an autodidact meets a dilettante…

‘Rise above yourself and grasp the world’ Archimedes – attribution

Posts Tagged ‘science

Useful stuff on extremophiles and their tricks

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A tardigrade or water bear, emblematic creature for extremophile-philes everywhere. Look em up, cause they’re not mentioned in this article

I’ll try to wean myself from the largely thankless task of writing about politics by picking a topic, almost at random, though one that I know will keep me engaged once I get started.

I was reading an article on the geology of the Earth’s crust and upper mantle (aka lithosphere) the other day, which mentioned the possibility of life in the mantle. Little is known for sure about the mantle’s composition and activity, because until recently drilling down to that level has been just a pipe dream, so to speak. The mantle’s distance from the earth’s surface varies considerably from region to region, but the average depth of the crust at its thinnest, ie under the ocean, is about 6 kilometres. In 2011, microscopic nematodes, or roundworms, were found some 4 kilometres below the surface in a gold mine in South Africa. Other single-celled micro-organisms were found in the region, at depths of 5 kms. Since we’ve rarely plumbed such depths, it’s not unreasonable to suppose that life down that far may be commonplace. We already know that life exists under the sea floor, at immense pressures. At the bottom of the Mariana Trench in the western Pacific, bacteria thrive 11 kilometres below sea level, and some bacteria have been tested in the lab as tolerating 1000 atmospheres of pressure.

Of course, the term extremophile, applied to such life forms, is typically anthropocentric, as they would presumably shuffle off their mortal coils tout de suite when subjected to our torturous environment. Then again…

Extremophiles are of course termed as such when found in conditions that are far from what we would term normal. Such conditions include extremely hot or cold environments, highly acidic or alkaline environments, anaerobic environments, and extreme pressure. They include archaea, the earliest living organisms we know of, some of which have been found to be halophilic (thriving in high salt conditions) or hyperthermophilic (lovers of temps around 80°C).

So how far down can these organisms go? What do they live on? What do they look like and how do they relate to other organisms on the bush of life?

This article from National Geographic online suggests the possibility of an ecosystem existing some eight or nine kilometres below the Mariana Trench. The trench is a subduction zone, a region known to provide pro-life environments of sorts. Analysing such regions requires geological as well as microbiological expertise. A geological process known as serpentinisation provides an ecosystem for methane-consuming microbes. Serpentine is a mineral formed deep in the lithosphere ‘when olivine in the upper mantle reacts with water pushed up from within the subduction zone’, according to the article. Hydrogen and methane are by-products of this reaction, and this serpentinisation process is already known to create microbial habitats at oceanic hydrothermal vents. Furthermore, in recent years, serpentinisation has been found ‘everywhere’, at subduction zones and within mountain ranges, suggesting that methane-supported life may be commonplace, and may even exist elsewhere in the solar system where there is tectonic activity, and an abundance of olivine.

Organisms living at great depths, under great pressure, are called piezophiles. So what is it that permits these bacteria, archaea and other unicellular organisms to thrive – or perhaps only just survive – in such conditions? There’s no one-size-fits-all answer, as some, such as xenophyophores, which are found at depth throughout the world’s oceans, are relatively complex creatures that appear to have adapted over time to increased pressure in order to benefit from benthic provender, while others like Halomonas salaria, a proteobacterium, are obligate piezophiles, unable to survive in under 1000 atmospheres. Unsurprisingly the outer membranes of these organisms are necessarily different in structure and composition from your common or garden microbes, but also unsurprisingly, it has proved difficult to analyse the structural features of piezophiles under lab conditions, though it’s clear that regulation of membrane phospholipids is key to maintaining a stable internal environment, which can not only withstand pressure, but also extremes of heat or cold or acidity. Proteins are also modified to maintain function. Although little is yet known about these organisms, the variety of their environments suggest a variety of adaptations independently arrived at. Most are autotrophs, or self-feeders, able to build organic compounds such as proteins through chemosynthesis in the absence of light. Many of them appear able to slow their metabolism and their reproduction rate by many factors.

Researchers are becoming increasingly interested in extremophiles in general, as they’ve widened the possibilities of life in environments hitherto dismissed as unviable – in boiling water or under mountains of ice for example – just as we’ve begun to discover or further explore other planets (and moons) within and beyond our solar system. The field of microbiology has also made great strides in recent decades. Don Cowan, a senior researcher at the University of Pretoria, describes the microbiological ‘revolution’ of the eighties:

In less than a decade, a combination of conceptual, scientific and technical developments all came together. These included the ability to purify total environmental DNA, the development of special marker sequences that can identify different microbial species, and the advent of very fast, very cheap DNA sequencing techniques.

Collectively known as metagenomics, these developments hugely stimulated the field of microbiology. They have done so across diverse areas of science, from biological methods for cleaning up environmental pollution and contamination, to human disease.

Researchers are applying these techniques to the examination and possible exploitation of extremophiles, for example to improve drought or temperature tolerance in plant species, for various pharmaceutical applications and possibly for the development of biofuels, as heat-tolerant enzymes enable plant tissues to be broken down more readily. The range of products and processes that can be improved by tapping into the enzyme production of various types of extremophiles is potentially vast, according to James Coker, a researcher at the University of Maryland’s Department of Biotechnology. In a 2016 paper, Coker admits that research in this field is new, but real progress has already been made:

Four success stories are the thermostable DNA polymerases used in the polymerase chain reaction (PCR) 17, various enzymes used in the process of making biofuels 18, organisms used in the mining process 19, and carotenoids used in the food and cosmetic industries 20. Other potential applications include making lactose-free milk 1; the production of antibiotics, anticancer, and antifungal drugs 6; and the production of electricity or, more accurately, the leaching of electrons to generate current that can be used or stored 21

That last-mentioned application is of particular interest (as are all the others), as clean electricity production and storage is a high priority issue for some. Extremophile microbial catalysts can be used to drive microbial electrochemical systems (MES), a new TLA which may or may not catch on. Related TLAs include the MFC (microbial fuel cell) and the MEC (microbial electrolysis cell). Without losing myself in too much detail here, the exploitation of these microbes to help drive reactions at the electrodes has a number of useful applications, such as the remediation of waste-water, desalination, biosensing and ‘generating electrical energy from marine sediment microbial fuel cells at low temperatures’ (Dopson et al, 2016). None of this is, as yet, set to revolutionise the clean energy industry, but these are just some of the largely unsung incremental developments that are, in fact, moving us towards more clever and efficient use of previously untapped renewable resources. I was about to use the metaphor ‘at the coalface’ – which would’ve been appropriately inappropriate.

It’s impossible for we dilettantes to keep up with all these discoveries and developments in a detailed way, but we can at least feel the excitement of work being done and advances being collaboratively made, as well as sensing the many obstacles and unforeseen complexities involved in transforming the viability of these amazing life-forms and their products into something viable and possibly life-transforming for the humans who have discovered them and unlocked their secrets. When politics and our inhumanity to others (human and non-human) lets us down, we can still marvel at our relentless drive and ingenuity.

 

Written by stewart henderson

July 14, 2018 at 8:50 am

Is free will a thing? Apparently not.

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Science appears to be cutting the gordian knot of philosophical isms

Canto: The subject of free will often comes up, and I’ve recently read Sam Harris’ booklet on it, so I want to state right now my view that if we do have free will, it’s a far more circumscribed thing than many prefer to believe, and I’m open to the view that it doesn’t exist at all.

Jacinta: Yes I’ve read a fair bit on the subject over the years, including Dennett’s Elbow Room in the eighties, and a collection of essays edited by Bernard Berofsky, dating back to the sixties, but like everyone I’ve forgotten almost all of any book I’ve read within weeks of having read it, so it’ll be good to get back to the subject enfin. 

Canto: But have you been exercised by the actual subject, intellectually speaking?

Jacinta: Very much so. Let’s return to our old friend the Dunedin longitudinal study, which indicates that the various personality types – roughly characterised as well-adjusted, confident, reserved, under-controlled and inhibited – are established very early on and rarely change outside of neurological damage. These constrain free will, as does your broad environment, for example whether you’re a scion of the British aristocracy or the offspring of Mongolian goat-herders. You’re not free to choose these things or your genetic inheritance or, presumably, your neuronal wiring, at least not as a youngster.

Canto: I think the free will people would concede all that, but their best argument would be that in spite of all the determining factors that make you who you are, your moment-to-moment decisions – whether to get out of bed or sleep in for a while, whether to break your diet or stick to it, whether to watch a TV program or go to the pub, whether to study physics or psychology at uni (assuming you’re qualified to do either), and so on – these decisions are made of your own volition, so you are responsible for them and nobody else. If there’s no free will, there’s no responsibility, therefore nothing or nobody to praise or blame. And then where would we be with our ethics?

Jacinta: That’s interesting because we often get confused about that, or some people do. I would say most people believe we have free will, so we’re happy to punish people for criminal acts. They chose to commit them after all. But take those serial paedophiles that the tabloid press like to call ‘monsters’. They describe them as incorrigible – that’s to say, uncorrectable. So they should never be released again into the public, once they’ve been proven to commit some heinous paedophile act. What’s being claimed here is that the paedophile can’t help but commit these acts again and again – he has no choice, and presumably had no choice to begin with. But prison is a terrible punishment for someone who has no choice but to be what he is. They’re denying that he has free will, but punishing him for acts that should only be punished if they’re undertaken freely. You can’t have it both ways.

Canto: Well put, and my own tendency towards what used to be called hard determinism comes from reading the writings of ‘compatibilists’ or ‘reconciliationists’ who wanted, I thought, to give themselves as much credit for their success as they possibly could, seeing that they were successful academic philosophers earning, I assumed, the kind of salaries I could only dream of. On the other hand, as a hard determinist, I naturally wanted to blame everyone else, my parents, my working class environment, my lack of wealthy and educated connections, for my abject failures in life.

Jacinta: You jest a little, but I know you’re being essentially serious, in that the Gina Rineharts of the world, inheritors of millions, are the biggest spruikers of the notion that everyone is free to be as rich as everyone else but most people are just too slack, or, for reasons unfathomable to her, aren’t sufficiently interested in material self-enrichment, so they get precisely what they deserve.

Canto: Or what they’re destined to get. Just reading through some of that old philosophical material though, I find myself reliving my impatience with the academicism of philosophy. For example, the endless analysis of ‘able to’, as in ‘she’s able to play the piano’ but she can’t because she hasn’t got one right now. So she has the skill but not, right now, the equipment. Perhaps because she’s fallen on hard times and has had to sell it. Which leads to having ‘potential ability’. She might have been one of the world’s greatest soccer players, having the requisite skill, speed, drive, etc, but she was never introduced to the game or was discouraged from playing it.

Jacinta: She was told to study piano instead. Or more importantly, potential scientific geniuses who just didn’t get the opportunity due to a host of external circumstances, to attain that potential. They say geniuses are made not born, but they require external material to make themselves into geniuses, if that’s what they do. The point is that you can get caught up with words like ‘able to’ or ‘could have done otherwise’, which you can then interpret in varieties of ways, and it becomes almost a philosophy of language thing. But the main point is that although it seems obvious that you can choose between having a piece of cake before bedtime or not, these aren’t the most important choices..

Canto: And maybe even these choices aren’t as freely made as we might think, according to research Sam Harris cites in his essay. It seems science is catching up with what I knew all along. Not only do we have no control whatever over our genetic inheritance, but the way those genes are expressed, based largely on environmental factors, which lead to our brains being wired up in particular ways to release particular levels of hormones and neurotransmitters in patterned ways, leading to those character types identified in the Dunedin study, all of this is way beyond our conscious control. In fact it’s fair to say that the gradual retreat of the notion of free will is largely the result of the assault on the primacy of consciousness. Far more of what we do is less conscious than we think.

Jacinta: Yes the neurophysiological research around everyday ‘decisions’ is compelling, and disturbing to many. It suggests that our feeling of having freely decided on something is a delusion, though perhaps an evolutionarily useful one. Believing in free will usually entails belief in personal moral responsibility, and thus supports punishment for damaging acts and reward for heroic or beneficial ones. And  some research has actually shown that people primed to disbelieve in free will are more prepared to cheat and pilfer than those who aren’t.

Canto: So if this continues, this spread of disbelief or skepticism about free will, it may lead to a spike in criminal activity, large and small?

Jacinta: Well I don’t know if there’s been a rise in crime, but there has certainly been a rise in ‘my brain made me do it’ defenses. The effect of all this might be a ‘go with the flow’ attitude to pursue self-interest because your brain’s wiring supposedly impels you to.

Canto: So, that’s interesting, maybe a solution to this is more knowledge. The understanding that we’re the most social mammals on the planet, and that what we do, such as cheating and pilfering, adversely affects others, which will ultimately rebound on us. Even our brain’s own wiring has been caused by environmental factors, primary among those being human factors. So emphasising that our ‘self’ is more of a social self than our privileged access might lead us to believe will encourage us to consider what we owe to the wider society that helped shape us.

Jacinta: Yes, that’s a good point. And I think, as Harris and others point out, jettisoning the free will notion should help us reduce our tendency to blame and hate. I struggle myself with this – I ‘hate’ Trump, but I quickly realise he’s always been like this, and I can’t even blame his parents, who are what they are, etc. So I turn, as I think I should, to a US political system that enables such a person to reach the position he’s reached. In focusing on this system I can heap blame upon blame to my heart’s content, which I always love to do, without getting personal, which may have rebounding consequences for me. It’s a great solution.

Canto: Anyway, I think we’ve just scratched the surface with this one. Don’t we sometimes appear to agonise over decisions? People make lists of pros and cons about whether to spend x money or whether to travel to y, or whether or not to break up with z. How does this sort with a lack of free will? There must be a lot more to say.

Jacinta: It’s determined by our brain’s wiring that we agonise over some of our decisions and not over others. And how often do we make those lists you speak of, often prompted by others, and then just go with our original intuition?

Canto: Hmmm, I still think this is all worth further consideration…

Jacinta: I don’t think there’s any way you can seriously argue for free will. The argument is essentially about the consequences.

References

https://www.theatlantic.com/magazine/archive/2016/06/theres-no-such-thing-as-free-will/480750/

Sam Harris, Free will

https://theforeveryears.wordpress.com/2016/06/30/dunedin-study-findings-the-importance-of-identifying-personality-types-at-a-young-age-by-kirsteen-mclay-knopp/

Bernard Berofsky, ed, Free will and determinism

 

Written by stewart henderson

May 15, 2018 at 10:16 am

Archimedes, the Mathematikos and the birth of science

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Rise above yourself and grasp the world.

Archimedes (attributed: inscribed on the Fields Medal)

One of Archimedes’ most spectacular inventions, the gravity-defying spiral-in-a-cylinder, or screw – still effective

Canto: So we spent some time at the Waikato museum in Hamilton, braving the school holiday crowd to view an exhibition celebrating the work of Archimedes (c 287-212 BCE) and his fellow mathematikos, and noting how it inspired the likes of Leonardo some 1800 years later. So let’s talk about their breakthroughs and about why there was such a gap between their clever contrivances and the maths on which they were based, and the scientific revolutionaries of the sixteenth and seventeenth centuries.

Jacinta: These are intriguing and vital questions. Many modern scientists have been dismissive of the science of the ancient Greeks because they think of Aristotle as representative. I think it was Lawrence Krauss I heard complaining of Aristotle’s belief that women had less teeth than men – apparently he never thought to count them! But the fact is that, though Aristotle is sometimes known as the father of empiricism, he probably doesn’t deserve that title except in respect of ethics, and politics, which he based on what actually works for societies and city-states, which is why he collected and analysed their constitutions. The mathematikos, on the other hand, eschewed ethical issues in favour of mathematics – geometry in particular (think Euclid). And, especially in the work of Archimedes, they enjoyed phenomenal success in many practical areas.

Canto: Especially warfare apparently. It seems Archimedes in particular was called on more than once to defend his city, Syracuse, with war machines. In the blurb to the exhibition, they mention ‘torsion ballistae’. Can you please explain?

Jacinta: Well, I’ll tell you about the torsion siege engine. It replaced the earlier tension siege engine, possibly invented in Syracuse in the time of Dionysius the Elder (c 432-367 BCE) – so the engineering of weapons of war was already a big thing at the time. It was basically a massive catapult. The first torsion device of this kind is generally dated to the time of Philip II of Macedon, Alexander’s dad, circa 340 BCE. The first extant evidence of its use comes from a list of items in the arsenal of the Acropolis in Athens dating to 338-326 BCE. So what is torsion? It’s the energy created by winding something up, like a spring. In earlier times, human hair, horsehair and animal sinews were used for this purpose.

Canto: So plats give you energy?

Jacinta: Torsion basically means twisting. The Greeks apparently used specially cured sinew combined with human or animal hair to create a ‘torsion bundle’ – we don’t know what the exact recipe was – which was fixed to a wooden frame and could be twisted and released regularly via levers without breaking. But the key development was the mathematics of these devices. This military website describes:

The critical dimension was the diameter of the sinew “spring” or torsion bundle. For a bolt shooter, the ideal diameter was one-ninth the length of the bolt. For a rock thrower the ratio was more complex; the diameter (d) of the bundle in dactyls (about 3/4 inch) should equal 1.1 times the cube root of 100 times the mass of the ball (m) in minas (about a pound). Saddled with a numerical notation system even more awkward than Roman numerals, the Greeks developed sophisticated geometric methods to compute cube roots.

Canto: So how were these maths – these geometric methods – derived. Euclid was the great geometer of the time, wasn’t he?

Jacinta: Actually, though the exact time-frame of Euclid’s life isn’t known, his Elements came out after this invention, but before the work of Archimedes. Clearly it must’ve been drawn from earlier mathematikos, such as Eudoxus, who worked out, via an early version of integral calculus, that areas of circles relate to squares of their radii, and volumes of spheres relate to the cubes of their radii, and various other relations between volumes and dimensions of pyramids, cylinders, cones etc, which obviously had practical applications as described above.

Canto: Okay, so tell us about Archimedes’ particular contributions, and about why the great work of the mathematikos was apparently discontinued after Archimedes. Considering that the Roman Empire didn’t become christianised until some 500 years after Archimedes’ death, we can’t really blame the Christians – can we?

Jacinta: Well, I mentioned that early version of integral calculus. It was called the method of exhaustion, a kind of geometric calculus which Archimedes took further than anyone before him, both in theoretical terms and via practical applications. Now I’m far from being a mathematician, but I’ve come to appreciate the essentiality of maths in understanding our universe – so much so that I perhaps regret my lack of mathematical expertise more than I regret anything else in my old life. This is by way of saying that I won’t try to explain Archimedes’ maths – but an understanding of maths is essential to understanding the magnitude of his achievement.

Canto: Okay, so what about his inventions?

Jacinta: Well the key is the application of complex and what might have seemed pointlessly abstract maths about the relations of ‘perfect’ shapes such as spheres, cones and cylinders to real world problems and their solutions. The lever is a good example. Archimedes didn’t invent levers but he was clearly fascinated by them. And it shouldn’t take long to realise that they have immense practical applications. Doors are levers, as are nail clippers, nutcrackers and see-saws. Archimedes wrote what we now call a treatise, On the equilibrium of planes, to explain the maths behind them. But the best illustration of Archimedes’ combination of theory and practice is probably what is known as Archimedes’ principle, which essentially launched the field of fluid dynamics, or fluid mechanics:

the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces and acts in the upward direction at the center of mass of the displaced fluid.

It comes from another treatise of his, On floating bodies. Now let me see if I can explain this. Take an object, any object. The downward force exerted on it is its weight. Immerse it in water. It will float or it will sink, and even if it floats it’ll be partially submersed. The principle doesn’t apply to objects that sink, which will have a density of anything over and above a certain level which permits it to float – I think.

Canto: But that principle, though it comes from a treatise about floating bodies, doesn’t distinguish between floating and sinking. It says ‘fully or partially submerged’…

Jacinta: But an object can be fully submerged and still float. To sink means to continue in a downward direction.

Canto: I’ve found that an object that floats – I’m thinking of water as the fluid, and perhaps I shouldn’t – always seems to have a certain proportion above the water level. Think of icebergs, and human bodies. But I think I get it – the force that keeps you up and floating will be equal to the weight of the water your body displaces… So if I was ten kilos heavier, I would still float but the upward force acting on me would be greater, but not by ten kilos, rather by the larger volume of water my larger body displaces measured in kilos, or by some measure of force…

Jacinta: I don’t think that’s wrong, but I’m not sure if it’s right. The problem for me is that the principle as stated doesn’t specify a floating body, only a body immersed – partially or fully in a fluid. Think of a stone dropped in water. It sinks. To the bottom.

Canto: And if the fluid is bottomless will it just keep on sinking? It’s as if there’s no upward force acting on it at all, or very little. I’m imagining a bottomless column of still water here, not an ocean with its currents…

Jacinta: Ha, I was thinking of a bathtub, but with a bottomless well, it will depend on the density of the stone. I think at some point it’ll slow down and be suspended. I’m sure water pressure will play a role, and density – of the water. And density is somehow related to pressure, and I’m getting lost…

Canto: We may need to do a Khan academy course. But getting back to Archimedes and the mathematikos, why was so little of their work built upon, until Galileo and others became inspired so many many centuries later?

Jacinta: That’s possibly too long a story to go into here, not that I’m much equipped to tell it. It no doubt relates to the gradual decline of the increasingly dispersed Greek culture of the Hellenistic and post-Hellenistic era. I wouldn’t want to say Christianity was a major cause but it certainly didn’t help. By the time the Roman Empire became Christianised, the culture that created figures like Archimedes had long passed. Roman culture was a lot more militaristic and less speculative. Blue sky research wasn’t in vogue. Of course, why all this happened I wouldn’t venture to say without many years of research into the cultural changes then occurring. But the slowness of the scientific recovery, that I would attribute to Christianity, and later to the conservative turn in Islam that still prevents original science from being practiced in those countries where it holds sway.

Written by stewart henderson

May 2, 2018 at 9:13 pm

is this the best use of journalism?: attn Katie McBride and Outline magazine

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Rat Park, in colour

Jacinta: Now we’re going to do something slightly unpleasant but wholly necessary: take someone to task, as teachers must occasionally do.

Canto: Yes, it relates to a previous post, a recent one, about Rat Farm and the war on drugs.

Jacinta: In writing that post we happened upon an article entitled  ‘This 38-year-old study is still spreading bad ideas about addiction” – which kind of shocked me with its provocative title. It was written by Katie MacBride and published by Outline, an online magazine. I only skimmed the article at the time, bemused to find the Rat Park experiment still creating such negative vibes after all these years, but some obvious problems in the article stood out, even on the most cursory reading, so I’ve decided to revisit it with a more careful analysis, with Canto’s help.

Canto: Well the first red flag with the article comes with the first words, before even the title. Pop science. In other words, this article, or rather its subject, should be filed in the category of ‘pop science’, as opposed to real science. This is designed to instil prejudice in the reader from the outset, and is clearly a cheap trick.

Jacinta: Yes, and for an immediate antidote to this kind of cheapsterism, I’d advise anyone to read the Wikipedia article on the rat park experiment, which is calmly and reasonably presented, as is usual. And let me here heap praise on Wikipedia for its general reliability, its objectivity and its pro-science approach. It’s one of the greatest gifts the internet has provided to our world, IMHO.

Canto: The next red flag comes with the title – ’38 years old and still spreading bad ideas’…. As if the date of the study is relevant. There are a number of landmark psychology studies even older than Bruce Alexander’s Rat Park, and also ‘flawed’ – of which more later, – which continue to resonate today for obvious reasons…

Jacinta: Yes, for example Stanley Milgram’s electric shock experiments, over fifty years ago now, and the Stanford Prison experiment of 1971. These, and Alexander’s Rat Park experiment, deserve to be regarded as landmark pieces of work because they make you think. And they often overturn previous thinking. They shake our complacency.

Canto: And what about the latter part of the title, that Alexander’s work is still spreading bad ideas?

Jacinta: It’s interesting that she claims this, considering that the main reason Alexander embarked on this study was to combat bad ideas – particularly the war on drugs itself, and the prevailing view, promoted by the likes of Harry Anslinger and his zero tolerance approach to drugs such as cannabis and cocaine, that use of these drugs led inevitably to a kind of madness that was extremely harmful to self and others. Remember the rat adverts of the time, which showed rats dropping dead after regularly imbibing morphene-laced water, with the message ‘this could happen to you’.

Canto: Yes, and the rats may well have been choosing the drug over plain water because, like many lab rats of the time – hopefully things have changed – the conditions they were kept in made their life something of a living hell. What Alexander’s experiment showed was that, given a far more enriched environment, rats made far less simplistic and self-destroying choices. That’s all. So how could this be a ‘bad idea?’

Jacinta: MacBride doesn’t say. But to be fair, Alexander’s thesis may have been that opiates aren’t addictive at all, which is not what his results showed – they showed that environment matters hugely in respect to the willingness to get hooked on drugs. And that’s a really really important finding, not a ‘bad idea’.

Canto: And we’re still on the title of MacBride’s essay, which is followed by a tiny summary remark, ‘The Rat Park study was flawed and its findings have been oversimplified, but it keeps getting cited.’ Any comments?

Jacinta: Yes – as a regular listener to the podcasts of the Skeptic’s Guide to the Universe (SGU) over the years, as well as a reader of Ben Goldacre and other science-based critics of medical/psychological studies and experiments, I can safely say that every piece of research or experimentation, since the dawn of time, is flawed. Or imperfect. Or limited. Some more than others. of course. So to say the study is flawed is to say nothing at all. Every episode of SGU, and I’ve listened to hundreds, features one piece of published research or other, which Steve Novella picks to pieces to determine whether it’s very or mildly interesting, or a piece of rubbish, but even with the best study, the mantra is generally ‘needs more research’. So a critic needs to show how an experiment is flawed, and how those flaws affect the results. And MacBride’s effort to do this is pretty abysmal.

Canto: Okay, before we examine that effort, I’d like to quote something from early on in MacBride’s article:

The Rat Park study undermined one popular misconception about addiction, that chemistry of drugs is the single most important factor in addiction. But instead of pushing the popular understanding forward, it merely replaced that misconception with a new one: that environment is the most important factor.

What do you make of that? Do you think it a fair description of the study?

Jacinta: It’s an odd description, or mis-description, of the study. The first sentence you quoted isn’t problematic. The study did undermine the idea that it was all about chemistry. Or rather it would have, had anyone paid attention to it. It should have, as MacBride implies, but instead of then regretting that the study didn’t have any impact, she presents it as deserving of oblivion. It doesn’t make much sense.

Canto: The quote claims that it’s a misconception that environment is the most important factor in drug addiction. Do you agree?

Jacinta: I don’t know if it’s the most important factor, but it’s obviously an important factor, and the Rat Park experiment provided strong evidence for this. It seems MacBride is confusing Alexander’s possible claims or commentary on the study with the study itself. The study doesn’t prove that environment is the most important factor, but it certainly makes you think about addiction in a very different way from the horrific but dumb rat ads  that prompted it. It makes you think, as all good studies do, and that’s something MacBride seems extremely reluctant to admit. And I wonder why.

Canto: But MacBride does provide cogent criticisms of the study, doesn’t she?

Jacinta: Well, she quotes one particular critique of the study, by a Dr Sam Snodgrass, who found that the Rat Park environment, in which rats were no longer isolated and therefore mated, as rats are wont to do, would have rendered the findings questionable. According to Snodgrass, “You can’t have one group of subjects mating and with pups and compare it to a group that doesn’t engage in these behaviors and say that the difference between the two groups is caused by environmental differences.” But I beg to differ. An environment in which you’re isolated and unable to have sex is obviously very different from an environment in which you breed as normal – especially for rats. As to the rat pups ruining the experiment, I think if you looked closely at any rat study in which rats get to live together and breed, the actual experiment would be more messy than the published results indicate, but I doubt the problems would be so great as to invalidate those results.

Canto: And what about attempts to replicate the experiment?

Jacinta: Well there seem not to have been enough of them, and that’s not Alexander’s fault. Above all, similar experiments should have been conducted with different drugs and different concentrations etc. And of course rats aren’t humans, and it’s hard to bridge that gap, especially these days, as lab testing of other non-human animals (and rats too) is increasingly frowned upon, for good reason. I note that MacBride briefly mentions that others did replicate Alexander’s results, but she chooses to focus almost wholly on those who found differences. She’s also quite brief in describing the obvious parallel, presented in much greater detail in Johann Hari’s Chasing the scream, of American soldiers taking heavily to heroin in the alienating environment of Vietnam and giving them up on their return to what was for them an obviously more enriched environment. The facts were startling – 20 time the heroin addiction in Vietnam, as MacBride admits – but not much is made of them, as she is more concerned to pour cold water on Rat Park, so to speak.

Canto: Yes it’s strange – MacBride admits that the war on drugs has been an abject failure, but her obsession with criticising Rat Park prevents her from carrying through on that with, for example, the alternatives to this American approach in Europe. She mentions the again startling fact, reported by the Brookings Institute, that the combined hardcore user rate for hard drugs was approximately 4 times higher in the US than in Europe, after decades of the US war on drugs, but fails to note that the Rat Park experiment was one of the main inspirations in implementing more humane and vastly more successful policies, not only in Europe but, more recently, in some US states.

Jacinta: Yes MacBride is clearly concerned to get everyone’s facts straight on the opioid epidemic that’s currently gripping the US, and about which I honestly know little, but I think she has gone overboard in seeking to vilify the Rat Park study, which surely has little to do with that epidemic. The Rat Park experiment hardly promotes drug-taking; what it does strongly suggest, as does Johann Hari’s book, is that environment is one of the most important factors in determining a person’s willingness to escape into drugs. My own personal experience tallies with that, having been brought up in a depressed and disadvantaged region, hard-hit in the seventies by economic recession, and watching the illicit drug trade take off around me, as houses and gardens became more and more derelict.

Canto: Yes, it’s hard to understand why she’s focusing so negatively on Rat Park, when the problem is really one of interpretation, insofar as there is a problem. And I don’t know how it relates negatively to the opioid crisis. Maybe we should find out more about this crisis, and do a follow-up?

Jacinta: Maybe, but it’s so hard trying to fix the world’s problems… but of course that’s what we’re here for…

 

Written by stewart henderson

April 13, 2018 at 11:53 am

transporting water in trees – the finale, perhaps

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‘If I do not succeed today, I will attack [the problem] again on the morrow’

Mary Fairfax Somerville (1780-1872), mathematician, physicist, autodidact, genius

 

trees are so interesting… some more than others

So far my journey into this subject has proved fascinating but inconclusive, but a Veritasium video has helped me with the final solution, though it’ll still take a while to get my head around it.

There’s more than one problem involved here, as I’ve mentioned. There’s the transport problem and the ‘knowledge’ problem; how does the tree ‘know’ when it needs to bring up water, and how much to bring up?

Let’s look at transpiration again. Think of it like our perspiration. When we exercise, or even just when we’re in the sun, we sweat. The sweat then evaporates, cooling our bodies, and if we need to, we produce more sweat. It’s not conscious, we don’t have to know how much more sweat, or water, to produce, it’s just a ‘process’, no doubt a very complex one, like the process in trees and plants. However, I’ll come back to transpiration later.

Water can move up the xylem tube to the leaves of a tall tree at a maximum rate of a third of an inch per second, according to Peter Wohlleben (obviously translated into American). That’s around 2.5cms every 3 seconds, or 50cms per minute. Or 30 metres per hour. That’s rather impressive. When I told a friend about this, she said you can hear the water gushing up the trunk if you put your ear to it. Maybe that’s true.

The Veritasium video starts with another fascinating question – how can trees get so tall? And of course it’s worth noting that different species of trees have their own ‘natural’ height limits, levels of ‘bushiness’ and so forth, which is obviously affected by their particular environments as well as their genes. The tallest are around 100 metres. And one major limiting factor is that they need to transport water from roots to topmost leaves. You can’t suck water up a straw for more than ten metres, because you’ll have sucked all the air out, creating a vacuum, a pressure difference of one atmosphere. To suck the water ten times that high would create a difference of 10 atmospheres or more. So even if trees could suck somehow, the task seems impossible…

Back to transpiration – when water evaporates from the leaves, this ‘pulls up the water molecules behind it’, according to the video, though it doesn’t give an account of this ‘pulling’ mechanism, which in any case couldn’t account for the 100-metre movement, again because of the pressure limitations. Interestingly, many websites, including Wikipedia, describe transpiration as the whole process of water transportation in plants, rather than the process of evaporation and replacement in the region of the leaves, so it can be confusing. In any case the ‘pulling’ up of water to replace molecules lost in evaporation is explained by the cohesion-tension theory, as referred to in a previous post. It’s about hydrogen bonding and the adhesive and cohesive properties of water. Yet it seems miraculous that this process can explain such a vast movement against gravity. The xylem inside trees – those dead, hardened, hollowed-out cells – provide an uninterrupted column for water to pass through (the apoplastic pathway), but the distance would seem to cause pressure problems. The video discounts osmotic action, and here I have to take a quick primer on osmosis, because I don’t get it:

If there is more solute in the roots than in the surrounding soil, water would be pushed up the tree. But some trees live in mangroves where the water is so salty that osmotic pressure actually acts in the other direction, so the tree needs additional pressure to suck water in.

I don’t know why that seems counter-intuitive to me. Is it because I don’t think (sufficiently) scientifically?

Right, after a glance at a couple of videos, I think I get it. I remember the mantra that osmosis is the passage through a semi-permeable membrane (and when does a fully permeable membrane stop being a membrane?) from high to low concentration. But of course it’s the concentration of water molecules that passes from higher to lower, not the concentration of the solute. Duh. And its continued movement up the tree would have something to do with the polarity of water, its bonding properties. But anyway, osmosis isn’t the answer, as mentioned. And neither is capillary action, as explained before.

So now, to the actual explanation, which, at this moment, I certainly don’t get, but I’m going to try. It has to do with gases, liquids, vacuums, pressure and the properties of water. The video provides its final solution, so to speak, in less than two minutes of air-time, but for unscientific me, after a few viewings, it raises more questions than answers. So I’m going to analyse it bit by bit, and this may turn out to be the longest single post I’ve ever written.

So first it’s pointed out, by Hank in the video, that the lowest you can go, pressure-wise, is a vacuum. But that’s only for gases. So a perfect vacuum equals zero pressure. You need something to exert pressure – if there’s nothing there, no pressure:

But in a liquid you can go lower than zero pressure and actually get negative pressures. In a solid, we would think of this as tension. this means that the molecules are pulling on each other and their surroundings. As the water evaporates from the pores of the cell wall, they create immense negative pressures of -15 atmospheres in an average tree.

This negative pressure or tension idea doesn’t come easily to me, and it’s the key to the explanation. It’s certainly accepted science, though there are questions about how much negative pressure water can withstand, as this scientific paper explores, before cavitation. The negative pressure of -15 atmospheres is approximately -1.5 Mpa (megapascals). Experiments described in the scientific paper show that, depending on circumstances, liquid water can sustain far greater negative pressures than -1.5 MPa.

I might be wrong, but it seems to me that negative pressure is like pressure from within (hence tension) rather than from without. I’m going to have to accept this as true, and try and make sense of the rest of the explanation:

Think about the air-water interface at the pore [of the cell wall – is he talking about the whole xylem tube as a cell?]. There’s one atmosphere of pressure pushing in and -15 atmospheres of suction on the other side. So why doesn’t  the meniscus break? Because the pores are tiny – only 2.5 nanometers in diameter. At this scale, water’s high surface tension ensures the air-water boundary can withstand huge pressures without caving [cavitation].

So there’s an air-water boundary (the meniscus) at the pore, which presumably means the top of the column of water. But why does he call it a pore, which we usually think of as a hole, e.g. in the skin. This term isn’t explained at all, it’s just suddenly introduced. Does he mean the xylem column is 2.5 nm wide? No, the average xylem diameter is 25 to 75 micrometers, and 1 micrometer is 1,000 nanometers. In botanical terms, we think of the stomata on the underside of leaves. Is this what is meant? It seems so, from what comes next:

As you move down the tree the pressure increases up to atmospheric at the roots. So you can have a large pressure difference between the top and the bottom of the tree because the pressure at the top is so negative.

I’m still not quite sure how this might be so, and perhaps for that reason the rest of the explanation drifts away from me, though I’m sure it’s trustworthy, and it certainly helps explain why transpiration is indeed an essential part of the entire water movement explanation. But I’ll continue the explanation together with any questions I can come up with. Derek Muller, our Veritasium creator, now asks himself, shouldn’t the water boil at this high negative pressure?

Changing phase from liquid to gas (boiling) requires activation energy. What is this? It’s often defined as the minimum energy required to set off a chemical reaction:

And that can come in the form of a nucleation site like a tiny air bubble. That’s why it’s so important that the xylem tubes contain no air bubbles. Unlike a straw they’ve been water-filled from the start. This way, water remains in the metastable liquid state when it really should be boiling.

Slow down, two more terms are introduced here, a nucleation site and a metastable state. A nucleation site is basically a site where a phase change can begin, and start to spread, as in crystallisation from a solution. In order for water to boil, it has to start to boil somewhere – which is a molecular change. At this site, aka the nucleator, the opportunity for another, freer molecular arrangement (a gas) becomes available, and this will communicate itself to surrounding molecules. Okay, not the best explanation, but it helps me. For a better explanation you should go to the Khan Academy – and so should I. A metastable state, and I quote, is an excited state of an atom or other system with a longer lifetime than the other excited states. However, it has a shorter lifetime than the stable ground state. … A large number of excited atoms are accumulated in the metastable state (Optics 101).

This explains why Muller says the water high in the xylem ‘really should be boiling’, or that it should be in a gaseous state, for that would be its ground state under normal circumstances.

So that’s as far as I can go. It’s been an odyssey for me as well as it was for Muller, and I’m definitely not as sure on it as I could/should be, but I’ve made a lot of headway, and it really is amazing to think of what not only trees but the plants on my balcony ‘garden’ are doing all the time – sucking water through their bodies and into the atmosphere…

 

Written by stewart henderson

February 22, 2018 at 9:42 am

How do trees transport water such long distances? Part 2: the mechanism remains a mystery (to me)

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and I still haven’t found what I’m looking for…

So scientists have learned a lot, though not everything, about water’s travels from soil to leaf in a plant or tree. It’s a fascinating story, and I’m keen to learn more. But the real mystery for me is about energy. As the excellent Nature article, upon which I’m mostly relying, points out, animals have a pump-based circulatory system to distribute nutrients, oxygen and so forth, but plants are another matter, or another form of organised matter.

I actually posed two questions in my last post. How do plants – and I think I should specify trees here, because the massive distance between the soil and their top leaves makes the problem more dramatic – move water such large distances, and how do they know they have to transport that water and how much water to transport?

So let’s look at the Nature Education explanation:

The bulk of water absorbed and transported through plants is moved by negative pressure generated by the evaporation of water from the leaves (i.e., transpiration) — this process is commonly referred to as the Cohesion-Tension (C-T) mechanism. This system is able to function because water is “cohesive” — it sticks to itself through forces generated by hydrogen bonding. These hydrogen bonds allow water columns in the plant to sustain substantial tension (up to 30 MPa when water is contained in the minute capillaries found in plants), and helps explain how water can be transported to tree canopies 100 m above the soil surface.

Notice how we’re again returning to the explanations questioned by Wohlleben – transpiration and capillary action. But we’re introduced to something new – the C-T mechanism. The thesis is that water’s cohesiveness through hydrogen bonding creates a tension (the tension that makes for capillary action) that enables water to be shifted up to 100 metres – all because of the minuteness of capillaries found in plants. And trees? Somehow, I just can’t see it. Perhaps the key is in the phrase ‘helps explain’.  There must surely be more to this. The thesis also mentions ‘negative pressure’ generated by transpiration. This is the signalling I wrote about before. Somehow the plant’s chemistry recognises that there’s an imbalance, and of course this happens in all living things, regardless whether they have a complex nervous system. So maybe there’s no need to worry about ‘knowing’. All living organisms respond to their ever-changing environment by altering their internal chemistry, by opening or closing barriers, by selectively adding or subtracting nutrients, and there are unknowns everywhere about precisely how they do that. It’s a kind of organised chemistry that seems like everyday magic from the outside, whether we’re focusing on a beech tree or our own intestines.

The C-T mechanism is only new to me I should add. It can actually be traced back to 1727 and a book by Stephen Hales, in which he pointed out that without what he called perspiration the water in a plant would stagnate, and that it was also required to allow for the capillary movement of water, because ‘the sap-vessels are so curiously adapted by their exceeding fineness, to raise [water] to great heights, in a reciprocal proportion to their very minute diameters’. But this ‘reciprocal proportion’, according to Wohlleben, as quoted in the last post, can only account for a maximum of 3 feet of upward force in ‘even the narrowest of vessels’.

The water transport system, referred to in the last post as the water potential difference or gradient, also has another name, the Soil Plant Atmosphere Continuum (SPAC). I also mentioned something about an ‘apoplastic pathway’. Water enters the tree by the roots, which are divided and subdivided much like branches and twigs above-ground, with the thinnest examples being the fine root hairs. Water enters through the semi-permeable cell walls by osmosis. Cell-to-cell osmosis carries the water deeper into the root system, and thence into an apoplastic pathway. According to this video, this pathway provides an uninterrupted flow of water (no cell wall barriers) which allows a mass flow ‘due to the adhesive and cohesive properties of water’. This is the cohesion-tension theory again. Apparently, due to evaporation, a tension is created in the apoplast’s continuous stream, leading to this ‘mass flow’.

This makes absolutely no sense to me. What I’m so far discovering is that it’s pretty hard to start from scratch as an amateur/dilettante and get my head around all this stuff, and in my reading and video-watching I’ve yet to find a straightforward answer to the how of long distance, fast transport of water in plants/trees – there probably isn’t one.

I’ll try again after a diet of videos – so far I’ve found a large number of videos in Indian English, and their accents defeat me, I’m sad to say. No transcripts available. Meanwhile, I’ve compiled a little glossary (from various sources) to help myself…

apoplast – within plants, the space outside the plasma membrane within which material can diffuse freely. It is interrupted by the Casparian strip in roots, by air spaces between plant cells and by the plant cuticle.

Casparian stripa band of cell wall material deposited in the radial and transverse walls of the endodermis, which is chemically different from the rest of the cell wall – the cell wall being made of lignin and without suberin – whereas the Casparian strip is made of suberin and sometimes lignin.

cortical cells – in plants, cells of the cortex, the outer layer of the stem or root of a plant, bounded on either side by the epidermis (outer) and the endodermis (inner).

exudation – An exudate is a fluid emitted by an organism through pores or a wound, a process known as exuding.

guttation – water loss, when water or sap collects (at times of low evaporation, dawn & dusk), at tips of grass, herbs (not to be confused with dew, caused by condensation).

hydrostatic pressure – the pressure exerted by a fluid at equilibrium at a given point within the fluid, due to the force of gravity. This increases in proportion to depth measured from the surface because of the increasing weight of fluid exerting downward force from above.

lignin – a class of complex organic polymers that form important structural materials in the support tissues of vascular plants and some algae. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily.

osmosis – the movement of water from an area of high to low concentration through a semi-permeable membrane. ‘Pumps’ in the cell membrane transport the specific ions into the cell which means water moves in by osmosis thus maintaining hydrostatic pressure.

phloem – the living tissue that transports the soluble organic compounds made during photosynthesis and known as photosynthates, in particular the sugar sucrose, to parts of the plant where needed. This transport process is called translocation.

plasmodesmata – narrow threads of cytoplasm that pass through the cell walls of adjacent plant cells and allow communication between them.

root pressure – the transverse osmotic pressure within the cells of a root system that causes sap to rise through a plant stem to the leaves. Root pressure occurs in the xylem of some vascular plants when the soil moisture level is high either at night or when transpiration is low during the day

sap – a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.

suberin – an inert impermeable waxy substance present in the cell walls of corky tissues. Its main function is as a barrier to movement of water and solutes.

symplast – the network of cytoplasm of all cells interconnected by plasmodesmata. The movement of water occurs from one cell to another through plasmodesmata

tracheid – a type of water-conducting cell in the xylem which lacks perforations in the cell wall.

vascular (plants) – also known as tracheophytes and also higher plants, form a large group of plants (over 300,000 accepted known species) that are defined as those land plants that have lignified tissues (the xylem) for conducting water and minerals throughout the plant.

xylem – one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to shoots and leaves, but it also transports some nutrients.

 

On the Trump’s downfall. What a memo. One wonders if the DoJ is running out of patience with the wannabe dictator and his imbecilities, which may bring things to a head sooner rather than later. But those in the know say that Mueller is always thorough and unlikely to be distracted, so I shouldn’t project my own impatience onto him. Dog give me strength to suffer the horrorshow for a while longer.

 

Written by stewart henderson

February 5, 2018 at 3:48 pm

Posted in biology, botany

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the battle for and against electric vehicles in Australia, among other things

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Toyota Camry hybrid – hybrids are way outselling pure EVs here, probably due to range anxiety and lack of infrastructure and other support

I’ve probably not been paying sufficient attention, but I’ve just learned that the Federal Energy minister, Josh Frydenberg, is advocating, against the naysayers, for government support to the EV industry. An article today (Jan 22) in The Australian has Frydenberg waxing lyrical about the future of EVs, as possibly being to the transport sector ‘what the iPhone has been to the communication sector’. It’s a battle the future-believers will obviously win. A spokesman for the naysayers, federal Liberal Party MP and AGW-denier Craig Kelly, was just on the gogglebox, mocking the idea of an EV plant in Elizabeth here in South Australia (the town I grew up in), sited in the recently abandoned GM Holden plant. His brilliantly incisive view was that since Holdens failed, a future EV plant was sure to fail too. In other words, Australians weren’t up to making cars, improving their practice, learning from international developments and so forth. Not exactly an Elon Musk attitude.

The electric vehicles for Elizabeth idea is being mooted by the British billionaire Sanjeev Gupta, the ‘man of steel’ with big ideas for Whyalla’s steelworks. Gupta has apparently become something of a specialist in corporates rescues, and he has plans for one of the biggest renewables plants in Australia – solar and storage – at Whyalla. His electric vehicle plans are obviously very preliminary at this stage.

Critics are arguing that EVs are no greener than conventional vehicles. Clearly their arguments are based on the dirty coal that currently produces most of the electricity in the Eastern states. Of course this is a problem, but of course there is a solution, which is gradually being implemented. Kiata wind farm in Western Victoria is one of many small-to medium-scale projects popping up in the Eastern states. Victoria’s Minister for Energy, Environment and Climate Change (an impressive mouthful) Lily D’Ambrosio says ‘we’re making Victoria the national leader in renewable energy’. Them’s fightin words to we South Aussies, but we’re not too worried, we’re way ahead at the moment. So clearly the EV revolution is going hand in hand with the renewable energy movement, and this will no doubt be reflected in infrastructure for charging EVs, sometimes assisted by governments, sometimes in spite of them.

Meanwhile, on the global scale, corporations are slowly shuffling onto the renewables bandwagon. Renew Economy has posted a press release from Bloomberg New Energy Finance, which shows that corporations signed a record volume of power purchase agreements (PPAs) for clean energy in 2017, with the USA shuffling fastest, in spite of, or more likely because of, Trump’s dumbfuckery. The cost-competitiveness of renewables is one of the principal reasons for the uptick, and it looks like 2018 will be another mini-boom year, in spite of obstacles such as reducing or disappearing subsidies, and import tariffs for solar PVs. Anyway, the press release is well worth a read, as it provides a neat sketch of where things are heading in the complex global renewables market.

Getting back to Australia and its sluggish EV market, the naysayers are touting a finding in the Green Vehicle Guide, a federal government website, which suggested that a Tesla powered by a coal-intensive grid emitted more greenhouse gas than a Toyota Corolla. All this is described in a recent SMH article, together with a 2016 report, commissioned by the government, which claimed that cars driven in the Eastern states have a “higher CO2 output than those emitted from the tailpipes of comparative petrol cars”. However, government spokespeople are now admitting that the grid’s emission intensity will continue to fall into the future, and that battery efficiency and EV performance are continuously improving – as is obvious. Still, there’s no sign of subsidies for EVs from this government, or of future penalties for diesel and petrol guzzlers. Meanwhile, the monstrous SUV has become the vehicle of choice for most Australians.

While there are many many honourable exceptions, and so many exciting clean green projects up and running or waiting in the wings, the bulk of Australians aren’t getting the urgency of climate change. CO2 levels are the highest they’ve been in 15 million years (or 3 million, depending on website), and the last two years’ published recordings at Mauna Loa (2015 and 2016) showed increases in atmospheric CO2 of 3PPM for each year, for the first time since recording began in 1960 (when it was under 1PPM). This rate of CO2 growth, apparently increasing – though with variations due largely to ENSO – is phenomenal. There’s always going to be a see-saw in the data, but it’s an ever-rising see-saw. The overall levels of atmospheric CO2 are now well above 400PPM. Climate Central describes these levels as ‘permanent’, as if humans and their effects will be around forever – how short-sighted we all are.

The relationship between atmospheric CO2 and global warming is fiendishly complex, and I’ll try, with no doubt limited success, to tackle it in future posts.

 

Mustn’t forget my update on Trump’s downfall: the Mueller team has very recently interviewed A-G Sessions, who’s been less than honest about his meetings with Russians. Nobody knows what Sessions was asked about in in his lengthy session (haha) with the inquirers, but he’s a key figure when it comes to obstruction of justice as well as conspiracy. Word now is that Trump himself will be questioned within weeks, which could be either the beginning of the end, or just the end. Dare to hope.

 

Written by stewart henderson

January 26, 2018 at 10:26 am