http://www.grida.no/climate/ipcc_tar/wg3/176.htm
"In principle, only ~10^5t of such mesh structures are required to achieve the benchmark 1% increase in albedo." http://www.ucalgary.ca/~keith/papers/26.Keith.2000.GeoengineeringHistoryandProspect.e.pdf "Teller et al (8) note that a scattering system at the L1 point need only deflect light through the small angle required for it to miss the earth, about 0.01 rad as compared to 1 rad for scatterers in near earth orbit or in the stratosphere. For appropriately designed scattering systems, such as the metal mesh described above, the reduced angular deflection requirement allows the mass of the system to decrease by the same ratio. Thus, while a shield at the L1 point requires roughly the same area as a near-earth shield, its mass can be 102 times smaller. Teller et al estimate the required mass at 10^3 tonnes." To answer your question: Why not just reduce the emissions of greenhouse gases? If that costs $500 billion per year to achieve the same effect, and the alternative is $50 billion, I'd have a fairly straightforward answer. And how about the notion that some nations, say China and India, might just refuse to participate in greenhouse gas reductions, with a complete and utter unwillingness not to burn their coal? It surely is worthwhile investigating the possibilities in depth. What harm would a bit of research do? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. 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/globalchange -~----------~----~----~----~------~----~------~--~---
