The term global warming is often used synonymously with the term climate change but the two terms have distinct meanings. Global warming is the combined result of anthropogenic (human – caused) emissions of green house gases and changes in solar irradiance,
while climate changes refers to any change in the state of climate that can be identified by changes in the average and/or the variability of its properties (e.g. temperature, precipitation) and hat persists for an extended period, typically decades or longer.
Read also: Effects Of Global Warming On Man And His Environment, And The Ecosystem
Global warming is the increase of Earth’s average surface temperature due to effect of green house gases, such as carbon dioxide emissions from burning fossil fuels or from deforestation which trap heat that would other wise escape from Earth. This is a type of green house effect.
CAUSES OF GLOBAL WARMING
Green house gases are released into the atmosphere in many ways, including through the burning of fossil. Fuels (such as coal and petroleum) and by deforestation. As some environments warm (eg. The Arctic tundra) they also release carbon that may have been stored for thousands of years.
1. Burning Fossil Fuels: Most of Australia’s green house 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. Australia’s electricity-related emissions are high because they rely primarily (77%) of coal for electricity generation and coal is the most green house-intensive fuel.
2. Deforestation (Burning and Removing Vegetation): All plants take in carbon dioxide from the air and release oxygen, which is why they are sometimes referred to as carbon “sinks”. This process is called photosynthesis. When land is cleared and trees or vegetation removed or burnt, the stored carbon is converted back into carbon dioxide. Before European settlement in 1788, forest and woodlands covered 54% of Australia. This has now been reduced to 42% mainly through land clearing.
3. Farming: Animals, particularly sheep and cattle, produce large amounts of methane. Some fertilizers also release nitrous oxide which is another green house gas.
4. Waste Breakdown: Carbon dioxide and methane are released during the decay of food, vegetation and paper dumped I landfills. The same thing occurs when sewage wastes break down.
5. Industry: Many industrial processes such as cement production, liquid natural gas production and coal mining, produce or emit a variety of greenhouse gases.