Until now, the slow weathering of silicate rocks has been considered as the main factor in climate regulation.
Until now, the slow weathering of silicate rocks has been considered as the main factor in climate regulation. In this system, rain takes up carbon dioxide (CO2) from the atmosphere, falls on exposed rocks on land, and slowly dissolves them. When the captured carbon enters the sea together with dissolved calcium from the rocks, it provides the basic material for the construction of mussel shells and limestone reefs, which trap the carbon in the ocean floor for hundreds of millions of years. “When the planet warms, rocks weather faster and absorb more CO2, allowing the Earth to cool down again,” explains Dominik Hülse.
In the past, however, there have also been phases during which the Earth was completely covered by snow and ice. According to the authors, this cannot be explained solely by the slow weathering of silicate rock. Other processes must have been involved during the cooling process.
The missing piece of the puzzle is also linked to carbon storage in the ocean floor. When the CO2 content of the atmosphere increases and the planet warms, more nutrients such as phosphorus make their way into the ocean. The presence of these nutrients stimulates the growth of algae, which take up carbon during photosynthesis. When the algae die, they sink to the sea floor, taking the carbon with them.
Read More: MARUM - Center for Marine Environmental Sciences, University of Bremen
Photo Credit: anncapictures via Pixabay
