Ken Fabian

The false perception that we are perceiving and thinking and acting in the present when there is actually a significant time lag has intrigued me - a little bit, or maybe a lot of predictive power needs to be involved in doing that.

If we had evidence of an advanced technological society out there messaging them our accumulated knowledge including descriptions and examples of the human genome might make sense, otherwise I think it would be like building pyramids - it will impress humans whilst they are still around but won't actually result in life after extinction. It may have some societal benefits so long as the effort doesn't cost too much.

I don't think I am missing the point. Globally, seagrasses appear to be on par with global rainforests in terms of carbon uptake and, like them, are being lost, not gained. Comparison to Amazon alone rather than global rainforest is misleading. Also Carbon going into ocean sediments is relatively small in the global carbon cycle scheme of things. Carbon going into vegetation, whether on land or marine requires ongoing and enduring gain in biomass; without the assurance it is unduring it remains iffy. I think zero emissions is a prerequisite to the possibility, without assuring it - whilst failure at zero emissions seems likely to assure that it won't stay put. And I don't think it has been shown that enhanced seagrass growth is easier than terrestrial vegetation and soil carbon or that biomass gain wherever it is is a cost effective and scalable way to draw down atmospheric CO2, no matter how tantalising the quoted numbers look. I see preventing their loss, ie stopping them being an emissions source - as both the higher priority and as the prerequisite to achieving a rebound, as are significant emissions reductions. The changes that global warming are causing represent significant threats to that "thousands of years" of sequestration - e.g. marine heatwaves, which shallow waters, ie seagrasses, are at most risk of, have already seen large areas suffer die-backs that saw years of becoming emissions source before recovery. It isn't clear that the recovery brought them back to net CO2 negative or that their survival as sinks can be counted on. No matter that in theory they offer opportunity to draw down CO2 I remain doubtful about achieving recovery equal to past losses without success at achieving zero emissions first. Becoming a significant drawdown of CO2 beyond that - becoming an emissions solution that can lessen the requirements for reducing fossil fuel burning - looks unlikely to me, so I am inclined to object when it is presented as a solution. It isn't any more than Amazon re-forestation is a solution. I see building low/zero emissions energy - emissions reduction - as the most effective action we can take on global warming. It looks necessary to preventing seagrass ecosystem losses as well as enabling potential for any ongoing draw down. How to pay for enhancing seagrass ecosystem carbon draw-down? Mostly emissions offsets are the likely funding source but I am not a fan of carbon offsets; the financing of them, including seagrass management by such means is going to present ongoing challenges starting with preventing abuse of such schemes that includes their role in excusing and justifying ongoing emissions and delay. If we do indeed reach zero emissions other kinds of funding will be needed… well, I don't think we can seriously begin without alternatives to carbon offsets to fund it. It has to be not just subsidised but protected against the variety of human impacts, from inappropriate and excessive fishing to protected against global warming itself that are threatening their viability. I am doubtful of fishing industries being sufficiently supportive of seagrass protection; it may get in principle support but my observation of industry responses to protected no-fishing zones is that they tend to object, often fiercely, rather than support, irrespective of science based evidence of overall benefits to fish stocks. At the individual fishing business level any reduced access - to prevent damage from trawling, anchoring and overfishing, which rate high as threats - will be opposed; having them pay for managing those areas as well seems even more likely to be opposed. This isn't objecting for the sake of argument, it is me attempting to be pragmatic; I am seeing a necessary priority of preventing their degradation and loss and most of all by actual emissions reductions.

The moderating effects on atmospheric CO2 of healthy seagrasses are way short of being a global warming solution. Even if losing more of them will add to the climate problem (the loss of them as sink makes them a CO2 source) I'm not sure how we can greatly enhance their habitats and health, even to the point of retaining as sink what exists before it is lost. Preventing further loss seems the clear priority. Locally as adaptation ( eg to reduce erosion from sea level rise) there may be efforts at enhancing their growth. But climate change itself is probably a negative influence on seagrass health, undermining the likelihood they will "hold carbon for thousands of years". We need more emphasis on emissions reductions through growth of low emissions energy as an element of preserving sea grass health. Not sure ocean floor coverage gives a valid comparison of seagrass effectiveness, although human intervention may be more effective for enhancing seagrasses than for other things that contribute to carbon sedimentation in oceans - being shallow and coastal vs open ocean.

So much depends on what is deemed sin and what isn't, where the rewards and punishments of post life eternity (including the punishment of Hell, according to some but not all) have no half measures; it is all bliss or all unendurable suffering, which seems excessive and unjust when no clear direct instructions were supplied to everyone everywhere and just missing out is deemed Hellworthy. There is no repenting if people don't think it is sin - which I'm told means falling short as much as committing crimes (but a Not-Fundamentalist Christian). It isn't even clear which failures are entrance to heaven level sins. Is ignoring global warming as revealed by seeking understanding of the world and of the consequences of our action through science a sin? For Christians to deny it looks like open denial of the reality made by God, something which can be recognised by the use of observation, intelligence, reason used honestly and shared freely - using "God given gifts". Some very important principles that are often highly regarded by religion have to apply for science to work - honest observation, accurate record keeping, seeking true understanding, sharing knowledge freely with no bearing false witness or making false accusations. Global warming surely is a case where there are consequences for actions in the real world that are not lifted from humanity by repentance, but only by actions in the real world; more like sins of the fathers being heaped upon their children unto eternity - or at least far enough beyond the lifetimes of people now living that it may as well be eternity. Religious people really need to lift their game and apply better standards to what they choose to believe. I've heard the good of religion - that doesn't require religion btw - described as Loving Kindness. Generosity of spirit and so on. From Without it looks like lots of them are falling way short.

I was thinking it is light source that passes through an exoplanet atmosphere too - ones that from our angle don't transit their parent star. It was a thought, but I hadn't thought it through - telescopes less good that that will probably be able to detect them and directly observe atmosphere lit by the parent star's light and get relevant chemical information from it.

I expect this type of observation and analysis of exoplanet atmosphere is the most likely way we will detect signs of life outside our solar system. Impressive to do so with a planet and star so far away. Not going to find life on this specific planet though, unless it is very different to life as we know it. And the method will be limited to planets that transit between the parent star and our solar system. I don't know if it could become possible to use more distant starlight that way, ie not confined to light from the parent star - seems unlikely, but not so long ago detecting any exoplanets seemed unlikely.

I did a quick look to affirm my recollection that it mostly a problem of human senses and the nausea and discomfit from the mismatch between what our sense of balance is saying and what our other senses say. Sounds a lot like the spinning sensation from lying down drunk on alcohol. I expect actually moving around and adapting our motions to such an environment isn't the problem, the problem is people feel ill. Whilst actual conditions can't be tested there have been attempts to mimic some of the effects using centrifuges and rotating spaces on Earth. A few different conclusions cited at http://www.artificial-gravity.com/Dissertation/2_2.htm - eg - @Gian - I did watch some of the vid starting from the point you picked out. Sorry, not going to watch the whole 30+ minute video (a synopsis would be good) but what I did watch made no mention of the role of the sense of balance (vestibular/inner ear), only more direct sensations of changing directions and strengths of pseudo gravity. Did I miss it or is it absent? It would be a serious omission - it wasn't hard to find references to the disorientation and nausea as one of, if not the most significant problem for human occupants.

My understanding is this an issue with the human inner ear, the motion/balance detection part. There is a difference and mismatch between the perceptions of motion, where eyes and other senses say one thing - that you are within a motionless space - but the inner ears are detecting rotation and that becomes disorienting and nauseating. Those little stones in those ear canals - the semi-circular canals - will keep giving the sensation of rotation and being unbalanced unless the rotation is slow enough.

Ending corruption would be up near the top of my list, both the illegal "hard" corruption where appropriate laws exist but bribery, threats and inducements assures no prosecutions and the legal "soft" corruption where undue influence assures appropriate laws are weak or don't exist at all. I suspect that without corruption a lot of problems would be easier, with more resources (money) to use for them. I think we would see more actions taken around issues where vested interests have successfully evaded responsibility and accountability eg global warming would be dealt with more effectively.

Which makes me wonder what we are arguing about - since that is what I have repeatedly been saying. I think this is incorrect - convection requires a difference in density (and gravity... or an acceleration like a centrifuge provides); different density due to temperature difference is just the most common, but having a different mix of gases with a different density will do it. Hydrogen, being lower density, will make convection. My citing the velocity of hydrogen molecules at 0 C was what I found and was intended as illustrative of the high velocity of gas molecules, far exceeding what gravity will do. I should add that doesn't mean I think hydrogen molecules will be bouncing off the walls and floor in a fraction of a second - they will run into other molecules along the way and how fast it disperses depends on (iirc) mean free path. Read my posts and you will find I spoke of other mechanisms all along. It looks more like you being hung up on diffusion, as if it were inconsequential. It isn't. I don't see how that reveals anything different than what I have been saying. Sure, the hydrogen in the bucket will be displaced faster by bulk gas movement (convection) than it could by diffusion. Not sure I am reading it correctly but a table of properties of Hydrogen (here) has convection (bouyant velocity) at 1.2 - 9 m/s - a lot faster than diffusion velocity of under 2 cm/s, but 2 cm/s is still significant in this hypothetical - the convection won't persist for long but diffusion will - from ceiling to floor of a 3m high space in a few minutes. Which won't be to homogeneity - I am assuming for the first molecules arriving? Sethoflagos or someone else likely knows better than me. Most of it will settle temporarily at the top but diffusion will happen from the moment the lid is removed. Do it in zero gravity without convection and the hydrogen will disperse faster than plain air - because hydrogen molecules move faster and that makes them disperse faster. The specific air molecules of plain air will disperse (and be exchanged by Brownian Motion), without changing concentrations.

Hypothetically, yes; the coolant temperature is often higher than boiling point of water - from added glycol - but without running the engine at lower than ideal temperatures (with reduced efficiency) it won't produce a lot of steam. The waste heat from the vehicle's cooling system could also power a Stirling or an Organic Rankin Cycle engine. In practice these options would be a bulky and heavy additional load for a vehicle to carry and are not practical. Likewise storing the heat as hot water in dedicated tanks and offloading it for use - say home heating - would be impractical. I have some small hope that we will see significant improvements in thermo-electric technologies, including potentially optical rectennas aka nantennas that can turn heat directly into electricity, with some quite profound implications, including the ability to harvest energy from the night sky or sun warmed ground as well as direct solar or utilise waste heat or enable large scale thermal storage. Maybe not ever going to be practical but given the potential it looks as worthwhile as spending big on fusion energy - but I would be surprised if they get as much as 1% of the funding that fusion gets.

Constancy of supply would be the main reason why, including beaming from power satellites in sunlight down to places where it is dark. I suppose they'll have short periods of being in Earth's shadow so no single space solar farm will be enough.

It has been looked at before but technology does advance so another like would be good. I'll be very surprised if this can be a cost effective energy option, let alone something that can help us decarbonise energy production but investigating the possibility seems appropriate for a space agency. However I wouldn't want to see our legitimate goal of clean energy hijacked to advance entirely different goals; the confidence in the clean energy outcomes need to be there, before the massive investments and not buy into the "bootstrap" hype - going there first and then figuring it out just isn't good enough. As I usually do when space based solar gets attention, I wonder whether the energy transmission elements could be used without the solar collectors, to beam power up from one place on Earth and down at another, possibly with an intermediate transceiver to take it to the other side of the world. My understanding is that beaming power loses a lot of power, so maybe not but the less stuff we have to put into space the less it will cost; costs of launching payloads have come down a lot but it is still extremely expensive. Did I read somewhere else that they were considering directly powering things like aircraft with power beamed from space? If so that seems even more unlikely to be feasible - no diffuse beam could do that.

Initially most of the hydrogen would rise due to convection and accumulate in a partially mixed state at the top of an enclosed space - partially mixed because of turbulent mixing as it rises and to a lesser extent from diffusion as it goes. The diffusion would be happening from the moment you lift the lid and it will be in all directions, including sideways and down and around. I would expect the convection to effectively stop when it settles in the top of the closed space and so long at there are no temperature differences, will subsequently be dispersing primarily due to diffusion downwards - because diffusion in other directions will be blocked by ceiling and walls. Give it time and it will mix all the way through by diffusion - with the caveat that there is a very small difference due to gravity, just not enough to be significant, just as dispersal is time dependent and arguably approaches but doesn't ever quite reach absolute homogeneity. Also there are going to be differences in dispersal rate due to the bucket making less room going down from above - effusion? Note that I'm basing this on my admittedly quite basic understandings. I can quote a diffusion coefficient of 0.61×10-4 m2 .s -1 for hydrogen gas (it has no term in it for gravity or direction) but struggle to do the calculations for how fast the accumulation at the top would take to diffuse through the whole volume. The reason I see for gravity to be effectively insignificant is that Hydrogen molecules move at around 2,000m/s at zero C and what gravity adds or subtracts is going to be relatively small. CO2 will diffuse lot slower because it is a heavier molecule - I haven't looked in the right places to a number to it - but it will still diffuse. That heat flows to where it is colder and does not flow to hotter is very like the way concentrations of one gas in a mixture will disperse to lower concentrations but not to higher. Without a source or extreme conditions it all goes one way, towards homogeneity.

It does diffuse downwards. Diffusion works in every direction. It is a case of lag time in mixing, with sources adding it faster than it mixes, not stratification. Any lighter gases accumulating in a roof space, (like CO2 does in low places), are not yet well mixed when they rise (or sink). They may not appear to be concentrated "streams" but there will be enough gas seepage - faster than diffusion can disperse it - to make volumes of lower density air, that flow and rise. Enough in otherwise still air for convection to carry it.

I think this is wrong - or rather, there is no perfectly still air (at greater than absolute zero temperature) because of Brownian Motion at the molecule level. Which is what drives Diffusion. Without a barrier the total volume will end up homogenous -

@studiot my point was to clarify for readers that CO2 in mixed air doesn't separate and sink, even under those circumstances. We don't get stratification of the mixed air, we see stratification of pockets/volumes with different CO2 concentrations that have not mixed - yet. Sources will keep it that way but without them the enclosed air will - eventually - homogenize. Or I should say no significant stratification under ordinary Earth gravity; run it through powerful centrifuges and it can become significant. It is a common misunderstanding (whilst not claiming it of you) that CO2, being more dense, will sink to the bottom - and that the higher atmospheric CO2 concentrations nearer ground level are a result of the CO2 separating rather than the sources of CO2 being at ground level and there being a lag time in mixing. At small scale it mixes by diffusion. At larger scales by bulk air movements, ie wind and turbulence. For example thunderstorms will carry air from ground level to the stratosphere in one go, mixing vigorously as it goes.

2) - I think CO2 concentrations in confined spaces only stay high if there is a source, ie it starts with high concentrations and air mixing is impeded, by lack of air movement. A A fully enclosed space filled with air will still end up well mixed due to diffusion, not separated. A deep shaft with high CO2 that is open at the top will gradually lose CO2 until it has similar concentrations to the open air. No, not lying. Stop trying to sell the notion that climate scientists must be incompetent or biased, ie wrong; climate science is not about "selling" anything other than the best possible understanding of how our climate system works and responds to change, both natural and human caused. That isn't complete understanding but more than enough to know that the global warming problem is real, very serious and won't be self limiting over the timescales that matter to human civilisation and to remnant natural ecosystems.

Thanks iNow - that answer does address the question. I do admit to some lingering doubts about how these economic benefits are calculated - I suspect a rosy glasses/PR team point of view - but accept that it is delivering them. Comparisons to the economic value of funding other things instead will always be difficult and speculative but still is valid to ask.

To be honest I'm a bit disappointed with most of the comments. A bit too much falling back on the old truisms about serendipitous spin offs IMO rather than providing examples of how LHC has been delivering them - because not all research projects do deliver them. thewowsignal might not be contributing much to the discussion but it is a good question. Sure, the LHC's budget is small by the standards of the global economy but that is a disingenuous argument; it isn't a pot of money just waiting for uses to be put to, most of it - more than exists it seems, via borrowing and money creation - is spoken for and still leaves them short. There is no shortage of alternative uses where tangible benefits would ensue, that aren't getting enough. There are tradeoffs. Even the old "space programs delivered so much" thing - where truly massive amounts of government funding delivered some tangible technological advances with economic benefits - dodges the question of whether equivalent funding of other kinds of R&D would have done as much or more. These aren't arguments that much impress me. As science research project budgets go "high end" things like the LHC are very high cost and it is a legitimate question whether they are good value - because there are no shortages of underfunded research projects, with that same innate potential for serendipitous spin offs. Yes, pure research has delivered spin offs with useful applications and I am generally supportive of most kinds of R&D - and I'm pleased that some nations that can afford it do so. I think a complete understanding of the building blocks of matter, even without spin-offs does represent something intrinsically valuable - but not unquestioning support when it comes to how to get there. It isn't entirely clear to me that it is best achieved by this research project rather than a different one.

Sounds like reasonable questions even if a regular internet search should provide an answer to how much it costs. But it is clear - even without knowing the specific numbers - that by most science lab standards it costs a LOT of money. I'm in favour of supporting research for the sake of understanding the building blocks of matter but it isn't clear how it has practical implications and of course there are trade offs; funding isn't infinite and bigger budgets for the LHC can mean reduced budgets for other things. Is it good value for money? I have no idea and with pure research we aren't necessary chasing specific applications, rather we aim for a better understanding of how things really work and hope for applications to emerge. Better understanding of what goes on with fusion and of what is required for fusion energy applications? Better medical or other diagnostic imaging? "Better" thermonuclear weapons? It would be interesting to hear what real world impacts people here think it might have.

So much being said about Elon Musk right now but surely it is as simple as him being a bog standard anti-tax, anti-regulation, anti-union free market Libertarian who's commercial successes give him an inflated idea of his own insights in other areas. His Longtermist human destiny to leave Earth behind thing is a bit idiosyncratic but the temptation to try and remake the greater nation, economy, society more to his liking is not so unusual - just most people don't have the money or influence for it. More to his liking will almost certainly pare down to the same old unexceptional "what is good for my business is good for the nation" that other wealthy industrialists espouse. Which puts him firmly in the US Republican camp irrespective of how welcome the successes of EV's and batteries are to those concerned with the climate problem - who, by the failure of those on the Right to treat it seriously, are more likely to lean Left. The significance of social democratic policies (even the US has them, even if explicitly not referred to as such) to the opportunities for long term capitalist wealth creation won't get any credit. Like other rich and successful entrepreneurs his dealing with politicians and political parties will, unlike ordinary citizens, come with high levels of personal access and is likely to be a lot less ideological than it is transactional, especially given one of his major businesses depends on bidding for taxpayer funded contracts... but not his taxes.

The value to fisheries may be there but there is no existing arrangement (as far as I know) for financing of seagrass habitat maintenance by the fishing industry - and I expect attempts to do so would be opposed. Like a lot of the value derived from environmental "services", they have been treated as free. Taxpayers will foot the bill and the fishing industry will - like most businesses - fiercely resist paying more taxes.

It won't be a major climate solution and can only be an adjunct to building an abundance of clean energy to displace fossil fuel burning - which remains our single most effective action, the one that is not optional. Saving the seagrass that exists - preventing it's loss, which would add to atmospheric CO2 - looks like the more significant thing and that appears to require that shift to zero emissions to prevent the ocean heating that could damage existing area and slow the sea level rise that could kill them. Farming seagasses might help but unless it has some other commercial value to sustain it the funding will be hard to come by and is likely to get better results elsewhere, such as supporting that essential growth of clean energy.