http://m.iopscience.iop.org/1748-9326/8/1/014009
Environmental Research Letters Volume 8Number 1 Peter Köhler et al 2013 Environ. Res. Lett. 8014009 doi:10.1088/1748-9326/8/1/014009 Geoengineering impact of open ocean dissolution of olivine on atmospheric CO2, surface ocean pH and marine biology OPEN ACCESS Peter Köhler, Jesse F Abrams1, Christoph Völker, Judith Hauck and Dieter A Wolf-Gladrow Abstract Ongoing global warming induced by anthropogenic emissions has opened the debate as to whether geoengineering is a 'quick fix' option. Here we analyse the intended and unintended effects of one specific geoengineering approach, which is enhanced weathering via the open ocean dissolution of the silicate-containing mineral olivine. This approach would not only reduce atmospheric CO2 and oppose surface ocean acidification, but would also impact on marine biology. If dissolved in the surface ocean, olivine sequesters 0.28 g carbon per g of olivine dissolved, similar to land-based enhanced weathering. Silicic acid input, a byproduct of the olivine dissolution, alters marine biology because silicate is in certain areas the limiting nutrient for diatoms. As a consequence, our model predicts a shift in phytoplankton species composition towards diatoms, altering the biological carbon pumps. Enhanced olivine dissolution, both on land and in the ocean, therefore needs to be considered as ocean fertilization. From dissolution kinetics we calculate that only olivine particles with a grain size of the order of 1 μm sink slowly enough to enable a nearly complete dissolution. The energy consumption for grinding to this small size might reduce the carbon sequestration efficiency by ~30%. Dates Issue 1 (March 2013) Received 22 October 2012, accepted for publication 7 January 2013 Published 21 January 2013 -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
