UNEP.Net -
a global portal to authoritative environmental information based on
themes and regions.
Union of Concerned
Scientists - citizens and scientists for
environmental solutions (Note: On specific issues of which I am
personally very familiar, the Union of Concerned Scientists has provided
a significant amount of technical data on their site.
Unfortunately, some of the technical information is in error and their
conclusions differ markedly from Electric Power Research Institute
studies and reports. It's almost as though they were using the technical
information to further their own agenda.)