The Paris Agreement and NDCs: are the national mitigation targets sufficient to stay below the 1.5-2°C limit?

Short introduction on Colombia’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 166.7 mega tonnes of CO₂ (Mt CO₂eq), Colombia contributed 0.34% to the global greenhouse gas emissions of 2017 (rank 41 - 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, Colombia’s global contribution to greenhouse gas emissions is projected to increase to approximately 0.40% (224.1 mega tonnes of CO₂ equivalent / rank 40 - incl. EU27 on rank 4). The emissions projections for Colombia 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, Colombia represented 0.64% of the global population. Its Gross Domestic Product (GDP) in 2017 were 0.56% 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 Agriculture (53.3% and 29.0%). Amongst the greenhouse gases that are considered in the Kyoto Protocol, the strongest contributor with 50.6% was CO₂. This was followed by CH₄ emissions, with a share of 34.0%. When not considering the sectors and gases independently, but the sector-gas combinations instead, Energy CO₂ and Agriculture CH₄ (45.5% and 16.7%) 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.”

In its NDC, Colombia commits to emit a maximum of 169.44 million tCO₂eq [AR5] in 2030 (equivalent to a 51% reduction in emissions compared to the emission projection in 2030 in the reference scenario), to initiate a decrease in emissions between 2027 and 2030 tending towards carbon-neutrality by mid-century, to establish carbon budgets for the period 2020-2030 no later than 2023, and to reduce black carbon emissions by 40% compared to 2014 levels (NDC, p. 34, GWP: p. 35). The updated 2020 NDC is based on a long-term vision that is established by the aspiration towards carbon neutrality manifested by the country at the United Nations Climate Action Summit in September 2019, and which will be reflected in the Long-Term Strategy E2050, a medium-term vision to 2030 that is established through the Colombian Strategy for Low Carbon Development and the Comprehensive Strategy for Deforestation Control and Forest Management, and a short-term vision through the National Plan for Development (NDC, p. 30).

Even though the contribution consists of an unconditional and conditional part, it is not clear which share is unconditional (NDC, p. 6-7). Colombia is in the process of quantifying the costs of implementing the NDC and the financial structuring required from the national, international, public and private spheres. International cooperation related to climate change has increased since 2015 on issues such as the fight against deforestation, implementation of renewable energy, and sustainable mobility in cities, which has allowed Colombia to move towards a more ambitious NDC, with additional contributions and impact. The continuity of international cooperation will be key to continue on this path in all aspects of Colombia’s NDC.

With a reference year of 2015 (NDC, p. 34), the country projects BAU emissions of 345.80 MtCO₂eq AR5 in 2030 (NDC, p. 31), including an emissions contribution by LULUCF of 117.94 MtCO₂eq AR5 (NDC, p. 32), and the absolute target emissions for a 51% reduction compared to BAU are 169.44 MtCO₂eq AR5 (inclLU). 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. The country clarifies that the national data for the reference scenario were consolidated by calculating and aggregating sectoral emissions in accordance with the data available at the national level, comprising all sectors of the economy and covering 100% of emissions and IPCC categories for the year 2014 (NDC, p. 34). Hence, all main IPCC emissions sectors (Energy, IPPU, Agriculture, LULUCF, and Waste) are assessed as covered. All Kyoto GHGs besides NF₃ are explicitly listed as included (NDC, p. 35). For NF₃, e.g., PRIMAP-hist v2.1 has no historical emissions data available for Colombia. NF₃ has only been added to the Kyoto GHG basket for the Kyoto Protocol’s second period. It is merely reported by few countries and contributed less than 0.01% to global Kyoto GHG emissions in 2017 (exclLU and exclBF, based on PRIMAP-hist v2.1 HISTCR, in AR4, with its share being influenced by the few available data). In total, our assessment of covered sectors and gases results in an estimated 100.0% of 2017’ emissions being targeted by the NDC (based on PRIMAP-hist v2.1 HISTCR exclLU, in AR4), in accordance with what is stated in the NDC regarding the year 2014.

For the land component, the stated mitigation goal contemplates a reduction in emissions from deforestation equivalent to reducing the deforestation rate to 50,000 ha/year in 2030 (NDC, p. 35). In its NDC, Colombia furthermore declares that it intends to participate in cooperative approaches under Article 6 of the Paris Agreement, in accordance with the decisions adopted by the CMA on the matter and with the environmental integrity approach indicated by the San Jose Principles (NDC, p. 35).

The NDC-assessment is based on Colombia’s NDC submitted to the UNFCCC in December 2020. The document was submitted in Spanish, and the above-assessment is based on our best understanding of the Spanish NDC.

The Figure below provides additional information, regarding both the baseline emissions used in our assessment and the quantified mitigated pathways for Colombia.

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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).

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FIG 1

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?).