Climate Change and Political inertness

Since the season of goodwill and general cheerfulness is approaching, it seems wrong to present even more bad news for this rather dismal year, yet we cannot hide from it, The problem was presented in Nature ( https://doi.org/10.1038/d41586-021-03758-y  and relates to the Thwaites glacier. This glacier flows off the Antarctic continent into the Southern ocean. The glacier is 120 kilometers wide and about two thirds of this flows into the Southern Ocean, but one third runs into its eastern ice shelf. Here, the flow grinds to a halt because the ice out at sea hits an underwater mountain that is about 40 kilometres offshore. The Mountain is stopping the ice from flowing.

Unfortunately, thanks to the warmer water flowing underneath, that part of the glacier is becoming unstuck from the mountain, and this is causing cracking and fracturing across parts of the ice shelf. The fractures are propagating through the ice at several kilometres per year, and are heading towards thinner ice, which may lead to the whole lot shattering. To add to the problem there is tidal flexing as the glacier starts to separate from the rock and the “up and down” movement with the tides causes the glacier to flex further upstream, including where it is over land. Because of this flexing, warm water from the Southern Ocean could make its way beneath the glacier more easily.

Current estimates are that this mass of ice over the water could shatter within five years, which would release an huge mass of icebergs into the Southern Ocean, and the whole glacier could start flowing much faster into the sea. That means sea level rise. Currently the Thwaites already loses around fifty billion tonnes of ice each year and causes 4% of global sea level rise. If this eastern ice shelf collapses, ice would flow three times faster into the sea. If the glacier were to collapse completely sea levels would rise 65 centimetres. The glacier itself is moving towards the sea at about a mile each year. This is a fairly fast moving glacier.

So, what do we do about it. In this case it is probably impossible to do much. There is no way to stop a glacier moving. The only possible thing to do to stop the sea level rise would be to somehow engineer more snow to fall further inland to Antarctica. Fifty billion tonnes of snow each year would cancel out the sea level rise, but we all know that is not about to happen any time soon. But not to worry. Senator Manchin does not believe in climate change as a hazard, and he will torpedo President Biden’s efforts to get the US to do something. This Senator wants to burn more coal, and this one man will torpedo everyone else’s limited efforts. So is the Senator right? No. We might not be able to stop the Thwaites, but there are worse problems downstream we can still stop if we act before they become activated. Of course, he is not alone. Australia is selling more coal, China is building more coal-foired power stations, Germany has turned of nuclear to burn lignite. A cartoon in our paper had it: the Devil was reading about our activities and he said, “Aw, no fun. They’re not even pretending to try now.”

The nature of the problem is what we call hysteresis. If you have an equilibrium, such as when there is no change of temperature in an object over time, this arises because the heat loss equals the heat input. Now, suppose you increase the heat input a little. Now we are out of equilibrium, but since the heat loss depends on the temperature what you expect is the temperature will rise to reach the equilibrium position corresponding to where the heat loss now equals the heat input. Unfortunately, it doesn’t quite work like that. Suppose I have a lump of iron, and I increase the amount of heat going into it. The surface may well get warmer, but heat then starts flowing into the inside of the object. It takes time before the object reaches the new temperature. With something like ice, it is worse. The ice will warm, but once it gets to its melting point the increased heat flowing in starts to melt the ice. The ice stays at the same temperature. If we increase the heat flow inwards there is no change, other than the ice melts faster. Then, when it has all melted, suddenly the temperature starts to increase quickly.

To some extent, that is what has happened on our planet. Our greenhouse effect has been slowing the heat loss to space, and since the heat input remains the same, effectively the system is absorbing more heat. However, to start with all that happened was the surface of the oceans warmed up and some ice melted. So we ignored the problem because we observed no change in temperature, and poured more heat in. All that did was warm more water and melt more ice. The problem then is that we have now reached the point where the increase in heat that we are pouring into the Earth is starting to reach the point where the effects that absorbed heat without altering our temperature too much have now reached the end of their capacity. We are now going to make major changes to the planet, and we cannot stop them because the forces are already in place to generate far more heat.

Another characteristic of hysteresis is you cannot reverse what you have done simply by stopping increasing the heat input. Because the ice is melting because the water is above its freezing point, if we stopped adding heat now and stopped all greenhouse emissions, the oceans are still warm and the melting continues. However, there are thresholds. One calculation (Nature 585 (2020) p 538) indicated that for every degree of global temperature rise up to 2 degrees above pre-industrial levels will lead to 1.3 metres of sea-level rise. Between 2 – 6 degrees of warming it doubles to 2.4 metres per degree, and between 6 – 9 degrees, we get an extra 10 meters per degree. Further, the nature of hysteresis is that this is irreversible. If we want to turn it around we have to reduce global temperatures to one degree below what they were in 1850.

With that dismal thought, I wish you all a very Merry Christmas and all the best for 2022. This will be my last post for the year, and as usual I shall resume in mid-January. Finally, there are still my ebooks on the Smashwords sale.

Ebook Discounts at Smashwords

From December 17 – January 1, my ebooks at Smashwords will be significantly discounted. The fictional ebooks, which are thrillers and, similar to Andy Weir, with real science in the background, include:

Puppeteer:  A technothriller where governance is breaking down due to government debt, and where a terrorist attack threatens to kill tens to hundreds of millions of people and destroy billions of dollars worth of infrastructure.

http://www.smashwords.com/books/view/69696

‘Bot War:  A technothriller set about 8 years later, a more concerted series of terrorist attacks made by stolen drones lead to partial governance breaking down.

Smashwords    https://www.smashwords.com/books/view/677836

Troubles. Dystopian, set about 10 years later still, the world is emerging from anarchy, and there is a scramble to control the assets. Some are just plain greedy, some think corporate efficiency should rule, some think the individual should have the right to thrive, some think democracy should prevail as long as they can rig it, while the gun is the final arbiter.

https://www.smashwords.com/books/view/174203

Spoliation. A thriller set about asteroid mining, where some of the miners mysteriously disappear. Then someone tries tο weaponise a large asteroid. A story of greed, corruption and honour, combining science and visionary speculation that goes from the high frontier to outback Australia.

https://www.smashwords.com/books/view/1090447

There is also the non-fictional “Biofuels”. This gives an overview of the issues involved in biofuels having an impact on climate change. Given that electric vehicles, over their lifetime probably have an environmental impact equivalent to or greater than the combustion motor, given that we might want to continue to fly, and given that the carbon from a combustion exhaust offers no increase in atmospheric carbon levels if it came from biofuel, you might be interested to see what potential this has. The author was involved in research on this intermittently (i.e. when there was a crisis and funding was available) for over thirty years. https://www.smashwords.com/books/view/454344

What Happens Inside Ice Giants?

Uranus and Neptune are a bit weird, although in fairness that may be because we don’t really know much about them. Our information is restricted to what we can see in telescopes (not a lot) and the Voyager fly-bys, which, of course, also devoted a lot of attention to the Moons, since a lot of effort was devoted to images. The planets are rather large featureless balls of gas and cloud and you can only do so much on a “zoom-past”. One of the odd things is the magnetic fields. On Earth, the magnetic field axis corresponds with the axis of rotation, more or less, but not so much there. Earth’s magnetic field is believed to be due to a molten iron core, but that could not occur there. That probably needs explaining. The iron in the dust that is accreted to form planets is a fine powder; the particles are in the micron size. The Earth’s core arises because the iron formed lumps, melted, and flowed to the core because it is denser. In my ebook “Planetary Formation and Biogenesis” I argue that the iron actually formed lumps in the accretion disk. While the star was accreting, the region around where Earth is reached something like 1600 degrees C, above the melting point of iron, so it formed globs. We see the residues of that in the iron-cored meteorites that sometimes fall to Earth. However, Mars does not appear to have an iron core. Within that model, the explanation is simple. While on Earth the large lumps of iron flowed towards the centre, on Mars, since the disk temperature falls off with distance from the star, at 1.5 AU the large lumps did not form. As a consequence, the fine iron particles could not move through the highly viscous silicates, and instead reacted with water and oxidised, or, if you prefer, rusted.

If the lumps that formed for Earth could not form at Mars because it was too far away from the star, the situation was worse for Uranus. As with Mars, the iron would be accreted as a fine dust and as the ice giants started to warm up from gravitational collapse, the iron, once it got to about 500 degrees Centigrade, would rapidly react with the water and oxidise to form iron oxides and hydrogen. Why did that not happen in the accretion disk? Maybe it did, and maybe at Mars it was always accreted as iron oxides, but by the time it got to where Earth is, there would be at least ten thousand times more hydrogen than iron, and hot hydrogen reduces iron oxide to iron. Anyway, Uranus and Neptune will not have an iron core, so what could generate the magnetic fields? Basically, you need moving electric charge. The planets are moving (rotating) so where does the charge come from?

The answer recently proposed is superionic ice. You will think that ice melts at 0 degrees Centigrade, and yes, it does, but only at atmospheric pressure. Increase the pressure and it melts at a lower temperature, which is how you make snowballs. But ice is weird. You may think ice is ice, but that is not exactly correct. There appear to be about twenty ices possible from water, although there are controversial aspects because high pressure work is very difficult and while you get information, it is not always clear about what it refers to. You may think that irrespective of that, ice will be liquid at the centre of these planets because it will be too hot for a solid. Maybe.

In a recent publication (Nature Physics, 17, 1233-1238 November 2021) authors studied ice in a diamond anvil cell at pressures up to 150 GPa (which is about 1.5 million times greater than our atmospheric pressure) and about 6,500 degrees K (near enough to Centigrade at this temperature). They interpret their observations as there being superionic ice there. The use of “about” is because there will be uncertainty due to the laser heating, and the relatively short times up there. (Recall diamond will also melt.)

A superionic ice is proposed wherein because of the pressure, the hydrogen nuclei can move about the lattice of oxygen atoms, and they are the cause of the electrical conduction. These conditions are what are expected deep in the interior but not at the centre of these two planets. There will presumably be zones where there is an equilibrium between the ice and liquid, and convection of the liquid coupled with the rotation will generate the movement of charge necessary to make the magnetism. At least, that is one theory. It may or may not be correct.

Your Water Came from Where?

One interesting question when considering why Earth has life is from where did we get our water? This is important because essentially it is the difference between Earth and Venus. Both are rocky planets of about the same size. They each have similar amounts of carbon dioxide, with Venus having about 50% more than Earth, and four times the amount of nitrogen, but Venus is extremely short of water. If we are interested in knowing about whether there is life on other planets elsewhere in the cosmos, we need to know about this water issue. The reason Venus is hell and Earth is not is not that Venus is closer to the Sun (although that would make Venus warmer than Earth) but rather it has no water. What happened on Earth is that the water dissolved the CO2 to make carbonic acid, which in turn weathered rocks to make the huge deposits of lime, dolomite, etc that we have on the planet, and to make the bicarbonates in the sea.

One of the more interesting scientific papers has just appeared in Nature Astronomy (https://doi.org/10.1038/s41550-021-01487-w) although the reason I find it interesting may not meet with the approval of the authors. What the authors did was to examine a grain of the dust retrieved from the asteroid Itokawa by the Japanese Space agency and “found it had water on its surface”. Note it had not evaporated after millions of years in a vacuum. The water is produced, so they say, by space weathering. What happens is that the sun sends out bursts of solar wind which contains high velocity protons. Space dust is made of silicates, which involve silica bound to four oxygen atoms in a tetrahedron, and each oxygen atom is bound to something else. Suppose, for sake of argument, the something else is a magnesium atom. A high energy hydrogen nucleus (a proton) strikes it and makes SiOH and, say Mg+, with the Mg ion and the silicon atom remaining bound to whatever else they were bound to. It is fairly standard chemistry that 2SiOH → SiOSi plus H2O, so we have made water. Maybe, because the difference between SiOH on a microscopic sample of dust and dust plus water is rather small, except, of course, Si-OH is chemically bound to and is part of the rock, and rock does not evaporate. However, the alleged “clincher”: the ratio of deuterium to hydrogen on this dust grain was the same as Earth’s water.

Earth’s water has about 5 times more deuterium than solar hydrogen, Venus about a hundred times. The enhancement arises because if anything is to break the bond in H-O-D, the hydrogen is slightly more probable to go because the deuterium has a slightly stronger bond to the oxygen. Also, being slightly heavier, H-O-D is slightly less likely to get to the top of the atmosphere.

So, a light bulb moment: Earth’s water came from space dust. They calculate that this would produce twenty litres of water for every cubic meter of rock. This dust is wet! If that dust rained down on Earth it would deliver a lot of water. The authors suggest about half the water here came that way, while the rest came from carbonaceous chondrites, which have the same D/H ratio.

So, notice anything? There are two problems when forming a theory. First, the theory should account for everything of relevance. In practice this might be a little much, but there should be no obvious problems. Second, the theory should have no obvious inconsistencies. First, let us look at the “everything”. If the dust rained down on the Earth, why did not the same amount rain down on Venus? There is a slight weakness in this argument because if it did, maybe the water was largely destroyed by the sunlight. If that happened a high D/H ratio would result, and that is found on Venus. However, if you accept that, why did Earth’s water not also have its D/H ratio increased? The simplest explanation would be that it did, but not to extent of Venus because Earth had more water to dilute it. Why did the dust not rain down on the Moon? If the answer is the dust had been blown away by the time the Moon was formed, that makes sense, except now we are asking the water to be delivered at the time of accretion, and the evidence on Mars was that water was not there until about 500 million years later. If it arrived before the disk dust was lost, then the strongest supply of water would come closest to the star, and by the time we got to Earth, it would be screened by inner dust. Venus would be the wettest and it isn’t.

Now the inconsistencies. The strongest flux of solar wind at this distance would be what bombards the Moon, and while the dust was only here for a few million years, the Moon has been there for 4.5 billion years. Plenty of time to get wet. Except it has not. The surface of the dust on the Moon shows this reaction, and there are signs of water on the Moon, especially in the more polar regions, and the average Moon rock has got some water. But the problem is these solar winds only hit the surface. Thus the top layer or so of atoms might react, but nothing inside that layer. We can see those SiOH bonds with infrared spectroscopy, but the Moon, while it has some such molecules, it cannot be described as wet. My view is this is another one of those publications where people have got carried away, more intent on getting a paper that gets cited for their CV than actually stopping and thinking about a problem.

Quantum weirdness, or not?

How can you test something without touching it with anything, even a single photon? Here is one of the weirder aspects of quantum mechanics. First, we need a tool, and we use the Mach-Zehnder interferometer, which is illustrated as follows:

There is a source that sends individual photons to a beam splitter (BS1), which divides the beam into two sub-beams, each of which proceed to a mirror that redirects them to meet at another beam splitter (BS2). The path lengths of the two sub-beams are exactly the same (in practice a little adjustment may be needed to get this to work). Each sub-beam (say R and T for reflectance and transmitted at BS1) is reflected once by a mirror. When reflected, they sustain a phase shift of π, and R sustains such a phase shift at BS1. At BS2, the waves going to D1 both have had two reflections, so both have had a phase shift of 2π and they interfere constructively, therefore D1 registers the photon arrival. However, it is a little more complicated at D2. The original beams T and R that would head towards D2 have a net phase difference of π within the beam splitter, so they destructively interfere and the original beam R continues in the direction of net constructive interference hence only detector D1 registers. Now, suppose we send through one photon. At BS1, it seems the wave goes both ways but the photon, which acts as a particle, can only go one way. You get exactly the same result because it does not matter which way the photon goes; the wave goes both ways but the phase shift means only D1 registers.

Now, suppose we block one of the paths? Now there is no interference at BS2 so both D1 and D2 register equally. That means we can detect an obstruction on the path R even if no photon goes along it.

Now, here is the weird conclusion proposed by Elitzer and Vaidman [Foundations of Physics 23, 987, (1992)]. Suppose you have a large supply of bombs, but you think some may be duds. You attach a sensor to each bomb wherein if one photon hits it, it explodes. (It would be desirable to have a high energy laser as a source, otherwise you will be working in the dark setting this up.) At first sight all you have to do is shine light on said bombs, but at the end all you will have are duds, the good ones having blown up. But suppose we put it in the arm of such an interferometer so that it blocks the photon. Half the time a photon will strike it and it will explode if it is good, but consider the other half. When the photon gets to the second beam splitter, the photon has a 50% chance of going to either D1 or D2. If it goes to D1 we know nothing, but if it goes to D2 we know the photon went to the bomb. If the bomb was any good it exploded, so if it did not explode we know it was a dud. So if the bomb is good, the probability is ¼ that we shall learn without destroying it, ½ that we destroy it, and ¼ that we don’t know. In this case we send a second photon and continue until we get a hit at D2, then stop. The probability that we can detect the bomb without sensing it with anything now ends up at 1/3. So we end up keeping 1/3 of our bombs and locate all the duds.

Of course, this is a theoretical prediction. As far as I know, nobody has ever tested bombs, or anything else for that matter, this way. In standard quantum mechanics this is just plain weird. Of course, if you accept the pilot wave approach of de Broglie or Bohm, or for that matter my guidance wave version, where there is actually a physical wave other than the wave being a calculating aid, it is rather straightforward. Can you separate these versions? Oddly enough, yes, if reports are correct. If you have a version of this with an electron, the end result is that any single electron has a 50% chance of firing each detector. Of course, one electron fires only one detector. What does this mean? The beam splitter (which is a bit different for particles) will send the electron either way with a 50% probability, but the wave appears to always follow the particle and is not split. Why would that happen? The mathematics of my guidance wave require the wave to be regenerated continuously. For light, this happens from the wave itself, from Maxwell’s theory of light being an oscillation of electromagnetic waves. The oscillation of the electric field causes the next magnetic oscillation, and vice versa. But an electron does not have this option, and the wave has to be tolerably localised in space around the particle.

Thus if the electron version of this Mach Zehnder interferometer does do what the reference I say claims it did (unfortunately, it did not cite a reference) then this odd behaviour of electrons shows that the wave function for particles at least cannot be non-local (or the beam splitter did not work. There is always an alternative conclusion to any single observation.)