The ozone layer is a deep layer in the Earth’s stratosphere that has an altitude of about 6.2 miles and contains a high concentration of ozone molecules. The ozone layer shields the entire Earth from some of the harmful ultraviolet rays that come from the sun. The Earth’s atmosphere is composed of several layers, but the layer that we live in - the “troposphere” – is where most weather occurs. Above the troposphere is the stratosphere which is where most of the effects caused by ozone holes and global warming originate. The ozone layer absorbs 97% to about 99% of the Sun’s medium-frequency ultraviolet light which could otherwise potentially harm and damage exposed life forms on the surface of the Earth. There are three main types of ultraviolet light which are produced from the Sun: UV-A radiation, UV-B radiation and UV-C radiation. UV-A has a long wavelength of about 315 to 400 nanometers from the sun and is considered a “black light” which is not strongly absorbed by the Earth’s ozone. UV-B has a medium wave length of about 315 to 280 nanometers which is mostly absorbed by the ozone layer. Human exposure to UV-B rays increases the risk of skin cancer, a weakened immune system, and cataracts. Additionally, UV-B exposure can also damage single cell organisms, terrestrial plant life, and aquatic ecosystems. UV-C has a short wave length of 280 to 100 nanometers and is completely absorbed by the ozone layer and the atmosphere. UV-C has a variety of positive uses, but the most unique is that it contributes to food, air, and water purification.
For the billion years that the Earth has been here, ozone molecules in the atmosphere have protected life on Earth from the effects of ultraviolet rays that the Sun produces. In the...
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...times as much in the southern hemisphere. The ODS (ozone depleting substances) phase out is still providing significant climate protection benefits. Greenhouse gases, CO2 emissions, climate change, and methane emissions all contribute to the depletion of the ozone layer. By phasing out CFCs, HCFCs and all other ozone depleting substances under the Montreal Protocol, more than 5 giga tons equivalent of CO2 have already been eliminated thus helping to protect our beloved ozone layer (www.grdida.no).
Since the Montreal Protocol’s inception, significant progress has been made to protect and repair the ozone layer. However, throughout the world, people, plants, and animals are still being exposed to harmful UV rays on a daily basis. We must continue to find ways to ensure that every effort is made to work toward a global solution to the depletion of the ozone layer.
The ozone layer is the one that protects living things from the pure ultraviolet rays of the sun.
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.
Tanning affects the human skin through ultraviolet radiation, part of the spectrum of light that omits from the sun to the surface of the earth. Ultraviolet A rays are the longer ultraviolet rays that are projected, and these rays penetrate deep into the layers of skin, causing a tanning effect (Harvard Women's Health Watch, 2). It does this by penetrating into the lower layers of skin, or the epidermis, and triggering cells known as melanocytes to make melanin, the brown pigment that causes tanning (Hyde, Patrice, MD, 1). They account for most of the ultraviolet components emitted by lamps in tanning beds, because they are associated with an almost immediate tanning effect (Brady, Mary S, 2). The shorter rays are ultraviolet B rays, and these rays only reach the outer superficial skin cell layer, also known as the epidermis (Harvard Women's Health Watch, 2). UVB rays, therefore, are the actual cause of sunbur...
0.20 and 0.29 UV-C are harmful to living things. These wavelengths have the ability to cause mutations to living cells, and even kill living cells. It also has the ability to damage your eyes.Most of the UV-C wavelengths are absorbs in the ozone. (But with our ever depleting ozone layer, what happens when the ozone layer is not there anymore?)
Up until the early 1960s, the people of that generation grew up believe that exposure to the sun was healthy and could be used as potential treatments for ailments like acne, for example. The doctors of the early 20th century even promoted the use of the sun’s ultraviolet rays (UV rays) as a treatment for certain strains of tuberculosis. Little did they know the long run consequences of prolonged exposure to the now-labeled ...
Ultraviolet-B (UVB) radiation is a type of ultraviolet (means ‘beyond violet’) radiation that forms a part of the electromagnetic spectrum. Its primary natural source is the sun, but could also be emitted by artificial sources such as UVB lights, excimer lasers and fluorescents. Most UVB produced by sunlight is absorbed by oxygen in Earth’s atmosphere and forms the ozone layer of lower stratosphere. When the amount of ozone in the ozone layer is reduced, more UVB radiation reaches the surface of earth and can cause damaging effects to human health such as skin and eye, nevertheless UVB could also beneficial in some ways when it comes to produce vitamin D and used in medical devices.
As the twenty-first century progresses, it has become increasingly apparent just how many challenges the world faces. Prominent among these concerns are environmental issues, in particular, ozone depletion and climate change. While the international community has been exceptionally successful in its struggle to reduce the production and consumption of chlorofluorocarbons (CFCs), the organic compounds that contribute to the ozone issue, its efforts to tackle climate change have yielded considerably fewer advancements. A number of factors that helped the proceedings of the ozone regime, or campaign, are not applicable to the climate change regime. The issue of limiting CFCs was much less politically and economically charged than that of reducing greenhouse gases (GHGs), which cause the greenhouse effect and the consequent warming of the planet. Climate change has been referred to as the ultimate “tragedy of the commons”, an important metaphor in economics that helps explain why this subject is still at the centre of much heated debate and has yet to be resolved in a manner similar to that of the ozone problem.
“In 2008, 21,000 Canadians died from the effects of air pollution.”(Geduld) Although most of these deaths are from long term exposure to the pollutants there was still “2,682 deaths caused from short term exposure.”(Geduld).“5.5 percent of cardiopulmonary (heart and lung disease related) deaths can be attributed to ground-level ozone exposure, which has increased over the past decade.” (David Suzuki Foundation)
"Ultraviolet Radiation: How It Affects Life on Earth : Feature Articles." Ultraviolet Radiation: How It Affects Life on Earth : Feature Articles. Version 1.0. NASA Earth Observatory, 1 Jan. 2014. Web. 19 Mar. 2014. .
Scientists have performed many different tests and studies to learn more about high exposure to UV. Close observation of cells have shown that sunlight, natural or artificial, can cause mutations or DNA damage in cells. This can lead to further damage which will then be passed down through generations. Another study scientists perform is on animals. Scientist will expose your typical lab animals to UV rays, and this test typically results in skin cancer on the animal. These studies have been performed with UVA, UVB, and UVC, and they have all proven
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.
Audesirk, T. (2003). Life on Earth. In (Ed.), (3rd ed., pp. 581-620). New York: Pearson Custom Publishing - Prentice Hall, Inc..
The sun’s rays contain two types of ultraviolet radiation that reach the skin, UVA and UVB.
Global warming has been a continuous problem that has escalated over time on our planet Earth. The main cause of global warming is because Carbon dioxide and other warming pollutants are gathering in the atmosphere and laying over it like a thick sheet as well as its effect on the ozone layer. This is trapping the sun's heat and causing the planet to grow increasingly warmer as well as a variety of other weather shifts. Over the past 50 years, Earth’s tem...
In 1970, Crutzen first showed that nitrogen oxides produced by decaying nitrous oxide from soil-borne microbes react catalytically with ozone hastening its depletion. His findings started research on "global biogeochemical cycles" as well as the effects of supersonic transport aircraft that release nitrogen oxide into the stratosphere.2 In 1974, Molina and Rowland found that human-made chlorofluorocarbons used for making foam, cleaning fluids, refrigerants, and repellents transform into ozone-depleting agents.3 Chlorofluorocarbons stay in the atmosphere for several decades due to their long tropospheric lifetimes. These compounds are carried into the stratosphere where they undergo hundreds of catalytic cycles with ozone.4 They are broken down into chlorine atoms by ultraviolet radiation.5 Chlorine acts as the catalyst for breaking down atomic oxygen and molecular ozone into two molecules of molecular oxygen.