At the UN Climate Conference in Katowice, Poland, this year’s Global Carbon Budget was released. For the purpose of the budget, researchers estimate the anthropogenic carbon budget for the planet as a whole; this includes the sources (emissions), the carbon sinks on land and in the ocean, and the carbon content of the atmosphere. The report provides the figures for the year 2017 and offers an initial indicator of the general trend for 2018.
As of this year, Dr Judith Hauck from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), is coordinating and analysing the contributions on the ocean carbon sink: she analysed all nine models and data products employed by the international research groups responsible for the oceans, and evaluated their models. In addition, the AWI ran its own model simulation, and AWI oceanographer Dr Mario Hoppema submitted valuable long-term data gathered during Polarstern expeditions, which has been integrated into the global datasets.
“The ocean is the largest carbon reservoir, and contains roughly 45 times as much carbon as the atmosphere and 20 times as much as the land biosphere,” explains AWI researcher Judith Hauck. Yet the ocean responds much more slowly than the carbon reservoirs on land and in the atmosphere, because the ocean depths operate on far longer timescales. In 2017, worldwide carbon emissions amounted to 11.3 ± 1.2 gigatonnes, 22% of which (2.5 ± 0.5 gigatonnes) were absorbed by the oceans. The mean atmospheric carbon dioxide concentration was 405 ppm (parts per million) in 2017, and is expected to reach 407 ppm by the end of 2018.
In the 6 December issue of the journal Nature, Christiana Figueres (for many years, the Executive Secretary of the United Nations Framework Convention on Climate Change – UNFCCC) and her colleagues share their thoughts on the report. According to Figueres: “Global CO2 emissions have to be reduced by 2020 if we want to meet the temperature goals outlined in the Paris Agreement. But this is within our grasp; we have already achieved things that would have been unimaginable only a decade ago.”
The Global Carbon Budget is produced by the Global Carbon Project, a joint initiative of Future Earth and scientific partners of the World Climate Research Programme.
You can find additional information here: http://www.globalcarbonproject.org/