Using 3DVAR data assimilation system to improve ozone simulations in the Mexico City basin

[摘要] This study investigates the improvement of ozone(O₃) simulations in the Mexico City basin using athree-dimensional variational (3DVAR) data assimilation system inmeteorological simulations during the MCMA-2003 field measurement campaign.Meteorological simulations from the NCAR/Penn State mesoscale model (MM5)are used to drive photochemical simulations with the Comprehensive AirQuality Model with extensions (CAMx) during a four-day episode on 13–16April 2003. The simulated wind circulation, temperature, and humidity fieldsin the basin with the data assimilation are found to be more consistent withthe observations than those from the reference deterministic forecast. Thisleads to improved simulations of plume position, peak O₃ timing, andpeak O₃ concentrations in the photochemical model. The improvement inO₃ simulations is especially strong during the daytime. The resultsdemonstrate the importance of applying data assimilation in meteorologicalsimulations for air quality studies in the Mexico City basin.

[学科分类] 大气科学