The efficacy of enhancing carbonate weathering for carbon dioxide sequestration ...
Enhanced weathering is a geoengineering strategy aiming to increase continental weathering rates, thereby increasing the delivery of atmospheric carbon (as HCO3-) to the oceans. Most enhanced weathering studies focus on the capacity of silicate rocks (e.g., basalt) and minerals (e.g., olivine, Mg 2...
| Main Authors: | , |
|---|---|
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Frontiers Media SA
2022
|
| Subjects: | |
| Online Access: | https://dx.doi.org/10.17863/cam.87869 https://www.repository.cam.ac.uk/handle/1810/340432 |
| Summary: | Enhanced weathering is a geoengineering strategy aiming to increase continental weathering rates, thereby increasing the delivery of atmospheric carbon (as HCO3-) to the oceans. Most enhanced weathering studies focus on the capacity of silicate rocks (e.g., basalt) and minerals (e.g., olivine, Mg 2 SiO 4 , or wollastonite CaSiO 3 ) to remove atmospheric CO 2 . However, carbonate minerals (e.g., calcite, CaCO 3 ) could provide an additional, rapid way to increase HCO3- export to the oceans. Recent studies suggest that 0.84 Gt C yr −1 could be removed from the atmosphere through the enhanced dissolution of calcite in soils, provided carbonic acid is the main dissolution agent. What is not clear is whether atmospheric CO 2 dissolved in soils can be transported by rivers, which typically have lower [pCO 2 ], to the oceans. This difference in calcite solubility between soils (where weathering occurs) and rivers (where HCO3- is transported) may lead to large amounts of secondary carbonate formation during ... |
|---|