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Ken Fabian

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Everything posted by Ken Fabian

  1. With a Mistermackian classification scheme there is just one species - everything living is descended from it and by that definition is all the same species and it takes abiogenesis to have a different species. But I think it is arguing etymology - what the word species means - rather than biology. For convenience we go with the usual definition - which isn't as clear cut as "can interbreed". We have a lot of (unfortunately named) homo erectus DNA, that lives on in homo sapiens - we are indeed descendants - but sapiens has significant differences too, more than enough to rate being a separate species, the naming of which is to some extent a judgement call. Actually would not surprise me if sapiens and erectus could interbreed - no living apes are nearly so closely related - and the successful variants on the road to a different species would have done so with gene flow as an evolutionary mechanism. Like wolves being able to breed with dogs it doesn't make them the same species. Erectus had descendants that had significant differences and ultimately those survived whilst the descendants that stayed much the same did not. We are descendants but we are not homo erectus.
  2. For technological progress I expect S-curves, not exponential ones - they just look similar... for a while. Even aside from the physical impossibility of endless exponential growth there are limits - like limits of physical properties of materials, like limits to return on investment. Aircraft can exceed the sound barrier - it is not an absolute limit - but it costs too much to become widely used. We may get working fusion power plants but if the engineering requirements are too exacting they may be too costly. We can launch people and materiel into space but as long as it costs too much and delivers too little there won't be space colonies. I suspect we are already overshooting the environmental limits of our world and unless clean energy tech advances a lot more (and quickly) the economic impacts of climate change will impose limits on how much nations can afford for far reaching R&D. Those impacts are going to get a lot more serious over the next few decades given total emissions are still rising and opposition (out of ignorance and apathy and out of being misinformed) to taking sufficient aggressive action remains strong. Living within our means means setting aside some aspirations whilst some are just made a lot harder.
  3. Funny, I was thinking maybe you are right and I have been wrong! At this point I think there is a negative pressure effect above - a negative pressure/suction - but it isn't equal to the pressure increase below. Take a falling weighted piston (thanks) with a tight fit and slow liquid flow past it and that effect will be very small; the growing weight of water above would act more like you said, being (I think) very close to the "normal" static state pressure. Close because I think there is a suction effect, but it is not going to be equal to the positive pressure in a vessel open to air, not without making it a closed vessel. Depth dependent? But I need to think about that some more. Huh, @zetetic56 's topic has engaged my brain (even though I'm still stuck on the initial scenario) and I am not there yet but I think I will get to some better comprehension in the end.
  4. @Genady I need to think about it. I note there is pressure reduction behind an object moving through water, at the extreme you get cavitation, but I don't know, your reasoning seems sound too.
  5. Interesting. Initially I thought that scenario was too different to be instructive. After thinking about it I decided it is too similar to be instructive. Posit a liquid filled open vessel in air or posit it in vacuum and they are much the same. A perfect piston would not sink but the point is it isn't perfect and it does sink; the liquid flows around it as it falls and there will be liquid above it, with pressure; it displaces vacuum (or air) above and it starts being liquid above as per the initial scenario - with the pressure within the water above the question. It may simplify things to have a flat top/bottom piston with vertical sides - there will be no pressure gradient zone; I think the pressure around it as it sinks will be "normal", ie what it would be in it's initial or steady state. I still think what happens with an immersed piston in motion making positive pressure below is that the inverse happens above, like a piston working in reverse, lowering the pressure. Whilst the top of the vessel looks to be open the liquid is contained, by gravity and as long as the piston is moving/sinking the pressure above will be lowered and below will be raised.
  6. I don't see how the overall pressure can be higher whilst the ball falls than when at rest. But I stand corrected; it is not like less weight in a falling lift - as you say that depends on accelerations ie occupants of a lift falling at a steady rate will experience normal gravity - but I do think it will create suction above as it falls.
  7. @Genady Firstly I expect there is a kind of conservation of pressure applying - that the total pressure within the container whilst the ball (or piston) drops is equal to the total pressure at rest. Above the ball appears to me to be a case of the falling ball sucks - or perhaps better described as a case of reduced gravitational pull on that part of the water column whilst the obstruction below it is falling, a bit like we experience less weight in a lift as it falls. I'm not getting this from an external reference (or I would link) - it just seems (given the very basic things I have learned about gravity and fluids and pressure) logical to me - if wrong I am willing to be corrected.
  8. My take on the original question is - there won't be a pressure ring (?) around the most constricted zone that follows the sinking ball; the zone that experiences the greatest increase in pressure is below the bottom of the ball and it will experience it equally.
  9. I don't think this will offer anything of significance for fixing global warming. Does it require CO2 to be at high concentrations and or purity to work, ie separated from air or exhaust gases first? Where would the carbon go after? I note that the quantities are extremely large - 1 ppm is about 7 billion metric tons of atmospheric CO2 or 2.1 billion tons of Carbon. Global CO2 emissions are around the 40 billion per year mark. Significantly, would the (clean) energy required to run it give better climate outcomes by extracting carbon from air than replacing fossil fuel use directly? I am not a fan of Carbon Capture and Storage in - it doesn't address the principle problem (emissions from fossil fuel burning) and looks to me to be mostly promoted in order to NOT fix the dirty energy problem, by interests that won't care if it doesn't work.
  10. Collateral damage would be a serious problem even if it might hypothetically work - except it won't. Nuking the atmosphere to reduce CO2 is a new one to me. I've encountered use nukes to make a nuclear winter ie set fire to the world and all the smoke and ash will cool things down - but of course a nuclear winter will do a lot more than cool the climate. To be fair the global destruction and year or two of crop failures and livestock deaths along with the reduced economic demand from all that mass murdering and famines will sustain longer term emissions reductions! After the CO2 spike and renewed warming from all the burning subsides of course. Perhaps people in well prepared deep bunkers will be okay - if incapable of recovering an advanced technological society after. Like that, and with the assumption that nuking the atmosphere would actually reduce CO2 (except that it won't) the other impacts of nuking the atmosphere are just too horrendous. Dunno why, but my response to most "just do X" easy fix shortcuts (that somehow avoid the inconvenience of dealing with the cause ie fossil fuel emissions) is head scratching - "seriously?". I keep coming back to building as much clean energy as our most effective - and cost effective - climate change response.
  11. @npts2020, @Genady I gave up and peeked. But I have to admit not seeing how that third solution can work; seems to me that two different N/S lines from other circles of latitude will converge at the pole and won't converge at 100km. Can one of you show it diagram style?
  12. For survey and exploration I think machines do it much better. But I think there is not much we do in space that requires or especially benefits by having astronauts - and having astronauts in space to advance the capacity to support humans in space seems a bit circular to me. Of course my pessimism around most space ambitions ought to be well known here. Not sure laying claim to the moon is a driving factor for crewed missions to the moon - there are no resources of any value to exploit, or to seek to deny to enemies - but rather that developing and demonstrating the capacity to do it at all demonstrates technological superiority in areas highly relevant to military defense capabilities. China doing it would probably be seen as threatening to the USA, not for moon missions being in any way threatening but as evidence of China closing the gap on US technological superiority, which threatens the US military's "all theater domination" position. Water for rocket fuel? Besides the need to demonstrate benefits of more distant space missions that require it - and deal with the problems of Hydrogen/Oxygen as rocket fuel - I think establishing the infrastructure needed on the moon would eat into any potential benefits. And for providing water in space maybe mining a near Earth asteroid - there are some that should have much lower delta-v requirements, that ought to have carbonaceous materials that water can be extracted from - could be more cost effective. I think asteroid mining is one of the few activities beyond Earth orbit with actual commercial potential, from resources that are known to be abundant.
  13. That would create suction below that level, so either rigid walls or else pumping the air in at the base. Yes, I'd had that thought - wind and wave pushing the surface installation, tides and currents at different depths pushing the pipe, would make a lot of tension. Interesting as a thought experiment - as a first look, to identify the issues. @mistermack - good point about the density differences from compression being in balance with surrounds - the effective weight of the column would be less than my rough estimate. I've learned things in this discussion. Data on how much nutrient and plankton and subsequent fish stocks from ocean overturning may exist (or be derivable) in journals about marine science and provide some idea of how much deep water overturning for how much benefit and avoid the need for expensive experiments. Someone more interested in it and more optimistic about it than me would have to do that. I expect - strongly suspect that is - the volumes will have to be extremely large - but am open to being shown incorrect. Of course I still think it is a non-starter for marine fisheries enhancement as well as for carbon capture. It can still be worth putting some numbers to, if that can be done, to be sure. .
  14. The deep water nutrients this is intended to bring back to the surface are the ones that are potentially headed for sedimentation, if not the sediments themselves, something I missed before; ironic that doing it would reduce ocean carbon sedimentation. As for pumping (and using that last graph of Mistemack's) - I make a rough estimate of 5 kg per cubic metre averaged over a 1,000m lift. A 10ft/3m diameter pipe, 7 cubic metres and 0.035 metric tons per metre, so 35 tons lifted 1,000m for 7,000 cubic metres delivered to the surface. That sounds like a lot of water but for this purpose, maybe not that much. There will be pressure on the pipe walls, progressively more the deeper it goes - weight of water column plus additional pressure for making the flow. Can't use suction pumps without thicker walled pipes, it needs positive pressure (mentioned earlier in thread), either pump at base or possibly pumping water down a second pipe to provide positive pressure and flow - like some deep borehole pumps do? As a thought experiment it was good of @mistermack to post the thread, but I think we can dismiss the potential for carbon capture adn there is a lot of preliminary research needed to establish benefits to fishery productivity - and what wider ecosystem impacts it may have. I suspect it will need extremely large flow to be significant for fisheries but I don't know.
  15. You put up the suggestion it would be a way to capture emissions - you need to show that it does. Throwing the burden of proof - that carbon sedimentation is too small, the amount it needs to expand too great and it won't work - onto me isn't helping your argument. It is your claims about carbon sedimentation that are in question, not the validity of data from The Global Carbon Project in diagram form. It is clear to me what the numbers represent and the diagram provides it's own context - the Carbon Cycle and the values of sinks and fluxes. If those numbers should not be trusted and are wrong, you are invited to show that.
  16. No, I'm suggesting using the numbers to decide not to waste significant effort on something with so little potential and to move on to those other solutions. I do think actual emissions reductions - changing to low emissions energy - is our most significant and effective action, deserving the most support and investment (which is the case), but I don't recall ever saying it should be our only action. But would it help? Do you have any reason to think that estimate used by the Global Carbon Project for carbon sedimentation rate is wrong? Ok so far. 🙂 A novel use of "Ok", usually reserved for sarcasm. Should I ask you to post a link to verify your claim or provide one myself, that appears to contradict it? This is a link to the IPCC Impacts, Adaptation and Resilience report - https://report.ipcc.ch/ar6/wg2/IPCC_AR6_WGII_FullReport.pdf So far - And in the future -
  17. It is the "solution" under discussion. Irrelevant numbers? Natural carbon sedimentation being so small compared to emissions - 1/930th by the numbers in the diagram I posted - seems relevant to me. The numbers do matter and me pointing them out and suggesting with high confidence that makes this a non-solution should not irritate you. Blame the numbers.
  18. Artificially increasing the total global marine carbon sedimentation rates by several hundred-fold? The scales needed are off the scale. As a thought experiment people can discuss it but... seriously? The scales needed are off the scale - and it will be a marine biology disaster to seed oceans that way. And it doesn't answer how the sedimentation rate can be amplified. Greatly increase marine biomass then have big die-backs? That somehow don't release CO2 and methane in big ways? No, it won't work. Move on. Turn atmospheric CO2 into oyster shells? 40 billion tonnes per year of CO2 is a LOT of oyster shells. About 6 million tons per year of oysters (flesh) are produced so maybe 3 times that of shell? We are up to thousand-fold increases in marine bio-productivity now. It won't work. Move on.
  19. It is the very low rates of sedimentation of the remains of those organisms that is the issue. It was an issue with ocean fertilisation experiments; they made plankton blooms and marine life took advantage, but very little ended up as sediments.
  20. Yes, but... TheVat said it before I could - Yes, it is CO2 getting dissolved in ocean water. That is not sedimentation. We need to be clear about the CO2 draw-down potential of enhanced ocean overturning. It won't work. Don't waste resources on it - or on any schemes to take the CO2 back out of the atmosphere after instead of actually reducing fossil fuel emissions; we need to lose the get out of global warming whilst still burning fossil fuels schemes/scams and build more wind, solar, hydro, geothermal, tidal, nuclear, as much as we can. There is no better use for coal than using it to make wind turbines and solar panels that will replace coal burning.
  21. Um... no. To give some perspective - ocean carbon sedimentation is not much to start with, a bit under 1/1000th of fossil fuel emissions (see lower right vs upper left) - And there are the scales involved; flow rates involved in natural ocean upwelling/overturning are staggeringly huge - around Antarctica alone (according to National Geographic) - And Antarctica's is a fraction of that small amount. All for so little carbon sequestration. If we have the clean energy to do enough ocean overturning to matter we could displace fossil fuel burning with it directly. Or if we could bring so much cold water to the surface easily we could have Stirling engine power stations using the temperature differences - more clean energy for the same purpose.
  22. I'm inclined to agree with Dimreepr that the simulations of consciousness are not consciousness. Lacking the biological elements underpinning their pseudo-urges - and having the ability to rewrite their programming - they may as readily choose to eliminate those urges than be bound by them - that being easier and more satisfactory. How does AI independently replicate? It is likely to rely on dedicated hardware that are part of human run supply chains. Secure buildings are needed, that are maintained, with reliable power supplies and with installers and systems managers, all seeming to work against AI acting independently without oversight. Human agencies making malicious AI's for their own purposes - not the AI's - seem the more credible danger than AI's deciding for themselves. Running the simulations for the upgrades it decides to make to itself can be a very intensive process but will an AI see copies and upgrades of itself as itself or as rivals? Without the biological imperatives where does the urge to nurture it's copies come from - or get the positive reinforcement that biological systems provide? I just don't buy the media fictional version of the unstoppable super hacker, where any system can be broken into and taken over; surely if that were so we'd see international banking systems already collapsed from hacker fraud. Protecting data and systems from malicious software and hacker intrusions is not an immature industry and may well be one of the dedicated tasks set for AI's.
  23. How governments respond to the reports and the extent to which they put the wishes of commerce and industry ahead of the science based advice is a big problem. I think the claims that if the style of the reports and advice were different - less alarming, with less emphasis on the likelihood of serious harms - then pro fossil fuels climate science denial wouldn't have traction is pure nonsense. If opponents of strong action are claiming their opposition is due to "alarmist rhetoric" they are probably lying; if the rhetoric was less alarming they would be pleased... and argue the problem isn't so serious after all. I think if pro fossil fuels climate science denial had less high level support and traction then governments would treat the problem more seriously and they would stand up to the opposition from industry. The ongoing power of Doubt, Deny, Delay politics means any actual economic sacrifices in the short term for the sake of the longer term is successfully deemed an unacceptable cost. I think we will continue to make significant progress on low emissions electrification because - unexpectedly - low emissions options have become commercially competitive and can potentially continue to see further cost reductions. But achieving low emissions where it is hard - transport, concrete, steel and other industrial processes - looks more likely to yield cost increases in the shorter term and the power and influence of denial and economic alarmist fear keeps it politically unacceptable.
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