The European Union often emphasizes that it is pursuing a “science-based” climate policy. The European Council’s long-term emission reduction target of 80-95% by 2050 explicitly refers to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Thus, it came as a surprise for many European policymakers and stakeholders that the latest IPCC report did not offer any specific guidelines on future EU climate targets. Brigitte Knopf from the Potsdam Institute for Climate Impact Research (PIK) and Oliver Geden from the German Institute for International and Security Affairs (SWP), two leading institutions in the field of scientific policy advice, argue in line with the philosophy of the new IPCC report that the question of adequate EU targets for 2030 or 2050 cannot be based purely on science, but must ultimately be decided in the political arena.

In January 2014, the EU Commission proposed a new greenhouse gas (GHG) reduction target of 40% for 2030. In the accompanying Impact Assessment, the Commission refers to the European Council’s long-term target of a 80-95% GHG emissions reduction by 2050 (compared to 1990 levels). This in turn is based on the IPCC’s Fourth Assessment Report (AR4), published in 2007. Although the European Council hasn’t been able to agree on a specific EU target for 2030 so far, the 28 heads of state and government stated in March 2014 that the 2030 climate target will be “fully in line with the agreed ambitious EU objective for 2050”.

As it happens, only three weeks later, IPCC Working Group (WG) III on mitigation presented its part of the Fifth Assessment Report (AR5). In this report – the result of “four years of intense scientific collaboration by hundreds of authors from around the world” – the IPCC “responds to the request of the world’s governments for a comprehensive, objective and policy neutral assessment of the current scientific knowledge on mitigating climate change.”

So what are the implications of the IPCC’s findings  for EU policy making? Has the range of a 80-95% reduction by 2050 been updated? And what does the IPCC have to say about an adequate EU target for 2030?

Emission reduction targets in IPCC AR4 and AR5

While all nations have agreed on limiting global temperature increase to 2°C (relative to pre-industrial levels), it is less clear what this means for individual countries or regions in terms of emission reductions. In IPCC AR4, numbers for GHG reduction levels by 2020 and 2050 were given (see Table 1). This table provided only a very rough classification in Annex-I and Non-Annex-I countries (referring to the groupings used in the UN Framework Convention on Climate Change of 1992). It showed the required emission reductions based on different ethical principles. For the 450ppm-CO₂-equivalent scenarios, roughly equivalent to a 2°C trajectory, Annex-I countries (mainly the industrialized ones) were given a 25-40% reduction range by 2020 and 80-95% by 2050.

Table 1: The range of the difference between emissions in 1990 and emission allowances in 2020/2050 for various GHG concentration levels for Annex-I and Non-Annex-I countries as a group. Source: IPCC AR4 WGIII, Box 13.7

Although this table was never meant to be normative in the sense that for limiting temperature increase to 2°C industrialized countries should reduce their emissions by 80-95% by 2050, most people did interpret it like this. In fact, it would have been more accurate to interpret this in a descriptive way, in the sense that “the scenarios in the IPCC AR4 based on different ethical principles show that achieving 2°C at a global level equates to industrialized countries reducing their emissions by 80-95%, according to the models.”

Nevertheless, a reduction of at least 80% by 2050 found its way into many energy and climate strategies, for example in Germany’s Energy Concept, in the UK, Lithuania, Denmark, Finland and also at the EU level. For the EU, the number of 80-95% overall GHG reduction is currently of particular importance as the Commission derived its suggestion for a potential target for 2030 from this long-term target, which the Commission interprets in its Impact Assessment as 80% domestic reduction within the EU.

Many policymakers and NGOs had assumed that IPCC AR5 would deliver updated numbers for industrialized countries’ emission reductions, which might have opened the door for even more ambitious EU targets. But it didn’t happen. A closer look into the Working Group III report not only shows that updates for 2020/2050 are missing, but that the prominent AR4 ranges even disappeared. There’s no “IPCC target” of 80-95% by 2050 anymore. What’s behind the new IPCC approach, and what does it mean for EU climate policy?

New IPCC report stresses the aspect of ethical judgments

The most important thing to note is that in the AR5 the IPCC stresses that the decision about the adequate global level of mitigation and the issue of effort sharing among individual countries involves ethical considerations:

“Many areas of climate policy-making involve value judgements and ethical considerations. These areas range from the question of how much mitigation is needed to prevent dangerous interference with the climate system to choices among specific policies for mitigation or adaptation. Social, economic and ethical analyses may be used to inform value judgements and may take into account values of various sorts, including human wellbeing, cultural values and non‐human values” (Source: Summary for Policymakers of IPCC WGIII)

This has a strong implication, as the IPCC clearly emphasizes a division of labor between science and policy with this statement, and recognizes that the question of adequate targets on global or national levels cannot be solely set by scientists. Policy objectives and their means can only be evaluated in light of their practical consequences and when new scientific evidence turns up, this might change the political target. This implies that target setting is an iterative process between scientists and policy makers.

This means that  IPCC Working Group III with its scientific perspective, based on economic and ethical analysis, can only inform the debate and point out the consequences of different ethical principles, but cannot decide what the “correct” level of emission reduction for example for the EU would be, as the ethical judgments in this context are highly controversial. As a consequence, no direct advice for a specific target is given.

Domestic emission reductions

To inform the political debate, the IPCC did run a huge number of scenarios for assessing the feasibility of the 2°C target and of 1.5°C and 4°C worlds, including scenarios with delayed participation and scenarios assuming technology failures. From these scenarios information about regional emissions reductions is available.

Table 6.4. in the IPCC AR5 (see Table 2) gives an overview of regional peak years for emissions and emission reductions in 2030 compared to 2010 for domestic emission reductions (excluding offsetting mechanisms) required for limiting temperature increase to 2°C. The yellow bar highlights the numbers that are relevant in the context of keeping the 2°C limit with a high probability. While the AR4 only distinguished between Annex-I and Non-Annex-I, the regional disaggregation is now given for five world regions: OECD-1990, non-OECD Asia (ASIA), Latin America and Caribbean (LAM), Middle East and Africa (MAF), and Economies in Transition (EIT). This regional disaggregation implies that the EU28 region is not given as one region, but is divided into OECD-1990 and EIT, i.e. mainly into Western Europe and Eastern Europe. As a consequence, the IPCC does not give a number for emission reductions for the EU as a whole, but only separated between OECD-1990 and EIT.

Table 2: Regional peak year of CO2 emissions and emissions reductions by 2030 compared to 2010 for 430-530 ppm CO2-eq and 430-530 ppm CO2-eq scenarios. Numbers are averages across models, numbers in parenthesis show the interquartile range across scenarios. For 2°C the range of 430-530 ppm CO2-eq is relevant (yellow bar). Source: IPCC AR5, Table 6.4.

Again, this table is not normative, therefore it should be read like an if-then statement: “If the world wants to limit temperature increase to 2°C (here expressed as 430-530 ppm CO₂-eq), then the cost-effective global implementation of this target would suggest domestic emission reductions in OECD-1990 and EIT of 32% by 2030 relative to 2010, according to the models”. These regional reduction numbers are given for CO₂ and not for GHG emissions. Moreover, only numbers for 2030 are given, not for 2020 or for 2050, so no direct comparison of the 80-95% range from the AR4 with new scenario outcomes in AR5 is available.

Also the base year has changed from 1990 to 2010. As a consequence, from the data given in the table it is not straightforward to deduce numbers for Europe, as emissions have developed quite differently in the OECD-1990 region and in the EIT region, with an increase, respectively a decrease between 1990 and 2010.

As a proxy, the historical numbers for the EU as a whole can be considered, where CO₂ emissions – unlike in the rest of the OECD – have considerably decreased between 1990 and 2010 by 13%. So if the baseline is taken as 1990, as the EU does, this would translate to 41% domestic CO₂ reduction[1]. Our own independent model comparison comes to a different conclusion, where results show that a more ambitious CO₂ reduction of 47% by 2030 is in line with a long-term reduction of 80% GHG by 2050.

Although in IPCC AR5 no number for domestic reduction for 2050 is given, the number can be deduced from the IPCC AR5 Database that is now very transparently available and open for everyone. Own additional calculations based on exactly the same data set show that for 2050 a cost-effective domestic effort would require an average reduction of 75% for both OECD-1990 and EIT between 2010 and 2050 (and 40%, 85%, and 44% for ASIA, LAM, MAF).

Effort-sharing approaches

All domestic CO₂ reduction numbers are related to globally cost-efficient emission reduction pathways, where all technologies are available and where no delay in global action is assumed. The above analysis does not consider ethical aspects related to effort-sharing of the associated mitigation costs. However, by assuming a global carbon market, the domestic emission reduction and the accompanying mitigation costs can be separated from the question who is paying for them, for example by offsetting. Different effort-sharing regimes that distribute the emission allowances according to a specific ethical principle are discussed intensively in the literature and in the political arena. Currently the distributional question and fair and equitable effort sharing is also heavily discussed within the EU between the different Member States. This discussion was taken up very prominently in the European Council conclusions of March 2014.

In the context of global burden sharing, the IPCC provides two additional figures for the distribution of emission allowances based on different effort-sharing regimes. It is important to note that the emission allowances and with it the distributional impacts not only depend on the overall global climate stabilization target that is aimed for, but also strongly on the ethical principle that is applied. Concrete numbers are not given in the text, only figures with huge ranges and considerable differences between the ethical concepts.

For example, based on the so-called “capability approach”, OECD-1990 would have emission allowances in 2030 of about 38% less than their 2010 emissions, while for an “equal per capita approach” a much stronger reduction of allowances by about 83% between 2010 and 2030 would be required (median values in Figure 6.28).

A similar figure (Figure 6.29) shows the ranges for emission allowances in 2050 for various global concentration targets (see Figure 1) averaged over different effort-sharing categories. Although a direct comparison is difficult because of different scenario categories and a different base year, this figure is in principle the one that is most comparable with the Table in AR4 (Table 1). However, the uncertainty ranges here are so large (for example ranging from about 55-100% reduction for OECD-1990 in the categories of 430-530 ppm CO₂-equivalent) that translating them into targets makes no sense.

Figure 1: Emission allowances in 2050 relative to 2010 emissions for different 2100 CO₂eq concentration ranges by all effort-sharing categories except (except one). Source: IPCC AR5 WGIII, Fig. 6.29.

 IPCC conclusions for the EU debate on 2030 targets

So what can be concluded from IPCC AR5 for the debate about Europe’s 2030 emissions reduction targets? In fact, there is no concrete number given for the EU, as the regional aggregation only gives numbers for OCED-1990 and economies in transition EIT separately. Moreover, the base year has changed from 1990 to 2010, so no direct comparison with numbers form AR4 is possible. The focal number of 80-95% GHG reduction by 2050, which was given in AR4, is neither updated, nor referred to in AR5.

But there is one important innovation in the new IPCC report. The most important message for deducing national or regional targets is that targets have to be set politically. Scientists can inform the debate, based on if-then statements, but as Ottmar Edenhofer, Co-Chair of IPCC WGIII, puts it:

“Judgments over the choice of appropriate discount factors, equity weights, technological risks, etc. are societal choices and cannot and must not be decided by scientists. Experts have no better moral judgment than the ordinary citizen. […] Scientists have no legitimacy whatsoever to make value judgments for society at large in their role as scientists. Nevertheless, without science, questions over optimal stabilization levels and technology choices cannot be answered in an informed way.”

In contrast to previous assessment reports of the IPCC, the AR5 makes it clear that we need a division of labor between science and policy-making and an iterative process between the two spheres. In that sense, the IPCC rejects the request by politicians, to decide on the adequate temperature level, its feasibility and a fair effort sharing scheme. Those who would like to see scientists as advocates for strong mitigation might complain about this. However, in the end this division of labor and the disentangling of the different roles of science and policy-making is of high value for an informed debate. That includes the debate on the question which target to set for 2030 within Europe and which effort-sharing principle to consider among the European Member States.

About the authors

Brigitte Knopf (@BrigitteKnopf ) is head of the research group ‘Energy Strategies Europe and Germany’ and deputy head of the research domain ‘Sustainable Solutions’ at the Potsdam Institute for Climate Impact Research (PIK) and is one of the authors of the new report of the IPCC WGIII. Oliver Geden (@Oliver_Geden) is a Senior Research Fellow at the German Institute for International and Security Affairs (SWP), Berlin and currently a Visiting Fellow at the Swiss Federal Institute of Technology (ETH), Zurich.

[1] A decrease from the level of 100% to 87% between 1990 and 2010 in addition to a decrease from these 87% by 32% to a level of 87%*68% = 59% by 2030 leads altogether to reduction by 41% between 1990 and 2030.