A deep dive into greenhouse gas inventories: An inside look at the UNFCCC-GIR-CASTT training

From 14 July to 1 August 2025, an intensive training workshop on greenhouse gas (GHG) inventories was organized by the secretariat of the United Nations Framework Convention on Climate Change (UNFCCC) and Greenhouse Gas Inventory & Research Center of Korea (GIR) in Seoul.

This highly technical training covered topics such as: reporting and review under the UNFCCC and Paris Agreement; GHG inventory compilation and the use of the IPCC Inventory Software; GHG estimation methodologies for different sectors; and GHG Projections. It also provided a valuable opportunity for experts from around the world to share experiences and lessons learned in preparing their GHG inventories.

Support from the FAO CBIT-AFOLU+ project

The FAO CBIT-AFOLU+ project provided financial support to four national experts working on fulfilling their countries’ climate change reporting requirements to attend the training. The following participants gave insights into how the training would help build both individual and institutional capacity, and address some challenges in their countries:

• Ms Tamara Legnazzi, Compiler on Argentina's team for their first Biennial transparency report (BTR) and also designated leader of development for their National inventory report (NIR).
• Ms Ilenia Donoso, Programme specialist at the Ministry of the Environment as part of the Voluntary Certification System, HuellaChile
• Ms Andrea Navarrete Alfonzo, Director of greenhouse gas and compound emissions inventories and forecasts at the National Institute of Ecology and Climate Change of Mexico
• Mr Johnethy Roy Morris, Consultant at the Vanuatu Department of Climate Change for the compilation of the data for the national GHG inventory.

Furthermore, Mr Iordanis Tzamtzis, FAO climate change expert from the CBIT-AFOLU+ Team, provided training on the 2006 IPCC Guidelines for the Agriculture and Land use, Land-use change and Forestry (LULUCF) sectors, complemented by hands-on sessions using the IPCC Inventory Software.

Improved technical capacity and learning from other countries’ experiences

Participants mentioned that the training helped them:

• improve their skills in compiling national GHG inventories and generating GHG projections;
• better understand reporting related to different sectors such as the energy, Industrial Processes and Product Use (IPPU) and waste sectors, but especially the AFOLU sector; and
• improve their knowledge of the IPCC Inventory software and the benefits of using it.

Participants also appreciated the opportunity to network with their peers and learn how they overcame common challenges in compiling GHG inventories.

Addressing countries’ climate change reporting challenges

Although many challenges are country-specific, some common gaps included the need for:

• Better systems for managing data over the long-term.
• More coordination across sectors and institutions involved in climate change reporting.
• Increased expertise in specific sectors such as transport, waste and AFOLU.
• Training on cross-cutting issues related to the Common reporting tables (CRTs) including the new calculations, key notations and documentation boxes.
• Including more relevant GHG emission sources for each country – for example, wetlands (in Mexico). 

Benefits of the training

Participants noted that both the technical side of the training, as well as the chance to learn from peers in other countries, were equally valuable.

“I think the most important piece of learning is a stronger ability for the systemic analysis of the national GHG inventory and the mindset to develop comprehensive plans to improve the inventory and the report, together with the networking experience.”

- Ms Tamara Legnazzi (Argentina)

“The most valuable thing I learned in the program was how to review national inventories from other countries as part of a Technical Expert Review (TER) process, as well as having a basic knowledge of the IPCC Inventory Software. I also greatly enjoyed connecting with professionals from other countries.”

- Ms Ilenia Donoso (Chile)

“As an AFOLU expert, this training was very helpful in gaining a deeper understanding of the processes that generate emissions in sectors such as IPPU, energy and waste; as well as the key aspects for estimating their emissions. I also found it valuable to learn about how the IPCC Inventory Software works, and to learn that the updates it has undergone make it easier to comply with the Enhanced Transparency Framework (ETF) reporting requirements.

One of the most enriching parts of the training was the opportunity to exchange experiences with colleagues from different countries. It was extremely insightful to share the needs and barriers we face when preparing inventories, as well as to learn from approaches that can be adopted across contexts.”

-  Ms Andrea Navarrete Alfonzo (Mexico)