RealClimate is a commentary site (blog) on climatology. The site's contributors include climate scientists whose goal is to provide a response to developing stories and a context they feel is sometimes missing in mainstream commentary on climate science and climate change. The forum is moderated, and is restricted to scientific topics to avoid discussion of political or economic implications of the science. RealClimate was launched on 10 December 2004 by nine climate scientists.

Michael Evan Mann is an American climatologist and geophysicist. He is the director of the Center for Science, Sustainability & the Media at the University of Pennsylvania. Mann has contributed to the scientific understanding of historic climate change based on the temperature record of the past thousand years. He has pioneered techniques to find patterns in past climate change and to isolate climate signals from noisy data.