[extropy-chat] Global warming news

[Damien Sullivan]

On Fri, Mar 24, 2006 at 06:25:45PM -0800, "Hal Finney" wrote:

> Air is well mixed over the relevant time frames, from what I understand.
> But your point is well taken.  The question is, how much carbon needs
> to be removed from the air?  Running some numbers it looks like a
> daunting task.

Skipping numbers for a conceptual view: we need to remove about as much carbon
as we've put in over the past century.  Daunting, yet should be doable -- we
put it there in the first place!  Of course, extracting 380 ppm CO2 is
entropically harder than burning dense hydrocarbons.  We'd need nukes and/or
solar to replace fossil fuels, then more nukes/solar to drive CO2 removal,
replacing the energy infrastructure twice over.  And don't forget the methane.

At least, if we did it industrio-chemically.  Irrigating the drylands like
Spike says might be a lot easier, though I don't think diverting rivers will
cut it -- other life was depending on those rivers, which tend to be overly
diverted or managed anyway (the *Colorado*?  Source of water for LA and
Phoenix?) Massive desalination seems the way to go, though I don't know about
the brines problem.  Fortunately reverse osmosis seems a lot more energy
efficient than simple evaporation.

To borrow from Mark Atwood, I see the Great Plains covered in genetically
modified hemp, pissing off the left and right alike...

> 10 pounds of carbon per day is about 5 kilograms, and at 12 grams per
> mole that is 400 moles.  Times 393.5 kJ that is approximately 160 MJ!

Might be right.  Simpler for me is that a kilogram of oil is 40 MJ; one of my
basic botec facts.

-xx- Damien X-)