Actually this option does not look too bad on first sight - low cost, low tech, so that's a good start, and the chemistry looks right too. Biggest problem is the delay of approx 100y before the results come through, if I read the paper right. That's a long time for us to have to wait. Also if we change our minds, its a long lead time for reversal.
Go for Mg silicate weathering on land / intertidal zones, and the CO2 drawdown is immediate, operating on a decadal time scale. Re the kinetics of Mg silicate, they are unfavourable if carried out in a chemistry lab. Carried out in nature and enhanced by activity of fungi, bacteria, roots, digestive systems of worms and higher animals, etc, it's a great deal faster - the biospheric enhancement factor speeds it up by several orders of magnitude. Oliver. On Sep 26, 4:09 pm, "Rau, Greg" <[email protected]> wrote: > And to round out the options, let’s not forget Harvey’s > limestone-rain-in-the-ocean > method:http://iod.ucsd.edu/courses/sio278/documents/harvey_08_co2_mitigation... > While billed as (eventual) air capture, I view this as ocean CO2 capture – > bomb upwelling areas with limestone to consume the excess CO2(aq) prior to > degassing to air. Don’t forget that the ocean emits in gross >300 GT CO2/yr. > If we can cut that by 1% it would have a huge effect on air CO2. No? > Humbly, > Greg -- 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.
