GREENHOUSE EFFECT


     The normal cycle of the carbon in the nature is the following:

ciclo do carbono


    The carbonic gas enters in the atmosphere starting from the breathing of the animals and vegetables, of the decomposition and of the burning of organic substances and of the activity of the oceans. To proceed, it returns to the soil through the photosynthesis of the terrestrial plants and of the oceanic plânctons. The outline also shows as organic sediments took to the formation of the mineral coal and petroleum, in a process that took millions of years.
    In the last centuries, it is made calculations that the man increased in 25% the carbon dioxide concentration in the atmosphere, as a consequence of the industrial activity and use of vehicles, burning fuels of fossil origin, as gasoline, oil and other. The Worldwatch Institute evaluates that in a single day, the humanity and their machines throw in the atmosphere more carbon gas than all their ancestors before the Industrial Revolution. However, a part of the responsibility can be credited to natural causes, as volcanic activity and spontaneous fires in the forests.
    The intensification of the greenhouse effect was, with certainty, a consequence of the human activities. Larger amounts of CO2 and gas-greenhouse in the atmosphere absorb infrared radiation more and more emitted by the Earth, encapsulating the heat and impeding that this escape for the external space, what transforms the atmosphere in a greenhouse.

efeito estufa


    The main cause of the greenhouse effect is the gas carbon dioxide (CO2), but there are other gases that participate in the phenomenon, see picture to proceed:

gases-estufa SOURCES OF GREENHOUSE GAS EMISSION
Sources of carbon dioxide ( CO2)
  • burning (spontaneous or not)
  • use of fossil fuels
Methane sources(CH4)
  • great flocks of bovine
  • swamps
Sources of other gases (ozone, CFCs, gases of sulfur and of nitrogen,...)
  • burning (spontaneous or not)
  • sprays
  • use of fossil fuels


    To see also: Air pollutants.

    These gases act with CO2, holding the heat that the Earth emits and they return it for the terrestrial crust. Everything functions as if the atmosphere went a gigantic greenhouse! With this, the temperature of the planet increases. It is made calculations that in the year of 2000, about 7 billion tons of carbon dioxide they were liberated in the atmosphere. According to specialists, if the greenhouse effect continues to grow in the same rhythm, the medium temperature of the Earth can increase 5,8 degrees Celsius up to 2100.
     The first signs of the global heating are already visible every place: descongelamento of the glaciers in both poles, longer summers and shorter winters, violent floods, etc...
     It is evident that to revert or to annul these effects should be an immediate priority - beginning by reducing the discharges drastically of pollutant in the atmosphere.

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