Like huge, ravening monsters, the top causes of global warming
are ignoring man’s attempts to stop them and continue to hit
record highs, according to the World Meteorological
Organisation. The level of carbon dioxide in the atmosphere, the
biggest single cause of global warming, rose by 2ppm (parts per
million) in 2010-2011, reaching a new record of 391ppm or 140%
of pre-industrial levels. Carbon dioxide is responsible for up
to 85% of global warming. Other greenhouse gas emissions have
also hit new highs, including nitrous oxide, which has a far
longer-lasting effect on global warming than other greenhouse
gases and is partly responsible for destroying the planet’s
protectiove ozone layer. Taken together, these three gases have
caused a 30% increase in the global warming effect since 1990,
the equivalent of 473ppm carbon dioxide. Methane is a more
potent greenhouse gas than carbon dioxide but its release into
the atmosphere had plateaued up until 2007, when it started to
rise again with increasing rapidity.