Guiding science and policy to robust climate action

International climate policy requires scientific evidence to steer it towards robust outcomes. In 2016, the IIASA Energy Program (ENE) worked to provide this by assessing what it will take to meet goals of the Paris climate agreement, whether national climate pledges live up to those ambitions, and how to ensure that future research yields policy-relevant results.

The Paris Agreement set a target of limiting warming to well below 2°C and further pursuing efforts to limit it to 1.5°C. To understand where we are starting from, ENE researchers carried out a meta-analysis of the current emissions reduction pledges and whether they can achieve the Paris Agreement’s goals [1].

The current pledges fall significantly short of putting the world on track to the goals, the results show (see figure). The work also highlighted the fact that the relatively weak pledges in the current agreement may result in a greater reliance on controversial technologies such as bio-energy combined with carbon capture and storage to make up the shortfall in the near term.

Along with the absolute emissions’ savings, the equity of the current pledges is also a key issue. In a further study, IIASA researchers revealed that not only are current pledges not sufficient, they do not spread efforts fairly amongst countries [2].

Assessment of current Paris Agreement emissions reduction pledges. Current pledges (orange) fall far short of pathways that can limit warming to below 2°C with at least a two-out-of-three chance (blue range). Adapted from [1].

To create truly effective climate policy it is important that policymakers are aware of the non-negotiable limits that they must abide by to prevent dangerous rises in temperature. To shed light on these “geophysical limits” IIASA researchers examined a case where there was a greater than two-out-of-three chance that warming was limited to below 2°C. To achieve this, global CO2 emissions from 2016 onwards should not exceed 590–1,240 billion tons of CO2, the researchers found [3].

Oil resources and their markets play an essential part in climate change mitigation. In a 2016 study, ENE researchers demonstrated that sustained high or low oil prices could have a substantial impact on CO2 emissions. In fact, the two price extremes could result in an increase or decrease in emissions of 55-194 gigatons of CO2 by 2050—amounting to 5-20% of the cumulative emissions allowable for keeping temperature change under the 2°C threshold.

When oil prices are high, there is an effect on demand, as consumers increase efficiency to save money. However, the emissions savings are not larger than one would expect because at high oil prices other carbon-intensive fuels, such as coal, are more likely to be used—either for electricity or liquid fuel production. The team found that the emissions impact depends not just on future oil prices, but other uncertainties such as whether oil and gas prices decouple going forward; the future potential of sustainable bioenergy supplies; and the costs and availability of electric vehicles.

If the goal is to mitigate carbon substantially, the researchers conclude, high oil prices offer no substitute for climate policies [4].

Finally, in the afterglow of the Paris Agreement, many important, policy-relevant questions arose. However, these questions were often unclear to scientists without a strong understanding of policy. Capitalizing on its expertise at the science-policy interface, ENE published two perspective articles that will help catalyze policy-relevant research. One piece directly addressed the geoscience research community [5], while a second targeted the broader global environmental change community, with a focus on the Paris Agreement’s temperature goal [6].


[1] Rogelj J, den Elzen M, Höhne M, Franzen T, Fekete H, Winkler H, Schaeffer R, Sha F, et al. (2016). Paris Agreement climate proposals need a boost to keep warming well below 2°C. Nature 534: 631-639.

[2] Robiou du Pont Y, Jeffery ML, Gütschow J, Rogelj J, Christoff P, & Meinshausen M (2017). Equitable mitigation to achieve the Paris Agreement goals. Nature Climate Change 7 (1): 38-43.

[3] Rogelj J, Schaefer M, Friedlingstein P, Gillett N, van Vuuren D, Riahi K, Allen M, & Knutti R (2016). Differences between carbon budget estimates unravelled. Nature Climate Change 6 (3): 245-252.

[4] McCollum DL, Jewell J, Krey V, Bazilian M, Fay M, & Riahi K (2016). Quantifying uncertainties influencing the long-term impacts of oil prices on energy markets and carbon emissions. Nature Energy 1: e16077.

[5] Rogelj J & Knutti R (2016). Geosciences after Paris. Nature Geoscience 9: 187-189.

[6] Schleussner CF, Rogelj J, Schaeffer M, Lissner T, Licker R, Fischer EM, Knutti R, Levermann A, et al. (2016). Science and policy characteristics of the Paris Agreement temperature goal. Nature Climate Change 6 (7): 1-9.


  • Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
  • Climate Analytics, Berlin, Germany
  • Australian-German Climate & Energy College, School of Earth Sciences, The University of Melbourne, Australia
  • Potsdam Institute for Climate Impact Research, Potsdam, Germany
  • PBL Netherlands Environmental Assessment Agency, Bilthoven, Netherlands
  • NewClimate Institute, Cologne, Germany
  • Wageningen University an Research Centre, Wageningen, Netherlands
  • World Resources Institute, Washington DC, USA
  • University of Cape Town, Cape Town, South Africa
  • Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
  • National Center for Climate Change Strategy and International Cooperation, Beijing, China
  • Graz University of Technology, Graz, Austria
  • University of Exeter, Exeter, UK
  • Canadian Centre for Climate Modelling and Analysis, Environment Canada, Victoria, Canada
  • University of Oxford, Oxford, UK
  • Marianne Fay and Morgan Bazilian (World Bank)