. Therefore, reduction of VOCs emission especially for the reactive species of alkenes and aromatics in the morning as well as NOx emission around noontime will be effective for mitigating the serious O3 (as well as H2O2) pollution in Tai'an city.

Examining the implications of photochemical indicators on the O3-NOx-VOC sensitivity and control strategies: A case study in the Yangtze River Delta (YRD), China

“…(Sillman, 1995) California: 5 (Lu and Chang, 1998) Germany: 7.78 (Vogel et al, 1999) Mexico City: 8.75 (Torres-Jardon et al, 2009) This work revisited other photochemical indicators including the surface HCHO/NO2, HCHO/NOy, and NOy. The transition interval of HCHO/NO2 was determined as (0.81, 1.35), showing a higher and wider range than in other work (Jin et al, 2017;Liu et al, 2021;Du et al, 2022), but relatively consistent with Tonnesen and Dennis (2000b). It is worth noting that the values mentioned above are all based on measurements or simulations at the ground level, while column HCHO/NO2 retrieved from satellite measurements are more widely used, with thresholds of (1, 2) (Jin and Holloway, 2015;Jin et al, 2017;Duncan et al, 2010;Wang et al, 2021).…”

“…This study Other studies PH2O2/PHNO3 (0.55, 0.75) US: 0.06 (Tonnesen and Dennis, 2000a) China: 0.2 North China Plain: (0.08, 0.2) (Zhang et al, 2020) East China: (0.30, 1.10) (Du et al, 2022) HCHO/NO2 (surface) (0.81, 1.35) US: (0.8, 1.8) (Tonnesen and Dennis, 2000b) East Asia: (0.5, 0.8) (Jin et al, 2017) East China: (0.36, 0.45) (Du et al, 2022) Yangtze River Delta: (0.55, 1.0) (Liu et al, 2021) HCHO/NOy (0.38, 0.60) US: 0.28 (Sillman, 1995) California: (0.5, 0.9) (Lu and Chang, 1998) Pearl River Delta: 0.41 (Ye et al, 2016) https://doi.org/10. (Sillman, 1995) California: 5 (Lu and Chang, 1998) Germany: 7.78 (Vogel et al, 1999) Mexico City: 8.75 (Torres-Jardon et al, 2009) This work revisited other photochemical indicators including the surface HCHO/NO2, HCHO/NOy, and NOy.…”

“…As H2O2 and HNO3 are very soluble and susceptible to deposition and aerosol formation, the indicator values that involve the two species may change with the meteorological conditions (Castell et al, 2009). However, certain thresholds were often used without considering the variability, such as the range of one to two for HCHO/NO2 (Jin and Holloway, 2015;Tang et al, 2012;Ma et al, 2021).…”

Photochemical Aging of Atmospheric Fine Particles as a Potential Source for Gas-Phase Hydrogen Peroxide

“…NO and SO 2 were measured using a chemiluminescence detector and a pulsed UV fluorescence analyzer, respectively (Model 42i and Model 43i, Thermo). H 2 O 2 was measured using an Aero-Laser 2021 analyzer equipped with a fluorescence detector. ,− After gaseous peroxides were stripped from air to buffered solution (pH = 5.8–6.0), total water-soluble peroxides including H 2 O 2 reacted with p -hydroxyphenyl acetic acid (POPHA) and horseradish peroxidase, yielding a fluorescent dye that can be detected using a fluorescence detector. To separate H 2 O 2 from organic peroxides, the stripping solution was divided into two channels.…”

“…Thus, the H 2 O 2 concentration can be obtained from the signal difference between the two channels. The detection limit of the instrument was about 50 pptv with noise lower than 2% at a full scale. − Calibrations with liquid H 2 O 2 standards (33.3 μg L –1 ) were performed before each experiment.…”