This video, from 2009, explains why the National Academies will release four reports on climate change, three of them next Wednesday.
NAS explains it this way at their website:
As part of its most comprehensive assessment to date, the National Research Council – the operating arm of the National Academy of Sciences and National Academy of Engineering – will release three new reports examining how the nation can combat the effects of global warming. One focuses on the science to better understand climate change, and the others review options for limiting the magnitude of and adapting to the impacts of global warming. The reports are part of a congressionally requested suite of studies known as America’s Climate Choices.
Millard Fillmore's Bathtub 