There have rather puzzling recommendations made recently in which improvements in air quality are recommended as being delayed in order to retain the radiative cooling effect of certain aerosols, particularly sulphates. Examples of such a recommendation are reported in the Climate Science weblogs
This recommendation is made despite evidence presented in the first weblog listed above, for example, that “350,000 excess deaths per year in India and China due to outdoor exposure risk for each 20mg/m3 (of fine aerosols of less than 2,5 microns).” Such a recommendation applies to all types of aerosols which includes aerosols that contribute to radiative cooling (e.g. see Chapter 2 in the 2007 IPCC report and Chapter 2 in the 2005 NRC report for reviews of these negative radiative forcings).
I have worked throughout my career to improve air quality. This includes two terms on the Colorado Air Quality Control Commission where we implemented (and I supported) efforts such as the oxygenated fuels program to reduce atmospheric CO, strictregulations on wood and coal burning in residential fireplaces and stoves, and on asbestos concentrations. I was a member of an NRC committee that rejected an attempt to exempt certain locations such as Fairbanks Alaska from the national CO health standard; see
National Research Council, 2003: Managing carbon monoxide pollution in meteorological and topographical problem areas. The National Academies Press, Washington, DC, 196 pp,
and also an NRC committee to communicate the major concerns of overgrazing, which includes an increase in dust emissions into the atmosphere; see
Committee on Scholarly Communication with the People’s Republic of China, 1992: Grasslands and grassland sciences in Northern China, Office of International Affairs, National Research Council, National Academy Press, Washington, D.C., 214 pp.
I have taught graduate classes in air pollution at the University of Virginia and Colorado State University (even a class on the U.S. Wilderness System in which the preservation of pristine air quality is a major issue that we discussed). I also was on a committee in Fort Collins that mandated that the permit to construct and operate a brewrey near the city require the burning of natural gas rather than coal.
The motivation for all of these activities is to reduce human mortality and morbidity and to minimize negative environmental effects from air pollution.
Thus, when I see attempts to delay implementation of any air quality improvement, which will cost lives, in order to provide a climate effect (i.e. through the delay in reducing sulphate emissions), we need to recognize that the priorities of those making such climate recommendations are misplaced.