Then there are those who argue physics is the major factor in ocean CO2 uptake: http://phys.org/news/2012-07-discovery-carbon-southern-ocean.html How about salting the Southern Ocean, increasing surface seawater density and sinking carbon rich water? Possibly less ecologically impactful than iron addition? -Greg
________________________________________ From: [email protected] [[email protected]] On Behalf Of Andrew Lockley [[email protected]] Sent: Sunday, July 29, 2012 9:54 AM To: geoengineering Subject: [geo] Why OIF (Dr. Margaret Leinen, Kevin Whilden, Dan Whaley, K. Russell LaMotte) 2009 http://www.climos.com/pubs/2009/Climos_Why_OIF-2009-03-12.pdf Overview The Fourth Assessment Report of Intergovernmental Panel on Climate Change (IPCC) concluded that “It is extremely likely that human activities have exerted a substantial net warming influence on climate since 1750” [Solomon et al., 2007], and that this “is having a discernible effect on physical and biological systems at the global scale” [Rosenzweig et al., 2007]. Starting with the Kyoto Protocol, efforts to mitigate these effects have focused on reducing carbon emissions. Recent international discussions focused on long term targets of about 60-80% reduction in emissions by the year 2050 with the goal of holding the total warming to 2°C above pre-industrial temperatures to “limit the impacts of climate change and the likelihood of massive irreversible disruptions of the global ecosystem” [CEC, 2007]. However, analyses of the proposed emission reduction frameworks suggest that these targets will be insufficient: e.g., “If a 2.0°C warming is to be avoided [by 2100], direct CO2 capture from the air, together with subsequent sequestration, would eventually have to be introduced in addition to sustained 90% global carbon emissions reductions by 2050”[Weaver et al., 2007]. Furthermore, new observations show that the climate change impacts are already greater than expected and happening more rapidly than predicted [Tin, 2008]. These changes and the potential for abrupt changes due to climate feedbacks suggest that it will be necessary to remove atmospheric CO2 as well as reduce anthropogenic greenhouse gas (GHG) emissions in order to avoid even more serious impacts. It is widely accepted that the terrestrial biological carbon sink can be enhanced to reduce atmospheric CO2 through forestation and agriculture practices. However, the deep ocean is the single largest reservoir of mobile carbon on the planet, and ocean phytoplankton (microscopic algae) are responsible for nearly half the annual CO2 exchange and a majority of all carbon sequestered over geologic time. For decades, researchers have studied how the ocean takes up atmospheric CO2 through the action of phytoplankton that sequester carbon to the deep ocean as they continually bloom, die, and sink (a process call the “biological pump”). A large body of oceanographic research (e.g., [Boyd et al., 2007; Martin and Fitzwater, 1988]) and the geologic record [Winckler et al., 2008] indicate that the availability of iron, a micronutrient essential to photosynthesis in all plants, limits the growth of phytoplankton in large areas of the ocean. Three decades ago, John Martin and Steve Fitzwater proposed the “Iron Hypothesis”, i.e. that the deliberate addition of iron to stimulate phytoplankton growth could mimic the CO2 reduction during glacial maxima measured in ice core samples [Martin and Fitzwater, 1988]. Since 1993, twelve open ocean experiments have demonstrated that ocean iron fertilization (OIF) is one method of increasing phytoplankton biomass and, potentially increasing carbon sequestration. Given the threat posed by rapid climate change and the dominant role of the biologic pump in the Earth’s carbon cycle, it seems important that we determine conclusively whether the purposeful enhancement of oceanic carbon sinks, as well as terrestrial ones, is a possibility that is available to man—and what the impacts of doing so might be. This document discusses the need for expanded research into OIF, highlights the key research questions, and presents some ideas on how this research can be conducted in an effective and environmentally responsible manner. -- 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. -- 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.
