• Global warming CFCs and other ODSs seem likely to increase the rate of greenhouse warming by absorbing heat 10,000 times more than carbon dioxide and when ODSs destroy the ozone layer, more various radiations are then able to reach the earth. This increases the temperature on the earth's surface, but decrease the temperature at the upper atmosphere. This phenomenon produces more clouds in the stratosphere and diminishes more ozone concentration. The higher the earth's temperature is, the more the ocean expands and then the more areas are flooded such as in the lower areas of Bangladesh or some islands. Also, the icebergs in both north and south poles will melt down, and increase the height of sea level. The Earth's atmosphere will consequently change vigorously, affecting all people in the world. • Immune system and vaccination Ultraviolet radiation has an allergic reaction to skin and affects the immune system, in particular in skin cells which is the first protector of human body to fight against diseases. To have a vaccination, cells in the skin have an immunization to response antigens by stimulating the creation of white blood cells which defend the body against foreign substances. Exposure to UV radiation can suppress the induction of some immune responses. This may cause the development of skin cancer, other skin ailments such as Measles, Chickenpox, Herpes simplex and other disease infections such as Tuberculosis, Leprosy, Candidiasis and Malaria. • Skin cancer UV-B radiation which suppresses the human immune system burns human skin, making it thicker, browner and eventually be a skin cancer if taking intense exposure. The US Environmental Protection Agency (US-EPA) has estimated that a 1% reduction of stratospheric ozone results a 2% increase of people who have the cutaneous malignant melanoma in developing countries and 0.2-3% of these people will die of this sickness. • Damage to eyes A corneal ulcer can occur form this radiation. When the eye exposes to UV-B, it will develop the photoketitis or snow blindness eyelids and the skin around the eye will turn to brown. The eye will eventually be a cataract, if still keeping exposure to this radiation. • Impact on ocean A loss of stratospheric ozone adversely affects oceanic organisms, i.e. Planktons, and marine food webs. Planktons contain photosynthetic organisms that absorb carbon dioxide and produce, in each year, over one and a half of all biomass in the world, or approximately 6 x 10 4 kilograms. UV-B has a substantial effect on the populations of plankton. If plankton populations decline, it may lead to increased carbon dioxide levels. A 10% reduction of absorbed carbon dioxide in the ocean means a large amount of carbon dioxide remaining in the atmosphere and thus the increase of global temperature. A 25% loss of stratospheric ozone equals a 10-35% reduction of biomass produced by planktons (depending on the level of sea where planktons inhabit). The zooplanktons which consume planktons and are food of most marine economic animals are also affected. The 15 % decrease of ozone level at the surface of water can cause these zooplanktons to death within 5 days and eventually has an impact to the economy. • Impact on land plants A high increase in UV radiation may disrupt many ecosystems on land. Rice products may be drastically reduced by the effects of UV-B on the nitrogen assimilating activities of micro-organisms. With a diminishing ozone layer, it is likely that the supply of natural nitrogen to ecosystems, such as tropical rice paddies, will be significantly reduced. Most plants (and trees) grow more slowly and become smaller and more stunted as adult plants when exposed to large amounts of UV-B. Increased UV-B inhibits pollen germination and reduces quality of agricultural food. • Increased effects of air pollution When ozone level in stratospheric ozone decreases, the UV-B can reach to the to tropospheric layer and cause many harmful chemical reactions such as the reaction with the exhaust gas released by automobiles and smoke released from industrial factories. These result in the creation of ozone at the Earth's surface level, which is the toxic gas for human beings and plants. This gas will not drift up to the stratospheric layer and although it can absorb Ultraviolet radiation like stratospheric ozone, it can't replace the destroyed ozone. • Damage to materials UV-radiation causes many materials to degrade more rapidly. Plastic materials used outdoors will have much shorter lifetimes with small increases of UV radiation. PVC sidings, window and door frames, pipes, gutters, etc. used in buildings degrade faster. The level of destruction can be higher for materials which are located in high temperature and strong light areas especially in tropical countries.
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Impacts of ozone depletion