The greenhouse effect is a well-known mechanism. It was discovered in the 19th century by Joseph Fourier. Atmospheric gas absorbs part of the energy of the sun’s rays and heats the planet. The more gas there is, the more heat is produced.
Considered the primary cause of global warming, greenhouse gas emissions are not diminishing. If the trend is not reversed, certain experts believe that the Earth’s major carbon sinks will reach saturation within several years. Developed countries continue to be primarily responsible for this pollution: half of all emissions are still produced by only 20% of humanity.
The international mobilisation, in particular around the IPCC scientists, has challenged the policies that put in place a first agreement : the UNFCCC, then a second that emerged from the first : the Kyoto Protocol. The Kyoto Protocole fixes emission reduction objectives for six major greenhouse gases by 2012.