Since sunlight is ubiquitous and forests emit large quantities of volatile organics in the summer, it is the amount of nitrogen oxide that determines whether ozone forms over cities on hot summer days. That NO x is most often supplied by vehicles. In the s and 80s, the United States spent billions trying to limit hydrocarbon emissions, but such efforts had little impact on ground-level ozone because forests were providing plenty of natural hydrocarbons.
Research conducted by William Chameides of Georgia Tech underscored the futility of trying to limit hydrocarbons while ignoring nitrogen oxides. As a result, surface ozone has declined. Not to mention that forests are a natural and crucial part of the environment. Reagan might as well have said, "the sun causes more pollution than automobiles do. GLOP or photochemical smog is only created in areas that receive large amounts of pollution from automobiles and power plants.
Without the input of large amounts of man made nitrogen oxides by cars and power plants, the VOCs released by forests on a summer day have nothing to react with and they do not create any pollution. In reality , photochemical smog is very harmful to trees.
Nominations and campaigning for the RationalWiki Moderator Election is underway and will end on November Before anyone advocates chopping down trees to clean up the air - forgetting, for one, that they give us the oxygen we breathe - scientists caution that whatever forests pump into the air is natural. They also provide shade and scrub many pollutants from the air. Environmental Protection Agency ecologist in San Francisco. Reagan was lampooned by Democrats in for having claimed that 80 percent of air pollution was caused by plants and trees.
Reagan aides later said the then-presidential candidate had been misquoted and was referring only to certain types of pollutants, not to all air pollution. The world's trees, shrubs and other plants do produce massive amounts of hydrocarbons - nine times as much as do automobiles, by some counts.
Those gases, most notably isoprene, are major ingredients of ozone, a lung irritant linked to asthma and other serious respiratory ailments. Ozone formation also requires a second ingredient: nitrogen oxides, a byproduct of the combustion of fossil fuels.
A major source of those gases is the tailpipe of just about every car, truck and bus on the planet. Waft nitrogen oxides - NOx for short - over a forest of isoprene-emitting oaks in, say, the suburbs of Atlanta, throw in a little sunshine and ozone levels will spike. Still, significant numbers of trees of the wrong type, much like a traffic jam of SUVs, can exacerbate a bad ozone situation.
Douglas Costle, administrator of the Environmental Protection Agency, said Reagan may have meant that trees give off nitrous oxides, which they do when they are in the decaying process. However, he said nitrous oxide, also known as laughing gas, is released in small amounts and is not hazardous to humans. Reagan claimed that nitrogen oxides pollution might be beneficial to tubercular patients,' Costle said. At lower levels, they can irritate the lungs, can cause bronchitis and pneumonia Joe Fontaine, president of the Sierra Club, suggested Reagan does not know much about trees, reminding reporters of Reagan's statement as governor of California that 'when you've seen one redwood tree, you've seen them all.
Speth also quoted EPA figures showing man-made sulfur dioxide pollution, largely from old electric power plants, is more than 40 times worse than the sulfur dioxide pollution from the Mount St. Helens volcano. Costle said Mount St.
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