A Diachronic Analysis of Word Frequency in IPCC Reports: Exploring Shifts in Climate Change Discourse

This study analyzes the word frequencies in the Intergovernmental Panel on Climate Change reports to uncover scientific concerns and linguistic trends in climate change discourse. Focusing on four “Summary for Policymakers” reports from 2001 to 2023, it investigates how the language used by climate scientists reflects shifting priorities in climate change issues. Using a corpus-based approach, it analyzes word frequencies, noting the prominence of words related to climate change, such as climate, change, global, warming, adaptation, and mitigation. The findings suggest that while earlier reports predominantly used the term climate change, there has been a recent shift toward the more urgent term global warming. Additionally, action-oriented terms like just and net zero have entered the most recent report, indicating a focus on immediate solutions. The analysis also exhibits a growing use of scientific confidence description which underscores the increasing certainty in climate science. This linguistic shift reflects changing scientific priorities in the global policy response of climate risks. The study contributes to both climate science and linguistics by exploring how evolving word choices influence public understanding in climate change issues.