New York Times Public Editor Liz Spayd, the paper's internal critic of its work, criticized new conservative columnist Bret Stephens on Wednesday for his first op-ed that cast doubt on the "certitude" about climate change.

Spayd wrote on Wednesday that it was "pugnacious" to write on a "flammable" subject for his introductory piece. She said Stephens was "minimizing the serious risk of climate change."

Stephens' column, published late last week, suggested that there may be danger in saying the case is closed on climate science, and compared it to the widely believed "data" that said Hillary Clinton would win the 2016 election.

He allowed that the Earth probably is warming and that human activity is a significant cause. But Stephens, a former Wall Street Journal columnist and intense critic of President Trump, said the truth does not "entirely" lie on one side of the debate.

The column led to a cascade of comments and letters to the Times from offended readers. Spayd's critique of Stephens attempted to answer some of them and get his version of the story, a rare move for the paper's public editor. The person in that position usually analyzes the Times' news coverage rather than its columnists.

"For Stephens to win over new readers he'll need to make a strategic pivot, from preaching to a choir of Journal conservatives to winning over a Times audience of suspicious liberals," wrote Spayd. "Being steadfastly anti-Trump, as Stephens is, might count for something, but whatever trust was built up among Journal readers may be back on empty here. Showing some patience and respect for the new audience could start filling the tank."