The Importance of Setting Limits

The goal for the Climate Change Conference in Copenhagen of a global agreement on reduction of CO2 emissions is now being turned down into instead an agreement to limit global warming to 2 degrees Celcius.  Swedish Minister of Environment Andreas Carlgren leading EU at the conference expresses his ambition as follows:

• The is key is to continue to keep the 2 degree limit within reach.
• If we focus on the 2 degree limit, then we can put aside discussions on emission control.

What a clever idea! But why limit this clever limit idea to only global warming? Why not agree to limit 

• global cooling to - 2 degrees and avoid the coming ice age?
• global economy growth to minimum 2% and avoid economic downturn?
• the speed of light to 200.000 km/s?
• budget deficits to 2%?
• bank loan losses in the Baltic states to 2%?

Of course without any discussion of how this may be accomplished. But do voters really swallow such arguments? Or only politicians?