Soot is the common term used to describe a complex mix of graphitic carbon and organic carbon compounds that exist in particulate form. Soot is typically formed during combustion processes, such as forest fires and/or the use of internal combustion engines. Soot forms when carbon containing fossil fuels do not burn completely, and the unburnt hydrocarbons nucleate and then grow into soot particles. Soot particles also allow for condensation and accumulation of other material on its surfaces, such as ash particulates, acidic components, and polycyclic aromatic hydrocarbons.
I was introduced into the messy world of soot during my graduate studies when I first studied the role of soot in the formation of ice clouds in the troposphere (which would have climatic effects), and then looked at the soot emissions in megacities, such as Mexico, including the kind of chemical reactions that occur on the surface leading to chemical modification and eventual removal from the atmosphere. It was easy to realize that soot was a terrible form of anthropogenic pollution that would cause adverse health effects (such as pulmonary and lung diseases and carcinogenic effects), impacted visibility, influenced crops, affected rainfall patterns, and had global climatic impacts.
From time to time I will post clippings here that reflect some of the work that is currently going on in both understanding the sources of soot and how to reduce soot emission, and also on the impact of atmospheric soot on health, environment and related issues. This issue has become mainstream in environmental science in developed countries, and over the next few years it will also become a key issue for the developing countries. My current company, GEO2 Technologies, has also developed a novel materials platform to create filters that remove greater than 98% of soot from exhaust plumes (such as cars, trucks, scooters, generators, industrial sources, power plants, etc).
Soot-infused snow majorly responsible for Arctic warming: Study
Washington, June 7 Researchers at the University of California, Irvine, believe that while the threat of greenhouse emissions exists, soot-infused or dirty snow also contributes majorly to .
If Charlie Zender, an Associate Professor of Earth Ssystem Science at the UCI and co-author of the study, is to be believed,dirty snow contributes to a third or more of Arctic warming.
Zender claims that snow becomes dirty when soot from tailpipes, smoke stacks and forest fires enters the atmosphere and falls to the ground. Soot-infused snow is darker than natural snow. Dark surfaces absorb sunlight and cause warming, while bright surfaces reflect heat back into space and cause cooling.
In the past 200 years, the Earth has warmed about .8 degree Celsius. Dirty snow caused the Earth’s temperature to rise .1 to .15 degree, or up to 19 percent of the total warming, Zender and his claimed.
As far the Arctic region is concerned, the researchers say that In the past two centuries, it has warmed about 1.6 degrees, and added that dirty snow caused .5 to 1.5 degrees of warming, or up to 94 percent of the observed change.
Other human influences on Arctic climate change are particles in the atmosphere, including soot; clouds; and land use. According to the researchers, humans create the majority of airborne soot through industry and fuel combustion, while forest and open-field fires account for the rest.
Previous studies have analyzed dirty snow’s effect on climate, but this is the first to take into account realistic emissions from forest fires in the Northern Hemisphere and how warming affects the thickness of the snow pack.
Dirty snow is also prevalent in East Asia, Northern Europe and Northeastern United States, and Zender believes policymakers could use these research results to develop regulations to mitigate global warming.