Was a complete phaseout of the harmful chemicals and substances in the works, our ozone layer looks to be on a path where it can completely heal. This hypothesis was decisively confirmed, first by laboratory measurements and subsequently by direct measurements, from the ground and from high-altitude airplanes, of very high concentrations of chlorine monoxide ClO in the Antarctic stratosphere.
Byincreases in ozone depletion stopped. CFCs have been banned since and the amount of chlorine that is in the atmosphere has been beginning to fall. The ozone hole occurs during the Antarctic spring, from September to early December, as strong westerly winds start to circulate around the continent and create an atmospheric container.
Science is not done by consensus. The relationship between malignant melanoma and ultraviolet exposure is not yet fully understood, but it appears that both UVB and UVA are involved. Thus, higher UVB exposure raises human vitamin D in those deficient in it.
In the s, David Bates and Marcel Nicolet presented evidence that various free radicals, in particular hydroxyl OH and nitric oxide NOcould catalyze this recombination reaction, reducing the overall amount of ozone.
The total mass of ozone in the atmosphere is about 3 billion metric tons.
More and more of such international agreements between countries is necessary to bring down ozone layer depletion. The especially rapid ozone depletion in Antarctica had previously been dismissed as a measurement error. In such conditions the ice crystals of the cloud provide a suitable surface for conversion of unreactive chlorine compounds into reactive chlorine compounds, which can deplete ozone easily.
These cancers are relatively mild and rarely fatal, although the treatment of squamous cell carcinoma sometimes requires extensive reconstructive surgery. At individual level each and everyone also can contribute towards reducing ozone layer depletion.
The process by which the clouds remove NO 2 from the stratosphere by converting it to nitric acid in the PSC particles, which then are lost by sedimentation is called denitrification. This is what which leads to almost 80 percent of the total ozone layer depletion.
The key observation is that, ordinarily, most of the chlorine in the stratosphere resides in "reservoir" compounds, primarily chlorine nitrate ClONO 2 as well as stable end products such as HCl.
There are three types of PSC clouds—nitric acid trihydrate clouds, slowly cooling water-ice clouds, and rapid cooling water-ice nacerous clouds—provide surfaces for chemical reactions whose products will, in the spring lead to ozone destruction.
If stratospheric conditions become more severe cooler temperatures, more clouds, more active chlorineglobal ozone may decrease at a greater pace. Both chlorine and bromine contribute significantly to overall ozone depletion.
Without extensive ozone layer protections, UVB protection would require humans to either live underground, under several meters of water, or wear protective clothing over every inch of our body. The mechanism by which UVB induces these cancers is well understood—absorption of UVB radiation causes the pyrimidine bases in the DNA molecule to form dimersresulting in transcription errors when the DNA replicates.
While there are natural sources for all of these speciesthe concentrations of chlorine and bromine increased markedly in recent decades because of the release of large quantities of man-made organohalogen compounds, especially chlorofluorocarbons CFCs and bromofluorocarbons.
The risks are particularly high for young children, the elderly, and those with asthma or other respiratory difficulties. Antarctic ozone hole[ edit ] The discovery of the Antarctic "ozone hole" by British Antarctic Survey scientists FarmanGardiner and Shanklin first reported in a paper in Nature in May  came as a shock to the scientific community, because the observed decline in polar ozone was far larger than anyone had anticipated.
The only problem is that scientific evidence has proven that these chemicals are a contributing factor to the ozone layer depletion that has been occurring since the invention of CFCs. Ozone in the lower atmosphere contributes to global warming and climate change. Ultraviolet-B solar radiation then dissociates ozone back into an oxygen atom and an oxygen molecule.
Unsourced material may be challenged and removed. Ozone is created when solar ultraviolet-C radiation dissociates an oxygen molecule into two oxygen atoms, which then combine with oxygen molecules to form ozone O3.Now, the ozone layer is beginning to heal, but NASA experts continue to keep an eye on the interactions between what remained of CFC.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains high concentrations of ozone (O 3) in relation to other parts of the atmosphere, although still small in relation to other gases in.
The ozone layer diminishes more each year. As the area of polar ozone depletion (commonly called the ozone hole) gets larger, additional. Ozone layer depletion first captured the attention of the whole world in the latter half ofand since then, a lot of research has been done to find its possible effects and causes.
Various studies have been undertaken to find out possible solutions. Depletion of Ozone Layer essays The issue of whether the people of the world have exaggerated the threat of the ozone depletion has been widely debated. It is an important issue because it concerns health and well being now and tomorrow.
ISSUES AND CONCERNS ABOUT THE OZONE LAYER DEPLETION INTRODUCTION The ozone layer protects the Earth from the ultraviolet rays sent down by the sun.
If the ozone layer is depleted by human action, the effects on the planet could be catastrophic.Download