climatic change: climate and greenhouse effect

C. Our responsabilities > The addtional greenhouse effect

"In a lot of cases, the satisfaction of the human needs is at the origin of a deterioration of the environment, which risks to decrease the capacity to answer the present and future" needs on his/her/its turn (GIEC, 2001).
These are the human activities, especially by the massive exploitation of fossil fuels and the modification of the cover of the earths, that entail an increase of the atmospheric concentrations of gas to greenhouse effect (GES), that modify the balances radiatifs and offer to warm the atmosphere.

Responsibility of the different gases in the additional greenhouse effect

The different responsible gases participate more or less in the greenhouse effect via their power of warming up and their life span. Thus, even gases given out in very small quantity can reinforce distinctly and for a long time the greenhouse effect.

Main gases to greenhouse effect table settings by the protocol of Kyoto
The dioxide of carbon (CO2) comes mainly of the fossil fuels (coal, oil and gas). He/it is also descended of some industrial processes, the deforestation (for more of 15%) and the intensive agriculture. The CO2 represents about 62% of the power radiatif of gases to greenhouse effect.
Thus, we burn today coal accumulated to the Carbonaceous, there are more 300 millions of years The CO2 is given out also by the volcanic eruptions that the Earth knew.
Methane (CH4) is given out by the intensive raising of the bovine, the animal evacuations, the cultures (as rice), the fermentation of the organic garbage, the fires of forests, the use of wood for the heating and cooking, the flooding of valleys at the time of the setting in water of the dams (with the decomposition of the drowned biomass) and at the time of the transportation and the exploitation of gas and oil (flights of firedamp in the mines of coal, of gas with the pipelines, flares...). Finally note that the CH4 oxidizes in CO2.
"The monoxide of nitrogen or nitrous oxide (N2O) results intensive agriculture (manure, evacuations), the combustion of the biomass, the chemical industrial processes and sprays notably.
"The ozone results from chemical reactions of various primary pollutants as the oxides of nitrogen (NOx), the CO and the Compounds Organic Volatile non Méthaniques (COVNM) under the effect of the solar radiance. The production of ozone is bound strongly to the automotive traffic in conditions of temperatures superior to 25°C.

The broadcasts of CO2 don't stop increasing in the same way to the energizing consumption.
Note: a kg of CO2 is worth 0,2727 kg of equivalent carbon.

Currently, the energizing consumption grows of 2% per year whereas the broadcasts should be divided by two. For example, in 2000, the world consumption was equivalent to the consumption accumulated of the period 1950 to 1957.

At the end the XIXème century, the atmosphere contained about 235 Gts of carbon. From 1970, the combustion of fossil energies gave out 4,5 Gts of carbon per year, 6,4 Gts in 1990 and 7,2 Gts currently.
Half about broadcasts of carbon is absorbed by the wells natural of carbon as the oceans, the forests and living beings, the other half accumulates in the atmosphere. However, it is indispensable to decrease at least of half these broadcasts... The industrial civilization disrupted the cycle of the carbon therefore already on a global scale. And these broadcasts could be multiplied by 5 until 2 100 to such a rhythm.

The United States and Europe total to them only close to 60% of the emissions of gas to greenhouse effect of the planet!