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Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

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Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#311
post #206
post #169

CO₂ is a precious and much coveted resource in nature. It's predicted to become all sequestered under ground eventually, on a billion-year timescale (making it quite troublesome for life!). More pressingly, when it comes to plant life RIGHT NOW, we're still dangerously close to CO₂ starvation levels. The current ~400 parts-per-million are a good deal healthier than the ~180 ppm we've had throughout Quaternary (which…

The current vegetation is adapted well to the CO2 levels before industrialisation, that is about 300ppm CO2. The change in CO2-content is actually detrimental to some plants. Furthermore, the quick temperature change is going to wipe out large eco systems. The question isn't, what is the optimal CO2 concentration for single species, but about the health of the eco systems we are living in. We are about to wipe out la…

I actually agree with you.

Perhaps the confusion stems from my too-vague use of "we". Your "we" (understandably) refers to humans, who indeed stand much to lose by dramatic CO₂ swings. At least on a suitably mayfly time scale.

My "we" meant more "life on this planet", without as much anthropomorphic bias. Periods of increased warmth and easy access to carbon — the two are historically highly correlated, though not synonymous — are an overall boon to life, referred to as "warm periods", "climatic optimums", "life explosions", etc. This despite the ecosystem upheavals that accompany such large-scale climatic changes being detrimental to incumbent organisms. No argument there.

Coupled with the polarized political nature of the topic, I suspect this difference in "we" resulted in people reading too much into my comment, if you take the time to re-read it. My stance on short-term human-centric status-quo-preserving actions is probably not that different from yours, although I do find broader perspectives and facts helpful in framing rational discourse.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#312
post #305

Earlier quoted context omitted.

Making your transmission line a lot longer doesn't scale your losses by that much surprisingly. The main transmission losses are at the conversion points and in the utility voltage cabling at the end, having long distance interconnects really only loses a percent or two over having short ones.

That's just a very naive simplification of a huge branch of electrical engineering. To have low power losses in long distances, you use high voltage. The higher the voltage, the bigger (and more expensive) the "conversion points" need to be. Power losses will also be bigger. To simplify greatly, having low-loss transmission lines costs more money, more equipment, more investment, more time. That's why it makes more s…

Your objection has merit, but this discussion seems to be focused on "what should we do going forward". While we currently suck at good & economical long distance transmission, this hardly seems to be based on physical limitations. Thus, if it is a worthy goal, we can & should guide our economies towards mastering that tech and driving prices down, kind of like we did with e.g. solar panels.

I'm especially eager to hear more about developments in / experiences with UHV DC lines, like in this ieee.org article + discussion: https://news.ycombinator.com/item?id=19295838

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#313
post #115

Earlier quoted context omitted.

Where do you live where shade trees are a thing?

Where do you live where shade trees are not a thing? Genuinely curious. I've never known someone that didn't know what they were. I live in Michigan and have four large trees surrounding the house, although we let their branches hang over the house, so 3 or so hours around noon, the house gets no shade.

The fact that you presume people outside the US know what and where "Michigan" is makes me think you don't know much about other countries at all.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#315

Earlier quoted context omitted.

"I can't help but notice the lack of specific examples or explanations of any kind" Because its so simple as saying, "the wind COULD have blown the fukushima fallout southwards over Tokyo instead of relatively promptly into the Pacific." A nuclear accident COULD deliver fallout to a highly populated area that cant be evacuated in time. A nuclear accident COULD generate much more fallout than Fukushima or Chernobyl. H…

> Because its so simple as saying, "the wind COULD have blown the fukushima fallout southwards over Tokyo instead of relatively promptly into the Pacific." A nuclear accident COULD deliver fallout to a highly populated area that cant be evacuated in time. So the thing that actually happened with Chernobyl then, not something significantly worse than that. > re: desalination - fine then, add the cost of desalinating s…

Actually - most desalination is done by reverse osmosis - which is much more efficient than evaporation.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#316
post #305

Earlier quoted context omitted.

Making your transmission line a lot longer doesn't scale your losses by that much surprisingly. The main transmission losses are at the conversion points and in the utility voltage cabling at the end, having long distance interconnects really only loses a percent or two over having short ones.

That's just a very naive simplification of a huge branch of electrical engineering. To have low power losses in long distances, you use high voltage. The higher the voltage, the bigger (and more expensive) the "conversion points" need to be. Power losses will also be bigger. To simplify greatly, having low-loss transmission lines costs more money, more equipment, more investment, more time. That's why it makes more s…

>That's just a very naive simplification of a huge branch of electrical engineering.

Anything I am going to squeeze into a comment on hacker news regarding the subject is likely to be. So are you against the concept of continent wide grids and transmitting power long distance from sparsely populated equatorial desert regions to the more populous temperate ones?

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#317

Earlier quoted context omitted.

A single average fully grown tree can sequester about 88lbs of CO2 per year according to the Center for Urban Forest Research, which is part of the US Forest Service. The average electricity service in the US produces about 1lb of CO2 per kWh, meaning that your solar panel needs to reduce your consumption by only 88 kWh per year below what your shaded house cost would be to be a net positive over a shade tree.

Don't quote me on this but from memory a tree is able to sequester a lot more in the first couple of years than as a fully grown tree. Intuitively that makes sense.

Yes, that is true. The carbon sequestration is greatest when the tree is turning CO2 into more tree (e.g. when it’s growing). This process largely stops as a tree hits maturity, and the CO2 is mostly returned when the tree burns or rots.

I’m making the explicit assumption that a shade tree will probably be fully grown.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#318

Earlier quoted context omitted.

All things considered, clearing a forest to help wean us of natural gas and oil is probably a net positive.

nuclear power is significantly more (space-, energy-, ..) efficient and clean than solar farms https://www.forbes.com/sites/michaelshellenberger/2018/05/23...

I’m pro nuclear power, but I also understand that politically and economically it’s a non starter. At this point in time it’s either solar (or wind) or natural gas. I’ll take the known local maximum over a global maximum that’s not feasible.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#319
post #248

Earlier quoted context omitted.

It can be shown both bottom-up and top-down, but I prefer the bottom-up: Photosynthesis is usually an order of magnitude more efficient than photovoltaics: https://en.wikipedia.org/wiki/Photosynthetic_efficiency ...an individual leaf might be peak out at 3% efficient, but it is operating just a portion of the year (maybe about a third to a half at full performance) and also much light gets reflected, absorbed by bran…

Your first paragraph contradicts the rest, I assume by accident.

Ha, you're correct! And now I'm unable to edit.

Re: Planting 1.2T Trees Could Cancel Out a Decade of CO2 Emissions

#320

Earlier quoted context omitted.

I like how we instinctively characterize prisoners as slaves. Seems like it trivializes actual slavery, but I have been out of school for awhile, so the conventional wisdom is probably different now.

If you don't see labour camps as a form of modern slavery, then I'm genuinely asking you to provide the definition you've learned back at school.

Traditionally, prison labor is considered distinct from slavery for the same reason that prison is considered distinct from kidnapping and forced confinement: that it reflects just punishment for which someone is duly convicted. Whether that actually applies to most people in prison today is certainly up for debate, but to tell you'd mostly need to look at the judicial system (or society at large), not at the work camp.
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