20.10.19~20.10.25 Up to 0.9 gigatonnes more CO2 absorbed by oceans each year than scientists thought


Scientists have been underestimating the amount of carbon our oceans absorb from the atmosphere each year. Previous estimates indicated that about a quarter of the emissions caused by human activity were drawn into the ocean. In other words, more than 2 gigatonnes of CO2 per year. Researchers supported by the EU-funded 4C and RINGO projects have found that the annual uptake is in fact much higher, exceeding previous estimates by up to 0.9 gigatonnes. These results and the methods used to reach them are explained in a paper published in the journal ‘Nature Communications.’

To generate more accurate estimates, the researchers developed a procedure to recalculate the SOCAT data using 1992 to 2018 measurements of the ocean temperature a few millimetres below the surface. The temperature was mainly obtained from satellite infrared observations. Based on the corrected figures, the net annual uptake of carbon into the oceans is between 0.8 and 0.9 gigatonnes more than previously believed – an amount that is sometimes double the uncorrected figures. “These results are consistent with independent estimates of the size of the oceanic carbon sink – those based on global ocean surveys by research ships,” stated co-author Jamie Shutler, also of the University of Exeter, in the same article. “Now that these two separate estimates of the size of the carbon dioxide ocean sink agree pretty well, we can view and use their results with greater confidence, and trust that they are most likely giving us an accurate picture of what is going on.” This study forms part of the 4C (Climate-Carbon Interactions in the Current Century) project’s efforts to quantify the main processes regulating the carbon-climate system. It also furthers the RINGO (Readiness of ICOS for Necessities of integrated Global Observations) project’s goal to generate accurate data on carbon fluxes between the atmosphere, the Earth and our oceans. RINGO concludes at the end of 2020 and 4C in 2023. For more information, please see: 4C project websiteRINGO project website

An excerpt form https://cordis.europa.eu/article/id/422529-up-to-0-9-gigatonnes-more-co2-absorbed-by-oceans-each-year-than-scientists-thought