Green+house+effect+&+ozone+depletion

 Green House effect!

The following power-point talks about the green house effect. enjoy! media type="custom" key="1908069"

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Ozone Depletion

A thin layer of Ozone gas (O3) encircles the earth and prevents about 99% of ultraviolet light (UV) from the sun from reaching the earth.









Substances that have caused a decrease in atmospheric ozone are...

 1. CHLOROFLUOROCARBONS. (CFC'S)   2.   NITROGEN OXIDES

 CFC's IS DEADLY (but of course it won't kill you).

what's CFC? .

CFC stands for Chlorofluorocarbons. These can be found in the atmosphere from the sources of spray cans, deodorants and aerosols.

CFC's reacts with the stratospheric ozone. It contains a weak C-Cl bond that can easily be broken with just UV light in the stratosphere giving highly reactive *CHLORINE FREE RADICALS* these free radicals can react with more than 100,00 molecules of the ozone! this DEPLETES THE OZONE LAYER !

Nitrogen Oxides can be found in the combustion of __hydrocarbons .__ Nitrate oxides reacts with the Ozone to form OXYGEN GAS, thus it interfers with the natural process of the formation of ozone. 

=__ So WHY IS IT DEADLY? it CAUSES CANCER! __= = = __ well, it causes skin burns and skin cancer. ( so that's why sunblock exists!) It also weakens our immune systems which makes us more susceptible to diseases. Others such as effects on weather, it causes the wind and ocean circulations to change.

Ozone depletion increases the amount of UV light striking down onto the earth's surface.

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__ There are also other substances that can be used instead of CFCs, an example of this would be C4H10, and disadvantage to this would be that C4H10 would be more flammable and contribute to global warming (producing CO, particulates as well as hydrocarbons). __ =__ Polar Regions __= The temperatures become very low in winter times. The low temperature causes water vapour to freeze and form ice crystals. However these crystals also contain molecules such as HCl or ClONO2. These produce hypochlorous acid, HClO and chlorine (C2). The sun causes these molecules to break down to produce Cl* radicals which catalyze the destruction of ozone. The largest holes occur during early spring. Also, as the weather warms in the spring, the ice melts and the reaction is no longer possible. Hence, the amount of ozone increases again.

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