The role of carbon uptake in understanding oceans' future
Currently, the oceans take up about 25 % of the CO2 emitted annually by human activities. Researchers have made major contributions to our understanding of the oceans' carbon cycle. However, carbon uptake by the oceans is changing, and many questions on the oceanic carbon sink remain unanswered. The EU-funded CARBOCHANGE (Changes in carbon uptake and emissions by oceans in a changing climate) project sought to fill these knowledge gaps. The CARBOCHANGE team used buoys, floats and research vessels such as commercial ships to observe the amount of CO2 uptake. Scientific apparatus was installed on board to provide continuous measurement. A data portal was set up on the project website that makes all accumulated data available to scientists worldwide. Field observations, process studies and modelling were employed to measure the main physical, chemical and biogeochemical processes that further modify CO2 over time. Model systems were devised to help contribute to future climate prediction, and observational data was used to calibrate and enhance current models. Such models were then used to quantify past and present oceanic carbon sinks and sources. Project members also predicted future transformations in ocean carbon cycling regarding ongoing and future CO2 emissions and related climate change. Observations and model results will feed into the Global Earth Observation System of Systems (GEOSS), under the Group on Earth Observations (GEO), and the Global Ocean Observing System (GOOS). CARBOCHANGE has also assisted in preparing and establishing the marine branch of the Integrated Carbon Observation System (ICOS) that provides data on carbon cycle and greenhouse gas in Europe. Synthesis reports and outreach papers targeting policymakers, researchers and the public provide information on how much CO2 the ocean takes up on a regional and a global level and what drives related changes. CARBOCHANGE helped to determine the oceans' quantitative role for the uptake of human-produced CO2 under changing climate conditions. Its efforts provide a solid knowledge base for sustainable climate policies.
Keywords
Carbon uptake, oceans, carbon dioxide, emissions, carbon cycle, changing climate