A New Combined Stepwise-Based High-Order Decoupled Direct and Reduced-Form Method To Improve Uncertainty Analysis in PM2.5 Simulations

作者：Huang, Zhijiong; Hu, Yongtao; Zheng, Junyu^*; Yuan, Zibing; Russell, Armistead G.^*; Ou, Jiamin; Zhong, Zhuangmin

来源：Environmental Science & Technology, 2017, 51(7): 3852-3859.

DOI：10.1021/acs.est.6b05479

• RIVER DELTA REGION
• AIR-QUALITY MODELS
• SENSITIVITY-ANALYSIS
• PHOTOCHEMICAL MODELS
• SOURCE APPORTIONMENT
• EMISSION REDUCTIONS
• BIOLOGICAL-SYSTEMS
• OZONE
• CHINA
• INVENTORY

The traditional reduced-form model (RFM) based on the high-order decoupled direct method (HDDM), is an efficient uncertainty analysis approach for air quality models, but it has large biases in uncertainty propagation due to the limitation of the HDDM in predicting nonlinear responses to large perturbations of model inputs. To overcome the limitation, a new stepwise-based RFM method that combines several sets of local sensitive coefficients under different conditions is proposed. Evaluations reveal that the new RFM improves the prediction of nonlinear responses. The new method is applied to quantify uncertainties in simulated PM2.5 concentrations in the Pearl River Delta (PRD) region of China as a case study. Results show that the average uncertainty range of hourly PM2.5 concentrations is -28% to 57%, which can cover approximately 70% of the observed PM2.5 concentrations, while the traditional RFM underestimates the upper bound of the uncertainty range by 1-6%. Using a variance-based method, the PM2.5 boundary conditions and primary PM2.5 emissions are found to be the two major uncertainty sources in PM2.5 simulations. The new RFM better quantifies the uncertainty range in model simulations and can be applied to improve applications that rely on uncertainty information.

• 出版日期2017-4-4
• 单位华南理工大学