136
L. T. Molina et al.
wood-burning stoves) were used to represent primary pollutants from anthropogenic
sources. The tracers are converted to hourly PM 2.5 concentrations using an observationally based calibration, which reduces substantially the computation time relative
to a full chemistry model. The conversion considers processes occurring in some
of these cities, including contribution of stoves by city, weekend effect, and temperature dependence. The forecasting system has been successfully implemented;
the advanced information about pollutant concentrations has enabled the local government to make contingency-based emission restrictions, thus preventing severe
pollution events similar to those occurring during the 2015 pollution season. As a
consequence, there were 36 pre-emergency and emergencies for PM 2.5 in 2013 but
only 2 in 2017.
21.4 Conclusion
The experiences of Mexico City and Santiago demonstrate that air quality measurements and modeling studies are essential for improving our understanding of air
pollution and its impacts, as well as providing sound scientific basis for policy makers
to design effective emission reduction strategies for public health and environmental
protection. Many of the emission reduction measures implemented in both cities also
provide climate co-benefits, e.g., stricter emission standards for diesel vehicles and
banning of wood-burning stoves will reduce black carbon, one of the key short-lived
climate forcers; and new electric bus fleet will cut greenhouse gases substantially.
Recently, many Chinese cities, including the two large megacities Beijing and
Shanghai, have been suffering serious air pollution. Ambient air particulate matter
and household air pollution from solid fuel used are two of the leading risk factors of mortality in China. Through scientific research for understanding the factors
that influence air pollution, and regional coordinated air pollution control actions
implemented by the Chinese government authority, the concentration of atmospheric
pollutants in several major cities have decreased substantially. Nevertheless, air pollution levels still exceed China’s own air quality standards. Chinese government has
continued to develop and implement emissions reduction strategies and has allocated
significant resources to fight air pollution.
Currently, many urban centers, especially in the developing world, are facing
similar challenges of population growth and economic development. The examples
presented in this study illustrate that with appropriate planning, dedicated scientific
research, robust emissions control policies, and effective access to advanced technologies and financial support, these urban centers also have the opportunities to
manage their growing population and development sustainably while protecting the
environment.
L. T. Molina et al.
wood-burning stoves) were used to represent primary pollutants from anthropogenic
sources. The tracers are converted to hourly PM 2.5 concentrations using an observationally based calibration, which reduces substantially the computation time relative
to a full chemistry model. The conversion considers processes occurring in some
of these cities, including contribution of stoves by city, weekend effect, and temperature dependence. The forecasting system has been successfully implemented;
the advanced information about pollutant concentrations has enabled the local government to make contingency-based emission restrictions, thus preventing severe
pollution events similar to those occurring during the 2015 pollution season. As a
consequence, there were 36 pre-emergency and emergencies for PM 2.5 in 2013 but
only 2 in 2017.
21.4 Conclusion
The experiences of Mexico City and Santiago demonstrate that air quality measurements and modeling studies are essential for improving our understanding of air
pollution and its impacts, as well as providing sound scientific basis for policy makers
to design effective emission reduction strategies for public health and environmental
protection. Many of the emission reduction measures implemented in both cities also
provide climate co-benefits, e.g., stricter emission standards for diesel vehicles and
banning of wood-burning stoves will reduce black carbon, one of the key short-lived
climate forcers; and new electric bus fleet will cut greenhouse gases substantially.
Recently, many Chinese cities, including the two large megacities Beijing and
Shanghai, have been suffering serious air pollution. Ambient air particulate matter
and household air pollution from solid fuel used are two of the leading risk factors of mortality in China. Through scientific research for understanding the factors
that influence air pollution, and regional coordinated air pollution control actions
implemented by the Chinese government authority, the concentration of atmospheric
pollutants in several major cities have decreased substantially. Nevertheless, air pollution levels still exceed China’s own air quality standards. Chinese government has
continued to develop and implement emissions reduction strategies and has allocated
significant resources to fight air pollution.
Currently, many urban centers, especially in the developing world, are facing
similar challenges of population growth and economic development. The examples
presented in this study illustrate that with appropriate planning, dedicated scientific
research, robust emissions control policies, and effective access to advanced technologies and financial support, these urban centers also have the opportunities to
manage their growing population and development sustainably while protecting the
environment.