Economists are not engaged enough with the IPCC

Climate change presents complex challenges requiring insights from various disciplines, including economics. This paper investigates the limited involvement of economists in the Intergovernmental Panel on Climate Change (IPCC), focusing on Working Group 2 (WGII) which addresses impacts and adaptation. The author posits that while the physical science aspects of climate change are well-established, the challenges of adaptation and mitigation are inherently social science problems, requiring a significant economic contribution. The paper frames the underrepresentation as both a supply-side problem (lack of economist interest in climate change) and a demand-side problem (lack of IPCC interest in including economists). The paper will analyze these aspects and explore the potential for future collaboration.

The paper reviews the historical representation of economists in IPCC ARs. While AR1 primarily involved natural scientists, AR2 and AR3 saw a relative increase in economists. However, this trend reversed in AR4 and continued to decline in AR6, particularly within WGII where economists constituted only 4% of Coordinating Lead Authors and 6% of all authors. This contrasts with the higher representation in WGIII (mitigation). The paper also notes that participating economists are often not from mainstream academic economics departments, and tend to publish in climate change journals instead of economics journals. The existing literature suggests a dominance of natural science perspectives in the IPCC, and a relative underrepresentation of economic perspectives, despite their crucial role in understanding the socio-economic impacts of climate change.

The paper employs a qualitative analysis of the composition of authors and cited literature in IPCC ARs, particularly AR6. It examines the representation of economists in WGII and WGIII based on data on coordinating lead authors and all authors. The author analyzes the publication records and affiliations of identified economist authors in AR6 WGII, using metrics like citation counts, journal affiliations, and employment in economics departments. The analysis also considers the types of economic research and their compatibility with the IPCC's needs, classifying economic research into three categories: theory, empirical causal inference, and structural modelling. The paper argues that the emphasis on mathematical formalization, generalizability in theory, and rigorous causal identification in empirical research may restrict economists' contributions to climate change literature. This approach does not readily allow the context-specific and often qualitative nature of climate change research, particularly in areas like impact assessment and adaptation. The paper further discusses the role of Integrated Assessment Models (IAMs) and their limitations in estimating the economic costs of climate change.

The key findings highlight a significant underrepresentation of economists in the IPCC AR6, especially in WGII, which focuses on impacts and adaptation. Economists constituted only a small percentage of authors, and those participating often lacked conventional credentials within mainstream economics departments. The analysis of economist authors in AR6 WGII reveals that many lack experience in traditional economics institutions or publications in highly-ranked economics journals. The paper notes that a large portion of the literature cited in the IPCC reports comes from natural sciences and engineering, with economics contributing a small fraction. Furthermore, the paper identifies a mismatch between the methods favored in mainstream economics research and the types of research needed to address climate change challenges. Mainstream economics research often emphasizes mathematical formalization, generalizability, and rigorous causal identification, which may limit the applicability to complex issues such as climate change impacts, which are often context-specific and multifaceted. The paper also criticizes the prevalent use of Integrated Assessment Models (IAMs) in climate economics, pointing out their limitations and underestimation of the economic costs of climate change. Finally, the paper discusses the limited acceptance of climate-related economics publications in top-tier economics journals, despite an increase in research output in the field.

The findings suggest that the limited involvement of economists in the IPCC is a consequence of both supply and demand-side factors. The constraints inherent in mainstream economic research methodologies hinder the production of the types of analyses needed to address climate change effectively. Simultaneously, the existing dominance of natural scientists in the IPCC and skepticism toward existing economic models may influence the IPCC's demand for economists. The scarcity of economists specializing in climate change and the limited incentives for publishing climate-related research in prestigious economics journals further contribute to this issue. The lack of representation of economists in the IPCC process likely limits the incorporation of essential economic insights into climate policy and decision-making.

The paper concludes that increased involvement of economists in the IPCC is crucial for addressing climate change effectively. Overcoming this issue requires changes on both the supply and demand sides. Economists need to adapt their research methods to better suit the context-specific and often qualitative nature of climate change challenges, and mainstream economics needs to embrace and reward climate-focused research. The IPCC needs to actively recruit economists and foster a more inclusive and interdisciplinary approach to research. Future research could focus on developing more robust economic models that address the limitations of existing IAMs and exploring incentives to encourage more economists to participate in IPCC assessments.

The paper primarily relies on qualitative analysis of author composition and citation patterns in IPCC reports. The selection process of IPCC authors is opaque, limiting a quantitative analysis of potential biases. The categorization of economists may not capture the nuances of interdisciplinary research. The paper's focus on WGII may not fully represent the situation in other working groups. Finally, the paper primarily examines the situation from a supply and demand perspective, neglecting the potential for broader political and institutional constraints.