Paris, France— According to theInternational Energy Agency(IEA), global energy-related carbon dioxide emissions were flat in 2016, at 32.1 gigatonnes, for the third straight year despite growth in economic activity of 3.1%. The Agency attributes this to the growing use of renewable energy, improvements in energy efficiency, the switch from coal to natural gas as well as structural changes in the global economy. The largest declines in CO2 emissions were experience by the United States and China, two of the world’s largest energy users and emitters, while emissions in Europe were stable, thus offsetting increasing emissions from the rest of the world.

In the Unites States, emissions fell 3% while the economy grew 1.6%. IEA attributes the decline in emissions to the surge in shale gas supplies and renewable energy sources which have displaced coal. Demand for coal was down worldwide, but the decline was particularly sharp in the United States where demand dropped 11%. For the first time, the generation of electricity from natural gas was higher than coal. While the report is optimistic about the positive impact of shale gas on CO2 emissions, it failed to discuss concerns about other potential environment impacts its production (hydraulic fracturing) may have, such as contamination of water supplies.

“These three years of flat emissions in a growing global economy signal an emerging trend and that is certainly a cause for optimism, even if it is too soon to say that global emissions have definitely peaked,” said Dr. Fatih Birol, IEA’s executive director, in its report. “They are also a sign that market dynamics and technological improvements matter. This is especially true in the United States, where abundant shale gas supplies have become a cheap power source.”

Another controversial energy source, nuclear, has also increased. IEA states that the world’s nuclear net capacity is the highest it has been since 1993, with new reactors entering the power grid in China, the United States, South Korea, India, Russia and Pakistan. Of course, renewable energy is an important factor in the decline of CO2 emissions in the world’s greatest emitters. In 2016, according to IEA, renewable energy supplied more than half of the global electricity demand growth, half of which is hydro-electric. For example, emissions declined 1% in China while economic activity increased 6.7%. Given this economic growth, demand for electricity grew 5.4%, two-thirds of which were supplied by renewable energy such as wind and hydro-electric, alongside nuclear.

While these results are positive, there is still a great to deal to be done to further slow the progress of climate change. “Market forces, technology cost reductions, and concerns about climate change and air pollution were the main forces behind this decoupling of emissions and economic growth,” states IEA. “While the pause in emissions growth is positive news to improve air pollution, it is not enough to put the world on a path to keep global temperatures from rising above 2°C. In order to take full advantage of the potential of technology improvements and market forces, consistent, transparent and predictable policies are needed worldwide.”