Ozone Depletion

By: Pri Raval

The over usage of different man-made chemicals all over the world is now effecting the ozone layer, one of the last defenses of heat

and ultraviolet light.

Effect:

OZONE DEPLETION

Cause:The over usage of different man-made aerosol objects that are being sprayed.Ex: Hair Spray

Effect:Health of all the people in this world will be negatively effected. Not only would the compressed air in the aerosol cans be hurting us but the ozone letting in UV light will wound our skin destructively

The Ozone Layer

• Most people would say that, the ozone is not even needed, that the ozone is only a small useless layer. Sure it’s useless, if you enjoy skin cancer and being burned to death.

• The ozone depletion is also one of the main causes global warming.

• So this problem is not just a problem, it is a problem that causes other problems. It is a chain of problems!

• This isn’t any problem we should take lightly. T• he depleting of this important layer can cause the end of

our world as we know it. • It can burn up the earth and we can also end up like a

burned up deserted barren land.

A little History

• This problem not only has occurred just now. • It is not a problem only caused by us there were also others involved

with it. In fact a couple generations ago, around 1970s people realized this problem and went into action immediately. The all did their part and by the late 1980s the ozone layer was almost completely back to its peak strength.

• But the around the 1990s the ozone started to fade away again. People didn’t believe it at first. They thought the problem was over but instead it started all over again.

• Us remaining stubborn became a unruly and let this problem get out of hand. Now the problem is slowly getting stronger with most of us still not believing the obvious.

• Soon it will rise to its peak and cause world destruction. But if we do start believing this we can start fixing the problem.

The Ozone Layer• The ozone layer does not just evenly disappear throughout the

world; it first gets a hole in it. • The ozone layer is like a plastic bag; it is clear and protects what’s

inside it. • Now if you take a pencil, which would act like ozone depleting

substances, and push it through one area of the bag, if the push is strong enough the bag will rip and have a hole.

• Now if you keep pushing through that hole would widen. • That is how the ozone layer works. • But unlike the plastic bag, the ozone layer can heal and become one

again. • So the ozone layer would do its best to keep those gases on the

inside, but those gases always are pushing the layer farther, to get out. But layer is semi-permeable, meaning it lets some gases out and some gases in.

CFC-11

• A refrigerant is a compound that can change from a liquid to gaseous state and back without requiring extreme changes in conditions. The phase change from gas to liquid results from pressure build up in the coiled portion an appliance, such as a refrigerator or air conditioner.

CFC-12

• Dichlorodifluoromethane, is a colorless gas, and usually sold under the brand name Freon-12, is a chlorofluorocarbon halomethane, used as a refrigerant and aerosol spray propellant

CH3CC13

• (CH3CC13) is very important in the context of global change.

• Global measurements of trichloroethane indicate rising concentrations before and declining concentrations after late 1991

CH3CC13

“This halocarbon is involved in depletion of ozone, and the hydroxyl radical (OH) concentrations determined from its lifetime provide estimates of the lifetimes of most other hydrogen-containing gases involved in the ozone layer and climate.”

-R. G. Prinn From:Atmospheric Trends and Lifetime of ODS

C14

• Carbon-14, a radioactive isotope of carbon, is used to find the age of formerly living things through a process known as radiocarbon dating.

• Though found in all organisms, too much C14 can be dangerous because C14 causes radioactivity and radioactivity has many of the other chemicals in the previous slides so this can cause lots of depleting as well.

C14

“Although carbon-14 decays into nitrogen-14 through beta decay, the amount of carbon-14 in the environment remains constant because new carbon-14 is always being created in the upper atmosphere by cosmic rays.”

- R. G. Prinn From:Atmospheric Trends and Lifetime of ODS

Prevention

There are many solutions to ensure the safety of the layer:• One of the ways we can ensure its safety is by minimizing our

air pollution. As in my previous analogy, air pollution acts like the pencil. But if we minimize our pollution of the air we would at least be able to minimize the force that pencil will apply.

• Another way we could stop the depletion is by reducing the production and usage of ozone depleting chemicals such as CFCs. Stopping the usage of these chemicals will not stop ozone depletion but it will minimize the speed of depletion since these are one of the main substances that greatly affect the destruction of the ozone layer.

Prevention(Continued)

There are also those obvious things we can do, as every says:

• Electronic appliances emit CFC even when they are not in use. So always unplug the electronic instruments when they are not in use.

• Prefer to walk and as far as possible, avoid using vehicles. Simple measures like using public transportation instead of your own private vehicle or carpooling will help in the long run.

• Prefer buying energy-efficient appliances like fluorescent bulbs.• Plant trees, as they absorb UV rays greatly and thus protect the

environment. • Replace your old refrigerators and air conditioners as they are the major

contributors of CFC in the atmosphere. • Avoid or restrict the use of insecticides and pesticides

What scientists predict the ozone hole will become if we start acting upon this cause.

Ethnography

Q) How do you feel about the ozone layer?A) Well I think it is very important and essential

to our survival.

Q) Then how do you feel about it depleting?A) I believe that people are too dumb to realize the importance of this layer. They should do a lot more if they want to survive.

Thank You!

MLA

• Environmental Indicators: Ozone Depletion, U.S. Environmental Protection Agency, Cumulative U.S. Impact on the Ozone Layer, Thursday, August 19, 2010

• Atmospheric Trends and Lifetime of ODS and• Global OH Concentrations• R. G. Prinn, R. F. Weiss, B. R. Miller, J. Huang, F. N. Alyea, D. M.

Cunnold,• P. J. Fraser, D. E. Hartley, P. G. Simmonds• Johnston, H. S., D. Kattenhorn, and G. Whitten (1976), Use of

excess carbon 14 data to calibrate models of stratospheric ozone depletion by supersonic transports, J. Geophys. Res., 81(3), 368–380, doi:10.1029/JC081i003p00368.