Driven by rising natural gas and oil consumption, levels of CO₂ are expected to hit 37 billion metric tons this year, according to new estimates from the Global Carbon Project (GCP), an initiative led by Stanford University scientist Rob Jackson.

The findings are outlined in three new papers published in Earth System Science Data, Environmental Research Letters, and Nature Climate Change. Although the rate of emissions growth is slower than in the previous two years, the researchers warn emissions could keep increasing for a decade or more unless energy, transportation and industry policies change significantly across the world.

Jackson and his colleagues estimate that global carbon dioxide emissions from fossil fuel sources—which represent roughly 90% of all emissions from human activities—will grow a projected 0.6% over 2018 emissions. That compares to 2.1% growth a year earlier and 1.5% growth in 2017.

The decline of coal use in the European Union and United States is overshadowed by surging natural gas and oil use around the world, according to the researchers. Per capita emissions in affluent countries remain disproportionately high—a fact that further complicates the picture as developing countries seek greater prosperity through more natural-gas-fueled electricity and gasoline-powered vehicles and air travel.

Emissions cuts in wealthier nations must outpace increases in poorer countries where access to energy is still needed.

—Pierre Friedlingstein, a mathematics professor at the University of Exeter and lead author of the Global Carbon Budget paper in Earth System Science Data

The group found that the U.S., E.U. and China account for more than half of all carbon dioxide emissions globally. While annual emissions are decreasing slowly in many industrialized regions—including the U.S., where they are down a projected 1.7% since last year—they are growing in many countries, including China, where they should rise 2.6% this year.

About 40% of global carbon dioxide emissions were attributable to coal use, 34% from oil, 20% from natural gas, and the remaining 6% from cement production and other sources.

Although still a major factor in global emissions, coal has taken a hit, with global usage down 0.9% for the past year. In 2019, consumption of coal is expected to drop 11% in the U.S.—down 50% from its peak in 2005—displaced by cheaper natural gas, wind and solar power, as well as savings from energy efficiency. Coal use should drop a further 10% in the E.U. In China, which accounts for half of global coal use, growth slowed to 0.8% this year due in part to China’s economic downturn.

Billed by some as a “bridge fuel” away from more pollutive energy sources, natural gas produces significantly fewer carbon dioxide emissions than oil or coal. Because of greater supply and cheaper prices, natural gas usage has surged, with an attendant 2.6% increase in carbon dioxide emissions for 2019. Rising natural gas use now accounts for 60% of fossil emissions growth in recent years.

The researchers warn that hopes for natural gas to be a bridge fuel can only come true with measures, such as carbon capture and storage, to mediate the fuel source’s emissions and a reduction in methane leakage from natural gas infrastructure.

While some wealthier countries have made substantial progress in reducing overall emissions, per capita emissions in these countries remain stubbornly high. Around the world, the average person is responsible for about 4.8 tons of fossil carbon dioxide emissions per year. By comparison, the average person in the United States is responsible for more than three-and-a-half times that amount.

Success stories, such as the E.U., where emissions have been declining about 1% per year are counterbalanced by the story of countries such as China, where per capita carbon dioxide emissions have grown to rival or even exceed those of the E.U.

Strong inequalities exist, particularly in per capita oil use. U.S. oil consumption per person is 16 times greater than in India and six times greater than in China. Vehicle ownership is similarly skewed, with almost one motor vehicle per person in the United States but only one for every 40 people in India and 6 in China. A similar rate of car ownership in China or India as in the United States would put a billion new cars on the road in either country.

To counterbalance increasing emissions, the researchers call for stronger national policies and global commitments to help institute carbon pricing, accelerate energy efficiency improvements, reduce energy consumption, deploy electric vehicles, ramp up carbon capture and storage technologies and replace fossil fuels with renewable sources.

The research received support from the Center for Advanced Study in Behavioral Sciences at Stanford University, the Gordon and Betty Moore Foundation, the Australian Government’s National Environmental Science Programme’s Earth Systems and Climate Change Hub, the European Commission Horizon 2020 project VERIFY, and Future Earth.

Resources

• Global Carbon Budget 2019, by Pierre Friedlingstein, Matthew W. Jones, Michael O’Sullivan, Robbie M. Andrew, Judith Hauck, Glen P. Peters, Wouter Peters, Julia Pongratz, Stephen Sitch, Corinne Le Quéré, Dorothee C. E. Bakker, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Peter Anthoni, Leticia Barbero, Ana Bastos, Vladislav Bastrikov, Meike Becker, Laurent Bopp, Erik Buitenhuis, Naveen Chandra, Frédéric Chevallier, Louise P. Chini, Kim I. Currie, Richard A. Feely, Marion Gehlen, Dennis Gilfillan, Thanos Gkritzalis, Daniel S. Goll, Nicolas Gruber, Sören Gutekunst, Ian Harris, Vanessa Haverd, Richard A. Houghton, George Hurtt, Tatiana Ilyina, Atul K. Jain, Emilie Joetzjer, Jed O. Kaplan, Etsushi Kato, Kees Klein Goldewijk, Jan Ivar Korsbakken, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Andrew Lenton, Sebastian Lienert, Danica Lombardozzi, Gregg Marland, Patrick C. McGuire, Joe R. Melton, Nicolas Metzl, David R. Munro, Julia E. M. S. Nabel, Shin-Ichiro Nakaoka, Craig Neill, Abdirahman M. Omar, Tsuneo Ono, Anna Peregon, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Roland Séférian, Jörg Schwinger, Naomi Smith, Pieter P. Tans, Hanqin Tian, Bronte Tilbrook, Francesco N. Tubiello, Guido R. van der Werf, Andrew J. Wiltshire, and Sonke Zaehle (2019), Earth System Science Data, 11, 1783-1838, doi: 10.5194/essd-11-1783-2019.

• Carbon dioxide emissions continue to grow despite emerging climate policies by G.P. Peters, R.M. Andrew, J.G. Canadell, P. Friedlingstein, R.B. Jackson, JI. Korsbakken, C. Le Quéré, and A. Peregon (2019), Nature Climate Change doi: 10.1038/s41558-019-0659-6.

• Persistent fossil fuel growth threatens the Paris Agreement and planetary health by RB Jackson , P Friedlingstein,RM Andrew, JG Canadell,C Le Quéré and GP Peters (2019), Environmental Research Letters doi: 10.1088/1748-9326/ab57b3.