Ozone Depletion and Largest Ozone Hole Essay examples

Submitted By Miker1284
Words: 1993
Pages: 8
Open Document
Introduction The Montreal Protocol stopped the continual usage of CFCs in everyday appliances which include refrigerators and in aerosol cans. CFCs, an abbreviation for chlorofluorocarbons were designed in the 1930s, originally made to be incorporated into everyday life for its nontoxic, nonflammable and unreactive properties which were thought of as “wonder chemicals”. These chemicals were assumed to be safe and unknown that ozone depletion was a result of CFC use as refrigerants and in aerosol cans. Adopted on the 16th September 1987, the Montreal protocol was created by the United Nations Environment Programme aimed at regulating the depletion of the Earth’s ozone layer. Since the agreement has been adopted, amendments have been created to completely phase out the use of CFCs and halons, as well as the production and use of other substances including carbon tetrafluoride (CF4), trichloroethane (C2HCl3) and hydrofluorocarbons (HFCs). Currently, the treaty has close to 200 signatories.
Ozone Depletion Ozone (O3) is a triatomic molecule responsible for absorbing UV radiation in the stratosphere. It is produced by the breaking of chemical bonds in an oxygen molecule (O2) in a process known as photodissociation producing two single oxygen atoms which bind to oxygen molecules to form Ozone. Ozone buildup in the stratosphere was a result in increases in atmospheric oxygen concentrations two billion years ago in the Precambrian era where oxygen levels increased to between 5-18% at atmospheric level . There are four regions of UV radiation however, based on UV radiation interaction with biological matters, there are three sections of UV radiation, UV A (315-400nm), UV B (280-315nm) and UV C (100-280nm). UV radiation has little penetrating power and hence is usually linked to skin cancer (both melanoma and carcinoma). Suntans are the body’s natural defenses against UV radiation, melanin pigments in cells are activated and migrate to the surface of the skin, giving a darker complexion. Ozone screens UV B radiation and prevents penetration onto the Earth’s crust, preventing loss of marine life and skin cancer. This is done by absorbing UV B radiation by one of the Ozone’s Oxygen-Oxygen bonds, breaking it down to an oxygen molecule (O2) and an oxygen atom (O). The oxygen molecule then reacts with the oxygen atom reforming ozone molecules.
The theory of ozone depletion began with Dutch chemist, Paul Crutzen who published a paper suggesting that nitrogen oxide reduced the rate of ozone production. His theory believed that Nitrogen Oxide (NO) reacted free oxygen atoms in the atmosphere forming nitrogen dioxide (NO2).
Dr F. Sherwood Rowland and Dr Manuel E. Molina recognized the possibility for CFCs to become a major source of chlorine which could potentially break down ozone molecules in the stratosphere through UV radiation forming chlorine radicals. Chlorine radicals (Cl•) broke down ozone (O3) by taking an oxygen atom from ozone molecules forming chlorine monoxide (ClO). The chlorine monoxide then reacts with an oxygen atom to form an oxygen molecule and a chlorine atom, hence, the free chlorine radical is a catalyst itself. (fig.1.1) Rowland and Molina’s work was validated by the British Antarctic Survey in 1985 by the discovery of a hole in the ozone layer located in the polar region of Earth.
Fig.1.1

This process of ozone depletion can repeat itself over again and again, resulting thousands of ozone molecules converted into oxygen molecules by a single free radical. Over time, the continual usage of CFCs resulted in extensive damage in the ozone later creating holes, allowing lethal dosages of UV B radiation penetrating onto the earth’s surface, capable of destroying large amounts of marine plankton life up to 30 meters below sea level. The largest ozone hole is located in the polar regions of the Earth, especially in Antarctica (fig1.2), where a decline in marine life has occurred due to UV B radiation
Show More

Related Documents: Ozone Depletion and Largest Ozone Hole Essay examples

Ozone Depletion Research Paper

Ozone depletion describes two distinct but related phenomena observed since the late 1970s: a steady decline of about 4% per decade in the total volume of ozone in Earth's stratosphere, and a much larger springtime decrease in stratospheric ozone over Earth's polar regions. The latter phenomenon is referred to as the ozone hole. In addition to these well-known stratospheric phenomena, there are also springtime polar tropospheric ozone depletion events. The details of polar ozone hole formation differ…

Words 7273 - Pages 30

Essay On Chemical Monitoring And Management

Year 12 Chemistry ASSESSMENT TASK 3 Chemical Monitoring and Management INTRODUCTION Component: This task incorporates the 3 assessment components. Knowledge and understanding of: the practice of chemistry, applications and uses of chemistry and their implications for society and the environment, and current issues, research and development in chemistry bonding, energy, chemical reactions, carbon chemistry and stoichiometry Skills in: planning and conducting first-hand investigations gathering…

Words 2638 - Pages 11

What Is Population Bomb

Explain what is meant by “The Population Bomb” and to what extent do you agree that this bomb has been diffused. “Population will inevitably and completely outstrip whatever small increases in food supplies we make. The death rate will increase until at least 100-200 million people per year will be starving to death during the next ten years.”- Paul Ehrlich, Stanford University biologist The population bomb theory was made popular by Paul Ehrlich's 1968 book “The Population Bomb”, Ehrlich posited…

Words 2000 - Pages 8

Essay on Pollution: Pollution and Drilling Noise Pollution

could be damaging to health and the environment and occurs as a result of poor environmental management, waste disposal practices and accidental spills of toxic waste in industrial and commercial activities such as open cast mining, where enormous holes are dug in the ground and have the propensity to discharge a variety of chemicals and lubricating oils that are left unattended too or not properly disposed of will lead to increased land pollution. This pollution includes biodegradable, combustible…

Words 2302 - Pages 10

Effects Of Natural Disasters

the world are affected by natural disasters. These may be caused by climate change such as drought, flood, and cyclone, the environment such as pollution, deforestation, desertification, pest infestation or combinations of these, or the destroy of ozone layer will contribute to the green house effect. People's homes are wiped out and livelihoods are destroyed. Poverty, population pressures and environmental degradation mean that increasing numbers of people are vulnerable to natural disasters. In…

Words 4729 - Pages 19

Research Paper On Atoms

Atoms are made of protons, electrons, and neutrons. Protons and neutrons are located inside the nucleus that is at the center of an atom. Electrons occupy orbitals, which are located outside the nucleus. In this module, you will study the structure of atoms. Atoms are the building blocks of matter. Every living and non-living thing is made of atoms. Those same atoms make up elements. For example, gold is an element and is made of gold atoms. Atoms are the basic building blocks of matter that make…

Words 5848 - Pages 24

climate change Essay

climate change is an issue that is affecting people all over the world. Climate change From Wikipedia, the free encyclopedia For current and future climatological effects of human influences, see global warming. For the study of past climate change, see paleoclimatology. For temperatures on the longest time scales, see geologic temperature record. Page semi-protected Atmospheric sciences ShipTracks MODIS 2005may11.jpg Atmospheric physics Atmospheric dynamics (category) Atmospheric chemistry…

Words 7672 - Pages 31

Module Quizzes Essay

Module 1: Syllabus How long do you have to take an E-test? 2 hours Which of the following is curved? E-tests and the E-final Final Grades have? Pluses and minuses If a positive feedback signals reaches the comparator, what occurs? Comparator will turn on the controlled Where should you go to find updates on the course? Announcements in Bioespresso Where should you go to access your readings and assignments? www.bioespresso.com Where do you submit your extra credit paper? Dr…

Words 14237 - Pages 57