For the emission standards to deliver actual emission reductions it is crucial to use a test cycle that reflects real - world driving conditions. (en.wikipedia.org)
No one is going to be able to predict what actual emissions of the various greenhouse gases will be over the next 100 years. (realclimate.org)
The existing nine - state cap is set at 165 million tons of carbon dioxide, well above actual emissions. (readme.readmedia.com)