Global Carbon Budget - Ocean

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere – the “global carbon budget” – is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change.

The Global Carbon Budget describes data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. These five components are CO2 emissions from fossil fuels and industry, CO2 emissions from land-use change, the growth rate of amospheric CO2 concentration, the ocean carbon sink and the land carbon sink.

Less than half of all CO2 emissions remain in the atmosphere, the other half is taken up in roughly equal amounts by the ocean and by the terrestrial biosphere. Since the start of the industrialization land use emissions and the positive effects of the land sink have approximately balanced. The oceans are therefore the most important net sink for anthropogenic CO2 emissions.

The ocean in the Global Carbon Budget

Less than half of all CO2 emissions remain in the atmosphere, the other half is taken up in roughly equal amounts by the ocean and by the terrestrial biosphere. Since the start of the industrialization land use emissions and the positive effects of the land sink have approximately balanced. The oceans are therefore the most important net sink for anthropogenic CO2 emissions.

Each year, we collect estimates of the ocean carbon sink from global ocean biogeochemistry models (GOBMs) and surface ocean fCO2-observation based data products (fCO2-products). We quality-control and post-process the data and come up with one best estimate of the ocean carbon sink and its uncertainty.

 

Schematic representation of the overall perturbation of the global carbon cycle caused by anthropogenic activities, averaged globally for the decade 2013–2022.