Urban air quality model inter-comparison study (UMICS) for improvement of PM2.5 simulation in greater Tokyo Area of Japan

Hikari Shimadera*, Hiroshi Hayami, Satoru Chatani, Tazuko Morikawa, Yu Morino, Yasuaki Mori, Kazuyo Yamaji, Seiji Nakatsuka, Toshimasa Ohara

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


The urban model inter-comparison study (UMICS) was conducted in order to improve the performance of air quality models (AQMs) for simulating fine particulate matter (PM2.5) in the Greater Tokyo Area of Japan. UMICS consists of three phases: the first phase focusing on elemental carbon (UMICS1), the second phase focusing on sulfate, nitrate and ammonium (UMICS2), and the third phase focusing on organic aerosol (OA) (UMICS 3). In UMICS2/3, all the participating AQMs were the Community Multiscale Air Quality modeling system (CMAQ) with different configurations, and they similarly overestimated PM2.5 nitrate concentration and underestimated PM2.5 OA concentration. Various sensitivity analyses on CMAQ configurations, emissions and boundary concentrations, and meteorological fields were conducted in order to seek pathways for improvement of PM2.5 simulation. The sensitivity analyses revealed that PM2.5 nitrate concentration was highly sensitive to emissions of ammonia (NH3) and dry deposition of nitric acid (HNO3) and NH3, and PM2.5 OA concentration was highly sensitive to emissions of condensable organic compounds (COC). It was found that PM2.5 simulation was substantially improved by using modified monthly profile of NH3 emissions, larger dry deposition velocities of HNO3 and NH3, and additionally estimated COC emissions. Moreover, variability in PM2.5 simulation was estimated from the results of all the sensitivity analyses. The variabilities on CMAQ configurations, chemical inputs (emissions and boundary concentrations), and meteorological fields were 6.1-6.5, 9.7-10.9, and 10.3-12.3%, respectively.

Original languageEnglish
Pages (from-to)139-152
Number of pages14
JournalAsian Journal of Atmospheric Environment
Issue number2
Publication statusPublished - 2018 Jun 1
Externally publishedYes


  • Air quality simulation
  • Nitrate
  • Organic aerosol
  • Sensitivity analysis
  • Variability in simulation

ASJC Scopus subject areas

  • Environmental Science(all)
  • Atmospheric Science


Dive into the research topics of 'Urban air quality model inter-comparison study (UMICS) for improvement of PM2.5 simulation in greater Tokyo Area of Japan'. Together they form a unique fingerprint.

Cite this