Photochemical smog modeling for ozone air quality management in Ho Chi Minh City, Vietnam | |
| Author | Tran Nguyen Quang Huy |
| Call Number | AIT Thesis no.EV-08-40 |
| Subject(s) | Photochemical smog--Vietnam--Ho Chi Minh Air quality management--Vietnam--Ho Chi Minh |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Environmental Engineering and Management |
| Publisher | Asian Institute of Technology |
| Abstract | Being the biggest city in Vietnam with population of more than 6 million people and having economic development rate with GDP increasing index at 112% (in year 2006), Ho Chi Minh City (HCMC) is now facing with a lot of critical environmental pollution problems. Efforts are being put forward to improve environmental quality but pollution seems to still be in the rising trend. This study presents an effort in applying modeling tool for evaluation and forecasting of ozone air quality in HCMC by using the Comprehensive Air Quality Model with Extensions (CAMx) which was driven by the MM5 meteorological model. MM5 was applied in three way nested running with three simulation domains having resolution of 32.4km x 32.4km, 10.8km x 10.8km and 3.6km x 3.6km, respectively. The CAMx model was applied in two way nested running having resolution matching with the two smaller domains of the MM5. The simulation was done for the first two weeks of March 2005 when ozone was high compared to other periods in 2002 - 2005. Maximum hourly ozone concentration during the period varied from 100 to 124 ppb. A preliminary emission inventory of ozone precursors was developed covering all major sources in HCMC: industry, traffic, gasoline station, domestic burning and biogenic emission. Traffic is the major source of air pollutants in HCMC which contributed 49%, 98% and 81 % of the total emission of NOx, CO and VOCs, respectively. MM5 reproduced meteorological parameters, such as temperature, wind speed and wind direction, which were in a reasonable agreement with observed data except for two days of high ozone when the model seriously overestimated wind speed. CAMx generally underestimated ozone concentration especially on these days. When excluding the latter, a better performance in the remaining days were obtained with statistical values MNB, MNE and UPA being -13.4%, 19.2% and -0.55%, respectively, which all meet USEPA suggested criteria. Sensitivity of ozone concentration to its precursor emission reductions was analyzed. The result shows that ozone concentration in HCMC is more sensitive to NOx than to VOCs emission reduction. Further studies should be carried out to improve the emission inventory. More simulation should also be conducted for longer period of time to provide better insights into photochemical smog pollution in the city in order to propose effective ozone air quality management strategies. |
| Year | 2008 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering (EV) |
| Chairperson(s) | Nguyen, Thi Kim Oanh; |
| Examination Committee(s) | Huynh, Trung Luong;Shipin, Oleg V.; |
| Scholarship Donor(s) | Electricity of Vietnam; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2008 |