The New York Times’ decision to hire columnist Bret Stephens — who has expressed skepticism about the dangers of climate change — roused the ire of scientists and subscribers who openly expressed their contempt on Twitter. Upon the publication of a column defending the hire, climate scientist Michael E. Mann led a #ShowYourCancellation campaign. The campaign is gaining traction among furious readers following Stephens’ debut column, a controversial op-ed arguing the fairness of skepticism toward climate change.

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Stephens — a former editor at The Wall Street Journal and 2013 Pulitzer Prize winner for commentary — described himself to the Huffington Post as a “climate agnostic,” side-stepping charges that he was indeed a climate change denier. His first column for the paper was promoted with a push notification from the Times that read, "reasonable people can be skeptical about the dangers of climate change." In his column titled “Climate of Complete Certainty,” Stephens wrote,

“Claiming total certainty about the science traduces the spirit of science and creates openings for doubt whenever a climate claim proves wrong. Demanding abrupt and expensive changes in public policy raises fair questions about ideological intentions. Censoriously asserting one’s moral superiority and treating skeptics as imbeciles and deplorables wins few converts.”

Mann, the director of the Earth System Science Center at Pennsylvania State University, took umbrage at the Times’ editorial decision to run the column. But the real impetus to cancel for Mann and others who participated in the #ShowYourCancellation campaign was the Times’ defense of the controversial hire in an earlier April 22 piece titled, “Seeking More Voices, Even if Some Don’t Want to Hear Them.” In it, Public Editor Liz Spayd wrote,

"Stephens’s coronation produced a fiery revolt among readers and left-leaning critics. They rummaged through his columns for proof that he is a climate change denier, a bigot or maybe a misogynist. More complaints came into the public editor’s office than at any time since the election, with many readers threatening to cancel their subscriptions. (I’m told relatively few actually have.) Inside the building, some of Stephens’s future colleagues posted his “greatest hits” on a bulletin board. And a handful of newsroom staffers, most notably columnist Max Fisher and Cairo bureau chief Declan Walsh, have challenged Stephens on Twitter."

Mann responded to the article on Twitter, writing, "The @NYTimes hiring of climate denier didn't lead me to cancel subscription. Public editor's offensive response did."

In response to Spayd’s allegation that few Times readers had actually cancelled their subscriptions, Mann wrote, “Folks, it appears that the @NYTimes wants you to PROVE your subscription cancellation.”

Since Mann spearheaded the hashtag, #ShowYourCancellation has been tweeted hundreds of times, with many users sharing screenshots of their confirmation emails.

The controversial column was published just one day ahead of this weekend's Climate March. Tens of thousands of protesters marched across the nation Saturday, President Donald Trump’s 100th day in office, in protest of his positions on environmental policies.