Scientists’ Warning to Humanity: A Second Notice

The “Scientists’ Warning to Humanity: A Second Notice” as an article was published in BioScience and is open access and free to everyone. The support was overwhelming, and we ended up with 15,364 scientist signatories from 184 different countries by the time the article was published.

Please distribute the published scientists’ warning article to others using social media such as Twitter with this link to the article at the BioScience website:

For example, you could simply write:
I signed the #ScientistsWarningtoHumanity and now everyone can help by sharing the following link:

Feel free to use the attached image with your social media communication if you wish. Also, please provide the scientists’ warning article to the leaders of your organization, state, province, or country and any others that you think should know about this second warning to humanity.

Any scientist that did not sign the article before the BioScience publication deadline, is invited to endorse it now after publication by visiting ( Therefore, feel free to invite any of your scientist contacts to join in now by signing the article.

The voice of world scientists is essential in driving forward progress on dealing with climate change and other critical environmental trends. Working together, we can make great progress in preserving the biosphere for the sake of humanity.

Thanks, Bill
William J. Ripple
Distinguished Professor of Ecology
Oregon State University

Dear colleague,
I am pleased to inform you that today, BioScience published three thoughtful reply letters to our November, 2017 “World Scientists’ Warning to Humanity: A Second Notice” as well as our response to those three letters. You can read all four letters for free at these links:

Dror's letter:
Skubala's letter:
Pacheco et al.'s letter:

Ripple et al. response letter “The Role of Scientists’ Warning in Shifting Policy from Growth to Conservation Economy” can be viewed at