Simple model for estimating dry deposition velocity of ozone and its destruction in a polluted nocturnal boundary layer

Abstract

Determining the destructions of both ozone and odd oxygen, O x, in the nocturnal boundary layer (NBL) is important to evaluate the regional ozone budget and overnight ozone accumulation. This work develops a simple method to determine the dry deposition velocity of ozone and its destruction at a polluted nocturnal boundary layer. The destruction of O x can also be determined simultaneously. The method is based on O 3 and NO 2 profiles and their surface measurements. Linkages between the dry deposition velocities of O 3 and NO 2 and between the dry deposition loss of O x and its chemical loss are constructed and used. Field measurements are made at an agricultural site to demonstrate the application of the model. The model estimated nocturnal O 3 dry deposition velocities from 0.13 to 0.19 cm s −1, very close to those previously obtained for similar land types. Additionally, dry deposition and chemical reactions account for 60 and 40% of the overall nocturnal ozone loss, respectively; ozone dry deposition accounts for 50% of the overall nocturnal loss of O x, dry deposition of NO 2 accounts for another 20%, and chemical reactions account for the remaining 30%. The proposed method enables the use of measurements made in typical ozone field studies to evaluate various nocturnal destructions of O 3 and O x in a polluted environment.