Supporting the development of greenhouse gas emissions and removals projections in Latin America and beyond

GHG emission and removal projections are essential tools guiding climate action at both national and global scales, helping to track progress toward the goals of the Paris Agreement. By using historical data, economic trends, and policy assumptions, countries can build realistic emission trajectories for 2030, 2040, and beyond, identifying the most appropriate ways to achieve climate neutrality.

Seeking to scale up greenhouse gas emission and removal projections, IIASA scientists collaborated with colleagues from UNEP to prepare a comprehensive document, which would help integrating the development of projections into the climate policy cycle.

“Estimating future GHG emissions and removals behavior is a fundamental tool of climate policy,” explains Zuelclady Araujo Gutierrez, lead author of the study and researcher in the Integrated Biosphere Futures Research Group of the IIASA Biodiversity and Natural Resources Program. “Our guide presents a series of recommendations for countries to develop consistent, transparent, and robust projections that serve both to update their Nationally Determined Contributions (NDCs) and to outline long-term development strategies (LTS).”

The guide introduces a nine-step cycle for GHG projection development covering scope definition, data collection, tool selection, calibration, uncertainty analysis, quality control, documentation, and continuous improvement. The document outlines three methodological “grades” for developing projections of varying complexity – from simple spreadsheet-based linear regressions to complex integrated assessment models (IAMs) – allowing countries to tailor approaches to their context.

Although the guide is applicable globally, it places particular emphasis on supporting Latin American and Caribbean countries, many of which face capacity challenges but are committed to ambitious climate goals. The document provides an overview of how projections have been part of the climate policy of some countries in the region, including Argentina, Belize, Colombia, Chile, Mexico, and Uruguay. Furthermore, it explores in greater detail two case studies, Argentina and Chile, and details how projection methodologies have been integrated into national LTS and NDC processes in those two countries.

The guide builds on IIASA’s experience with integrated modeling tools such as GLOBIOM, GAINS, and MESSAGEix, while also recognizing the value of less complex tools like LEAP and MITICA.

The full publication is available for download here in English and Spanish.