Joe Biden got a D-minus on a climate change report card ranking Democratic presidential candidates released Thursday by the liberal environmental group Greenpeace. Update: Greenpeace revised its grade for Biden to “B” in June of 2019, citing “his commitments to investing in renewable energy and achieving net zero emissions by 2050.”

Biden, the Democratic front runner, has yet to release a detailed plan on how he will combat climate change. But the scorecard evaluated 19 candidates on their commitments to ending the use of fossil fuels and support for environmental policies based on statements, legislative records and published plans. Some candidates also responded to a 29-question survey from the environmental group.

“If he wants to translate his front-runner status in the polls to actual leadership on climate, we need him to come out with a bold, concrete plan in line with the scale of the crisis we’re facing,” said Janet Redman, climate campaign director for Greenpeace USA.

The Biden campaign didn’t immediately respond to a request for comment. During a campaign swing in New Hampshire earlier this month, the candidate called for an “environmental revolution,” though he has yet join many of his Democratic campaign opponents in signing onto the Green New Deal.

“We have an existential threat,” he said. “If we don’t act quickly we’re going to basically lose everything we have.”

The report comes as the issue of climate change has emerged as a marquee issue for Democrats on the 2020 campaign trail following the release of New York Representative Alexandria Ocasio-Cortez’s ambitious plan to fight climate change called “The Green New Deal.” Support for that initiative was part of the Greenpeace score.

Washington Governor Jay Inslee, who is basing his run for president on the need to fight climate change, received the highest score, an A-minus, on the report card. The next highest were Vermont Senator Bernie Sanders and New Jersey Senator Cory Booker, who each received a B-plus from the group.

Former Colorado Governor John Hickenlooper, who has been supportive of his state’s abundant oil and gas industry, also received a D-minus. The report gave both GOP presidential candidates Bill Weld and President Donald Trump an F.

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