If rising greenhouse gas emissions sometimes seem like an inevitable byproduct of modern prosperity, new data suggests that need not be the case.

Last year the world economy grew without an associated increase in the rate of global carbon emissions – the heat-trapping gases scientists say are primarily responsible for a warming planet. That kind of carbon-stable expansion of wealth hasn’t happened in four decades, says the Paris-based International Energy Agency (IEA), which released the data in March.

Broadly speaking, it’s a sign that all the money and effort nations and businesses have poured into cleaner energy systems – expanding renewable power, curtailing carbon-heavy coal, and improving overall energy efficiency – is having an effect.

Experts are quick to caution that much more must be done to keep rising temperatures within a widely agreed safe range. The world continues to emit vast amounts of carbon dioxide. Projections still show levels rising throughout the century. Even if CO 2 emissions dropped to zero overnight, lingering greenhouse gas concentrations would continue to warm the planet for centuries, according to the United Nations Intergovernmental Panel on Climate Change.

Still, evidence of cleaner economic growth is exciting for those who work on a challenge as immense and protracted as global climate change. The news is well timed, too: Nations are developing their climate plans ahead of international negotiations in Paris this December. Progress on emissions – however slight – shows world leaders that “this is a doable thing that the world can work on together,” says Jennifer Morgan, global director of the climate program at the World Resources Institute, a climate research organization based in Washington.

“This should give them confidence that they can meet their emissions targets and still grow their economies,” Ms. Morgan says.

The world emitted 32.3 billion metric tons of energy-related CO 2 last year – effectively unchanged from 2013, according to IEA. An emissions flatlining or decline has happened only three times in the 40 years of IEA records – the early 1980s, 1992, and 2009 – and all were associated with global economic contraction. In contrast, the global economy grew by 3 percent in 2014.

There are two primary reasons for the global pause in emissions growth, experts say. The first is that emissions have effectively flatlined in the industrialized world – namely the United States and Europe. Decades of incremental improvements in car and appliance efficiency have added up to major savings in energy consumption. Meanwhile, the energy being consumed has become cleaner as utilities switch from carbon-heavy coal to cleaner-burning natural gas and carbon-free sources like wind and solar. The second reason: The country everyone expects to dominate carbon emissions for decades to come may have begun to counter that expectation.

“Maybe the single most encouraging factor here is that the [climate] policies that China has put in place are in fact beginning to bend its emissions curve downward,” says Elliot Diringer, executive vice president of the Center for Climate and Energy Solutions, a nonprofit in Arlington, Va.

Between 2005 and 2010, China cut its carbon intensity (CO 2 emissions divided by gross domestic product) by 21 percent, and, last November, it unveiled expanded climate targets in a joint agreement with the US. Over the next 15 years, China plans to double the share of non-fossil fuels in primary energy consumption to around 20 percent. If all goes according to plan, China’s carbon emissions will peak in 2030 or even sooner.

The most obvious impetus for such a shift to cleaner energy is China’s high-profile urban-smog problem. But China’s leaders also want to be at the cutting edge of an emerging clean-energy industry.

“Efforts to clean up the air and reduce greenhouse gas emissions in China are consistent with intentions to implement broader economic reforms,” says Valerie Karplus, director of the Tsinghua-MIT China Energy and Climate Project. That includes “transitioning to a higher-value-added, more knowledge-based economy, and reducing emphasis on export-led heavy industry as a key driver of economic growth.”

Get the Monitor Stories you care about delivered to your inbox. By signing up, you agree to our Privacy Policy

If China can do it, the hope, at least, is that other rapidly growing regions will also modernize more cleanly than the West did.

“I think it’s significant,” Morgan says of last year’s emissions flatlining, “but we shouldn’t relax.”