William Happer, Emeritus Professor of Physics, Steven Koonin, New York University, Center for Urban Science and Progress, Under Secretary for Science at U.S. Depart. of Energy in President Obama's administration, Richard Lindzen Emeritus Professor, MIT Department of Earth, Atmospheric, and Planetary Sciences: This is a tutorial on man-made global warming, man-made climate change for the U.S. District Court, Northern District of California, San Francisco Division. 1) The climate is always changing. 2) Human influences on the climate are a small (1%) perturbation to natural energy flows. 3) It is not possible to tell how much of the modest recent warming can be ascribed to human influences. 4) There have been no detrimental changes observed in the most salient climate variables and today's projections of future changes are highly uncertain.
