Adjoint sensitivity of inland ozone to its precursors and meteorological and chemical influences

摘要

Adjoint sensitivity analysis of NOx, VOCs, and O3around the south-eastern part of the Korean Peninsula was performed to estimate their contribution to the high O3level in the inland city, Daegu. Weather Research and Forecasting (WRF) and Community Multiscale Air Quality (CMAQ) modeling systems were used to simulate local circulation and a high O3episode day. The adjoint version of the CMAQ model was applied because it is efficient in making decisions for emission control. Areas affecting day time O3concentration in the receptors were investigated at various times. The results show that the transport of precursors (NOxand VOCs) was more important than that of O3itself. The main influence area was extended from a neighboring location to eastern coastal city Pohang, affecting mainly on the same day as the receptor time. Another sensitive area was a remote area south of Daegu, where VOCs emitted on the previous day affected O3concentration at the receptor time in relation with sea-breeze penetration. Sensitivities differed between the lower and upper parts of the boundary layer because of its development during the transport of O3precursors. After the adjoint sensitivity analysis, the influences of meteorological and chemical effects was investigated separately without the chemical reaction module; the results were 61.9% and 38.1%, respectively. This adjoint result provides valuable information for decision making regarding emission control for air quality.