What will happen to earth if the greenhouse gases in the atmosphere increase?

There are many different claims made by many different groups for a variety of different reasons. Let's assume that CO2 levels will keep rising for the next 100 years or so, what are the KNOWN consequences of this action? The answer is that is do not know.

There are many predicted possibilities.

Some claim an increase in tropical storms. Other groups predict a lessening of storms. The truth could be either way, currently we are in a 30 year low of overall hurricane activity.

Some claim that temperatures could rise. Other groups claim that after 100 ppm carbon dioxide saturates in terms of the driving ability. The truth could be either. We do know that temperatures have risen 0.2 degrees since 1934. This coincidences with a 80 time increase in CO2 production by man.

What we do know is that continued use of fossil fuels is not a good thing and that decreasing this dependency is a good idea.