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Don't know where your data is from? Bayesian modeling for unknown coordinates

christopherkrapu.com

50 pointsckrapu4 comments

Chris, this entry caught my eye: Solving climate change by abusing thermodynamic scaling laws

https://christopherkrapu.com/blog/2024/why-dont-we-just-free...

  In a previous section, I provided a rough number of 6800 kg. biomass harvested per hectare each year. To entirely offset global emissions of carbon dioxide, we would need approximately 40 billion tons sequestered per year; at 6 metric tons per acre, this implies 6 billion hectares of arable land. Unfortunately, we only have 1.4 billion hectares.

Is the 1.4 billion constrained by zones that have summers good for growth and winters that can freeze water?

  I assume that the hemisphere is of sufficient size to accommodate the harvest of one township (approx. 9300 hectares)

Ahh, townships have closely packed houses, schools, pools, etc - not harvests (well, we do harvest small patches of our township land - but that's more a large gardening scale thing).

Here, in one shire of a grain growing region, the central township area is 18 square kilometres (1,800 hectares) while the townsite and surrounding shire district area is ~2,100 square kilometres (210,000 hectares)(~800 sq mi) with an average single farm size of ~ 4,500 hectares (One local farm family I know of own that much land about their house, that much land again elsewhere, and farm much more land than that total they own via leasing and share farming - the 9,300 hectares quoted is more or less mean farming family harvest)

Not much scope here for bulk freezing biomass in winter though, there's rarely ice overnight and never snow here historically.

Still, details aside the roll your own biomass permafrost is an interesting take.

Thanks for taking a look at that article! In short, you're right on the first item; only a fraction of that total arable land actually experiences subfreezing winter temperatures.

Given your word choice, I suspect you hail from Britain or a commonwealth country and your (appropriate) definition of township differs from mine. I should have defined it as "survey township" which is a USA term for a grouping of land parcels six miles tall by six miles wide. Again, the number presented is a ballpark estimate, as though we may not have as many nice villages and hedgerows in the Dakotas and other Plains states, we similarly do not farm every single literal acre--though many act as if we should, animals and people be damned.

It was a fun read, I figured a bit of feedback might be of interest.

I'm having yet another busy day so I'll just belt out a quick response and hope I don't make too many mistakes or present as overly critical via "just making observations" ..

Yep, I'm aware of the PLSS grids and various irregularities caused by incremental expansion - that was one of many parochial land mapping systems across the globe I crawled through in the mid 80s to mid 90s when I was working with ERMapper and related groups tying down older ellipsoids, datums, and projections against the new global WGS84. IIRC the PLSS town plats varied in size (not all are 6x6 mile) and the coverage across the US is incomplete.

Guessing that was likely what you meant by township prompted pointing out it was ambiguous and throwing up some real world (for some local to myself subset of that world) farming dimensions.

Not farming every square inch is a good approach, it's the one taken here.

Onto the freezing of biomass - this is, as I'm sure your aware, more or less peat / tundra permafrost ... and the next worst phase of AGW is anticipated to thawing tundra releasing methane and accelerating the increase in atmospheric insulation.

Not to shit on your notion and bury it to capture the carbon, but that is something to think on - how to really really bury carbon for a least a hundred years in the face of AGW and ideally for a thousand or more.

Doesn't kill the notion, just raises the bar for implementation - as does the matter of estimating resources required to prep, seed, and harvest large N thousands of hectares and more year in year out for decades.

Locally we dig up and ship > billion tonnes of various ores every year which chews through a bit of fuel, energy, and slightly alters the spin of the planet. That's an activity that also has some bearing on the progress of AGW.

Given your current writing on geophysical spatial estimation, you might find papers such as Automatic Analysis of Aeromagnetic Images for Gold Exploration * (nope, not one of mine, I do know the authors) et al of interest as they look to tie together geological structure with mineral expressions.

* https://www.tandfonline.com/doi/pdf/10.1071/ASEG2007ab057

Time permitting I'll circle back, all the best.

As you pointed out, the viable area with a sufficiently cold winter is probably shrinking every year. Perhaps the better solution is the one proposed by Yablonovitch et al in which they suggest using deserts instead, though I think that is about as risky, and also a tremendous risk for fire.

Deep down, I have the gut feeling that in a century's time, people will think we were clinically insane for not trying to stockpile as much carbon as possible in whatever means we have, since it is clearly the foundation for biology, and widespread synthetic biology will use it (and N, and P) by the gigatonne. I really don't see any fundamental physical reason why we won't be growing entire cities made out of wood with the right genetic engineering and sufficient feedstock.

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