2019년 수도권 연무사례시 기상모델의 분석 넛징 자료동화가 PM2.5 농도 모의에 미치는 효과

• Published in: 한국대기환경학회지(국문) Vol. 37; no. 2; pp. 231 - 247
• Main Authors: 조성빈(Seong-Bin Cho), 송상근(Sang-Keun Song), 문수환(Soo-Hwan Moon)
• Format: Journal Article
• Language: Korean
• Published: 한국대기환경학회 01.04.2021
• Subjects: 대기과학; Haze event; Wind speed; 2.5< Analysis nudging; PM< SUB> WRF-CMAQ
• ISSN: 1598-7132; 2383-5346
• DOI: 10.5572/KOSAE.2021.37.2.231

In this study, we investigated the effect of assimilated meteorological fields on the numerical simulation of PM2.5 concentrations during the severe haze event observed over the Seoul metropolitan area (SMA) from February 27 to March 6, 2019. The analysis was performed by two sets of simulation experiments: (1) CMAQ simulation with base WRF run (Base) and (2) CMAQ simulation with grid-nudged WRF run (Nudging) that includes four dimensional data assimilation (FDDA) analysis nudging technique. Overall, the meteorological variables (air temperature, wind speed, and relative humidity) of Nudging case showed a higher improvement than those of Base case, especially wind speed. In addition, the PM2.5 concentrations in the Base case were mostly underestimated in the study area compared to the Nudging case. The meteorological improvements contributed greatly to the increase in PM2.5 concentrations in the Nudging case, and thus, showed good agreement with its observed concentrations, especially to the nighttime PM2.5 increase due to the enhancement of atmospheric stability by reduced wind speed. In terms of spatial distributions, high PM2.5 concentrations in the Nudging case (especially March 3~4) were mostly simulated in the western coastal area, northwestern or southwestern areas of the SMA. Significant differences (≥15 μg/m3) in the mean PM2.5 concentrations between the Nudging and Base cases were found mainly in the northwestern and east-southeast areas of the SMA. The enhanced PM2.5 concentrations might be primarily due to the meteorological conditions (e.g., reduced wind speed or wind convergence) and/or the pollutant transport from strong emission sources (e.g., Chinese or local emissions) along northerly/northwesterly winds caused by analysis nudging effect. KCI Citation Count: 0