Short introduction on Saudi Arabia’s emissions
Although CO2 is the driving force behind the temperature changes, other gases such as methane (CH4) also contribute their share to global warming, for example through the exploitation of gas fields, and emissions by livestock. While methane is emitted much less than CO2 on a global scale, it is a much stronger greenhouse gas (GHG). Scientists estimated the relative strength of the important Kyoto greenhouse gases so that we can convert all emissions to an equivalent of CO2 emissions. For example, the emission of one ton of methane has approximately the warming effect of 25 tons of CO2. The factor of 25 reflects the climate forcing on a 100-year time horizon, following the Global Warming Potential presented in the IPCC Fourth Assessment Report (AR4).
With greenhouse gas emissions of approximately the equivalent of 675.3 mega tonnes of CO2 (Mt CO2eq), Saudi Arabia contributed 1.41% to the global greenhouse gas emissions of 2017 (rank 14 - incl. EU27 on rank 3). All emissions estimates exclude emissions and absorption from land, which result from activities such as cutting down or planting of forests (Land Use, Land-Use Change and Forestry: LULUCF). Emissions from bunker fuels (international aviation and shipping) were also excluded, as they are not accounted for in national totals.
For 2030, Saudi Arabia’s global contribution to greenhouse gas emissions is projected to increase to approximately 1.64% (920.1 mega tonnes of CO2 equivalent / rank 10 - incl. EU27 on rank 4). The emissions projections for Saudi Arabia were derived by downscaling the Shared Socio-Economic Pathways’ (SSPs) “Middle-of-the-Road” baseline marker scenario SSP2. These pathways describe certain narratives of socio-economic developments and were, i.a., used to derive greenhouse gas emissions scenarios that correspond to these developments. SSP2 is a narrative with little shifts in socio-economic patterns compared to historical ones, and is connected to medium socio-economic challenges for both climate mitigation and adaptation. While different models were used for each storyline, per SSP (SSPs1-5) one model was chosen as representative “marker scenario”. As the emissions projections are not readily available on country-level, but national estimates are important, the pathways were downscaled in the aftermath. In 2017, Saudi Arabia represented 0.43% of the global population. Its Gross Domestic Product (GDP) in 2017 were 1.14% of the global GDP.
Looking at the highest contributing emissions sectors and gases separately, we find that in 2017 the highest contributing emissions sectors were Energy and IPPU (83.6% and 9.3%). Amongst the greenhouse gases that are considered in the Kyoto Protocol, the strongest contributor with 81.0% was CO2. This was followed by CH4 emissions, with a significantly lower share of 16.3%. When not considering the sectors and gases independently, but the sector-gas combinations instead, Energy CO2 and Energy CH4 (72.2% and 11.2%) represented the largest emissions in 2017.
Greenhouse gas mitigation and Nationally Determined Contribution (NDC)
In 2015, the majority of countries agreed to the Paris Agreement (PA), with the goal of “Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change” (Article 2.1.a). Countries stated their pledges and targets towards achieving the PA’s goals in their Nationally Determined Contributions (NDCs). With Article 4.4 of the Paris Agreement, Parties decided that “Developed country Parties should continue taking the lead by undertaking economy-wide absolute emission reduction targets. Developing country Parties should continue enhancing their mitigation efforts, and are encouraged to move over time towards economy-wide emission reduction or limitation targets in the light of different national circumstances.”
Following its 2016 NDC, “The Kingdom will engage in actions and plans in pursuit of economic diversification that have co-benefits in the form of greenhouse gas (GHG) emission avoidances and adaptation to the impacts of climate change, as well as reducing the impacts of response measures.” (NDC, p. 1). Furthermore, Saudi Arabia provides an estimate of the resulting absolute reductions, as “The actions and plans outlined in this submission seek to achieve mitigation co-benefits ambitions of up to 130 million tons of CO2eq avoided by 2030 annually through contributions to economic diversification and adaptation.” (NDC, p. 1). We classify the country’s contribution as conditional, as “These ambitions are contingent on the Kingdom’s economy continuing to grow with an increasingly diversified economy and a robust contribution from oil export revenues to the national economy. It is also premised on the fact that the economic and social consequences of international climate change policies and measures do not pose disproportionate or abnormal burden on the Kingdom’s economy.” (NDC, p. 1).
Even though the base year for the BAU projections the NDC is based on is given as the year 2000 (NDC, p. 2), the quantitative information needed to estimate Saudi Arabia’s target emissions is not provided. Therefore, target quantifications rely on “external” (non-NDC) projections of the 2030 BAU emissions, from which the absolute reduction of 130 MtCO2eq can then be subtracted. The availability of national estimates of emissions mitigation targets and pathways in line with countries’ NDCs is of great importance when, e.g., aggregating to global emissions to then derive, i.a., the resulting end-of-century warming levels. Information on the targeted sectors and gases is not clearly given in the country’s NDC. Based on the stated measures, we assess the sectors Energy, Agriculture, LULUCF, and Waste as covered (NDC, p. 3-4), as well as the Kyoto GHGs CO2 and CH4 (NDC, p. 3). Based on historical emissions from PRIMAP-hist v2.1 HISTCR (exclLU and exclBF) for the year 2017, this results in approximately 88% of national emissions being targeted.
Regarding LULUCF, the NDC includes the following measures, “Reduced desertification: Undertake measures to enhance desertification management. Support actions that will promote the stabilization of sand movements around cities and roads, while increasing sinks for capacity through using green belts as barriers. Develop and enhance arid and semi-arid rural areas through various natural resource conservation activities, biodiversity and eco-system based adaptation efforts. The objective is to improve soil quality, water, pasture and wildlife resources through a system of protected areas and reserves. Mitigation co-benefits may include those relating to reducing land degradation and improving land management practices, especially for agriculture and forestry.” (NDC, p. 4).
The NDC-assessment is based on Saudi Arabia’s NDC submitted to the UNFCCC in November 2016. Relying on “external” non-NDC data (SSP2) and the assessed national share of targeted emissions, for Saudi Arabia we quantify the 2030 conditional target as 781.0 Mt CO2eq AR4 (absolute reduction compared to Business-As-Usual: -130 MtCO2eq, inclLU).
The Figure below provides additional information, regarding both the baseline emissions used in our assessment and the quantified mitigated pathways for Saudi Arabia.
Baseline emissions and mitigated emissions pathways based on the country’s Nationally Determined Contribution. In terms of national emissions, we look at the SSP2 baseline marker scenario, and the emissions of all IPCC sectors. Contributions from LULUCF are excluded (exclLU), and the emissions are based on GWPs from AR4. The left panel (a) shows the baseline emissions, indicating the contributions of the Kyoto Greenhouse Gases CO2, CH4, N2O, and the basket of F-gases to the national emissions. If we could extract baseline data exclLU from the NDC, you can see their values as black squares (converted from GWP SAR to AR4 if needed). In the right panel (b), the quantified mitigated emissions pathways are shown, based on information from the country’s NDC and also on non-NDC emissions baselines, per target conditionality and range (marked un-/conditional best/worst). Even though not all countries have targets with different conditionalities or ranges, we need assumptions for all four cases to build one global pathway per conditionality plus range combination and to derive corresponding temperature estimates. Therefore, we indicate these four pathways here. Per combination, we performed several quantifications with differing assumptions and show the median and the minimal and maximal pathways here. Additionally, if we could quantify the targets based on data extracted purely from the NDC - or if the targets were directly given in absolute emissions, these targets are shown as squares (in the GWP originally given in the NDC).
Data sources and further information
- Historical emissions: PRIMAP-hist v2.1 (Guetschow et al., 2016, 2019).
- Historical socio-economic data: PRIMAP-hist Socio-Eco v2.1 (Guetschow et al., 2019).
- Projected emissions and socio-economic data: downscaled SSPs (Guetschow et al., 2020, 2020).
- NDC quantifications: NDCmitiQ (Guenther et al., 2020, 2021).
- GDP is given in purchasing power parity (PPP).
- Main emissions sectors (Intergovernmental Panel on Climate Change, IPCC): Energy, Industrial Processes and Product Use (IPPU), Agriculture and LULUCF (Land Use, Land-Use Change and Forestry), also named AFOLU (Agriculture, Forestry and Other Land Use), and Waste.
- Kyoto GHG: basket of several GHGs, namely carbon dioxide (CO2), Methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6), and since the second Kyoto Protocol period (2013-20) additionally nitrogen fluoride (NF3).
- Global Warming Potentials (GWPs): GHGs have very different warming potentials. To make them comparable and for aggregation purposes, GWPs are used (how much energy will 1 ton of a certain gas absorb over a defined period of time, relative to the same mass of CO2?).
1 Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany