1. Page 1 By: Alvaro Reyes Sheirler Ojasmar Sheirler Ojasmar Kevin Banegas Kevin Banegas

2. Page 2 Ozone is a gas that occurs naturally in our atmosphere. Ozone is a gas that occurs naturally in our atmosphere. The ozone layer is a deep layer in the stratosphere, encircling the Earth, that has large amounts of ozone in it. The ozone layer is a deep layer in the stratosphere, encircling the Earth, that has large amounts of ozone in it. The stratosphere is the second major atmospheric layer above the troposphere, extending in altitude from about 8 to 30 miles high. The stratosphere is the second major atmospheric layer above the troposphere, extending in altitude from about 8 to 30 miles high. The troposphere is the lowest major atmospheric layer, extending from the Earth's surface up to the bottom of the stratosphere. The troposphere is the lowest major atmospheric layer, extending from the Earth's surface up to the bottom of the stratosphere.

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4. Page 4 ozone layerThe ozone layer in the stratosphere is produced through a process known as ‘photodissociation’ in which oxygen (O2) filtering up from the top of the troposphere is transformed, under the influence of sunlight, to ozone (O3). ozoneAlthough ozone is produced (and destroyed) at all altitudes, the process of dissociation of oxygen is greatest above the equator and the tropics, simply because that is where solar radiation is strongest.

5. Page 5 ozoneThere are also processes that destroy ozone, preventing the overall loss of oxygen and build up of ozone in the atmosphere over time. Under the influence of ultraviolet radiation some ozone molecules photodissociate and break apart into ‘ordinary’ oxygen (O2) and a single oxygen atom (O). ozone ozoneHuman activities are now interfering with the balance of these reactions by increasing the rate of ozone destruction, while the rate of stratospheric production remains the same. The result is a progressive and significant decline in the concentration of stratospheric ozone.

6. Page 6 Ozone is a triatomic form of oxygen (O3), found in the Earth's atmosphere. A combination of low temperatures, elevated chlorine and bromine concentrations in the upper stratosphere are responsible for the destruction of ozone. include hydrochlorofluorocarbons (HCFCs), and volatile organic compounds (VOCs). Other ozone depletion substances (ODS), include hydrochlorofluorocarbons (HCFCs), and volatile organic compounds (VOCs).

7. Page 7 This free chlorine atom reacts with an ozone molecule (O3), and forms chlorine monoxide (ClO), and a molecule of oxygen. Now, ClO reacts with an ozone molecule to form a chlorine atom, and two molecules of oxygen. The free chlorine molecule again reacts with ozone to form chlorine monoxide. The process continues, and this results in the depletion of the ozone layer..

8. Page 8 'hole' ultraviolet rays Ultraviolet rays As ozone depletes in the stratosphere, it forms a 'hole' in the layer. This hole enables harmful ultraviolet rays to enter the Earth's atmosphere. Ultraviolet rays of the Sun are associated with a number of health related, and environmental issues.

9. Page 9 Impact on Humans Skin cancer:Skin cancer: Exposure to ultraviolet rays poses an increased risk of developing several types of skin cancers, including malignant melanoma, basal and squamous cell carcinoma. Eye damage:Eye damage: Direct exposure to UV radiations can result in photokeratitis (snow blindness), and cataracts. Immune system damage:Immune system damage: Effects of UV rays include impairment of the immune system. Increased exposure to UV rays weakens the response of the immune system. Accelerated aging of skin:Accelerated aging of skin: Constant exposure to UV radiation can cause photo allergy, which results in the outbreak of rash in fair- skinned people. Other effects: irritation,Other effects: Ozone chemicals can cause difficulty in breathing, chest pain, throat irritation, and hamper lung functioning.

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