Facts4Paris: There is no way around zero emissions.
Regardless of the temperature at which we want to stop global warming there is no way around zero carbon emissions. As the IPCC Fifth Assessment Report showed (and as the G7 Agreement picked up) by 2050 carbon emissions from the electricity sector have to be zero. In the middle of the second half of the century, all carbon emissions ought to be phased out to net zero and by the end of the 21st century, all greenhouse gas emissions ought to be around zero (implying net negative carbon emissions). It's a daunting task but a joint target that could not be clearer. The draft text agreement for Paris contains zero and decarbonisation targets.
Source: IPCC WG3 and Synthesis Report of the Fifth Assessment Report, available at www.ipcc.ch. Specifically, IPCC WG3 AR5 Figure SPM.7 middle panel for electricity sector emissions by 2050 and IPCC AR5 Synthesis Report Table 2.2, page 64.