To limit climate change, by 2030 the world must install the equivalent of the current largest solar park — every day. The rate of energy efficiency improvements will have to triple the rate of the past two decades. And by 2035, the sale of the internal combustion engine needs to be a thing of the past. Those are some of the items in a new International Energy Agency report titled “Net Zero by 2050: A Roadmap for the Global Energy Sector,” which warns that the pathway to net zero is “achievable” but “narrow.”

The report hails the rapid growth in the number of countries that have pledged to achieve net zero emissions; those pledges now cover about 70 percent of global emissions of carbon dioxide. China has pledged to reach net zero emissions by 2060. But the report warns that in many cases there is nothing backing up the pledges. Most of them “are not yet underpinned by near-term policies and measures,” the report said. Even if successfully fulfilled, the pledges to date would still fail to cover 22 billion tons of carbon dioxide emissions worldwide in 2050.

With international leaders set to convene in Glasgow in six months to outline climate measures, the “commitments made to date fall far short of what is required by that pathway,” the IEA report said.

But the IEA notes that overhauling the planet’s climate is a tremendous economic opportunity. According to the agency, energy investment would surge to $5 trillion by 2030, adding 0.4 percentage points to annual global growth. Fourteen million jobs would be created. And by 2030, global GDP could be 4 percent higher than it would be if the world economy continued on its current path.

In the report, the IEA has tried to spell out the measures needed to reach net zero by 2050 and to provide a “road map” that would outline interim steps along the way. The IEA road map is aimed at keeping climate change to 1.5 degrees Celsius or 2.7 degrees Fahrenheit — slightly more ambitious than the 2 degree Celsius target set in the Paris climate accord in December 2015.