(Jim Lo Scalzo/European Pressphoto Agency)

The Environmental Protection Agency released a report Monday predicting a range of expensive, even deadly consequences if the world’s governments do nothing to combat climate change.

If the world twiddles its thumbs, instead of restraining the rise in average global temperature to no more than 2 degrees Celsius, 12,000 more Americans would die every year from temperature extremes by 2100, and the country’s annual economic toll in road and bridge maintenance, lost labor, water quality degradation, energy use and crop damage would surpass $100 billion, according to the EPA report. Some 35 percent of Hawaiian coral and 34 percent of the nation’s oysters would die off, and hundreds of thousands of acres of cold-water fish habitat would disappear. If, on the other hand, the world keeps average warming to 2 degrees, the United States would avoid all of these consequences.

Here’s the problem: Though several major new international commitments will move the planet in the right direction, the world is almost certainly not going to hit its 2 degree target. An International Energy Agency (IEA) analysis released last week found that governments are still falling far short. The IEA mapped out a path to keeping the world at or below 2 degrees, showing that it’s technically doable at a reasonable cost, but the politics of achieving the required emissions reductions are extremely difficult.

What would the EPA’s figures look like in a world in which humanity misses the 2 degree target but still does a lot more than nothing? It’s unclear; the EPA did not feature results from intermediate warming pathways — in other words, the agency did not publicly game out what’s most likely to happen. The EPA might be wary of giving legitimacy to any warming goal beyond 2 degrees or of making the potential benefits of constraining emissions seem smaller. But an analysis that compares only the best-case and worst-case scenarios, leaving out more realistic ones, provides only a sense of the maximum possible benefits to cutting emissions, not what the country’s climate policies are likely to accomplish.

EPA Administrator Gina McCarthy argued Monday that her agency’s report isn’t supposed to be comprehensive; it’s supposed to give ordinary Americans who care about fisheries or forests or who work outside a sense of what’s at stake for their children and grandchildren. “This future will be personal to them,” she said in an interview with me. “The mistake that people make is to fight the climate deniers,” she elaborated. “The real challenge in a democracy is to get the people who are sitting on the sidelines.”

Yet Americans should have a sense of the benefits of constraining emissions — and the risks of not doing so — even if government policies fail to prevent the world from surpassing the 2 degree threshold. A brief section of the report suggests that the country could still avoid substantial negative consequences even if the world passes the 2 degree mark. Among other things, that sort of finding would help shut down Republicans who criticize climate programs on the grounds that emissions cuts would be expensive yet too small to do much good. McCarthy might not expect to change their minds. But she should be trying to make their arguments less persuasive to those on the sidelines.