Meeting the 2 degree target. From climate objective to emission reduction measures

Increase in global greenhouse gas emissions will need to be turned into a decrease around 2020 in order to reach a 2°C target

Limiting temperature increase to a maximum of 2°C has been proposed to avoid dangerous anthropogenic climate change. Without additional policy, trends in greenhouse gas emissions will result in a temperature far above this target. A new PBL report gives an overview of the implications of the 2°C target, by systematically presenting information along the causal chain of climate change. In order to have at least 50% chance of staying below 2°C, atmospheric greenhouse gas concentrations need to be limited to 400-450 ppm CO₂-equivalents in the long run. To reach this, the increase in global greenhouse gas emissions will need to be halted and turned into a decrease by around 2020. In 2050, global emissions would need to be reduced by 35-55% compared to 1990. Meeting such targets requires considerable emission reductions in high-income countries, but also early involvement of other major economies in climate policy. The emission reductions can be achieved with known techniques. The overall macro-economic impacts of stringent climate policy are expected to be modest on a global level, although considerable investments are needed. The most significant challenges are to reach consensus on the contributions from different countries and sectors, and to put into place the right policies that lead to innovation and fundamental transitions.