What is Global Warming?
Global Warming is the increase of Earth's average surface temperature due to effect of greenhouse gases, such as carbon dioxide emissions from burning fossil fuels or from deforestation, which trap heat that would otherwise escape from Earth. This is a type of greenhouse effect.
For the past few decades, scientists have observed that the cause of global warming has been due to the increase of greenhouse gases into the atmosphere.
The higher the concentration of these greenhouse gases like carbon dioxide, methane, ozone in the atmosphere, the more heat is reflected back to the earth.
As the concentration of greenhouse gases grows, more heat is trapped in the atmosphere and less escapes back into space. This increase in trapped heat changes the climate and alters weather patterns, which may hasten species extinction, influence the length of seasons, cause coastal flooding, and lead to more frequent and severe storms.
It also cause polar ice caps melting
The ice caps melting is a four-pronged danger.
First, it will raise sea levels. There are 5,773,000 cubic miles of water in ice caps, glaciers, and permanent snow. According to the National Snow and Ice Data Center, if all glaciers melted today the seas would rise about 230 feet. Luckily, that’s not going to happen all in one go! But sea levels will rise.
Second, melting ice caps will throw the global ecosystem out of balance. The ice caps are fresh water, and when they melt they will desalinate the ocean, or in plain English - make it less salty. The desalinization of the gulf current will "screw up" ocean currents, which regulate temperatures. The stream shutdown or irregularity would cool the area around north-east America and Western Europe. Luckily, that will slow some of the other effects of global warming in that area!
Third, temperature rises and changing landscapes in the artic circle will endanger several species of animals. Only the most adaptable will survive.
Fourth, global warming could snowball with the ice caps gone. Ice caps are white, and reflect sunlight, much of which is relected back into space, further cooling Earth. If the ice caps melt, the only reflector is the ocean. Darker colors absorb sunlight, further warming the Earth.
Human Activities and Greenhouse Gases
Human activities also add significantly to the level of naturally occurring greenhouse gases:
- Carbon dioxide is released into the atmosphere by the burning of solid waste, wood and wood products, and fossil fuels (oil, natural gas, and coal).
- Nitrous oxide emissions occur during various agricultural and industrial processes, and when solid waste or fossil fuels are burned.
- Methane is emitted when organic waste decomposes, whether in landfills or in connection with livestock farming. Methane emissions also occur during the production and transport of fossil fuels.
How to stop global warming?
There are the some easy ways to prevent global warming. Everyone can do it!
1) Turn off lights when they are not in use. Although the light bulb itself does not emit gases, the power plants that are powering it.
2) Whenever possible, use a fan instead of air conditioning.
3) Keep a car tuned up. When it is running properly, it emits fewer harmful gases.
4) Walk or ride a bike when it's possible.
5) Recycle. Un-recycled garbage ends up in a landfill, which produces methane. In addition, recycled goods require less energy to produce than products made from scratch.
6) Plant trees and other plant life whenever possible. Plants take carbon dioxide out of the air and release oxygen.
7) Don't burn garbage. This releases carbon dioxide and hydrocarbons into the atmosphere.
We can use the poster, flyers and give seminar talks to educate the people.
We also can hold some school activity about global warming.
Source :http://www.nmsea.org/Curriculum/Primer/Global_Warming/fossil_fuels_and_global_warming.htm
http://www.sirusti.com/surya/eco/globalwarmingintro.html
Article is for reference only.
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