What Causes the Atmospheric H2O2 Profile Difference between Urban Beijing and Rural Hebei Province?

Abstract:

Based on the 2013 field observation, we found that the peak concentration of hydrogen peroxide (H₂O₂) in summer was clearly at urban Beijng delayed compared to rural Hebei Province. The modeling results showed that the change of NO emission rate, planetary boundary layer height and dry deposition velocity could not explain the delayed concentration peak of H₂O₂ at urban Beijing. When the aqueous reaction between H₂O₂ and organics was added in the model, there was a better agreement between the modeled and observed phenomena. Combining the detection of hydroxymethyl hydroperoxide (HOCH₂OOH) observed during the nighttime at urban Beijing, we proposed that the aqueous phase reaction between H₂O₂ and organics on aerosols caused the delayed concentration peak of H₂O₂ at urban Beijing.