269
10
Photochemical Air
Pollution Modeling:
Toward Better Air
Quality Management
Carlos Borrego, Ana Isabel Miranda,
and Joana Ferreira
CONTENTS
10.1 Introduction .................................................................................................. 269
10.2 Photochemical Air Pollution Modeling ........................................................ 270
10.3 Case Study .................................................................................................... 274
10.3.1 Methodology ..................................................................................... 275
10.3.2 Emission Ceiling Scenarios .............................................................. 276
10.3.3 Evaluation of the Model Performance .............................................. 277
10.3.4 PTEN Scenario Results .................................................................... 281
10.4 Final Comments ............................................................................................ 282
Acknowledgments .................................................................................................. 282
References .............................................................................................................. 283
10.1 INTRODUCTION
On July 26, 1943, The Los Angeles Times reported that a pall of smoke and fumes had
descended on Downtown Los Angeles cutting visibility to three blocks. Striking in
the midst of a heat wave, it gripped workers and residents who suffered with an eyestinging, throat-scraping sensation. It also left them with the realization that something had gone terribly wrong in their city, normally praised for its sunny climate.
This episode was the trigger for the fi rst U.S. program for air pollution in Los
Angeles in 1947. Since then a long road has been covered and nowadays scientifi c
knowledge about photochemical smog is stable, and it is even possible to forecast
photochemical pollutants, such as ozone levels, a day in advance (Vautard et al.,
2000; Monteiro et al., 2005a). In simple words, ozone can be considered as a secondary pollutant formed alongside the chemical reactions between precursors such
as nitrogen oxides (NO x ) or volatile organic compounds (VOCs), in the presence of
solar radiation.
© 2010 by Taylor and Francis Group, LLC
10
Photochemical Air
Pollution Modeling:
Toward Better Air
Quality Management
Carlos Borrego, Ana Isabel Miranda,
and Joana Ferreira
CONTENTS
10.1 Introduction .................................................................................................. 269
10.2 Photochemical Air Pollution Modeling ........................................................ 270
10.3 Case Study .................................................................................................... 274
10.3.1 Methodology ..................................................................................... 275
10.3.2 Emission Ceiling Scenarios .............................................................. 276
10.3.3 Evaluation of the Model Performance .............................................. 277
10.3.4 PTEN Scenario Results .................................................................... 281
10.4 Final Comments ............................................................................................ 282
Acknowledgments .................................................................................................. 282
References .............................................................................................................. 283
10.1 INTRODUCTION
On July 26, 1943, The Los Angeles Times reported that a pall of smoke and fumes had
descended on Downtown Los Angeles cutting visibility to three blocks. Striking in
the midst of a heat wave, it gripped workers and residents who suffered with an eyestinging, throat-scraping sensation. It also left them with the realization that something had gone terribly wrong in their city, normally praised for its sunny climate.
This episode was the trigger for the fi rst U.S. program for air pollution in Los
Angeles in 1947. Since then a long road has been covered and nowadays scientifi c
knowledge about photochemical smog is stable, and it is even possible to forecast
photochemical pollutants, such as ozone levels, a day in advance (Vautard et al.,
2000; Monteiro et al., 2005a). In simple words, ozone can be considered as a secondary pollutant formed alongside the chemical reactions between precursors such
as nitrogen oxides (NO x ) or volatile organic compounds (VOCs), in the presence of
solar radiation.
© 2010 by Taylor and Francis Group, LLC