Study finds shock rise in levels of potent greenhouse gas

Scientists had expected fall in levels of HFC-23 after India and China said they had halted emissions

Efforts to reduce levels of one potent greenhouse gas appear to be failing, according to a study.

Scientists had expected to find a dramatic reduction in levels of the hydrofluorocarbon HFC-23 in the atmosphere after India and China, two of the main sources, reported in 2017 that they had almost completely eliminated emissions.