Paris Agreement hampered by inconsistent pledges, new ICTA-UAB research finds


Some countries' Paris Climate Agreement pledges may not be as ambitious as they appear, according a new study carried out by researchers from the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB).


The Paris Agreement takes a bottom-up approach to tackling climate change, with countries submitting pledges in the form of nationally determined contributions (NDCs) to greenhouse emissions. However, a study by ICTA-UAB researchers published in Environmental Research Letters reveals a lack of consistency and transparency between the various commitments.

"The Paris Climate Agreement was a step in the right direction for international climate policy. But in its current form, it is at best inadequate and at worst grossly ineffective” says Lewis King, one of the authors. The study highlights significant issues around transparency and consistency in the agreement's pledges, which may be a contributory factor towards the lack of ambition in the pledges from some parties.

According to co-author Jeroen van den Bergh, "the sum of the agreement's national pledges on greenhouse gas emission mitigation - in the form of NDCs - falls short of meeting the agreement's 2°C target”.

To shed light on the reasons behind this, the researchers analysed the different country-level commitments by categorising and normalising them to make them comparable. Four categories were identified: (1) absolute emission reductions for a target year in percentage terms relative to a historic base year; (2) the percentage reduction in emissions relative to a 'business as usual' scenario, typically to 2030; (3) the reduction in emission intensity per GDP relative to a historic base year; and (4) projects that do not include an explicit greenhouse gas emission target. The researchers assessed these categories by adding the dimensions of geographic region and emission intensity per capita.

“Our normalisation of the pledges effectively converts them all to the absolute emission reduction target format (i.e. category 1), thus indicating actual emission change - whether positive or negative - compared with a consistent base year. We found that category 1 pledges came out as having the highest ambition in terms of tangible emissions reduction. By contrast, pledges in the other three categories tend to produce low ambitions with significant emissions increases of 29-53 per cent at a global level” they say, and explain that "we found that Northern America and the EU were the only regions aiming for absolute reductions in emissions. In the Middle East and North Africa, and South Asia, substantial increases are expected."

According to professor van den Bergh, "the current formats of the pledges mean it is difficult to accurately assess and compare what the pledges signify in actual emissions terms. For example, Russia, India and Pakistan all frame their NDCs in terms of percentage reductions; Russia relative to a base year, India relative to emissions per GDP and Pakistan relative to a business-as-usual scenario”. However, after the normalisation, the pledges result in substantial percentage increases in emissions by 2030. “Not only does this make the associated pledges difficult to interpret and compare to other pledges without detailed analysis but may produce a psychological effect of reducing the ambition level due to framing the pledge as a percentage reduction even though emissions actually increase."

The researchers stress that society has the right to be able to clearly understand and compare climate change commitments by countries, including whether they are fair, ambitious and add up to international climate goals. They also indicate that providing consistent and easily comparable information about national climate goals helps with public acceptance.

"The current lack of transparency and consistency will hinder the NDC process. To move forward, we suggest the principles of transparency and consistency from the TACCC (Transparency, accuracy, completeness, comparability, and consistency) framework of the Paris Agreement are extended to the framing of the NDCs themselves. This would be easy to achieve, by having countries convert their pledges into clear emission targets relative to the most recent available base year, inclusive of all significant gases and sectors”. Not only can this help produce targets of greater ambition that are more open to external scrutiny, but it also will assist in improving effectiveness through minimising counterproductive systemic effects, such as carbon leakage from countries with strong to those with weak climate policy.


King L.C., van den Bergh J.C.J.M (2019). Normalisation of Paris agreement NDCs to enhance transparency and ambition. Environmental Research Letters

Available online:


Related news


ICTA-UAB joins the European greenhouse gas measurement network

The ICTA-UAB is one of the institutions that will join the Spanish network of the Integrated Carbon Observation System, ICOS. The research infrastructure, which is funded by European countries, measures greenhouse gases such as carbon dioxide across the European continent and the adjacent oceans.

View all news