The ozone is a major component of the atmosphere that helps protect the Earth and keep the Earth within relatively stable conditions. As stratospheric ozone depletion occurs it poses several serious risk factors for Earth and society as a whole. While ozone depletion is still being studied every day by leading experts around the world there are many things that have already been discovered.
What Is Stratospheric Ozone Depletion?
Stratospheric ozone depletion occurs when chemical reactions take place within the atmosphere. The chemical reactions that cause this ozone depletion often take place in stratospheric clouds during the winter stratosphere. The molecules that are often involved in these chemical reactions include chlorine, bromine, fluorine, iodine, carbon, nitrogen, hydrogen, and oxygen. All of these chemicals do not need to be present during each chemical reaction, but at least two do. When these chemicals react in certain ways they can directly lead to ozone depletion.
To better understand how these chemical reactions affect the stratosphere experts have used laboratory findings, observations of the atmosphere, and computer technology to help model the past, current and future atmospheric conditions. These innovative ideas have all helped experts to understand how, where and why these chemical reactions occur. They are able to model the exact makeup of the atmosphere and the current conditions. For example, the computer models and diagrams can account for temperature, wind speed and direction, chemical makeup, and sunlight. They can directly understand how these factors impact the chemical reactions and how together they affect the ozone depletion.
Experts have found that chlorine and bromine are the two main chemicals that have the largest impact on stratospheric ozone depletion. These two chemicals react to each other in catalytic cycles. This means that when they react just one time they can cause thousands of ozone molecules to get destroyed, thus depleting the ozone. Computer models are being used daily to better understand how and why this happens.
Using Atmospheric Observations
Another main way that scientists are studying ozone depletion is through atmospheric observations. Scientists are able to study the atmosphere using satellites, balloons, and aircraft to monitor the ozone for its current conditions and depletion. These observations are giving us accurate measures of all pertinent information to help society better understand how stratospheric ozone depletion occurs.
Through these atmospheric observations, experts are studying the current gas levels that are present within the ozone and determining how their abundances change over the course of a day, month or season. These atmospheric observations have shown experts that halogen gases are required to cause ozone depletion. The instruments already mentioned help to monitor the gas levels and check for ozone depletion.
Process of Ozone Depletion
Ozone depletion is a very difficult concept to understand because there are many aspects that go into it. To help better understand the process of ozone depletion it is crucial to understand how the chemicals get into the atmosphere, to begin with. Upward moving air currents around the tropics carry up many chemicals, like methane, chlorofluorocarbons, nitrous oxide, and water, into the stratosphere. They are carried into the atmosphere and resemble topical cumulus clouds. When these clouds reach the atmosphere the molecules inside of these compounds are broken down by their exposure to ultraviolet radiation that is given off from the sun. When these chemicals break down they release free radicals that break down the ozone layer. Some of the free radicals have been noticed to be nitrogen dioxide and chlorine monoxide. These are unstable elements that bind to other atoms in the ozone and deplete them.
Another way that chemicals are released into the atmosphere is through volcanoes and aircraft. These chemicals do not need to be brought to the atmosphere from winds because they are already present within the clouds themselves. Since the stratospheric ozone layer helps protect all of Earth and society from the ultraviolet radiation given off from the sun it is crucial that we all do our part to help protect the environment that we live in.
Effect of Temperature on Ozone Depletion
One of the greatest factors that affect ozone depletion is the temperature of the air. In the coldest places on earth, above the arctic and Antarctica, the average monthly temperatures have been recorded. Minimum temperatures in these areas can reach about negative eighty degrees Celsius to negative ninety degrees Celsius. When the air temperature reaches these low points polar stratospheric clouds are able to form. When these clouds form the chemical reactions that occur can cause ozone depletion. These clouds tend to form over the Arctic areas about one to two months out of the year. They tend to form over Antarctica for about five to six months in a given year.
When these clouds form chlorine gas, or CIO, is able to form. This is a highly reactive compound that binds to other molecules in the atmosphere and drastically helps deplete the ozone. These chemical reactions occur for many months out of the year in both areas, but they will not occur if the temperature reaches these extremely low values. If the temperature is hotter than expected the number of chemical reactions is lowered and the ozone does not deplete nearly as fast.
CFCs In The Ozone
Chlorofluorocarbons, or CFCs, are a major issue of debate around the world. They are a known compound that impacts ozone depletion. CFCs are made up of chlorine, fluorine and carbon atoms. When these CFCs are released into the atmosphere and brought up to the stratosphere by strong winds the ultraviolet radiation from the sun hits the CFC molecule. This causes a chlorine atom to break apart from the chlorine molecule. When the chlorine atom breaks apart it travels freely around the atmosphere trying to find a partner to bond with. It often meets with ozone molecules, or oxygen atoms, and steals oxygen atoms from others. This causes a chain reaction and causes chlorine atoms to steal ozone atoms for a very long time. Before this process is over, the chlorine atom has likely depleted and destroyed thousands of oxygen atoms. Computer models from experts in the field analyze that a single CFC molecule is able to destroy up to about one hundred thousand ozone molecules.
Chlorine Catalytic Cycle
When chlorine is free in the atmosphere it takes place in many catalytic cycles. This cycle is able to continually repeat itself thousands of times before the atoms are able to deplete enough of the ozone and die out. The catalytic cycle can start with either a CIO molecule or a CI molecule. Basically, when a CIO or CI molecule is free in the atmosphere it binds with other O atoms. They steal an O atom and then release it later in the process. When the O is released it allows the molecule to once again become a CIO or a CI molecule. No matter what molecule it becomes, it is free to steal oxygen atoms from the atmosphere and break up the ozone layer.
The stratospheric ozone depletion is a difficult concept to understand but is one that is being studied each and every day by leading scientists and experts in the field. They are continually looking for new ways to understand the process and stop it from occurring to help better the planet as a whole.