The Climate Change Imperatives

In the United States, transportation has surpassed electric power as the most important driver of emissions. The science dictates that net global emissions from energy must decline to zero in the next few decades to avoid the worst risks of climate change.That simply can’t happen in the United States without rapid cuts in tailpipe emissions.

The Trump administration suggests its move would cause U.S. fuel consumption to increase by about 500,000 barrels of oil per day, an amount many experts consider to be an underestimate. The proposal argues the CO2 impact “perhaps somewhat counter-intuitively, is relatively small.”   Additional emissions would be just a drop in the global bucket, according to the rule, less than one part per billion of extra carbon dioxide in the atmosphere. But in making that estimate, the Trump administration reveals an ominous finding.By the end of this century, it expects the accumulation of CO2 to reach concentrations of nearly 790 parts per billion, nearly doubling what’s there today—and enough to blast far past the goals of the Paris climate treaty.The New York-based research firm Rhodium Group projects that the impact of the auto standards freeze will begin slowly but build substantially over time. By 2025, the increase in annual emissions will range from 16 million to 37 million metric tons, ballooning to 32 million to 114 million metric tons by 2035. At the high end—the expected track if oil prices stay relatively low—that’s equivalent to adding another state the size of New Jersey to the U.S. emissions mix.Dave Cooke, senior vehicles analyst for the Union of Concerned Scientists, calculates that by 2040, the Trump freeze would add a total 2.2 billion metric tons of global warming emissions to the atmosphere. (Total annual U.S. carbon emissions are currently about 5 billion metric tons.)