Status: this preprint is open for discussion and under review for Geoscientific Model Development (GMD).
AD-MERGE 2.0: An Integrated Assessment of the Nexus Among Energy Transitions, Climate Impacts, and Adaptation Responses
Kamyar Amirmoeini,Olivier Bahn,Kelly de Bruin,Kirsten Everett,Hamed Kouchaki-Penchah,and Pierre-Olivier Pineau
Abstract. This paper presents AD-MERGE 2.0, an enhanced integrated assessment model that evaluates reactive ('flow') and proactive ('stock') adaptation strategies along with climate mitigation policies. The updated model extends AD-MERGE 1.0 through seven enhancements: i) including a more recent base year, ii) increased regional details, iii) refined energy system modeling, iv) inclusion of variable renewable energy, v) direct air carbon capture and storage, vi) recalibrated damage and adaptation estimates, and vii) alignment with the latest Shared Socioeconomic Pathway (SSP2, version 3.0). Next, this study assesses five distinct scenarios using the enhanced AD-MERGE 2.0 framework: a Baseline (no mitigation or damage consideration) and two mitigation pathways, a Reference scenario (current policy-driven mitigation and climate damages), and an Announced Pledges scenario (emissions aligned with national commitments). Each of the mitigation scenarios is studied with and without adaptation. Collective advancements incorporated in the model refine analytical precision in scenario analysis, thus facilitating a more extensive examination of regional heterogeneity, energy system dynamics, technological innovation, and economic vulnerabilities associated with climate impacts. The results underscore critical trade-offs and synergies between adaptation and mitigation strategies, focusing on region-specific policy design and integration of clean energy technologies.
Received: 21 Dec 2025 – Discussion started: 27 Jan 2026
Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this paper. While Copernicus Publications makes every effort to include appropriate place names, the final responsibility lies with the authors. Views expressed in the text are those of the authors and do not necessarily reflect the views of the publisher.
This paper presents AD-MERGE 2.0, an integrated assessment model designed to study emissions reductions and adaptation together, and to capture how decisions on one can change the benefits and costs of the other. Building on earlier versions, and by improving how the model represents both climate policy actions and climate damages, this paper provides new evidence on how regions can combine near-term protection from climate change impacts with long-term transitions toward cleaner energy systems.
This paper presents AD-MERGE 2.0, an integrated assessment model designed to study emissions...
