China's Revised Carbon Metrics Cut Reported Emissions Growth in Half, Analysis Finds
By Colleen Howe
BEIJING, May 27 (Reuters) — China has quietly altered the way it measures carbon emissions, effectively erasing about half of the growth in emissions it previously reported between 2020 and 2025, according to a new analysis published Tuesday by climate researchers.
The shift, described as “dramatic” by Lauri Myllyvirta, lead analyst at the Centre for Research on Energy and Clean Air (CREA), means that the world’s largest emitter of carbon dioxide now shows a significantly flatter emissions trajectory over the current five-year plan period.
When China’s updated carbon intensity figures are converted into absolute emissions, they imply that the country’s CO₂ output rose 7% from 2020 to 2025. That compares with a 14% increase implied by the previous methodology, according to the CREA analysis, which was conducted in partnership with Carbon Brief.
The change effectively lowers the estimated annual emissions by roughly 700 million metric tons — an amount equal to the yearly emissions of Germany or South Korea.
Analysts say the revision could make it easier for Beijing to meet its 2030 climate targets, even if absolute emissions continue to climb. Under the United Nations framework, China has pledged to reduce its carbon intensity — the amount of CO₂ emitted per unit of economic output — by 65% from 2005 levels by 2030.
The researchers found that starting with the current five-year plan, China began excluding so-called non-energy uses of fossil fuels — such as oil and coal consumed in chemical production, which has risen in recent years — from its carbon intensity calculations. At the same time, the country began including industrial process emissions tied to sectors like cement manufacturing, though output there has declined amid a prolonged property sector slump.
The net effect of those methodological changes is to make reported emissions appear lower, the report notes.
Another potential factor: data gaps in monitoring. The researchers suggest that emissions from the chemicals industry may have been undercounted, possibly as a result of pressure to meet annual reporting deadlines.
“The change in the definition of carbon intensity has the effect of weakening China’s climate targets and introducing more uncertainty into tracking progress,” the report said.
China’s state planner, the National Development and Reform Commission, and the Ministry of Ecology and Environment did not immediately respond to faxed requests for comment.
China does not publicly detail its methodology for calculating carbon intensity. The researchers were able to reproduce the revised figures by cross-referencing GDP data with estimated emissions from fossil fuels.
The timing of the disclosure is notable as the United States, under the current administration, has begun stepping back from its own climate ambitions. That shift has focused international attention on China’s accounting practices and the credibility of its emissions pledges.
“While under the UN climate framework China is free to use any definition it wants to meet its own nationally determined climate pledges, retrospective changes to methodology or inconsistent accounting could erode the value of the country’s commitments,” the report concludes.
(Reporting by Colleen Howe; Editing by Kate Mayberry)