Global Warming
More Definition about Global Warming:
- increase in the average temperature of the earth’s surface.
- the expected consequence of an increase in the concentration of greenhouse gases by human activity
- eating that occurs when carbon dioxide traps the Sun’s heat near Earth’s surface, causing Earth’s temperature to rise
- An increase in the average temperature of the earth’s atmosphere, especially a sustained increase sufficient to cause climatic change. Most scientists believe that a rise in carbon dioxide levels (caused by automobile, power plant, and other emissions) will lead to further global warming.
- the apparent recent trend of increasing world-surface and tropospheric temperatures, thought to be caused by pollutants, and their “entrapment” of heat. This phenomenon is popularly known as “the greenhouse effect.”
- Global warming refers generally to the rise in the average temperature of the Earth’s atmosphere (specifically the air closest to the surface, where we live) and oceans in the past century or so. The concept also insinuates that this trend will continue unless fairly large steps are taken to mitigate our greenhouse gas emissions – the major force behind the warming.
Global Warming is caused by many things
The causes are split up into two groups, man-made or anthropogenic causes, and natural causes.
- Natural Causes:
While the natural causes are rather few and far between, and indeed actually tend to balance out in the grand scheme of things, we can’t have a balanced page here without discussing some of the natural factors that contribute to global warming. One natural cause of global warming is the natural phenomenon of solar variation.
Solar variation is any kind of change in the amount of radiant energy given off by the Sun. This variation is usually very small however, and scientific results suggest that it has only changed by about 0.1% in the past 2000 years. While this may have been a small contributing factor in the current trend towards global warming, it is not something we can do anything about right now, and it’s also not the most significant cause by any means.
Another natural cause of global climate change is the eruption of volcanoes here on Earth. This, combined with solar variation has likely caused some of the changes in weather and climate that have been taking place in the past 100 years or so, and are expected to continue and worsen if steps are not taken to remedy our situation. Volcanoes contribute in that they release harmful gases and carbon dioxide into the atmosphere when they erupt. For years, they have been a natural contributor to acid rain. Volcanoes also release aerosols like those released from hairspray bottles, which are also damaging to the atmosphere. Large volcanic eruptions actually usually end up having a cooling effect on the climate, however, and are therefore generally a balancing force of nature and not a major cause of global warming.
- Man-made Causes
Man-made causes probably do the most damage. There are many man-made causes. Pollution is one of the biggest man-made problems. Pollution comes in many shapes and sizes. Burning fossil fuels is one thing that causes pollution. Fossil fuels are fuels made of organic matter such as coal, or oil. When fossil fuels are burned they give off a green house gas called CO2. Also mining coal and oil allows methane to escape. How does it escape? Methane is naturally in the ground. When coal or oil is mined you have to dig up the earth a little. When you dig up the fossil fuels you dig up the methane as well.
Another major man-made cause of Global Warming is population. More people means more food, and more methods of transportation, right? That means more methane because there will be more burning of fossil fuels, and more agriculture. Now your probably thinking, “Wait a minute, you said agriculture is going to be damaged by Global Warming, but now you’re saying agriculture is going to help cause Global Warming?” Well, have you ever been in a barn filled with animals and you smell something terrible? You’re smelling methane. Another source of methane is manure. Because more food is needed we have to raise food. Animals like cows are a source of food which means more manure and methane. Another problem with the increasing population is transportation. More people means more cars, and more cars means more pollution. Also, many people have more than one car.
Since CO2 contributes to global warming, the increase in population makes the problem worse because we breathe out CO2. Also, the trees that convert our CO2 to oxygen are being demolished because we’re using the land that we cut the trees down from as property for our homes and buildings. We are not replacing the trees (an important part of our eco system), so we are constantly taking advantage of our natural resources and giving nothing back in return.
Greenhouse Effect
the warming effect due to radiated energy; refers to the predicted warming of the Earth’s surface through increases in the atmospheric concentration of several gases, particularly carbon dioxide, due primarily to the combustion of fossil fuels; the greenhouse effect is predicted to have major effects on the world’s pattern of climate, serious implications for agriculture and cause polar ice caps to melt, subsequently causing rises in sea levels.
Greenhouse effect – the effect produced as certain atmospheric gases allow incoming solar radiation to pass through to Earth’s surface, but prevent the outgoing (infrared) radiation, which is re-radiated from Earth, from escaping into outer space. The effect is responsible for warming the planet.
Greenhouse Gases
atmospheric gases which enhance the natural greenhouse effect, including carbon dioxide, methane, chlorofluorocarbons (CFCs), nitrous oxide, ozone and water vapour; atmospheric gases which prevent the escape of solar radiation radiated from the Earth’s surface.
Greenhouse gas – any gas that absorbs infrared radiation in the atmosphere.
Where does greenhouse gas pollution come from?
- Burning of fossil fuels
Most of Australia’s greenhouse gas emissions come from the burning of fossil fuels for energy (eg. for electricity and transport). When oil, gas or coal burns, carbon contained within it combines with oxygen in the air to create carbon dioxide.
- Deforestation: burning and removing vegetation
Plants take up carbon dioxide from the air during photosynthesis and are therefore often referred to as carbon ’sinks’. When land is cleared and vegetation removed or burnt, the stored carbon is converted back to carbon dioxide.
Since 1788, we have cleared 20 billion trees and significantly modified more than 70% of Australia’s native vegetation.
- Farming
Animals, particularly sheep and cattle, produce large amounts of methane. Some fertilisers also release nitrous oxide, which is another greenhouse gas.
- Waste breakdown
Carbon dioxide and methane is released during the decay of food, vegetation and paper dumped in landfills. The same thing occurs when sewage wastes break down.
- Industry
Many industrial processes such as cement and liquid natural gas production and coal mining produce or emit a variety of greenhouse gases.
