CORVALLIS, Ore. — In November of 1992, more than 1,500 scientists put their signatures on an extraordinary document titled “World Scientists’ Warning to Humanity,” imploring global leaders to save the planet from environmental disaster. Now, 25 years later, more than 15,000 scientists have signed an updated version of that historic plea, saying “time is running out.” “World Scientists’ Warning to Humanity: A Second Notice,” published Monday in the international journal BioScience, charts the progress — or lack thereof — on the issues highlighted in the original document and renews the call for urgent action. Lead author William J.