From AR5 to AR6: exploring research advancement in climate change based on scientific evidence from IPCC WGI reports

Laying in the policy-science interface, Intergovernmental Panel on Climate Change (IPCC) plays a vital role in providing scientific evidence that leads to climate actions and solutions, because IPCC assessment reports have been designed to be policy-relevant and policy-neutral since its beginning around early 1990s. Comparing references in reports contributed by IPCC Working Group I (AR5 v. AR6) using scientometrics methods, we attempt to explore the research advancement that support physical science basis of climate change in the latest assessment cycle. Our analysis indicates more up-to-date researches have joined as scientific evidence in the new assessment, with wider distribution in publishing region, strengthening collaboration across nations and richer diversity in disciplinary structure. Relatively, recent studies considering human system have received greater attention, while early researches on ecological indicators of climate change are valued enduringly as they are still cited frequently in the new report. Further investigation finds that researches of extreme events have gained much attention in the new assessment cycle, and the unification of terms could potentially lead to more effective and efficient climate debates among scientists, policymakers and the general public.