Charles A. Dana Professor of Science, Technology, and Society James Fleming will be presenting the Tyndall History of Global Environmental Change Lecture sponsored by the Global Environmental Change Focus Group at the American Geophysical Union annual meeting in New Orleans this December. Fleming’s topic is “Gordian Knots of Prevision: The lessons of history.” The annual Tyndall lecture offers a historical perspective on global environmental change. The lecture is named in honor of 19th-century Irish-born scientist John Tyndall FRS, whose measurements in the mid-century confirmed the significance of the greenhouse effect.