evidence: Fig. 5 shows where the CO2 comes from (in the upper half you see the sources – fossil carbon and deforestation) and where it ends up (in the lower half you sees the sinks), in the course of time. It ends up in comparably large parts in air, oceans and forests. The share absorbed by the land ecosystems varies greatly from year to year, depending on whether there were widespread droughts, for example, or whether it was a good growth year for the forests. That is why the annual CO2 increase in the atmosphere also varies greatly each year, and this short-term variation is not mainly caused by variations in our emissions (so a record CO2 increase in the atmosphere in an El Niño year does not mean that human emissions have surged in that year). [...] As already mentioned and shown in Figs. 4 and 5, the oceans absorb net CO2 and do not release any. The resulting increase in CO2 in the upper ocean is documented and mapped in detail by countless ship surveys and known up to a residual uncertainty of + – 20% . This is, in itself, a very serious problem because it leads to the acidification of the oceans, since CO2 forms carbonic acid in water. The observed CO2 increase in the world ocean disproves another popular #fakenews piece of the "climate skeptics": namely that the CO2 increase in the atmosphere might have been caused by the outgassing of CO2 from the ocean as a result of the warming. No serious scientist believes this.