Global warming is the in the
temperature of planet due to
accumulation some gases in the
, especially gases that retain
solar energy reflected by planet
surface. The main that causes the
global is carbon dioxide, CO₂,
other gases act as “ gases”
too, like methane, , and nitrous
oxide, N₂O. exaggerated increase of
carbon in the atmosphere has
caused by the burning fossil
fuels (mainly oil coal) in industrial
and societies and by forest .
(It is important to that the natural
warming by gases of the
is fundamental for the
of the planet
temperature.)

of studies sponsored by
United Nations stated that global
warming may cause -threatening
transformations to the planet the
near future. Countries are the
biggest emitters carbon dioxide, like
the States and China, however,
ignore the warnings and
to largely contribute to
danger.

Global warming is of the most
polemic issues today.