Preprints
https://doi.org/10.5194/acp-2020-673
https://doi.org/10.5194/acp-2020-673

  27 Aug 2020

27 Aug 2020

Review status: this preprint was under review for the journal ACP. A revision for further review has not been submitted.

Evaluating the sensitivity of fine particulate matter (PM2.5) simulations to chemical mechanism in Delhi

Chinmay Jena1, Sachin D. Ghude1, Rachana Kulkarni1, Sreyashi Debnath1, Rajesh Kumar2, Vijay Kumar Soni3, Prodip Acharja1, Santosh H. Kulkarni4, Manoj Khare4, Akshara J. Kaginalkar4, Dilip M. Chate4, Kaushar Ali1, Ravi S. Nanjundiah1,5, and Madhavan N. Rajeevan6 Chinmay Jena et al.
  • 1Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, India
  • 2National Center for Atmospheric Research, Boulder, CO, USA
  • 3India Meteorological Department, Ministry of Earth Sciences, New Delhi, India
  • 4Centre for Development of Advanced Computing (C-DAC), Pune, Maharashtra, India
  • 5Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bengaluru 560 012, India
  • 6Ministry of Earth Sciences, Prithvi Bhavan, Lodhi Road, New Delhi 110003, India

Abstract. Elevated levels of fine particulate matter (PM2.5) during winter-time have become one of the most important environmental concerns over the Indo-Gangetic Plain (IGP) region of India, and particularly for Delhi. Accurate reconstruction of PM2.5, its optical properties, and dominant chemical components over this region is essential to evaluate the performance of the air quality models. In this study, we investigated the effect of three different aerosol mechanisms coupled with gas-phase chemical schemes on simulated PM2.5 mass concentration in Delhi using the Weather Research and Forecasting model with the Chemistry module (WRF-Chem). The model was employed to cover the entire northern region of India at 10 km horizontal spacing. Results were compared with comprehensive filed data set on dominant PM2.5 chemical compounds from the Winter Fog Experiment (WiFEX) at Delhi, and surface PM2.5 observations in Delhi (17 sites), Punjab (3 sites), Haryana (4 sites), Uttar Pradesh (7 sites) and Rajasthan (17 sites). The Model for Ozone and Related Chemical Tracers (MOZART-4) gas-phase chemical mechanism coupled with the Goddard Chemistry Aerosol Radiation and Transport (GOCART) aerosol scheme (MOZART-GOCART) were selected in the first experiment as it is currently employed in the operational air quality forecasting system of Ministry of Earth Sciences (MoES), Government of India. Other two simulations were performed with the MOZART-4 gas-phase chemical mechanism coupled with the Model for Simulating Aerosol Interactions and Chemistry (MOZART-MOSAIC), and Carbon Bond 5 (CB-05) gas-phase mechanism couple with the Modal Aerosol Dynamics Model for Europe/Secondary Organic Aerosol Model (CB05-MADE/SORGAM) aerosol mechanisms. The evaluation demonstrated that chemical mechanisms affect the evolution of gas-phase precursors and aerosol processes, which in turn affect the optical depth and overall performance of the model for PM2.5. All the three coupled schemes, MOZART-GOCART, MOZART-MOSAIC, and CB05-MADE/SORGAM, underestimate the observed concentrations of major aerosol composition (NO3, SO42−, Cl, BC, OC, and NH4+) and precursor gases (HNO3, NH3, SO2, NO2, and O3) over Delhi. Comparison with observations suggests that the simulations using MOZART-4 gas-phase chemical mechanism with MOSAIC aerosol performed better in simulating aerosols over Delhi and its optical depth over the IGP. The lowest NMB (−18.8 %, MB = −27.4 μg/m3) appeared for the simulations using MOZART-MOSAIC scheme, whereas the NMB was observed 32.5 % (MB = −47.5 μg/m3) for CB05-MADE/SORGAM and −53.3 % (MB = −78 μg/m3) for MOZART-GOCART scheme.

Chinmay Jena et al.

 
Status: closed (peer review stopped)
Status: closed (peer review stopped)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
 
Status: closed (peer review stopped)
Status: closed (peer review stopped)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement

Chinmay Jena et al.

Chinmay Jena et al.

Viewed

Total article views: 249 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
173 74 2 249 27 3 7
  • HTML: 173
  • PDF: 74
  • XML: 2
  • Total: 249
  • Supplement: 27
  • BibTeX: 3
  • EndNote: 7
Views and downloads (calculated since 27 Aug 2020)
Cumulative views and downloads (calculated since 27 Aug 2020)

Viewed (geographical distribution)

Total article views: 360 (including HTML, PDF, and XML) Thereof 356 with geography defined and 4 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Latest update: 05 May 2021
Download
Short summary
Simulations of atmospheric particulate matter (PM2.5) with WRF-Chem model with three different aerosol mechanisms coupled with gas-phase chemical schemes are compared to understand the spatial and temporal variability of PM2.5 over the Indo-Gangetic Plain (IGP) in the winter season. All three chemical schemes underestimate the observed concentrations of major aerosol composition and precursor gases over IGP which in turn affect the optical depth and overall performance of the model for PM2.5.
Altmetrics