Paris Conundrum: How to Know How Much Carbon Is Being Emitted?

As climate negotiators consider rules for verifying commitments under the Paris Agreement, they will have to confront a difficult truth:  There currently is no reliably accurate way to measure total global emissions or how much CO2 is coming from individual nations. 

Will we be able to verify the Paris climate accord?  Right now science is not up to the task, say the people in charge of assessing our annual emissions of CO2.  There is, they say, no sure way of independently verifying whether national governments are telling the truth about their own emissions or of knowing by how much global anthropogenic emissions are actually increasing.

And that is distinctly alarming, given the contradiction between reports that anthropogenic emissions have stopped rising and atmospheric measurements showing that annual increases in CO2 levels have reached record levels.

Climate negotiators are committed to concluding a rule book for implementing the Paris Agreement at their next annual conference, in Katowice, Poland, in December.  Central to that will be an agreed plan to monitor, report, and verify the pledges made by almost 200 countries.

It will require, as Edinburgh University’s Paul Palmer has put it, “looking for small, gradual reductions of large numbers; so we need to make sure we get the numbers right.”  But the science of accurate carbon accounting is in its infancy. And while international efforts are aimed at helping developing nations gear up to the task, it is far from clear that just having more carbon counters can fix the gaps in the data.

Even developed nations with lots of climate scientists do not deliver demonstrably reliable emission statistics, according to Sourish Basu, a research scientist at the U.S. National Oceanic and Atmospheric Administration (NOAA).  He reported in 2016 that national CO2 emissions are only known “to within 5-10 percent for most developed countries,” while the error bars on declarations by developing countries are “larger by unknown amounts.”

Until now, national figures have been taken largely on trust.  But with the rubber about to hit the road on climate accounting, the emissions declarations of countries such as China, the world’s largest emitter, are being increasingly questioned.  The potential for climate conflicts over who is putting what up their power station chimneys and out their car and truck exhaust pipes seems set to grow.

Accurate carbon counting has two practical goals for the Paris Agreement.  The first is to establish the current trends and future trajectories of global emissions, so we can chart whether the world is on target for restricting global warming to less than 2 degrees Celsius.  The second is to determine whether individual nations are meeting their Paris promises.

Good verifiable data is essential to allow signatories of the agreement to assess progress and agree on new targets, which they are pledged to do every five years.  But right now, even verifying total global emissions is out of reach, according to some researchers.

Read more at Paris Conundrum:  How to Know How Much Carbon Is Being Emitted?