April 2018 (Updated June 2020)*





In September 2016, over 375 members of the U.S. National Academy of Sciences (NAS) signed an Open Letter calling attention to the dangers of human-induced climate change. The letter warned that U.S. withdrawal from the Paris climate accord would have negative consequences for the world’s climate system and for U.S. leadership and credibility.





In the intervening months, these negative consequences have become more obvious. Human-caused climate disruption is leading to suffering and economic loss. Suffering and loss are not future hypotheticals. They are happening now. Despite these serious negative consequences, the present Administration has fulfilled its threat to initiate U.S. withdrawal from the Paris climate accord. The United States is the only nation in the world that has taken this action.





The decision to withdraw is symptomatic of a larger problem: the Trump Administration’s denigration of scientific expertise and harassment of scientists. The dismissal of scientific evidence in policy formulation has affected wide areas of the social, biological, environmental and physical sciences. It has been particularly egregious in climate science. A recent instance of this is the intention of the Administration to assemble a “Red Team/Blue Team” to re-litigate all aspects of climate science. Such an exercise seeks to foster the erroneous impression of deep uncertainty concerning the reality and seriousness of anthropogenically driven climate change.





Scientific evidence and research should be an important component of policymaking. We therefore call on the Federal Government to maintain scientific content on publicly accessible websites, to appoint qualified personnel to positions requiring scientific expertise, to cease censorship and intimidation of Government scientists, and to reverse the decision to withdraw the United States from the Paris Agreement.





____________________________________________________________________

*The initial invitation to NAS members to sign the letter was issued in early 2018. In June 2020, NAS members elected in 2019 and 2020 were also invited to sign the April 2018 statement and are included in the following list of over 1,200 signers.





We will continue to update the list as others sign.



