Global Warming, Causes of Global Warming, Effects of Global Warming

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Global Warming

A gradual increase in the overall temperature of the earth’s atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants

Causes of Global Warming

  • The main causes of global warming, in order of the magnitude of their impact, are:

  • Carbon Dioxide from:

    • Fossil Fuel

    • Deforestation

    • Failing Sinks

  • Methane from:

    • Cattle and Rice Paddies

    • the Arctic Tundra

    • Clathrates

  • Nitrogen Oxides from Farming

  • Other Gases

Effects of Global Warming

When it comes to global warming, harmful effects like melting polar ice caps, weather changes, and an increase in diseases are changing the world and will ultimately affect your life. Below is the list of effects that global warming is having on environment, climate and human kind.

Melting of Glaciers

  • The melting of glaciers will create plethora of problems for human kind and the animals living in the earth. Due to increased global warming, the level of the sea will rise which will lead to flooding and this will in turn create havoc in human life.

  • Apart from raising the sea levels, it will also endanger several species of animals and thus will hamper the balance of the ecosystem. Moreover these large glaciers reflect light back into the space and with meltdown of these glaciers, earth will be further warmed.

Climate Change

  • Irregular weather patterns have already started showing results. Increased precipitation in the form of rain has already been noticed in polar and sub Polar Regions.

  • More global warming will lead to more evaporation which will cause more rains. Animals and plants cannot easily adapt to increase rainfall. Plants may die due to it and animals may migrate to other areas, which can cause entire ecosystem out of balance.

  • Droughts: Large scale evaporation will be the major cause of droughts in many places particularly Africa. Although, it is reeling under the huge pressure of water crisis, increased global warming would further make the situation worse and will cause malnutrition.

  • Diseases: As the temperature becomes warmer, it will have an effect on the health of humans and the diseases they are exposed to. With the increase in the rainfall, water borne diseases are likely to spread specially malaria. The earth will become warmer and as a result heat waves are likely to increase that will cause a major blow to the people particularly in Europe.

  • Hurricanes frequency: As the temperature of the oceans rises, hurricanes and other storms are likely to become stronger. With the increase in the global warming the water in the ocean warms up and it heats up the surrounding air, creating hurricanes. More water evaporation means more hurricanes.

  • Agriculture: Global warming will affect agriculture. Although the results are not visible yet, but it may show its colours in years to come. As the global temperature will increase plants will find it harder to survive and will die. Plants are the major source of food for human beings and as a result food shortage will occur. The shortage of the food may lead to war and conflicts in some countries.

Steps to Control Global Warming

  • Use Public Transport

  • Use Renewable Energy Like Wind Power

  • Burn Methane

  • Use Smart Cooler, Heater & Air Conditioner

  • Tune up and maintain vehicles properly

  • Reduce electricity usage to the maximum

  • Prefer recycling.

Ozone Depletion

  • Ozone: Ozone is a highly reactive and unstable gas, which is formed by the recombination of oxygen () atoms in the presence of intense radiation. Its symbol is .

  • Ozone Layer: The ozone layer is a naturally occurring zone found in the stratosphere, situated between 1015 kms above the surface of the Earth. The main function of the ozone layer is to act as a shield against ultraviolet (UV) radiations from the Sun because these rays are harmful to life.

  • Ozone Depletion: Destruction of the stratospheric ozone layer which shields the earth from ultraviolet radiation harmful to life. ...

  • Causes Of Ozone Layer Depletion: The Main Ozone-Depleting Substances (ODS)

  • Chlorofluorocarbons (CFCs)

  • The most widely used ODS, accounting for over 80% of total stratospheric ozone depletion.

  • Used as coolants in refrigerators, freezers and air conditioners in buildings and cars manufactured before 1995.

  • Found in industrial solvents, dry-cleaning agents and hospital sterilants.

  • Also used in foam products — such as soft-foam padding (e.g. cushions and mattresses) and rigid foam (e.g. home insulation).

  • Halons

  • Used in some fire extinguishers, in cases where materials and equipment would be destroyed by water or other fire extinguisher chemicals. In B.C., halons cause greater damage to the ozone layer than do CFCs from automobile air conditioners.

Methyl Chloroform

  • Used mainly in industry — for vapour degreasing, some aerosols, cold cleaning, adhesives and chemical processing.

  • Carbon Tetrachloride

  • Used in solvents and some fire extinguishers.

  • Hydro fluorocarbons (HCFCs)

  • HCFCs have become major, ―transitional‖ substitutes for CFCs. They are much less harmful to stratospheric ozone than CFCs are. But HCFCs they still cause some ozone destruction and are potent greenhouse gases.

OR

  • The cause of ozone depletion is the increase in the level of free radicals such as hydroxyl radicals, nitric oxide radicals and atomic chlorine and bromine. The most important compound, which accounts for almost 80% of the total depletion of ozone in the stratosphere are chlorofluorocarbons (CFC).

  • These compounds are very stable in the lower atmosphere of the Earth, but in the stratosphere, they break down to release a free chlorine atom due to ultraviolet radiation. A free chlorine atom reacts with an ozone molecule () and forms chlorine monoxide (ClO) and a molecule of oxygen. Now chlorine monoxide 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 the result is the reduction or depletion of ozone in the stratosphere.

Effects of Ozone Depletion

Following are the major effects of ozone layer depletion.

  • It will increase the risk of skin cancer

  • It has resulted in melanomas, a kind of tumour.

  • It greatly affects eyes and produces disease of vision.

  • It suppresses immunity system of human beings.

  • UV rays damage various crops.

  • It kills plankton and fish larvae.

  • It causes sunburn in human beings.

  • It causes spotting of leaves in plants and trees, thus decreases productivity of the plants.

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