An American pledge at global climate talks

The second and final week of United Nations climate change talks in Madrid opened with a dash of optimism from the United States as a broad coalition of states, cities and businesses made a case that it could put a significant dent in planet-warming emissions without federal help.

Delivering the news was Michael R. Bloomberg, the billionaire and former mayor of New York City who is now running for president. Mr. Bloomberg co-founded the coalition, America’s Pledge, along with Gov. Jerry Brown of California. Its purpose is to help the United States stick to the goals of the Paris climate agreement despite President Trump’s plan to abandon the pact.

“The reason I am here in Madrid is really pretty simple,” Mr. Bloomberg said. “I am here because no one from the White House is here.”

A coalition report, issued this week and titled “Accelerating America’s Pledge,” found that, even without federal action, efforts to cut greenhouse gasses by the members of the group could have a significant impact.

Critically, the report found that there’s still time for the United States to hit net-zero emissions by midcentury. A recent United Nations report said countries would need to reach carbon neutrality by 2050 to avoid the worst consequences of climate change.

The pledge authors project that with expanded local action, combined with a comprehensive national strategy that includes clean energy legislation and policies to complete the phaseout of coal, the United States could reduce its emissions 49 percent below 2005 levels by 2030.

Left unsaid in the report, but explicitly noted by Mr. Bloomberg in a touch of electioneering, was that such national action would require an administration that prioritizes climate change.

“Beating climate change won’t require a miracle, it won’t require limitless resources,” Mr. Bloomberg said. “It will require leadership and common sense.”

Under the rules of the Paris Agreement, the United States will remain a party to the accord until Nov. 4, 2020, the day after the presidential election.

By Lisa Friedman