Beyond the Two-Degree Target
BERLIN – In international climate-policy circles, there is broad consensus regarding the target of limiting global warming to a maximum of two degrees Celsius above pre-industrial levels. Still, barring a breakthrough in United Nations negotiations in the near future and a reversal in current emissions trends, meeting that two-degree target is well-nigh impossible.
But if world leaders abandon this target, they will have to make a fundamental strategic decision regarding the structure and stringency levels of a new climate goal. So international climate policy needs a paradigm shift. The science-based approach of translating a global temperature cap into precise national emission budgets is politically unfeasible. Instead, countries with a strong climate-policy agenda should advocate dynamic formulas for setting targets.
The two-degree target is the primary point of reference for today’s climate debate. A corresponding rise in the global mean temperature is usually seen as the limit beyond which the effects of climate change could become dangerous. But, contrary to widespread belief, the last assessment report of the UN’s Intergovernmental Panel on Climate Change (IPCC) did not call for the two-degree target, which, since the mid-1990s, has acted as a catchy symbol and point of orientation for an ambitious but realistic global climate agenda.