Global Carbon Budget 2019 Released:

 AOML Contributes Ocean Carbon Observations for the Annual Estimates

Every year the Global Carbon Project publishes an authoritative observation based Global Carbon Budget detailing the annual release of fossil fuel carbon dioxide and the uptake by the terrestrial biosphere and oceans. In 2018 the global carbon emissions were still increasing, but their rate of increase had slowed. Global carbon emissions are set to grow more slowly in 2019, with a decline in coal burning offset by strong growth in natural gas use worldwide. 

Emissions from burning fossil fuels are projected to grow by an average of 0.6 percent this year to reach almost 37 billion tons of carbon dioxide or 10.1 petagrams of carbon. This is down from 1.5 percent in 2017, and 2.1 percent in 2018. 

This lower rate of growth is due to substantial declines in coal use in the European Union and the United States, and slower growth in coal use in China and India compared to recent years. Weaker economic growth has also contributed to this trend. 

Total carbon dioxide emissions from human activities (combustion of fossils and land-use change) are set to reach an estimated 11.8 petagrams of carbon in 2019. The relative contribution of land-use change to the growth rate in total carbon dioxide emissions is larger than that of fossil fuels for 2019, although the data is more uncertain.

NOAA’s Atlantic Oceanographic and Meteorological Laboratory leads the Ship of Opportunity program, comprised of partners in academia and NOAA’s Pacific Marine Environmental Laboratory and Earth System Research Laboratory. It is the largest collector of carbon dioxide measurements from surface seawater globally which are collated together with contributions from researchers worldwide annually in a dataset called the Surface Ocean Carbon Atlas. These data are used to determine the amount of carbon that is absorbed by the ocean, collectively known as the ocean carbon sink.  

The ocean carbon sink shows decadal variations and has increased from a minimum in 2000 of 1.2 petagrams of carbon per year to 2.5 petagrams of carbon per year in 2018. The AOML led consortium has collected ocean carbon data from automated instruments on ships since 2005 and is funded by NOAA’s Ocean Observation and Monitoring Division of the Climate Program Office.  

“Our program has greatly enhanced the quantity and quality of surface CO2 measurements worldwide, leading to a more accurate determination of the ocean carbon sink,” said Denis Pierrot, PhD, the program’s lead investigator at AOML. “It also provides the fundamental data for the Global Carbon Budget and numerous other studies such as global climate models or satellite and sensor validations.”

The land and ocean CO2 sinks combined continued to take up over half of the CO2 emitted to  the atmosphere. The uptake of CO2 by the ocean causes ocean acidification, a decrease in pH that makes ocean water more acidic and also decreases the availability of carbonate ions which are the building blocks for numerous economically valuable species such as corals or shellfish. 

The Global Carbon Project is an international research project within the Future Earth research initiative on global sustainability, and a research partner of the World Climate Research Program. It aims to develop a complete picture of the global carbon cycle, including both its biophysical and human dimensions together with the interactions and feedbacks between them. The Global Carbon Budget 2019 is the 14th edition of the annual update that started in 2006.