Technically Sound and Transparent Documents

About This Route

A good NDC is concise, clear, and transparent about progress, ambition and impact. It is underpinned by “sound” documentation and analysis to provide confidence in the work done by a country.

Understanding what “sound” means in this context is important. A technically sound document comprehensively communicates all required information. It should include data derived from analyses using high-quality data and appropriate methodologies, many of which are referenced in this NDC 3.0 Navigator. Communicated information should fulfil all as many requirements as possible in order to be complete, and the data provided should be as accurate as possible, with uncertainties clearly described and minimized as much as practicable.

Transparency involves clearly explaining the assumptions and methodologies used in the NDC. The transparency of NDCs is important to the success of the process for the communication of NDCs and the consideration of NDCs under the ICTU process as well as achieving the broader aims of enabling readers to better understand the target, building trust that the target is technically sound and demonstrating ambition, all which help move towards greater collective ambition.

Whilst there is clear guidance on the information necessary to provide in NDCs, there are other areas that can be considered to help ensure that the NDC is technically sound and transparent.

What needs to be communicated?

Specific requirements communicated in UNFCCC decisions for the reporting of NDCs state that, “all Parties shall provide the information necessary for clarity, transparency and understanding” (Paragraph 6. Decision 4/CMA.1). This information, “may include, as appropriate, inter alia, quantifiable information on the reference point (including, as appropriate, a base year), time frames and/or periods for implementation, scope and coverage, planning processes, assumptions and methodological approaches, including those for estimating and accounting for anthropogenic greenhouse gas emissions and, as appropriate, removals, and how the Party considers that its nationally determined contribution is fair and ambitious, in the light of its national circumstances, and how it contributes towards achieving the objective of the Convention as set out in its Article 2” (Paragraph 9. Decision 4/CMA.1).

Paris Agreement and International Context

The Paris Agreement relies on a robust transparency framework to provide clarity on action being taken and support needed/being provided by Parties. Article 13 of the Paris Agreement states that, “In order to build mutual trust and confidence and to promote effective implementation, an enhanced transparency framework for action and support, with built-in flexibility which takes into account Parties’ different capacities and builds upon collective experience is hereby established”.

It then sets out the transparency arrangements and reporting requirements for countries and importantly notes: “The transparency framework shall provide flexibility in the implementation of the provisions of this Article to those developing country Parties that need it in the light of their capacities. The modalities, procedures and guidelines referred to in paragraph 13 of this Article shall reflect such flexibility”.

The Enhanced Transparency Framework (ETF) established under the Paris Agreement requires countries to submit Biennial Transparency Reports (BTRs) every other year beginning in 2024 [with discretion for SIDS/LDCs]. Detailed guidance on the information to be contained in the BTRs is outlined in the “Modalities, Procedures and Guidelines and guidance on formats”, which are found in decision 5/CMA.3.

As part of the Ambition Cycle, the ETF – in particular, the information reported in BTRs – provides valuable inputs to the GST, helping track progress at the national level and enable collective assessment. In this way, BTRs also influence subsequent NDCs, as Parties increase their ambition over time, tracking their progress in future BTRs.

Transparency is also a crucial concept for the NDCs themselves, and countries are required (as per Article 4.8 of the Paris Agreement) to provide “information to facilitate clarity, transparency and understanding” (ICTU) to this effect.

Reflecting the Global Stocktake

Whilst the first Global Stocktake (GST) intends to inform Parties to the Paris Agreement on their progress against its goals and encourage ambition across climate documents including NDCs, it also includes wording specific to developing clear and transparent NDCs. The GST encourages Parties to include targets that are “informed by the latest science, in the light of different national circumstances” (Paragraph 39) and to “align their next nationally determined contributions with long-term low greenhouse gas emission development strategies” (Paragraph 40).

Guidance in the GST recalls the decision that, Parties shall submit to the secretariat their next nationally determined contributions at least 9 to 12 months in advance of the seventh session of the Conference of the Parties serving as the meeting of the Parties to the Paris Agreement (November 2025) with a view to facilitating the clarity, transparency and understanding of these contributions” (Paragraph 166).

Whilst the GST does state that, “Parties shall provide the information necessary for clarity, transparency and understanding contained in annex I to decision 4/CMA.1, as applicable to their nationally determined contributions” (Paragraph 168), there is limited direct guidance to facilitate the development of technically sound and complete documents, for example through consideration of the quality of data or scenario modelling. However, the GST encourages parties to consider developing, in consultation with technical experts, practitioners and other stakeholders, as appropriate, methodologies and tools, including modelling tools, for assessing and analysing the impacts of the implementation of response measures” (Paragraph 143).

The GST also “notes the capacity challenges of least developed countries and small island developing States related to preparing and communicating nationally determined contributions” (Paragraph 41), which may impact their ability to, for example, collect high-quality data or produce complete documents. It also “requests the secretariat to facilitate the sharing of knowledge and good practices for the preparation and implementation of nationally determined contributions, including through workshops” (Paragraph 117).

With regard to ensuring technically sound and transparent documents, the GST “encourages Parties to come forward in their next nationally determined contributions with ambitious, economy-wide emission reduction targets, covering all greenhouse gases, sectors and categories and aligned with limiting global warming to 1.5 °C, as informed by the latest science, in the light of different national circumstances” (Paragraph 39). It also “encourages Parties to align their next nationally determined contributions with long-term low greenhouse gas emission development strategies” (Paragraph 40). Parties also “shall provide information on how the preparation of their nationally determined contributions has been informed by the outcomes of the global stocktake” (Paragraph 169).


Guiding Questions

Use the following guiding questions to reflect and identify the most nationally appropriate and impactful Opportunities within this Route, to explore more deeply:

Were the last NDC targets quantified?Were baselines and reference points established and updated to reflect the latest scientific and socio-economic data? Were established methodologies used to ensure accurate estimation and accounting of GHG emissions and removals?

Did the last NDC implement steps to ensure the accuracy and comprehensiveness of the data used in NDCs, particularly in terms of integration across different governmental levels?

Are structured review processes in place to evaluate and enhance NDCs based on previous implementation cycles and emerging scientific knowledge? Is information from NDC implementation documented, shared, and used to facilitate continuous learning and improvement? Are lessons from previous NDC cycles integrated into current and future Climate Action Plans?

Is the information necessary to track progress made in implementing and achieving NDCs as part of the Enhanced Transparency Framework (ETF) supporting the development of the NDC 3.0? Are the processes aligned?

Is the national framework for engaging with Article 6 instruments designed to supplement rather than replace domestic mitigation efforts, and are the conditions and limits for the use of these instruments set? Are measures in place to ensure transparency and prevent issues like double counting when using Article 6 mechanisms, particularly in relation to corresponding adjustments?

Are national adaptation commitments aligned with global adaptation goals, and do these commitments support the objectives outlined in international agreements such as the Paris Agreement and SDGs? Are systems in place to track the implementation and effectiveness of adaptation measures, and is this tracking integrated with NDC monitoring?



How This Links to Other Routes

The need for technically sound and transparent evidence underpins all aspects of an NDC. Some of the key linkages with other Routes in the NDC 3.0 Navigator are shown below.  

Route: Aligned to the Paris Agreement Temperature Goal

A sound evidence base is critical for prioritizing effective and impactful mitigation actions, understanding future pathways, and tracking implementation. Inventories, projections, targets, and progress towards these are also required under the enhanced transparency framework.

Route: Aligned to Paris Agreement Global Goal on Adaptation

A sound evidence base is critical for prioritizing effective and impactful adaptation actions and understanding the likelihood and severity of future climate impacts. Undertaking vulnerability and risk assessments is a key part of adaptation planning, and monitoring and evaluation processes for tracking progress.

Route: Unlocks Finance

Accessing finance starts with understanding the level of investment needed, and quantifying the costs and benefits of actions. Developing technically sound documents can support the evidence needed to unlock finance for implementation.

Route: Delivers a Just and Equitable Transition

Ensuring a technically sound evidence base for action, includes understanding and quantifying the wider impacts of transitions. This can ensure that the prioritization of actions is equitable and minimizes negative impacts.

Route: Technology and Capacity-Building as Needs and Enablers

Reporting and tracking capacity, technology and finance needs are key aspects of the transparency framework. Building capacity is also critical to ensure knowledge and skills for technically sound NDCs.

Route: Mobilizes All-Of-Government and All-Of-Society

NDCs and transparency processes involve engagement and support across All-of-Government as well as with other actors, including the provision of data for tracking, enhancing the evidence base for action, prioritizing actions, ensuring continuous improvement, and maintaining knowledge.

Support Opportunities

Support is available to countries to apply the learning from the navigator and develop ambitious NDCs 3.0.

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Contribute new guidance, tools and strategies to be reflected in the NDC 3.0.