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Additional material supporting the article "Target atmospheric CO2: Where should humanity aim?", Comment: 27 pages, 21 figures; final version accepted by Open Science Atmospheric Journal; main article separately submitted to arXiv as "Target atmospheric CO2: Where should humanity aim?", arxiv:0804.1126

Many palaeoclimate studies have quantified pre-anthropogenic climate change to calculate climate sensitivity (equilibrium temperature change in response to radiative forcing change), but a lack of consistent methodologies produces a wide range of estimates and hinders comparability of results. Here we present a stricter approach, to improve intercomparison of palaeoclimate sensitivity estimates in a manner compatible with equilibrium projections for future climate change. Over the past 65 million years, this reveals a climate sensitivity (in K W−1 m2) of 0.3-1.9 or 0.6-1.3 at 95% or 68% probability, respectively. The latter implies a warming of 2.2-4.8 K per doubling of atmospheric CO2, which agrees with IPCC estimates.

Various types of pumps and pump drives were evaluated to determine the lightest weight system for supplying propellants to a planetary orbit insertion rocket engine. From these analyses four candidate propellant feed systems were identified. Systems Nos. 1 and 2 were both battery powered (lithium-thionyl-chloride or silver-zinc) motor driven pumps. System 3 was a monopropellant gas generator powered turbopump. System 4 was a bipropellant gas generator powered turbopump. Parameters considered were pump break horsepower, weight, reliability, transient response and system stability. Figures of merit were established and the ranking of the candidate systems was determined. Conceptual designs were prepared for typical motor driven pumps and turbopump configurations for a 1000 lbf thrust rocket engine.