Check out this VERY informative 2003 article by Bruce Conway:
The Chemtrail Smoking Gun - Proof of Global Geoengineering Projects
Authorized by Congress and sponsored by the National Academy of Sciences, a monumental and in-depth study on global warming and possible corrective measures (mitigations) was undertaken in the early 1990s. Represented were senior researchers, faculty, theoreticians, atmospheric scientists, department heads and CEO's from a multitude of prestigious institutions. The Smithsonian, Harvard, General Motors, Cambridge, MIT, Yale, World Resources Institute, National Center for Atmospheric Research, the Secretary General of the United Nations, Oxford, Brookings Institution, Columbia University, Oak Ridge National Laboratory, Carnegie-Mellon University, Princeton University, Brown University, Lawrence Livermore Laboratory, and many more. This colossal study recalls the scope, expense and secrecy of the Manhattan Project, yet the goals and eventual impacts of it are far greater.