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.
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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.
15.2) The accumulation of chlorofluorocarbons is responsible for depleting the atmospheric zone. The atmospheric zone has changed in concentration due to human activity. The CFCs release chlorine atoms which react with ozone reducing it to molecular O₂. Following chemical reactions release the chlorine which reacts with other ozone molecules in a catalytic chain reaction. The ozone layer is getting thinner and thinner as stable air at places such as Antarctica allows reaction to continue. The accumulation of CFCs has led to increased UV radiation in sunlight reaching the earth thereby decreasing ozone levels. The global temperature has increased.
The initial step in photochemical reactions is the absorption of a photon by an atom, molecule, free radical or ion. The result of this absorption is strongly dependent on the energy, in other word the wavelength of the photon. Visible and ultraviolet portion of the light is required to start the photochemical reactions. The absorption can generate dissociation, internal rearrangement, flourescence, or excited species. Photochemical smog can occur in any environment where there are large and continuous emissions of primary air pollutants. However specifics of climate and geography play an important role in the persistence and severity of the photochemical smog. Two factors influencing the formation of photochemical smog:
When we think of air pollution we think of the refineries in our cities and the exhaust coming from our cars mostly. In reality there are many more pollutants that we don't think about every day. The six most common air pollutants are; “Carbon monoxide, Nitrogen oxides, Sulphur oxides, Particulate matter, Volatile organic compounds, and Ground-level ozone (nitrogen oxide and Volatile organic compounds reaction)”(David Suzuki Foundation). The fact is people are dying from air pollution and we are doing nothing to make it better, in fact air pollution is getting worse.
Stratospheric ozone absorbs 97-99% of ultraviolet radiation. As this protective layer continues to dissentigrate, human health will suffer. One American dies every hour from skin cancer, a direct result of ozone depletion by anthropogenic chemicals, primarily CFCs, which damage the ozone layer. Alternate chemicals are now being used in the place of CFCs that will not damage statospheric ozone, and there is international recognition of the importance of developing these chemicals. The Montreal Protocol is an international treaty which limits the production of ozone depleting substances. Still, human health is at risk from the deletion of ozone, and the risk factor will continue to rise unless people and industries become more aware of the implications connected with everyday use of chemicals which destroy stratospheric ozone.
People who work or exercise outside for a lengthy period are also vulnerable. Exposure to air pollution increases sensitivity to allergens, impairs lungs, causes asthma attacks and death (Climate change, 2007). Air pollution can cause short-term respiratory symptoms such as coughing, throat irritation, and shortness of breath (California’s drought, 2015). The most harmful pollutants in the air are ozone, fine particles, and air toxics. Since the drought causes warmer weather, levels of ozone or smog increase in the air. Ozone is the principal component of smog and it is dangerous on ground level, which affects human health, crops, and buildings. Ozone smog is formed when vehicle and factory pollution react with sunlight and heat (Climate change, 2007). The lack of storms due to the drought eliminates the natural cleansing effect of precipitation. The low levels of precipitation trap fine particles on ground level. Fine particles in the air are harmful when inhaled and can heighten respiratory illnesses such as asthma and bronchitis. Air toxics are the chemicals in the air that can cause cancer or serious health problems. Mercury, asbestos, and benzene are dangerous air toxics and diesel exhaust particulate is the number one airborne carcinogen in California (California’s drought, 2015). Allergens in the air also affect pollution as
This article states that the ozone hole is diminishing. The credit for this good news is the phasing out of the ozone-depleting chemicals sponsored by the Montreal Protocol (Ozone hole diminishing, Nov). According to this article, the hole reached a peak of 25 million square kilometers, coming down from 28 in previous years since 1998 up to 2006. The article emphasizes the fact that ozone-depleting gases are still being used. The article continues by stating that according to the World Meteorological Organization, the planet will come back to pre-ozone hole conditions between 2060 and 2075 (Ozone hole diminishing, Nov).
The depletion of the ozone layer has been a trending topic after it was first discovered in 1970. The ozone layer is a portion of the earth’s stratosphere which absorbs most of the sun’s UV rays hence preventing cancer and other fatal illness to the skin. It contains high concentrations of O3 and at a constant rate is being broken down and. Since 1970, it has been discovered that about 4% of the ozone layer wears off every decade and is as a result of day-to-day human activity.
While one may visualize air pollution as huge fumes of smoke arising from a chimney and tainting the air of a city, this kind of image is not reflective of how Kansas City appears. However, air pollution is still an issue to consider as it can arise if residents do not act to prevent pollutants into our breathing environment. One of the most prevalent air pollution issues in Kansas City regards the ground level ozone levels. One should note that there are two types of ozone that make up the atmosphere: the ozone layer at a high altitude above the Earth and the ground-level ozone. The first type that is above Earth protects us from ultraviolet radiation from the sun, but the second type is commonly known as ozone pollution or smog (Mid-America Regional Council). Thus, ground-level ozone is a concern when present in at high levels in environments. Before diving in, one should be familiar with how high ground level ozone levels can be harmful. According to Dahl, an adjunct professor affiliated with the department of biological sciences at the University of Notre Dame, clarifies that “ozone is a common urban pollutant that has been linked to
* Nitrogen Oxides are presented through the atmosphere. N2O are very powerful in the chemistry of the troposphere and the stratosphere, and they are very important in ozone production and in the destruction processes. There are a number of sources (the oxidation of N2O like lightning and fossil fuel combustion) whose contribution to NOx concentrations in the upper troposphere is not well measured.
Air pollution is caused by many things such as car fumes, burning of fossil fuels,
The ozone layer diminishes more each year. As the area of polar ozone depletion (commonly called the ozone hole) gets larger, additional ultraviolet rays are allowed to pass through. These rays cause cancer, cataracts, and lowered immunity to diseases.1 What causes the depletion of the ozone layer?
There are many kinds of air pollution. The ones I want to talk about are the ozone, acid rain, carbon monoxide and toxic air contaminants. Ozone is formed when hydrocarbons and nitrogen oxide react in sunlight. Therefore, ozone is at its peak during hot summer days. Exposure to high levels of ozone can have serious consequences on your health. It can cause respiratory disease, loss of pulmonary elasticity, and premature aging of our lungs. Next, is acid rain, which occurs in the atmosphere in the form of sulfur and nitrogen oxide. These pollutants can have serious damaging affects on aquatic, forest and wildlife ecosystems, as well as deterioration of buildings. Carbon monoxide is another form of pollution. It reduces the blood?s ability to carry oxygen. If a human is exposed to higher levels, it can cause chest pains, angina attacks or even death.
Effects on wildlife Animals face effects of air pollution, when toxic chemicals are released in the atmosphere thus causes animals to migrate. Eutrophication also goes as an example of its effect on the environment. Solutions to air pollution Conserve energy A large amount of fossil fuels are being burnt for electricity. To reduce air pollution, we should burn less fuel and avoid wasting electricity. We can also conserve energy by turning off the lights and appliances when we are not using them.
The amount of water that is on earth at any one time remains fairly constant because the water is moving form one reservoir into another such as river to ocean or ocean to atmosphere. This cycle involves the exchange of energy causes a change in temperature. This is why when evaporation occurs, it takes energy from its surroundings and cools the environment. While condensation occurs energy is released and the surrounding environment becomes warmer. The atmosphere is a mixture of nitrogen, oxygen, and other gasses that surround the earth. The atmosphere is made up of five layers known as the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere. The troposphere is the lowest layer of the earth’s atmosphere; it is also where all weather on earth takes place. The stratosphere is the second layer of the atmosphere, right above the troposphere. Above the stratosphere is the mesosphere and above that is the troposphere. The uppermost region of earth’s atmosphere is the exosphere. The air in the exosphere is extremely thin and almost the same as space. One of the many reasons the earths atmosphere is important is because it blocks
As matter of fact, the increasing of greenhouse gases (GHGs) including water vapor (H2O), carbon dioxide (C...