Global warming is one of the ?hottest? issues nowadays. The current climate change is the worst yet to happen. Global warming is an overall increase in world temperature which is attributed to the increasing number of greenhouse gases trapped in the atmosphere. Searching an alternative energy source is considered a way of reducing the toxic emissions.

Greenhouse gases can be produced both by natural and industrial processes. The most abundant greenhouse gases on earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, ozone and CFCs.

There are several sources of greenhouse gases. Burning of fossil fuels and deforestation lead to higher concentration of carbon dioxide in our atmosphere. Without the trees and plants to take in the carbon dioxide emitted by burning fossil fuels, natural gas and petroleum products, all of the CO2 emitted stays in the atmosphere.

Also the use of CFCs or chlorofluorocarbons in refrigeration systems and in fire suppression systems and other manufacturing processes also increase the greenhouse content of our atmosphere. While the use of non-organic fertilizers in agriculture also lead to higher nitrous oxide concentrations, another greenhouse gas.

In the United States, greenhouse gas emissions mainly come from the use of fossil fuels as energy source. Approximately 82 percent of the greenhouse gas emission in the United States in 2006 came from the combustion of coal, natural gas and petroleum (United States Energy Information Administration). Meanwhile in Asia, Chine is expected to increase its emission of greenhouse gas because of the construction of old-fashioned power plants in its internal provinces. Currently, the carbon dioxide concentrations in the atmosphere are the highest in 150,000 years. The 1990s was most likely the warmest decade in history, while 1998 was the warmest year (Greenpeace).

Not controlling the greenhouse gas being emitted by human activity can increase climate change the next hundred years that will be much faster than anything known and recorded in history. There are necessary steps to be undertaken to control the toxic emission that will soon be killing us.

To minimize the consumption of oil, petroleum and other fossil fuel, we should use energy efficiently. Energy that we use should be generated from renewable energy source, which would mean harnessing the natural energy from the sun, winds, crops, tides and waves.

Green energy is another term used to describe sources of energy that are considered to be environmentally friendly, which is also similar to the renewable sources of energy.

There are numerous ways of generating electricity and energy from renewable and natural sources that generate clean and safe energy. Wind, sun, and heat can generate electricity for less price and less carbon emission than those of coal and even gas.

Shifting the world's attention to alternative fuel source other than relying on fossil fuel is among the solutions in resolving the drastic climate change. Greenpeace cited that with renewable energy and using it smartly, can deliver half of the world's energy needs by 2050. Greenpeace also cited that it is feasible to reduce carbon dioxide emission to almost 50 percent within the next 43 years.

Governments are taking steps to use and tap alternative energy sources as main source of energy. The European Union leaders made an agreement in March 2007 to ensure that 20 percent of their nation's energy should come from renewable fuels by 2020. This is part of their effort to cut carbon dioxide emissions and other greenhouse gas. There are even governments offering incentives to their residents who are using green energy.

Alternative energy source may not be the only way to reduce the greenhouse emission that human activity produce. There are simple ways in which we can do to contribute in reducing toxic gas emission and mitigate global warming.