By Mark Keenan
June 19, 2026
For more than a decade, one climate scenario exercised extraordinary influence over public policy, media reporting, corporate planning, and public consciousness.
Most people never heard of it. It was known simply as RCP 8.5.
Yet behind countless headlines predicting climate catastrophe, behind many of the studies cited by activists and politicians, and behind much of the urgency driving climate policy stood this single scenario.