Recorded presentation4.1
(Invited Speaker) The effect of locally-emitted CO2 on gases, aerosols, clouds, and health
Mark Z. Jacobson, Stanford University, Stanford, CA
It is now well-established that global warming increases ozone, and some studies show a link between global warming and increases in particulate matter. However, by their nature, all such studies have considered the effect of only globally-emitted and well-mixed greenhouse gases. No study has examined the effect of locally-emitted carbon dioxide on local air pollution or weather. This issue is of interest because measurements indicate that carbon dioxide levels in cities exceed those outside of cities. If locally-emitted carbon dioxide has a negative impact on local air pollution (e.g., ozone and particulate matter primarily), then grounds may exist to regulate carbon dioxide as a local air-pollution precursor, in the same manner that nitrogen oxides, carbon monoxide, and sulfur oxides are regulated. Here, the effects of locally-emitted carbon dioxide on local gas, aerosol, and cloud levels as well as temperature and winds, are examined. Simulations were run for Los Angeles and for California as a whole. Results indicate that locally-emitted carbon dioxide increased local ozone and particulate matter over the period of months to a year, thereby increasing health effects, particularly in Los Angeles. Several important feedbacks to clouds, precipitation, winds, and temperatures were identified. This study, therefore suggests that a basis exists for regulating locally-emitted carbon dioxide as a cause of local air pollution in addition to a cause of global warming.
Session 4, Experimental, field, and modeling studies on aerosol-cloud interactions-II
Tuesday, 13 January 2009, 3:30 PM-5:30 PM, Room 131B
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