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Comment Re:IPCC figure (Re:Where are the error bars?) (Score 1) 267

The red numbers are stated to be anthropogenic, and many of them have a +- following them which I view to be a standard deviation. The uncertainties associated to those are noting that the annual fluxes (red numbers) are on the orders of 10's, and the ocean inventories are in the thousands. If you have a hundred years of annual fluxes at 10, it's still two orders of magnitude less than the ocean inventory.

The models don't show how deep ocean temperature changes affect the fluxes, and they can't because they don't have those data yet (the number of unknown seamounts is in the thousands).

Given unknown ocean thermal dynamics, it's easy to see an atmospheric increase. But I don't see demonstrative proof that it's not the ocean belching out more CO2 because of increased surface ocean temperature. In other words, I find it as likely the CO2 is a lagging indicator of temperature rise as CO2 is a leading cause of temperature rise.

Comment Where are the error bars? (Score 1) 267

There is a time-series of global average temperature, but there is not a description of the error. I'd like a full statistical treatment, including the number of measurements varying as a function of time, as well as an assessment of the quality of the measurements (I'm sure the thermometer technology has changed in the last 100 years).

The reason why I ask this is when you peruse Figure 6.1 of the IPCC Carbon and Other Biogeochemical Cycles report, the listed errors of natural carbon sources far exceed those of anthropogenic origin. They are doing quality work there; however, the reporting of their efforts leave a lot to be desired.

Comment Re:The election is a poor barometer of relevance (Score 1) 284

Saying Twitter data are poor is misleading. Twitter would render a popular vote if all tweets were taken in aggregate, and in that case, it would have been correct. Now if they are blocking by state and got it wrong, it's still more of a function of who uses Twitter.

Comment Re:Cost? (Score 5, Insightful) 228

His/her question is good, and the summary is incomplete. It converts CO2 to CH3CH2OH at a yield of about 63%, but what CO2 concentration in the water are they assuming? Average soda concentration is about 0.12-0.15 M (moles per liter) at about 4 bar. That would mean you'd get 0.05 M alcohol (2 carbons per EtOH from one carbon in CO2, 0.5*0.63*0.15), which is 0.05 moles EtOH/55.5 moles water or about 0.08 percent alcohol by volume. That's a lot less than the ethanol conversion you'd get from corn.

It did not mention the catalyst materials cost, nor the materials processing required to make a nanomaterial.

So we'd have energy costs by compressing CO2, then converting it using the catalyst, then there would be ethanol separation costs (with requisite electricity/natural gas from the distillation columns) from water that far exceed normal ethanol separation, and the ethanol would still have about 10% water because it is an azeotrope,so then you'd need another liquid-liquid extraction...

As is the case with the other carbon dioxide conversion schemes, it's really cool chemistry, looks good in summary, but the details render it ineffective for practical use.

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