Environmental Engineering Reference
In-Depth Information
8.5 High-Resolution Meteorological Modeling
of California Air Quality Episodes: Model
Intercomparison and Validation
Robert G. Fovell
1
, Bruce Jackson
2
, and Ajith Kaduwela
2
1
Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA, USA
2
California Air Resources Board, Sacramento, CA, USA
Abstract
Mesoscale model simulations of a high ozone summer episode are
validated against surface observations, for the purpose of finding optimal configu-
rations to support air quality studies for present and future climates. Issues involving
validating temperatures are discussed.
Keywords
California CCOS 2000 field study, mesoscale model validation
1. Introduction
Our understanding of poor air quality episodes, and ability to forecast and mitigate
them, depends on proper representation of lower tropospheric meteorology at high
resolution. The employment of mesoscale models in this effort is indicated for
three reasons. First, insufficient observations, especially above the surface, exist to
permit a full understanding of pollution transport. Second, operational models fail
to properly capture complex and important topographic and landuse patterns.
Finally, the need exists to not only understand past and present events but also
anticipate how air quality may respond to regional and large-scale climate change.
Yet, mesoscale models need to be properly tuned and systematically validated.
This work employs two such models - the Weather Research and Forecasting
(WRF) ARW core and the NCAR/Penn State Mesoscale Model, Version 5
(MM5) - to simulate meteorological conditions during the Central California
Ozone Study. This report narrows the focus to model physics selection based on
validation against surface observations.
