Without this action, it is likely that a business-as-usual scenario would see emissions rise to an average of around 56 Gt of CO 2 equivalent by around 2020. Cuts in annual emissions to around 49 Gt of CO 2 equivalent would still however leave a gap of around 5 Gt compared with where we need to be—a gap equal to the total emissions of the world’s cars, buses and trucks in 2005.
That is because the experts estimate that emissions need to be around 44 Gt of CO 2 equivalent by 2020 to have a likely chance of pegging temperatures to 2° C or less.
However, if only the lowest ambition pledges are implemented, and if no clear rules are set in the negotiations, emissions could be around 53 Gt of CO 2 equivalent in 2020—not that different from business as usual—so the rules set in the negotiations clearly matter. This report, the result of an unprecedented partnership between UNEP and individuals from 25 leading research centres, underlines the complexity of various scenarios.
The Emissions Gap Report emphasizes that tackling climate change is still manageable, if leadership is shown.
In Cancun action on financing, mitigation and adaptation need to mature and move forward—supported perhaps by action on non-CO 2 pollutants such as methane from rubbish tips to black carbon emissions.