What is the difference between ozone in the varying layers

Several studies have documented the harmful effects of ozone on crop production, forest growth, and human health. The substantial negative effects of surface-level tropospheric ozone from this direct toxicity contrast with the benefits of the additional filtering of UV-B radiation that it provides. What are the environmental issues associated with ozone?

The dual role of ozone leads to two separate environmental issues. There is concern about increases in ozone in the troposphere. Near-surface ozone is a key component of photochemical "smog," a familiar problem in the atmosphere of many cities around the world. Higher amounts of surface-level ozone are increasingly being observed in rural areas as well. There is also widespread scientific and public interest and concern about losses of ozone in the stratosphere.

Ground-based and satellite instruments have measured decreases in the amount of stratospheric ozone in our atmosphere. This phenomenon is known as the Antarctic ozone hole. In the Arctic polar regions, similar processes occur that have also led to significant chemical depletion of the column ozone during late winter and spring in 7 out of the last 11 years. The atmosphere is really a thin layer of gases surrounding the Earth. How thin? Well, imagine a basketball with one layer of aluminum foil around it.

The aluminum foil represents the average thickness of the atmosphere. The atmosphere is divided into regions defined primarily by temperature. The height and temperature of these layers can vary from season to season. Weather occurs in this layer. The next layer up is called the stratosphere. In the stratosphere, temperature increases with altitude. This is because of ozone. When the ozone in this layer absorbs UV light from the sun, it increases in temperature.

In the mesosphere , ozone concentration decreases. Ozone Layer Research and Technical Resources. Information for students about the Ozone Layer. Addressing Ozone Layer Depletion. Adapting to a Changed Ozone Layer. Phasing Out Ozone-Depleting Substances. Managing Refrigerant Emissions. Most atmospheric ozone is concentrated in a layer in the stratosphere, about 9 to 18 miles 15 to 30 km above the Earth's surface see the figure below. Ozone is a molecule that contains three oxygen atoms.

At any given time, ozone molecules are constantly formed and destroyed in the stratosphere. The total amount has remained relatively stable during the decades that it has been measured. The ozone layer in the stratosphere absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface.

UVB is a kind of ultraviolet light from the sun and sun lamps that has several harmful effects. It is a cause of melanoma and other types of skin cancer. It has also been linked to damage to some materials, crops, and marine organisms. The ozone layer protects the Earth against most UVB coming from the sun. It is always important to protect oneself against UVB, even in the absence of ozone depletion, by wearing hats, sunglasses, and sunscreen. However, these precautions will become more important as ozone depletion worsens.

UVB has been linked to many harmful effects , including skin cancers, cataracts, and harm to some crops and marine life. Scientists have established records spanning several decades that detail normal ozone levels during natural cycles. Ozone concentrations in the atmosphere vary naturally with sunspots, seasons, and latitude. These processes are well understood and predictable. Each natural reduction in ozone levels has been followed by a recovery.

Beginning in the s, however, scientific evidence showed that the ozone shield was being depleted well beyond natural processes. When chlorine and bromine atoms come into contact with ozone in the stratosphere, they destroy ozone molecules.

One chlorine atom can destroy over , ozone molecules before it is removed from the stratosphere. Ozone can be destroyed more quickly than it is naturally created. Some compounds release chlorine or bromine when they are exposed to intense UV light in the stratosphere.

Tropospheric ozone, on the contrary, is a so-called secondary pollutant , a photo oxidant which is formed by the interaction of solar radiation with primary polluting precursors.

Tropospheric ozone is a poisonous substance that harms humans, animals and plants. It results from complex chemical reactions , with a substantial role for the following players:. Ozone molecules, mainly found in two layers of our atmosphere.