Uncertainty about the pledges made by almost 200 countries in the landmark climate deal means the world could fail to mitigate runaway global warming, according to a report by six scientists published Tuesday in the journal Nature Communication.
“In many cases the actions described in these pledges are ambiguous or imprecise,” wrote Joeri Rojelj, the lead author of the paper titled “Understanding the Origin of Paris Agreement Emission Uncertainties.” The scientists urged countries to implement a “robust process that keeps track of where emissions are heading.”
While U.S. President Donald Trump expressed willingness to negotiate a new version of Paris the agreement, the steps urged in the study are unlikely to gain traction in Washington. Trump derided the agreement’s framework of voluntary emission cuts as being unfair to American workers. The scientific study wants the accord strengthened by imposing even more accountability, Bloomberg reported.
To keep temperature rises well below 2 degrees Celsius (3.6 degrees Fahrenheit), the scientists argue that countries need to streamline and remove uncertainties from pledges called "nationally determined contributions,” or NDCs.
“Some pledges focus on improving ‘emissions intensity,’ meaning reducing the emissions per dollar of economic output, but assumptions about socioeconomic growth are often implicit or unknown,” said Rojelj, who advises the United Nations and researches at the International Institute for Applied Systems Analysis outside of Vienna.
“Other countries focus on absolute emissions reductions, which are simpler to understand, or propose renewable energy targets, which can be expressed in different ways,” he said. “Questions also remain about how much land-use-related climate mitigation will contribute, such as reducing deforestation or preserving forests.”
Countries will need to improve their reporting by 2030 or risk having to increase emission reduction targets by factors of four to 25 thereafter, according to the report.