Trophosperic Ozone :: essays research papers

The source of the tropospheric ozone The tropospheric ozone has two major sources. One is intrusion from the stratosphere. Most of ozone in the atmosphere is in the stratosphere and created from solar UV radiation. The stratospheric ozone sometimes flows into the troposphere by the upper layer trough and cut-off low activities. Some part of ozone may subside in the troposphere directly by the Hadley circulation or the Brewer Dobson circulation. Another source is production from photochemical reactions. Ozone is produced from relatively longer-wavelength solar radiation under NOx and non-methane hydrocarbons rich environments. These photochemical reactions possibly bring about photochemical smog in urban area. http://www.asahi-net.or.jp/~wt2y-ttm/what.htm The characteristics of the tropospheric ozone About 8 % of the total column ozone is in the troposphere. The tropospheric ozone also plays an important role in the atmosphere. 1) Ozone is a green house gas and possibly contributes to the global warming. 2) Ozone is harmful for human being and crops in the troposphere. 3) Ozone oxidizes many chemical substances in the troposphere, and controls tropospheric chemistry. The trend of the troposheric ozone Some global monitoring stations show the increase of ozone in the troposphere. It may be a big problem, because if tropospheric ozone increases, it might damage to human beings and many crops, and fairly contribute to the global warming and change the tropospheric chemistry. If the tropospheric chemistry changes, the nature of pollution and acid rain might change. But not all monitoring stations show the increasing trend. We have to monitor the tropospheric ozone at many suitable observation points. This also has the mean to study influence of human activities on Nature. Causes of ground-level ozone Other culprits-besides car and truck exhaust-are gas lawn mowers, over-filling and topping-off a gas tank, which allows vapors to escape, and leaking fuel, which react with sunlight and heat to produce ozone. Alternatives that reduce air pollution and ground-level ozone include using native plants for landscaping rather than a lawn, using an electric or push mower, limiting planting areas for lawns, carpooling and public transportation. Effects on people with preemptive respitoary problems Ground-level ozone can cause flare-ups of asthma, chronic bronchitis, other lung diseases and cardiorespiratory illnesses. Symptoms may take days to appear following exposure. Ground-level ozone can decrease lung function and cause chest tightness and coughing. In addition, ozone and microscopic particulates, small enough to be inhaled into the lungs and "sticky" enough to attract pollens and other allergens, can contribute to asthma and allergy attacks, and make other lung diseases more severe.