Burden sharing in the implementation of the Climate Convention

•Implementation of the Kyoto Protocol did not reduce global GHG emissions growth.•Defining burden sharing of emissions is key to the success of climate negotiations.•Accounting for historical emissions involves too many uncertainties.•Developed countries have already presented pledges to reduce their emissions by 2020.•Emissions of developing countries became dominant and they must act to reduce them.

Burden sharing in the actions needed to reduce greenhouse gas emissions has proved so far to be the most intractable problem in the implementation of the Climate Convention and the Kyoto Protocol.We analyzed the contribution of non-Annex I countries to the GHG emissions in the period 1850–2010 to assess their relative contribution to total GHG emissions. In the period 1850–1990 non-Annex I countries represented 44% of the total but this contribution increased in the period 1990–2010 to 56%. If we extrapolate present trends to 2030 they will represent 69% in the period 1990–2030. The “historical responsibility” of Annex I countries is therefore decreasing. If we take 1990 as the starting year in which the Climate Convention recognized clearly that greenhouse gases are interfering dangerously with the climate system, it is evident the need of non-Annex I countries to engage with Annex I countries in the effort to reduce emissions. We present three options for the burden sharing in such effort.