The Earth Is Heating Up

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Global warming is commonly referred to as an increase in the temperature of the lowest layers of Earth's atmosphere. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Primary greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone . Carbon dioxide, as well as other greenhouse gases, is a very important factor in the vital cycles which sustain life on this planet, plants use carbon dioxide in photosynthesis and release oxygen necessary to maintain the lives of animal species, who through exhaling return carbon dioxide in atmosphere, completing the cycle .Greenhouse effect is a natural process which made life on Earth feasible. The temperature of Earth's atmosphere is regulated by a process in which the quantity of energy Earth gets from the Sun is poised by the amount returned back into space. Greenhouse gases in atmosphere let the energy in and prevent it from escaping, directing it back to Earth's surface . By the greenhouse effect, in the discussions of the global warming and other environmental problems, people mean "the enhanced effect which is caused by the increase of greenhouse gases from human sources” . Science brings different theories about the primary causes of the global warming of atmosphere. Eventually, the processes that happen in the environment are so complex even on local scale, that analyzing causes and effects of global processes leads scientists to controversial conclusions. Most scientists agree on certain facts. Arguments start upon interpretation of these facts. Concentration of atmospheric carbon dioxide, which the scientists agree determines the temperature of Earth, has increased from a value of about 275 parts per million before the Industrial Revolution to about 360 parts per million in 1996. The rate of increase has also been accelerating in this period of time . The researches made by different groups of scientists came nearly with the same results on the rise of the near surface atmospheric temperature. The Intergovernmental Panel on Climate Change officially concluded that it has increased by somewhere in between 0.5 to 1.1 degrees Fahrenheit since the last century. The sea level has risen four to ten inches during the same period of time . The main issue which troubles not only scientific, but also political arguments is mankind’s contribution to the current warming of atmosphere. In 1924 M. Milankovitch, a Serbian mathematician, worked out a theory about the causes of changes in the Earth's ice cover . Milankovitch supposed that small variations in earth's orbit can lead to the "extreme" changes in climate. In the period of about forty one thousand years the axis' of rotation angle changes between 22 and 24.5 degrees resulting in melting or expanding of the glacier ice sheets in the Northern Hemisphere and, consequently, in the warming or cooling of climate . Recent techniques let scientists see that for the last several million years, glaciers have varied accordingly to variation of Earth's orbit. This have been causing so called ice ages. The last one lasted from one hundred thousand years ago to 10,000 B.C. A large quantity of carbon dioxide is dissolved in the ocean water. The quantity of it always comes to equilibrium with the amount of it in atmosphere. Based on the very detailed statistical study of the correlation of the ocean's temperature and the concentration of carbon dioxide in the air, held by the Bell Telephone Laboratories in the period of 1958 - 1988, some scientists conclude that it may not necessarily be the increase of the concentration of the atmospheric carbon dioxide that causes the warming of atmosphere. The study showed that a rise in ocean temperature actually preceded the rise of carbon dioxide concentration in atmosphere . Other theory states that the...
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