Vehicle ownership in India is expected to grow eightfold over the next 20 years to 235 million, but ownership will still be only one-fifth of the rate in the United States and Australia. If car ownership in India and China were equivalent to that in our two countries, those nations each would have almost a billion more vehicles. That might be fair in a comparative sense, but disastrous for the planet.

If oil consumption is to drop globally, we need to drive fewer miles in more fuel-efficient cars, most of them powered by renewable electricity. Instead, the Trump administration is proposing to roll back vehicle fuel efficiency standards, a dangerous idea that will cost consumers money, kill thousands of Americans from pollution, and increase trade deficits and oil imports. Australia doesn’t set mandatory fuel-efficiency standards for vehicles at all. In terms of greenhouse gas emissions, those policies don’t seem fair for the rest of the world.

Air travel is also growing. The airline industry has experienced a “spectacular expansion” of one billion additional passengers in the last five years. Increased fuel efficiency can’t offset this rapid rise, so carbon dioxide emissions from air travel are growing at more than 5 percent annually. An American is 17 times more likely to fly today than a person in India and five times more likely than someone in China. That hardly seems fair. But air travel is also changing, too. The rising middle class in India, China and elsewhere will inevitably fly more, pushing up carbon dioxide emissions even higher.

There is some good news. Renewables are growing quickly in Australia, generating 19 percent of the country’s electricity in 2018. Coal use in the United States plummeted by half in the last 15 years, replaced by natural gas, renewables and energy efficiency. This remarkable turnabout in the United States has cut carbon dioxide emissions, created hundreds of thousands of jobs and prevented thousands of deaths from air pollution.

But barring a global economic downturn no one seeks, carbon dioxide emissions could be even higher in five years than they are today. If so, growth in global oil and natural gas use will have outpaced stable or slightly declining emissions from coal use.

This is moving in exactly the wrong direction. For the world to meet the goal of keeping the increase in global warming to 2.7 degrees Fahrenheit from preindustrial days, global greenhouse gas emissions must be zero before 2050, and earlier for advanced economies like ours. We want desperately to believe that is still possible.

So it hardly seems fair that Australia’s fossil fuel carbon dioxide emissions have increased over the past four years. Or that, while emissions in the United States have decreased, they have done so at a rate slower than for many peer nations in Europe.

The rest of the world knows what’s unfair, and right now, they’re looking at us.

Rob Jackson is an earth scientist at Stanford University and is the chair of the Global Carbon Project, where Pep Canadell, a research scientist at CSIRO Oceans and Atmosphere in Australia, is executive director. They and their colleagues have just published new research on global carbon emissions in the journals Earth System Science Data, Environmental Research Letters and Nature Climate Change.

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