Gore is a political bum who makes money by spouting what hard working scientists find, (had to get that out ot the way)
The debate isn't whether the earth is warming or not, but if it is man made, that being the case, NASA has also discovered that mars is heating up as well, though this isn't proof against humans contributing, it does show that we are encountering a sun spot.
Plus most models are not able to apply all variables without making it too complex or unpredictable (otherwise useless), also it isn't even agreed upon what effects certain variables have. Would an increase in clouds (due to warming of the oceans) warm or cool the earth? There is disagreement on this, a basic yet major variable.
Thus I say, let the scientists do their stuff, and let the politicians handle the government.
Also take into consideration that we have experienced a global cooling from 1930 to 1980. There are different theories on that as well.