MARRAKECH, Morocco — Worldwide emissions of heat-trapping carbon dioxide have flattened out in the past three years, a new study showed Monday, raising hopes that the world is nearing a turning point in the fight against climate change.

However, the authors of the study cautioned it’s unclear whether the slowdown in CO2 emissions, mainly caused by declining coal use in China, is a permanent trend or a temporary blip.

“It is far too early to proclaim we have reached a peak,” said co-author Glen Peters, a senior researcher at the Center for International Climate and Environmental Research in Oslo.

The study, published in the journal Earth System Science Data, says global CO2 emissions from fossil fuels and industry is projected to grow by just 0.2 percent this year.

That would mean emissions have leveled off at about 36 billion metric tons in the past three years even though the world economy has expanded, suggesting the historical bonds between economic gains and emissions growth may have been severed.

“This could be the turning point we have hoped for,” said David Ray, a professor of carbon management at the University of Edinburgh, who was not involved with the study. “To tackle climate change those bonds must be broken and here we have the first signs that they are at least starting to loosen.”

The authors of the study attributed the slowdown mainly to a decrease in Chinese coal consumption since 2012. Coal is a major source of CO2 emissions.

Chinese emissions were down 0.7 percent in 2015 and are projected to fall 0.5 percent in 2016, the researchers said, though noting that Chinese energy statistics have been plagued by inconsistencies.