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Naturally occuring greenhouse gases also include water vapor, ozone and few other gases.
Without a natural greenhouse effect, the temperature of the Earth would be about zero degrees F (-18°C) instead of its present 57°F (14°C).
Human activity has been increasing the concentration of greenhouse gases in the atmosphere. There is no scientific debate on this point. Pre-industrial levels of carbon dioxide (prior to the start of the Industrial Revolution) were about 280 parts per million by volume (ppmv), current levels are about 370 ppmv and the expected level for the year 2065 is 560 ppmv. Since the beginning of the Industrial Revolution, atmospheric concentrations of carbon dioxide have increased nearly 30%, methane concentrations have more than doubled, and nitrous oxide concentrations have risen by about 15%.
Scientists apologize that the increasing of the concentration of greenhouse gases and chemicals in the atmosphere lead to the global warming.
Global warming is a changing of the climate on the Earth that made life on the Earth possible.
What are the potential effects of rising temperatures? Why do we call global warming an environmental problem? In general scientists believe that rising temperature will lead to increase evaporation and therefore to more precipitation. But while some regions will experience increased rainfall, others will become dryer. Another effect is the rise of the sea levels, which will result in flooding low-lying coastal areas. This may also lead to increasing the salinity of the rivers and to decrease of water supplies. And finally climate changes may cause extinction of many species of birds, animals and plants. Even now a lot of species of animals, birds, fish and plants have either disappeared completely or on the verge of extinction.
Solutions to global warming - clean energy, energy efficiency and new environmentally sound technologies - already exist. The latest report from the International Panel on Climate Change (IPCC) says that hundreds of technologies are already available, at very low cost, to reduce climate damaging emissions and that government policies need to remove the barriers to these technologies. Implementing these solutions will not require humans to make sacrifices or otherwise impede their quality of life. Instead, they will enable people to usher in a new era of energy, one that will bring economic growth, new jobs, technological innovation and, most importantly environmental protection. Wind power is already a significant source of energy in many parts of the world. It can supply 10 percent of the world's electricity within two decades. Solar power has been growing in a global capacity by 33 percent annually. Greenpeace and industry research shows that with some government support, the solar industry could supply electricity to over 2 billion people globally in the next 20 years. By 2040 solar photovoltaics could supply nearly 25 percent of global electricity demand. A report conducted by global financial analysts KPMG shows that solar power would become cost competitive with traditional fossil fuels if the production of photovoltaic panels was increased to 500 megawatts a year. A renewable power plant in Asia could have the same costs and provide the same jobs as a coal-fired plant, but with significant environmental advantages. Greenfreeze refrigeration technology, which is safe for the climate and the ozone layer, has spread around the world. It is an ideal solution for developing countries where cost and efficiency are particularly important.
Oil companies must stop exploring for more fossil fuels that the world cannot afford to burn. Governments need to subsidize renewable energy and force polluters to pay.
Acid rains
First of all I should say that the only place on earth where pure water is found is in a laboratory. Rainwater always contains small amounts of impurities. These impurities come from dust particles or are absorbed from the gases in the air. If pure water is exposed to the air it absorbs carbon dioxide to form carbonic acid and becomes slightly acidic, dropping from pH 7 i.e. neutral, to pH 5,6. Even in remote, unpopulated areas rain can reach a pH of 4,5. However, a pH of less than 4,5 in rain is almost certainly caused by air pollution.
Реферат опубликован: 20/12/2006