The mitigation aspects of the Rulebook include information to facilitate clarity, transparency and understanding of NDCs and accounting for countries’ emissions.

Read an overview below or our deep dive on NDC Mitigation Elements.

The Paris Agreement calls for countries to submit information needed for clarity, transparency and understanding (CTU) of the NDCs. In the Rulebook negotiations on CTU, countries had to decide which information was necessary to provide to ensure the NDCs are clear, transparent and understandable. There were significant transparency gaps in the initial NDCs that made it hard to understand countries’ emissions targets. The initial list of information to be included in the NDCs was not sufficiently detailed for understanding the NDCs, and it was voluntary, so some countries didn’t follow the list. That made it impossible to understand the emissions level inferred by many NDCs, the sectoral and/or greenhouse gas coverage of some of the NDCs, and the assumptions and methodologies underlying many of the NDCs, among other details.

In Paris, countries agreed to develop accounting guidance, based on agreed-upon criteria, to support countries in tracking their NDCs. Accounting of emissions is critical for assessing progress toward and achieving the mitigation components of NDCs, especially when countries decide to cooperate through voluntary market mechanisms (which would involve the transfer of Internationally Transferred Mitigation Outcomes, or ITMOs). Accounting gives countries a clear picture of whether they are on track to achieve their NDCs and can inform any adjustments that may be necessary, such as establishing new mitigation policies.

Key Rulebook Decisions from COP24

The list of information agreed to at COP24 for the Rulebook builds on a similar list approved by Countries at COP20 in Lima, Peru in 2014, but it is much more detailed so it can close the perceived information gaps contained in the initial NDCs. Countries will be required to use this list of CTU information in their NDCs starting with their second NDC, but are strongly encouraged to Explaining the Paris Agreement Rulebook | 9 provide this information as soon as possible, including when communicating or updating NDCs by 2020.

At COP24, countries also adopted accounting guidance on how countries should:

  1. Account for anthropogenic emissions and removals in accordance with the Intergovernmental Panel on Climate Change’s methodologies and metrics;
  2. Ensure methodological consistency, including on baselines — the starting point for comparison — between the communication and implementation of NDCs;
  3. Strive to include all categories of anthropogenic emissions and removals in the NDC in a consistent manner; and
  4. Explain why any categories of anthropogonic emissions or removals are excluded from their NDC.

Read NDC Mitigation Elements Deeper Dive