Can we fight global warming with artificial global cooling?

Cecil's Columns/Staff Reports
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There is another, much more efficient form of geoengineering, which isn’t harmful.

Assuming carbondioxide (CO2) in the atmosphere is a major contributor to the present climate change, all we have to do is to remove it.

Can it be done?

We know it can, as the chemical industry is already doing exactly that on a rather large scale, extracting about 120 megaton (120,000,000 ton) of CO2 a year from the atmosphere.

This CO2 is used to produce a range of product, such as glue, fertilizer, lithium batteries, medicine, etc.

Other possible use is artificial diesel produced by catalysis. The process has been known since the 1920’es, e.g., US patent no. 1,746,464, applied 1926, published 1930, and was widely used in germany during WW2. We burn the fuel and extract the CO2 for re-use.

The method used today is mainly catalysis CO2+H2O to CO+H2+O2 followed by the Fischer-Tropschs synthesis, where CO+2H2 is catalyzised to carbonhydrids.
The “pollution”, rest product, from the proces is O2 (pure oxygen) which can be compressed and sold.

Unstable wind energy can be used to remove CO2 from the atmosphere and as the energy source for catalysis. As oppsed to the use of wind energy for electricity in industry and households, it doesn’t matter if wind power is only available e.g. at night or Sunday through Wednesday

The German Bundesforschungsministerium (Federal Ministry of Education and Research) granted 100 million Euro for research in the use of CO2 and improved catalysis processes under the project “Technologien für Nachhaltigkeit und Klimaschutz” (Technologies for sustainability and climate protection). German engineers obviously see possibilities where others see obstacles.

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LINK to column under discussion: Can we fight global warming with artificial global cooling? - The Straight Dope

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One of the results of the mass grounding of all air traffic after 911 was a pronounced warming over the US (over 1 degree Celsius, if I remember). Researchers found this by comparing historical weather data. It seem that the contrails of the countless jetliners daily crossing America cause enough additional cloud formation to cool the earth by reducing the amount of solar energy that reaches the ground. This has been corroborated by other research indicating that the sunlight intensity at ground level (not the output of the Sun) has been decreasing for years.

The irony of this is that global cooling has masked the full extent of the effect of global warming.

I believe this was covered in a PBS program, possibly NOVA

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As I understand it, the OP is not asking about the use of aerosols, such a contrails, to reduce the effects of anthropogenic increases in atmospheric carbon dioxide, but is specifically focused on the removal of carbon from the atmosphere, a process generally referred to as carbon sequestration. Carbon sequestration is certainly a key part of any concerted effort to mitigate global climate change, but I think it’s too much to expect it to carry the load all by itself.

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It’s also mentioned in this column on global dimming.

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Absolutely right on the not-aerosols, but no to carbon sequestration (storing CO2 somewhere).

What the Germans (and a few others) do is they remove CO2 at a rate of (today) 120 GT/year for industrial use and in the future as e.g. diesel fuel, same as it was during WW2.

It will be cheaper than e.g. Kyoto etc. - possibly even make money of it.

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So what is contemplated is carbon removal from the atmosphere, using either chemical or biological processes (i.e., growing plants). Then you would release this carbon back into the atmosphere, with the idea that this release would be in lieu of burning fossil fuels. So there would be mitigation of increasing atmospheric carbon, but it would be far less effective than carbon sequestration. It would also require some sort of subsidy, though presumably a lower subsidy than carbon sequestration would require.

Maybe this is worth consideration in conjunction with other strategies - I certainly wouldn’t rule it out. Tentatively, though, I’m doubtful that it would help all that much.

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On an industrial basis about 120,000,000 metric ton of CO2 is extracted every year from the atmosphere. I wouldn’t call that “contemplate”, it’s actually done.

The method works but is presently too expensive for common use outside specialized industries, which actually make money out of it.

The German Federal Ministry of Education and Research has granted 100 million Euro for research in (mostly) improved - thus cheaper - catalysis processes.

If they succeed we may see the carbon extracted, used as e.g. fuel, then extracted again, reused, extracted, … in a cyclus that may stabilize the atmospheric CO2 level to where we think it should be.

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Can you expand on what is currently being done, and why?