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Assessment of effects from crop residue field burning on particulate matter air quality in Thailand | |
Author | Thongchai Kanabkaew |
Call Number | AIT Diss. no.EV-11-08 |
Subject(s) | Air quality--Thailand Burning of land--Thailand Crop residues |
Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering in Environmental Engineering and Management, Royal Thai Government |
Publisher | Asian Institute of Technology |
Abstract | In this study, effects of crop residue field burning emissions on PM air quality and atmospheric conditions in BMR have been assessed using both monitoring and modeling tools. The study was divided into 4 tasks addressing: I) the relationship between crop residue field burning and PM concentrations and selected atmospheric properties [net incoming solar radiation (ISR) and horizontal visibility (HV)], 2) the emission inventory (EI) for input data preparation, 3) the CAMx dispersion model performance evaluation and 4) the quantification of impacts from crop residue field burning emission on PM air quality and climate. In Task 1, the number of hotspots detected from the MOD IS satellite, representing the crop residue field burning in BMR, was correlated with level of PMio concentrations. Since the short-lived fires of crop residue burning may not be adequately captured by satellite as hotspots, the satellite aerosol product of AOT was also used to provide a larger spatial coverage of PM levels, sources and transport and also for 3D model evaluation. The 6-year AOT data from 2002-2007 were used to analyze the relationship between PM and atmospheric properties (ISR and HV). The results show that R2 of linear regression between hourly PM10 and AOT were around 0.5 for the clear sky conditions (cloud factor :'.53/10). Strong negative correlation between PM10 and HV were observed with R2 of around 0. 7 while PMio and JSR were not well correlated (R2 of around 0.1 ), but also with a negative slope of the linear regression. The major outcomes of Task 2 include the EI of crop residue field burning for Thailand and the ammonia EI for BMR which were subsequently used to prepare the emission input for CAMx modeling. The results show that rice straw field burning (RSB) was by far the largest contributor to the total crop residue field burning emissions in Thailand. In the base year of2007, the emission estimates from the burning for Thailand, in Gg, were as follows: PM2. 5- l28; PMio-143; S02-3.50; C02-21,400; CO-l,450; NOx-41.7; NH3-58.8; CH4-l32; NMVOC-108; EC-10.4; and OC-53.5. The EI of NHJ in the base year of 2007 was conducted for four predominant sources, i.e. livestock, fertilized soils, biogenic soils and crop residue field burning in BMR. The largest NH3 emission in BMR was from the livestock accounting for 11.8 Gg as NH3, followed by fertilized soils (10.5 Gg), crop residue field burning (2.3 Gg), and biogenic soil emission (l .2E-02 Gg). The CAMx/MM5 model system was used in Task 3 to simulate concentrations of PM10 in BMR with the emission input data prepared from the existing PCD emission database projected to 2007 and the EI for crop residue field burning and NH3 by this study. The simulated 24 hour-average PM10 reasonably captured the daily variation of the observed PM10 better than the hourly values at 5 monitoring stations in BMR. The rough estimation of temporal and spatial emission profiles used in this study may be a reason of the discrepancy. The PM10 simulation results still met the suggested performance statistic for criteria. The spatial distribution of simulated PM also shows consistency with the wind field and the distribution of source emission strength. AOT data available with large spatial coverage were expected to supplement the scattered ground PM10 monitoring data points in the model evaluation but was not that useful. Impacts of crop residue field burning on PM air quality and climate conditions were quantified in Task 4 through the change on the emission of air pollution and climate forcers and simulated PM levels. A considerable reduction in ambient concentrations of Ill PM1o if no crop residue field burning is practiced in BMR as compared to the base case, was found with the maximum reduction in monthly average PM 1o of 6 ug/m3 over the domain. The crop residue field burning in BMR would contribute to the climate forcer emission in C0 2 equivalent of 1,944 Gg for 20-year time horizon and 1,055 Gg for I 00- year time horizon whereas that for the whole country the corresponding value was 55,616 Gg and 30,753 Gg. This could be accounted for 11 % and 16%. respectively of the country total C02 equivalent for all sources while that of BMR was 0.4% and 0.6%, respectively. Future studies should consider application of air quality and climate modeling system to assess the effects in the emission reduction on the regional climate. The results of this study can be useful to raise the public awareness on the potential adverse effects of this emission source and to develop policy to address the crop residue field burning activities. |
Year | 2011 |
Type | Dissertation |
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 and Management (EV) |
Chairperson(s) | Nguyen Thi Kim Oanh |
Examination Committee(s) | Thammarat Koottatep ;Kiyoshi, Honda ;Bond, Tami C. |
Scholarship Donor(s) | Royal Thai Government |
Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2011 |