I've done a lot more Googling and reading up on ozone depletion theory since I stumbled across it a couple of weeks ago. It seems to be a very plausible and mercifully simple explanation why the troposphere (lower atmosphere) has warmed a bit and the upper atmosphere (stratosphere) has cooled a lot over the past forty years. It might be correct, it might be nonsense, but it does appear to be the most likely explanation and the most worthy of investigation and exploration.
Most of the hits you get if you search the terms 'ozone depletion' or 'stratosphere cooling' are Alarmist websites and blogs (for example Skeptical Science and Science of Doom), all of which greatly play down the effects of ozone depletion.
Nonetheless, stratospheric cooling is A Thing, and the Alarmists see themselves obliged to explain it in terms of CO2 and radiation (for no obvious reason).
Do your own reading up and make up your own mind, but IMHO, here are the six impossible, or at least mutually contradictory, things Alarmists have to believe before breakfast:
1. CO2 'traps' some of the infra red radiation (IR) emitted upwards by land, oceans and clouds in the troposphere
As a result, the troposphere warms. To believe this, you have to ignore the fact that radiation does not have a temperature and is not thermal energy. Radiation has to hit something first, cease to be radiation and be converted from radiation to thermal energy ('energy is not created or destroyed' etc). You also have to ignore the fact that the total IR emitted to space is equal to the total IR emitted by land, oceans and clouds (give or take a couple of per cent, depending which assumptions you make - nobody knows and it's impossible to prove or disprove either way).
And as a secondary result, there is less radiation going up into the stratosphere, so the stratosphere cools. To believe this, you have to ignore the fact that the stratosphere is warmed from above by UV-C and UV-B interacting with oxygen (O2) and ozone (O3). Accepted science is that the high energy UV radiation split molecules, so the energy is converted to chemical energy (endothermic reaction), and when O and O2 recombine to form O3, the chemical energy is converted to thermal energy (exothermic reaction). There appears to be little interchange of thermal energy (whether by convection or radiation) between troposphere and stratosphere. That is why the temperature falls to its lowest at the tropopause (the boundary layer between the two).
2. The effect of more CO2 is to push the 'effective emitting altitude' (henceforth abbreviated to EEA to save me typing it out in full every time) upwards
This is a more sophisticated Alarmist theory than simple 'trapping'. It dismisses the 'trapping' idea and says IR at certain frequencies can only escape to space if the CO2 above it is less than a certain threshold in terms of density. CO2 is a fairly constant proportion of the atmosphere all the way up (about 1/25 of one percent) but the density of the atmosphere goes down as you go higher, and so does CO2 density per unit volume. Only IR emitted (by CO2 itself, natch) at or above the EEA at which CO2 density (in terms of CO2 per unit volume) is at that certain threshold can get to space. So more CO2 means the EEA is at a higher altitude.
This theory seems to accept the gravito-thermal effect aka the lapse rate. It also assumes that temperature and hence IR emitted at the EEA is a constant, so mathematically, if the threshold is one-sixth of a km higher (so it goes up from 5km to 5.166r km, for example), the surface is warmer by one-sixth of 6.5 K/km = about 1 degree warmer.
OK, but going back to 1, if the EEA is the same temperature and is allowing the same amount of IR to pass through and up, then the same applies to the tropopause (about 10 - 12 km up on average). If the stratosphere is warmed from below (which isn't true anyway), the lowest layer of the stratosphere would remain the same temperature. Which it clearly isn't doing. And we have a problem with the initial assumption that IR emitted at the EEA or tropopause goes out into space (instead of warming the stratosphere above it).
3. More CO2 in the stratosphere means it can radiate more out into space
According to this theory, nothing except GHGs can emit radiation (well apart from land, oceans and clouds, obvs), and certainly not nitrogen or oxygen/ozone. So you could heat air up as warm as you wished, and an IR thermometer would not be able to read a temperature. So all that thermal energy would be 'trapped' in the stratosphere. Along comes some extra CO2, which absorbs the thermal energy, turns it into radiation and biffs it up and out into space, it being above the EEA.
Or maybe it biffs some down into the troposphere to warm it a bit more. Apart from the fact that the net transfer of energy by radiation only goes from warmer to colder, and how does this radiation battle its way down through the EEA, which is impassable for radiation from below?
Either way, there is a neat double think that CO2 can 'trap' more radiation in the atmosphere and also emit more out into to space.
4. If 2 and 3 are true, then perhaps there are two EEA's?
Theory 2 is based on the fact the temperature falls as you go up through the tropopause. Push the EEA higher and that leads to surface warming. Perhaps Theory 3 is that there is a separate EEA for the stratosphere. If you push this higher, by reverse logic, everything below the new EEA cools down a bit?
5. The troposphere and stratosphere are in thermal equilibrium. Or not, as the case might be
If the temperature of the two layers tends to even out (by layers emitting radiation at each other), then we wouldn't see one warming and the other one cooling. So that blows a hole in Theory 1. Unless CO2 increases the lapse rate. Even though the main GHG, water vapour, reduces the lapse rate. On the other hand, Theory 2 assumes that there is a 'sort of' thermal equilibrium i.e. the temperature at the tropopause stays constant, but only a weak link, so below and above that altitude, each layer does its own independent thing. But if the stratosphere above does its own thing, is that not a tacit admission that it is warmed from above?
This obsession with radiation as the main form of energy transfer in the atmosphere is baffling anyway. Simple conduction and convection are far more important:
- To feel the temperature of a warm object (poorly child's forehead or hot water bottle), you have to actually touch it = conduction.
- Put your hand one inch to the side of a hot object (hot radiator, candle flame etc) = radiation; then put it one inch above that object = convection, which feels a lot warmer than one inch to the side.
- You have to get really hot, like a bonfire, for radiation to outweigh conduction, and even then, it's a lot hotter directly above it (convection + radiation) than to one side (radiation).
- The atmosphere is on the whole a lot cooler than a poorly child's forehead, so we can safely assume that the majority of thermal energy transfers are by conduction and convection.
6. CO2 has a 'fingerprint' which can be observed from space. Or not, as the case might be.
The Alarmists make great play of the fact that CO2 absorbs (and emits) IR at wavelength 16 microns (sometimes expressed as 667/cm or frequency a bit less than 10^13 Hz) and that if you measure terrestrial radiation with satellites, there is a noticeable gap at that wavelength. Theory 1 says that if there is more CO2, that missing bit will be larger. But if Theories 2 and 3 are correct, then the extra radiation emitted by CO2 in the stratosphere above the EEA (whichever one) ought to fill up that gap again.
As a final thought, let's imagine a counter-factual where CO2 levels are increasing (true) and the stratosphere were warming instead of cooling. Would the Alarmists shout 'slam dunk!' or would they accept it as evidence against their basic assumption that CO2 is to blame for everything? It's poor science to look for evidence to support 'your' theory or even 'a' theory. You have to remain open minded and look for evidence against as well as for, or accept that you were barking up the wrong tree.
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Anyway, happy New Year's Eve to anybody who has read this far. I think I shall celebrate Indian New Year in half an hour (6.30 GMT) and then call it a night.
Thursday, 31 December 2020
Can you believe in six impossible things before breakfast?
Posted by Mark Wadsworth at 17:58 8 comments
Labels: global warming, Logic, Science
Tuesday, 29 December 2020
I think that covid-19 has messed up my sense of smell
As was almost inevitable, one member of our family (Her Indoors) thought she had covid-19 so she applied for one of the postal tests, which came back positive a few days later.
Our little lass was insanely hot and ill for a day or two, so Her Indoors and the lass both went off to be tested locally (before the results of the first had one came back).
The lass is back to normal, our lad has been unaffected, but I also felt pretty crap for two or three days. I tried sniffing various things in the kitchen to see whether I had lost my sense of smell, that being one of the symptoms. I haven't lost my sense of smell* but it's definitely pretty messed up.
Most thing still smell the same to me, but there are a couple of things which I now can't smell at all; a couple of things which smell stronger (garlic) or where the smell seems to linger for longer; some things which smell weaker and a bit metallic (Foster's lager, even after I've poured it into a glass); and a couple of things which I normally like the smell of but which now smell rather unappetising to me (strawberry jelly, which also tastes metallic, the chocolate coating on biscuits, the peanuts in peanut cookies).
It turns out that this is a thing. Oh dear. And on the back of Her Indoors' positive test (the first one), I was sentenced to self-isolation until tomorrow inclusive. At least I can go out again for the New Year's Eve celebrations, lolz, was my initial thought.
To add to the confusion, somebody from the NHS rang Her Indoors yesterday and explained that actually the ten day quarantine starts when she first noticed symptoms, not the date of the test, so her quarantine period is now over and apparently this applies to all four of us. I wish she'd got that in writing, I don't think The Authorities will take kindly to this sort of waffle if they catch me breaking cover.
* For "smell" read "smell and/or taste", I just couldn't be bothered writing that each time.
Posted by Mark Wadsworth at 15:22 9 comments
Labels: Covid-19
Daily Mail firing on all cylinders
The Daily Mail sticks the house price straight into the headline to save its readers the bother of reading the article:
Grandfather’s five pet pugs who nipped at postman as he delivered a parcel to his £800,000 home are spared being put down after court hears he had Beware of the Dog sign up
Posted by Mark Wadsworth at 12:12 0 comments
Labels: Daily Mail, Dogs, House prices
Monday, 28 December 2020
Daily Mail on top form
From The Daily Mail:
Two grandparents known as the 'heart of the community' were killed in a fire at their farmhouse alongside their dog just hours after wishing their family happy Christmas.
Frank, 90 and Madeleine Dougharty, 86, were found alongside their dog Flash on Boxing Day morning at their farmhouse in the Sussex village of West Chiltington.
Emergency services were called to their £760,000 home at 9.10am after reports of a significant fire which has gutted their remote farmhouse.
Posted by Mark Wadsworth at 19:13 5 comments
Labels: Daily Mail, Death, House prices
Saturday, 26 December 2020
Shock horror - Excel only stores numbers to fifteen significant figures
This will probably turn out to be one of those things that everybody except me already knew, so I know I am setting myself up for a fall here.
I only noticed today when I was trying to enter a really long number. Excel records the first fifteen digits and replaces everything after than with zeroes. For sure, it was my Tesco Clubcard number, so I could save it as text, but that's not the point. It's an up to date version of Excel, by the way.
Ho hum.
Posted by Mark Wadsworth at 16:44 14 comments
Labels: Excel
Thursday, 24 December 2020
They don't own land, charge them money!
Money Week is weighing in with some advice for the Chancellor, too much debt? Just inflate it away.
However, they don't mention who'd be paying the debt in that case, yes, the poor bloody saver, with the real value of their savings decreasing year on year. Of course, if you own land, like all proper citizens should and are in debt, then it's win win. Your land goes up in value while your debts reduce.
'Twas ever thus, it's even in the Bible, Mark 4:25
"For whosoever hath, to him shall be given, and he shall have more abundance; but whosoever hath not, from him shall be taken away even that he hath."
Posted by Bayard at 13:55 11 comments
Wednesday, 23 December 2020
Science Deniers!
From climate.gov:
The ozone hole did not cause global warming
Because the ozone layer normally blocks ultraviolet (UV) light, an ozone hole allows more UV light than usual to reach the surface. However, the additional energy added to the Earth system from the ozone hole is so small that it couldn’t be responsible for the warming trend that’s been occurring.
How small? Well, the vast majority of sunlight is the light we can see—visible light with wavelengths of 400-700 nanometers. UV light is only about 8 percent of all sunlight to begin with, and the ozone layer and oxygen (both of which absorb UV) only permit a fraction of that to reach the surface. The additional amount of UV that the Antarctic ozone hole allows to reach the surface for a month or so each year is a small fraction of an already small amount of sunlight—too small to explain global warming.
1. The term "ozone hole" is not supposed to be taken literally! CFC gases have reduced the overall amount of ozone in the stratosphere everywhere, it is just most noticeable over the Antarctic at certain times of the year (and to a lesser extent over the Arctic). These are precisely the areas which are warming fastest, we are told - which supports the ozone depletion theory. So more UV-B gets down to the troposphere.
2. All this chit chat about frequencies is a side show, UV might only be 8% of all frequencies in incoming solar radiation. But energy is proportional to frequency and UV carries fifty times as much energy as much lower frequency/longer wavelength IR. And CO2 only absorbs/re-emits about one-tenth of the IR frequencies which the ground, oceans and clouds emit.
3. Whatever the clever radiation calculations might be (way beyond me), it is easier just to look at outcomes. The combined effect of UV-C, UV-B rays, oxygen and ozone in the stratosphere is enough to keep the average temperature at about 245 K via a series of endothermic reactions (which absorb energy from UV) and endothermic reactions (when O + O2 re-combine to O3 and give off heat). These reactions are tricky but are accepted physics. Without ozone, and assuming the lapse rate in the stratosphere is 9.8K/km (very dry), the average temperature would be 125K (I assume). So the UV/ozone effect warms the stratosphere by average 120K.
4. The mass of the air in the stratosphere is about one-quarter of the mass of the air in the troposphere (estimates vary). There is no hard dividing line - long haul jets fly quite happily in the lower stratosphere (and Joseph Kittinger got to the upper stratosphere by balloon and parachuted down again). It's just that the stratosphere is warmed from above by UV (so it's warmest at the top) and the troposphere is warmed from below by the ground/oceans and there is a gravito-thermal effect (so it's warmest at the bottom). The tropopause (the dividing line between troposphere and stratosphere) is just where temperatures are at a minimum and rise again (if you go up or down from there). This is why most atmospheres don't have a 'stratosphere' - there is no oxygen/ozone there to cause this effect.
5. So if there were no ozone in our stratosphere whatsoever, the UV/ozone effect would warm up the troposphere instead, by up to 30 degrees (one-quarter of the extra 120 K from 3 above). Ozone levels have dropped by (say) 10% since the 1970s, so 10% more UV-B is getting through. 10% x 30 degrees = 3 degrees. If one-third goes into warming the troposphere (and the rest into oceans or is otherwise dissipated), that's your one degree of atmospheric warming since the 1970s. It's clearly not a straight line relationship or anywhere that simple, but it's a good starting assumption.
6. Furthermore, car exhausts indirectly cause more ozone at low levels ("bad ozone" for this and other reasons), so there is plenty of ozone down here to catch the UV-B that now gets through and give off heat (another possible explanation for the urban heat island effect).
7. Further reading from an apparently unbiased source here.
Posted by Mark Wadsworth at 17:26 3 comments
Labels: global warming, ozone, Science
Tuesday, 22 December 2020
Looks like election fraud (but isn't)
Trump and Trump supporters have claimed that election results like this indicate election fraud:
In-person votes, counted first:
Trump - 39,200
Biden - 30,600
(A solid lead for Trump on 56%).
Postal votes, counted next:
Trump - 9,800
Biden - 20,400
(A massive lead for Biden on 71%)
Add them together and you get:
Trump - 49,000 votes
Biden - 51,000 votes
(A modest overall win for Biden on 51%).
The postal votes look a bit suspicious at first sight, but the actual explanation for this is that Trump advised his voters to vote in person. In his addled mind, he thought that postal votes for him would be deliberately lost in the system somehow, which is nonsense if you think about it for half a second. If corrupt election officials are prepared to shred postal Trump votes, why wouldn't they also be prepared to shred in-person Trump votes?
Biden did the sensible thing and told his voters to vote by post if possible (because of Covid) or in person if they preferred. Thus maximising the likelihood of any potential voter actually voting for him. There must have been some potential Trump voters who couldn't vote in person and didn't get round to voting by post either. Biden hedged his bets; it was a good strategy, regardless of Covid.
I can't find a breakdown of in-person and postal votes. It looks to be about 30% postal and 70% in person. So (let's assume), because of the candidates' exhortations, only 20% of Trump voters voted by post against 40% of Biden voters. Multiple those numbers up, assuming an overall narrow 51%-49% split in this particular area, and you get the results shown above.
It is not at all unusual for the Democrat candidate to win an election - they won four out the previous eight (or six out of eight if you go by popular vote and not by electoral college votes!). It is less usual for a sitting President to be voted out after one term, but it does happen i.e. Jimmy Carter (Dem) in 1980 and George H.W. Bush (Rep) in 1992. Hillary Clinton and Al Gore won the popular vote but lost the electoral college vote and were prepared to take it on the chin, rules are rules, so Trump is being a pathetic bad loser IMHO.
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The only conspiracy theory that I will subscribe to is that Pfizer weren't too happy with Trump's suggestion that drug prices be capped, which is why they delayed the announcement that their vaccine works until a few days after the election. Had they announced it shortly before the election, Trump would have got a real boost, seeing as it was his government which funded the research.
A similar thing happened to Julia Gillard in Australia, go figure. Rent seekers appear to have undue influence in elections; they have a lot of spare cash to spend on lobbying to make sure the rents continue to roll in. It's a Georgist thing, not a left-right thing.
Posted by Mark Wadsworth at 12:24 29 comments
Labels: Conspiracy, Donald trump, Election, Fraud, Maths
Sunday, 20 December 2020
Dark Matter and Dark Energy
Another nail in the coffin of Dark Matter and in favour of MOND and similar explanations here.
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Dark Energy is a different topic, and is a placeholder name for whatever causes galaxies to all be moving away from each other, unless they are fairly close and gravitational attraction over-rides it (by several orders of magnitude).
The clever scientists don't really know why this is happening, and there are different ways of calculating the rate of expansion which give different results (although they all seem to be within +/- 10% of each other).
I have spent a couple of weeks reading and trying to understand the page on Ozone Depletion Theory titled What is Electromagnetic Radiation?. I still only vaguely understand most of it, but this sentence grabbed my attention:
Light illuminates matter, but light itself is not visible, it is dark, until it interacts with matter. Given that Earth receives less than 5 x 10-8 % of Sun’s radiation, there must be a lot of dark energy in space that changes in time...
Woo hoo! That might be it. As a matter of fact, there is such a thing as solar sails, as popularised by Arthur C Clark, which use 'photon pressure' to gently but firmly accelerate a spacecraft. The rate of acceleration is painfully slow, but it is constant and cumulative, so they can get up to fair old speeds after a few years or a few decades.
So the logic is this: only a teeny-tiny amount of light emitted by a star hits solid matter in its own solar system or even its host galaxy; most of the light goes out into intergalactic space. A teeny-tiny amount of starlight leaving each galaxy hits solid matter in its own galaxy cluster, and so on and so forth. And in turn, each galaxy is being hit by light from all other galaxies; so they all act as giant solar sails.
As star light is nearly as old as the universe, those billions and billions of years worth of starlight from each galaxy (or galaxy cluster) is pushing each other galaxy (or galaxy cluster) gently but firmly away from itself and the cumulative effect is (just about) measurable (if you call ≈70 km/second per megaparsec distance measurable). By definition the rate of expansion must also be gently but firmly increasing.
Whether or not the universe has a "centre" (and I am prepared to accept that it doesn't, and it is not expanding into anything larger), this leads to its gradual expansion!
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This might be complete nonsense, but it's an entertaining thought at least. And seeing as its the only explanation I've ever seen, I'm going to stick with it for now until a better one comes along.
Posted by Mark Wadsworth at 13:28 15 comments
Friday, 18 December 2020
They own land! Give them money!
Spotted by TBH in This Is Money:
Second home owners who have registered their properties as businesses are set to land an £85million windfall from the Government's small business grant scheme.
Experts said the loophole allows the owners of second homes – many of which are registered in Devon, Cornwall, the Lake District and in seaside towns such as Scarborough – to register them as businesses as long as they 'make them available' to let for 140 days of the year* and take bookings for at least half of those days.
The practice, known as 'flipping', allows the property owners to pay business rates instead of council tax. It also means they are eligible for the Government's small business rates relief scheme, which means all but the largest properties pay little or no tax.
Owners are now also poised to collect a share – around £1,300 each – of £2.2billion support for small businesses closed due to coronavirus restrictions. According to commercial property adviser Altus Group, there are more than 62,000 properties in England which are classified as holiday homes and have been flipped** to become 'commercial' premises for tax purposes.
It is not the first time that the owners of second homes have benefited from Government handouts during the coronavirus crisis...
* The official name for this is "Furnished Holiday Lets" and is a set of insane (and fiddly) tax reliefs for second home owners.
** No doubt many of them will be flipped back from Business Rates to Council Tax when the Business Rates exemption ends - Council Tax is usually much lower. I wonder if they will ever publish that statistic.
Posted by Mark Wadsworth at 17:44 6 comments
Labels: Land Value Tax, Subsidies
Wednesday, 16 December 2020
Australian Xmas song
I'm dreaming of a hot Christmas
Just like the ones I'll always know
Where the trees are burning
And barbies turning
A huge pile of embers all a-glow
I'm dreaming of a hot Christmas
With every Christmas card I write
May your days be sunny and bright
With sun-block to keep skin nice and white.
Posted by Mark Wadsworth at 21:24 10 comments
Sunday, 13 December 2020
Another little mystery solved...
The Alarmists tie themselves in knots trying to explain why more CO2 = cooler stratosphere. I've tried understanding the explanation in that post. It's all highly circular and it's impossible to say whether it's correct or incorrect. Here's the chart from that post. Let's take it at face value (those are The Rules):
To cut a long story short, a pressure of 200 hPa is approx. equal to the height of the troposphere, the bit we are interested in. Below that it has warmed a bit (mainly pale green) and above that (the stratosphere) it has cooled a lot (mainly dark blue).
The ever reliable (as in 'reliably wrong') Skeptical Science explains Stratospheric Cooling and Tropospheric Warming by saying that CO2 'traps' low-energy infra red radiation emitted by the Earth's surface/oceans/clouds. The stratosphere is warmed by radiation emitted from below by the troposphere. If more infrared is 'trapped' in the troposphere, it can't warm the stratosphere.
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This of course contradicts the sophisticated 'top of troposphere' theory of Global Warming (from Science of Doom, skip down to sections 5 and 6). The TOT theory says that radiation emitted by and hence temperature at the top of the troposphere (the tropopause) are a constant. More CO2 pushes up the altitude of the tropopause.
This means that surface temperature goes up because surface temperature EQUALS temperature at the tropopause PLUS the gravity-induced lapse rate (it is nice to see an Alarmist accept that this exists and has nothing to do with Greenhouse Gases) MULTIPLIED BY the altitude of the tropopause. If that is true (I like to use their own arguments against them), then the amount of infrared reaching - and warming - the stratosphere from below is unchanged!
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So far, so bad. What is the more likely explanation?
The ozone depletion theory starts on the basis that ozone in the stratosphere converts high-energy solar ultraviolet radiation from above to thermal energy. This effect appears to be undisputed. (Even the hard core Alarmists at Science of Doom accept this, while simultaneously claiming that the stratosphere is warmed from below).
When ozone is depleted in the stratosphere (mainly because of CFC gases, which break down into Cl and Br gas, which in turn act as catalysts to break down O3 into O2; partly because of volcanic eruptions) it soaks up less of the ultraviolet energy and so doesn't warm up so much, and more ultraviolet energy gets down into the troposphere and heats up the ozone (and oxygen) there instead.
Game, set and match to the ozone depletion theory, methinks! A back of the envelope approximation says that a 4% fall in stratospheric ozone levels will increase tropospheric temperatures by about 1 degree, with a larger fall in stratospheric temperatures. This matches real life results since the 1970s and ties in with the above chart.
Posted by Mark Wadsworth at 17:19 17 comments
Labels: global warming, ozone
Saturday, 12 December 2020
"Global Warming is Caused by Ozone Depletion, Not Greenhouse Gases"
At last, a theory that stacks up!
See ozonedepletiontheory.info by Peter Ward for detailed explanations (and also very conscientious debunking of CO2-related theories as a bonus).
A lot of it is beyond my understanding, but on the whole it seems internally and externally consistent - temperature increases match CFC emissions much better than they match CO2 levels (that was the only thing that bothered me. Shouldn't you compare temperature increases with ozone levels?) - and very plausible. If we have to make do without spray cans and use different coolants in our fridges etc, I'm sure we can manage.
If reading is not your thing, his summary video (one hour long!) is here:
Posted by Mark Wadsworth at 14:56 11 comments
Labels: global warming, ozone
"The Alternative to Dark Matter May be General Relativity Itself"
From Astrobites. Here are the highlights:
For most astronomers, it is just common sense that dark matter accounts for approximately 85% of the matter in the universe. However, as long as the constituents of dark matter remain a mystery, some astronomers remain skeptical about our conventional understanding of dark matter. Recently, astronomer Alexandre Deur suggested that the theory of relativity itself may explain a phenomenon widely regarded as evidence for dark matter...
Modified Newtonian Dynamics, or MOND, for example, is the most discussed out of all the gravitation corrections to explain the missing mass problem (see this astrobite for further discussion of MOND vs. dark matter). It modifies the Newtonian gravitation law at low accelerations to enhance the effective gravitational attraction. Similarly, most of the other corrections require new descriptions of gravitation. But recently, as Deur proposes in this work, the effect of general relativity may account for the missing mass, without introducing any new corrections.
Yes, MOND is a bit of a fudge and an approximation, but the general approach is correct. It's a lot less of a fudge than inventing Dark Matter.
Generally, the predicted rotation of galaxies, as shown in Figure 1, is modelled by Newtonian dynamics. The rotation velocity is much smaller than the speed of light, especially at the outer part of the galaxy (typically v/c ≈ 0.1 % , where v is the velocity and c is the speed of light). Therefore, it is believed that a non-relativistic treatment is reasonable. However, this assumption could be challenged due to the effect of field self-interaction in general relativity. This effect depends on the mass only, and is independent of the rotation velocity, thus making a difference regardless of how fast the stars move in the galaxy. Deur shows that field self-interaction, which reveals the non-linear nature of general relativity, is in fact not negligible in the missing mass problem.
To demonstrate this, Deur uses the gravitational lensing formalism. While light travels in straight lines in flat space, it can be deflected in the presence of a gravitational field. In exactly the same way, the gravitational field lines connecting two parts of the galaxy are distorted by the background field. That is to say, the gravitational field is deformed by the total galactic mass. With the field lines distorted, the strength of the gravitation consequently changes.
Yup, gravity lenses itself, i.e. it focuses itself on the mass that created the gravity in the first place. You can guess this for yourself. Once they have worked out how and to what degree, they'll hopefully show that there was no need to invent Dark Matter, and the concept will be quietly shelved.
Posted by Mark Wadsworth at 13:28 5 comments
Labels: dark matter, gravity, Physics
Thursday, 10 December 2020
"There are only 10 kinds of people in this world...
... those who understand binary and those who don't."
Pinched from here
Posted by Mark Wadsworth at 22:39 12 comments
BBC is doing it again
From the BBC:
Will food be more expensive after 1 January?
Under WTO rules, supermarkets and other importers would have to pay substantial tariffs on many foods they bring in from the EU. Meat and dairy products face particularly high tariffs, but many other areas including fruit and vegetables would be also affected.
The BBC can't even be bothered to read its own summary of what the WTO is about:
The WTO was established in 1995, when it took over essentially the same functions from the General Agreement on Tariffs and Trade (Gatt), which came into force in 1948.
One of the motivations for creating the Gatt was a wish to dismantle the barriers to trade that had been erected between the two world wars. Most economists regard the establishment of these interwar trade barriers as misguided and say they probably aggravated the Great Depression of the 1930s...
A series of eight "rounds" of negotiations under the Gatt led to the progressive reduction in trade tariffs - taxes which are imposed only on imported products.
The minimum - and indeed the recommended - tariff imposed under WTO "rules" is precisely zero. Given how useless the UK government is, they might well impose tariffs on imported food, but this will be entirely self-inflicted. This will be the UK government waging economic warfare against its own people, and if the EU imposes tariffs on imports from businesses in the UK, that is them waging economic warfare against citizens of EU Member States.
Posted by Mark Wadsworth at 19:14 10 comments
Labels: EU, Propaganda, WTO
Wednesday, 9 December 2020
£77.40 well spent
The garage ironed out the little niggles - which they should have fixed when they had it in last week, but hey - and it now drives cheerful and chirpy again, just like an MX-5 should :-)
I also managed to get rid some of the rattling noises by going through the glove boxes and door pockets and removing all the biros and pencils the previous owner had left in it.
Posted by Mark Wadsworth at 19:53 3 comments
Labels: Cars
Monday, 7 December 2020
Songs on my Xmas playlist by release date
To summarise: the Golden Age of cheesy Xmas songs was from the 1940s to the 1960s, bang them out and hope for the best. The period 2007-2012 is skewed on my list because that's when Bob Dylan and Michael Bublé released their Xmas albums (both of them timeless classics). Apart from that, it's more evenly spread than you'd expect.
Posted by Mark Wadsworth at 20:04 7 comments
Saturday, 5 December 2020
MX5 - rear bumper repairs
Before:
After:
Some arsehole who was probably on his mobile decided to smash into my MX5 recently, and drove off without stopping. The damage was far worse than it looks in the 'before' picture.
Repair process as follows:
1. I bought all the replacement parts online for £1,500.
2. Luckily they were already assembled and attached to a very good condition* MX5 with the 1.8 engine and only half the mileage of my old one.
3. The local garage shifted across some good bits from the old one to the new one, did a bit of welding, new MOT etc; Suffolk Mazda came to collect the old one, paid me a very fair £350, bringing the net cost of the exercise down to £450, and that was the end of that.
* There are various niggles still to be sorted out. When I drove round for half an hour just now to keep the battery charged, the bloody handbrake light stayed on. I don't think the handbrake was actually on, because it drove OK and the brake disks weren't overly hot when I got back home, but it still doesn't 'feel' right somehow. It's not as lively as the old one with the 1.6 engine, which had 109 bhp ex-factory twenty years ago and was probably down to about 90 bhp when I bought it. Ah well, back to the menders it is, then.
Posted by Mark Wadsworth at 16:16 14 comments
Labels: Cars
Friday, 4 December 2020
More fun with 'missing radiation'
From Science of Doom, which is like Skeptical Science but hard core:
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Upwards Longwave Radiation
So let’s try and look at it again and see if starts to make sense. Here is the earth’s longwave energy budget – considering first the energy radiated up:
Of course, the earth’s radiation from the surface depends on the actual temperature. This is the average upwards flux. And it also depends slightly on the factor called “emissivity” but that doesn’t have a big effect.
The value at the top of atmosphere (TOA) is what we measure by satellite – again that is the average for a clear sky. Cloudy skies produce a different (lower) number.
These values alone should be enough to tell us that something significant is happening to the longwave radiation. Where is it going? It is being absorbed and re-radiated. Some upwards – so it continues on its journey to the top of the atmosphere and out into space – and some back downwards to the earth’s surface. This downwards component adds to the shortwave radiation from the sun and helps to increase the surface temperature.
As a result the longwave radiation upwards from the earth’s surface is higher than the upwards value at the top of the atmosphere.
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To make this easy for beginners, I have put their sleight of hand in bold.
1. We are agreed that overall average emissions from Earth out to space ≈ 239 W/m2.
2. For sake of argument, I accept their readings of 390 W/m2 and 265 W/m2 for clear skies, which are assumed to be one-third of the surface.
3. Therefore, emissions to space from clouds (two-thirds of the surface) ≈ 226 W/m2 to get the overall 239 W/m2 average (3 x 239 ≈ 265 + 226 + 226).
4. Clouds are high up and cold. Let's say 6 km up, where it's 249 K. If clouds were perfect blackbodies (100% emissivity) they would be emitting 217 W/m2 (248^4/10^8 x 5.67), so more gets to space than they actually emit. Nobody's sure what their overall average emissivity is, let's call it 75% (middle of various estimates of ranges). So actually, they are emitting 163 W/m2, and a lot more gets to space that they actually emit.
OK, this does not make sense any more, but that's what happens when you follow their logic. If the TOA effect is to block one-third of emitted radiation (265 ÷ 390 = 2/3) and net emissions to space from clouds ≈ 226 W/m2, then clouds themselves would have to be emitting 339 W/m2 (339 x 2/3 = 226). Assuming clouds were perfect black bodies (which they aren't), this implies a cloud temperature of 278K (5C), which in turn implies an average altitude of less than 1 km above the surface. So to make their logic and maths stand up, you have to make totally implausible real world assumptions.
5. So sure, there is 125 W/m2 'missing' with clear skies (390 minus 265). But for cloudy areas, there is 63 W/m2 more going to space than clouds actually emit in the first place (226 minus 163), and there is twice as much cloud as clear sky. How do they explain the 'extra' radiation? They don't of course, because that would give the game away*.
6. Now go back and read the bits in bold!
* The actual maths is much simpler. The surface not covered by clouds emits 390 W/m2 and that goes to space. The clouds, temp. approx 250K with 75% emissivity emit 165 W/m2, and that goes to space. Clouds cover two-thirds of the surface and so the weighted average emissions to space ≈ 240 W/m2. There is nothing obviously missing or being blocked.
Alternatively, the reason for the apparent discrepancy can be explained as follows: the atmosphere is warmer at sea level than at the tropopause because of the gravito-thermal effect. All warm atoms and molecules emit radiation, be they N2, O2, land, ocean, water vapour, water droplets, CO2, whatever. So there is more being emitted at sea level than from higher up. If you measure from space, you are (indirectly) just measuring the temperature higher up and not the temperature at ground level/cloud level.
Or maybe you are measuring some mix of the temperature at low and high altitudes - if you light a camp fire in the Arctic at night and measure it from a distance with an IR thermometer, you get a lower reading than if you light a campfire in the Sahara desert by day and measure it from the same distance.
Simples!
Posted by Mark Wadsworth at 16:47 0 comments
Labels: global warming, Science