Hi monkeytester, Global Warming is actually a misnomer that was coined by a reporter. The proper scientific term is Climate Change. Basically it is caused by increased CO2 in the atmosphere which holds in heat from the sun's rays and cause the weather and temperatures around the planet to change. If it seems like there has been more instances of severe weather, drought followed by lots of rain, etc that is because Climate Change is affecting the Earth. The effect is increased by melting polar ice caps as well.
It's a natural process of Earth.It's not the first and it won't be the last.Political lies to gain a vote.Ask any real scientist why part of Antarctica always melts and he will say underwater volcanism warming the water,but the other half is growing.Al Gore never mentioned that part did he.
The earth has a respiration, just like all living organisms, it gets warmer for a while which causes greater evaporation which causes more cloud cover which causes cooling which decreases cloud cover which causes warming......etc. these cycles of heating and cooling can last for decades at a time. Back in the 1960's they were warning of another ice age.