Global carbon emissions did not increase in 2015 and are projected to rise only slightly in 2016, according to climate scientists.
The projected rise in CO2 emissions of only 0.2% for 2016 comes after a 0.7% rise in 2014 and is a clear break from the rapid emissions growth of 2.3% a year in the decade to 2013, according to the research by the Global Carbon Project, which was published in journal Earth System Science Data.
The researchers said declining coal use in China was the main reason for the slowdown. China, which accounts for 29% of global emissions, saw emissions decline by 0.7% in 2015, compared to growth of more than 5% a year the previous decade.
A further 0.5% reduction is projected for China in 2016, although the researchers warned that there were large uncertainties associated with this estimate.
The study backs up findings published earlier this month by consultancy PwC. It said China’s carbon intensity had declined by 6.4% between 2014 and 2015, with most of the reduction due to falling coal consumption.
The US, which is responsible for around 15% of annual global emissions, also reduced its coal use last year, although oil and gas consumption both increased. Nonetheless, the fall in coal use resulted in a 2.6% decrease in US emissions between 2014 and 2015. The country’s emissions in 2016 are projected to fall by a further 1.7%.
The EU produced about 10% of global emissions a year and the study found that the bloc’s carbon emissions in 2015 increased 1.4%.
Data published by the European Environment Agency earlier this month predicted that almost all member states would achieve their 2020 emissions reduction targets, but warned that the pace of reductions beyond 2020 would be slower, and that the EU was likely to cut emissions by only 26–29% below 1990 levels by 2030, compared to its target of 40%.
However, reforms to the EU emissions trading system (EU ETS) and other policy proposals being discussed in Brussels, including a transport strategy, had not been taken into account in the projects, the agency said.
Professor Corinne Le Quéré, director of the Tyndall Centre at UEA who led the data analysis for the Global Carbon Project, said three years of almost no growth in emissions is unprecedented at a time of strong economic growth.
However, she added: ‘Global emissions now need to decrease rapidly, not just stop growing.’
Despite emissions stabilising since 2014, atmospheric CO2 concentration reached a record high in 2015, and is likely to rise further this year due to weak absorption of carbon by trees and other carbon sinks, according to the Global Carbon Project research.
Le Quéré said: ‘With temperatures soaring in 2015 and 2016, less carbon was absorbed by trees because of the hot and dry conditions related to the El Niño event. Atmospheric CO2 levels have exceeded 400 parts per million and will continue to rise and cause the planet to warm until emissions are cut down to near zero.’
Richard Black, director of the Energy and Climate Intelligence Unit (ECIU), said that the decoupling of emissions and growth was ‘undoubtedly significant’ but warned: ‘Will this trend of decoupling emissions continue? Will US disengagement from the global climate process following the election of Donald Trump lead others to do the same?
‘The politics are suddenly looking much more uncertain, although real-world trends of falling prices and growing use of clean technologies seem set to continue.’