Ozone Sensitivity and Uncertainty Analysis Using DDM-3D in a Photochemical Air Quality Model
Ozone Sensitivity and Uncertainty Analysis Using DDM-3D in a Photochemical Air Quality Model
复制标题
在光化学空气质量模型中使用 DDM-3D 进行臭氧敏感性和不确定性分析
DOI:
10.1007/978-1-4615-4153-0_19
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发表时间:
2000
期刊:
影响因子:
--
通讯作者:
A. Russell
中科院分区:
文献类型:
--
作者:
Yueh;J. Wilkinson;M. Odman;A. Russell
Sensitivity analysis plays an important role in understanding the response of an environmental system to the variation of model inputs or parameters. This information can be further utilized to explore the model uncertainties introduced from these model inputs and parameters. However, sensitivity analysis has not been used as widely as desired in multidimensional models because of its complexity. A fast and formal sensitivity technique (DDM-3D) has been developed and implemented in the CIT (California/Carnegie Institute of Technology) airshed model to evaluate the sensitivity of predicted pollutant levels to the reaction rate constants of gas-phase photochemical mechanism. The study focuses on the chemical rate constants, which have been identified to be influential to the predicted ozone uncertainty in previous studies. The ozone sensitivities to rate parameters are then computed spatially in a multiday ozone episode, August 27–29, 1987, applied to the Los Angeles area, southern California. It was found that only a limited number of rate constants have a significant influence on ozone predictions. Combined with the sensitivity analysis, a first-order uncertainty was conducted and results indicate that uncertainty of reaction rate constants have significant impacts on the ozone levels. The uncertainty (± lσ) in ozone ranged from 10–35% of predicted levels downwind of Los Angeles and 35–50% for the urban core during afternoon high-ozone hours. In addition to the first-order uncertainty analysis, a Monte Carlo simulation incorporated with Latin Hypercube Sampling (LHS) technique was conducted to assess the importance of non-linearities. It was found that the two approaches gave very similar results. The results also suggest that the overall uncertainty of predicted ozone is highly dominated by the uncertainty of rate constant of HNO3 formation.