Environment & Energy

Advancing Climate Assessments: 50 Years of Progress and Impact
Program News | August 4, 2025
By Amanda Purcell

The second in a series of retrospectives on National Academies’ reports and activities related to climate science.

As our understanding of climate change grew over the last 50 years, efforts to communicate what is known and the implications for decision making have emerged and evolved hand-in-hand. Climate assessments—conducted by governments, international bodies, and non-governmental organizations—are critical processes for bringing the scientific community together with those who use their findings to produce trusted decision-relevant information.

The National Academies have played pivotal roles in advancing climate assessments. Many of the reports featured in our first retrospective dating back to the 1970s and 1980s could be considered assessments, in that they brought together leading experts to review the literature and summarize what was known in a manner that could inform policy and other decisions. These early reports helped demonstrate the value of regular updates on the state of the science, especially for a rapidly-evolving field that integrates many kinds of knowledge.

Before long, both the international community and the United States initiated major climate assessment efforts. The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 and has worked with the international community to produce six assessment reports. Two years later, the U.S. Congress passed the US Global Change Research Act, which calls for a scientific assessment focused on domestic impacts and trends, 25 and 100 years out.

As these assessment processes, along with similar efforts conducted by some states and cities, became more established, the role of the National Academies shifted to providing a detailed technical review of the draft assessment reports and offering advice on how to improve the assessment processes.

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