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If you choose to follow any links to the abstract and/or complete text of the item listed below, you will be leaving the Strategian Web site. If you wish to return to this page from the Web page you are sent to, please use the Back option of your browser. William L. Chameides and Michael Bergin Soot Takes Center Stage. (... current scientific evidence indicates that Earth's atmosphere is warming. The main factors causing this warming appear to be the greenhouse gases [such as carbon dioxide or CO2]--pollutants that trap the heat coming from the Earth's surface instead of allowing it to radiate out into space. Besides the greenhouse gases, atmospheric aerosols [suspended particulate matter often associated with air pollution and haze] also can affect Earth's climate. Most aerosols cool the atmosphere [as opposed to the effect of greenhouse gases] by increasing Earth's reflectivity, but aerosols containing black carbon [BC]--that is, soot--warm it by absorbing sunlight. Scientific research has suggested that the contribution of BC to global warming may be substantial, perhaps second only to that of CO2. Soot may have its strongest impact on climates in particular regions--such as China and India--where the emissions of black carbon are [relatively] high. Why? BC, by absorbing sunlight, has a slightly different effect on climate than that caused by the greenhouse gases. In addition, unlike most greenhouse gases, BC is short-lived; its concentration varies by orders of magnitude from urban-industrial areas to remote locations ... thus having a larger effect on climates in particular regions as opposed to the global effects of greenhouse gases. This short article also raises questions about past climate change research that has not taken into account the impact of black carbon and how BC can be included in international protocols on climate change since, unlike the emissions of greenhouse gases, BC emissions are largest in developing countries. In other words, do the roles of the developed and developing world in global warming need to be reevaluated? Do global agreements and treaties need to be revised? Finally, the authors state that the two methods currently most often used to measure BC emissions are poorly characterized, nonequivalent techniques. The authors conclude that until [all] these problems are addressed, the issue of BC's role in global warming and what to do about it will be difficult to resolve. Other keywords and phrases -- drought, flood, floods, greenhouse effect, global warming -- from the text of the article; see the bibliography) Science Volume 297, Number 5590 (September 27, 2002): 2214-2215. How to find the above journal, magazine, or other publication? See Step 3: Locate of the Information Strategy for details. Questions? Please let me know. |
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