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The Causes of Temperature (Geophysics)
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Mick Harper
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In: London
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Anyone care to explain to me why it's hotter at the Equator than at the North Pole?
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Keimpe


In: Leeuwarden, Frisia
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Generally speaking, the average temperature goes down as you move away from the tropics, because the lower the height of the Sun in the sky so the same amount of sunlight is divided over ever more land.

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Mick Harper
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Thanks, Keimps, I'll take my deckchair up to the Arctic Circle, adjust it to the correct angle and that way the Sun's rays will be falling on me exactly as per the Equator. Thanks to you I won't need to take any woollies along. If I don't come back....

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Martin



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also the amount of 'atmosphere' the insolation passes through increases as you move away from the equator.
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Mick Harper
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'Fraid not, Martin, or at any rate not relevantly. The amount of atmosphere scarcely changes from the Equator all the way up to (roughly) the Arctic Circle, when the amount of atmosphere increases with a whoosh. (Somebody might post a diagram which demonstrates this since its hard to visualise.) Temperatures, by contrast, decrease rather uniformly Equator-to-Pole.
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Martin



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I am not talking about the amount. At the equator the sun's rays pass through the atmosphere perpendicular to the surface. At the poles they pass through at an angle. Therefore they pass through 'more' atmosphere before they reach the surface. On the way increasing reflection, scattering, absorbtion and that sort of thing.

Also the surfaces are generally white and so reflect sunlight away from the ground.

These two factors coupled with the earlier point regarding surface area explain why the poles are cold.
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Mick Harper
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I understand your point entirely, Martin, it is after all (half of) the orthodox explanation. And, like orthodoxy, you take the two extremes to make your point -- which is true, and which I freely concede. However it simply is not true for the points in between. The rays of the Sun pass virtually perpendicularly at all points from the Equator until about the latitude of the Arctic Circle. Yes, it is true there is a teensy drop-off with increasing latitude but this does not correspond with the large drop-off in temperature. Nor for that matter does temperature drop off 'with a whoosh' between the Arctic Circle and the Pole even though the angle of sunrays through the atmosphere drops off very suddenly indeed from about seventy degrees (from memory) to, as you say, nil.

Also the surfaces are generally white and so reflect sunlight away from the ground.
These two factors coupled with the earlier point regarding surface area explain why the poles are cold
.

You're doing it again. Taking just the Poles and the Equator. You are perfectly well aware that there is no difference in temperature between bits of the earth just inside the 'ice-line' from those just outside it. So albedo doesn't seem to explain the gradual difference in temperature with increasing latitude and nor does atmospheric thickness. And nor have you explained away the armchair effect. So joining all three together won't do it either.

To make an Applied Epistemological point. You can reasonably suspect that orthodoxy is making a paradigm error when it starts coming up with too many reasons. One should do it.
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L R B Quirke


In: Auckland, New Zealand
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The 'armchair effect' is vitiated by the fact that we are dealing with ambient temperature. It makes not a scrap of difference to the overall temperature just because your particular three square feet is getting the rays full on when everywhere else in your neck of the woods isn't.
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Mick Harper
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Right-o, Quirkey, I'll build a nice mountain range along the Arctic Circle making sure they are the correct gradient for mimicking the Equator. Will I be able to grow tropical fruits on their southern slopes? No, I didn't think so either.
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Brian Ambrose



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Some other points to consider, Mick..

1. Don't mix up visible light, and heat. Heat is infra-red radiation (lower frequency). You can have loads of light but no heat.
2. It's possible that some infra-red is reflected by the atmosphere, this would be more pronounced as the angle becomes more acute.
3. Equatorial regions get more sun due to less cloud cover. There is probably positive feedback going on.
4. You know from experience that the sun directly overhead is much hotter than when lower in the sky.
5. These effects seem to be large in comparison with the modest tilt of the Earth. You can poo-poo the apparently large effect of the Earth's tilt, but it seems to be a fact that winters are colder than summers.
6. The equator is, in a real sense, closer to the sun. Before you poo poo this, see 5.

Warning: Some or all of this may be bollocks.
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Ray



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Actually, Mick, when you think about it it stands to reason that the relative thickness of the atmosphere is at least partly responsible. If you ever star-gaze you'll find that those nearest the horizon are the least clear. The thicker the atmosphere the more fuzzy and shimmery they become. For the same reason the sun has far less brightness at dusk and dawn.

Now as I understand it, heat and light are the same thing, but on different parts of the spectrum. It must be so as we receive the sun's light and heat simultaneously. We don't have to wait for the light to appear after feeling its warmth - or vice versa.

So there you have it: the atmosphere absorbs the sun's heat and light.

One of your points, Bri, is bollocks. There is more cloud cover at the equator than anywhere else on earth!
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Mick Harper
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Look, I am perfectly happy to accept all this thickness of atmosphere and perpendicularity-to-the-surface stuff, but there's an Applied Epistemological aspect to all this. Consider the situation on 21st June in a) Lagos and b) London. Now it is perfectly true that at midday the sun beats down on Lagos more than London, and this is the case that orthodoxy always uses to make its case. However, it's not always twelve o'clock. Let's move the clock on a few hours, in fact let's note the situation for all day on 21st June

12 noon till 3 pm: marginally Lagos (sun overhead)
3pm till 7pm: marginally London (sun higher in the sky)
7pm till 10pm: completely London (sun has set in Lagos)
10 pm till 3 am: equal (no sun either place)
3 am till 7am completely London (sun hasn't risen yet in Lagos)
5 am till 9 am: marginally London (sun higher in the sky)
9 am till 12 noon: marginally Lagos (sun overhead)

In other words, it's overall in London's favour because
six hours marginally Lagos
six hours marginally London
eight hours completely London
four hours the same for both

Now I accept that it is perfectly proper to argue that Lagos's advantage around midday is so intense that it will outweigh all the other times of day, but the AE point is that orthodoxy never does the sums and actually proves it. And since this supposition happens to underpin a whole raft of meteorology (ie it's an academic paradigm theory) then the failure to do the sums is a clear case of "careful ignoral".

And please don't write in and say "'Course they done the sums, stands to reason" unless you can actually find some place where they have done the sums. And even then you'd have to convince me that every geographer teacher teaching this theory as rote has been made aware of these sums before teaching it "as a fact".
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Martin



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orthodoxy never does the sums and actually proves it

What sums? What would be these sums be measuring exactly?
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Wireloop


In: Detroit
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Maybe the centrifugal force of the rotation of the earth is 'forcing' all of the 'cold' away from the equator towards the poles. What do the weather patterns tell us?
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Mick Harper
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What sums? What would be these sums be measuring exactly?

Applied Epistemology is a system for holding orthodoxy to account. The reason this is necessary is that orthodoxy does not (normally) have a system to hold itself to account -- nobody voluntarily holds themselves to account and orthodoxy (virtually by definition) is a monopoly, usually de facto sometimes de jure.

Now, take geography. Every geography department in the world is at the top of its own tree. There is no Department of Paradigm Checking at either the the university level, the national level or the international level. The only "check" is peer review ie every tree checks every other tree but never the forest. And of course every geography teacher has to have passed through a Geography Department and been certified as being sound in all current geography paradigms. This is a recipe for the indefinite survival of all current paradigms. Whether they are true or false.

You have perfectly illustrated what goes wrong in such an environment. Not only does nobody ever do the sums, the very idea of doing the sums brings forth only bafflement at why anyone would wish to do so. Have a look at my figures for Lagos and London, Martin. Do you agree they are correct (give or take)? If they are, and I doubt that anyone could seriously disagree with them, then there would seem to be a case to answer. Given that most of meteorology is based on the supposition that Lagos is hotter than London because a) the sun shines overhead more and b) it passes through less atmosphere and yet c) this isn't necessarily true for London vis a vis Lagos, then somebody, somewhere ought to "do the sums".

It seems a pitifully small thing to ask and yet over and over again you will find that academic subjects will devote millions of man-hours to not very important things and nil man hours to checking very important ones. We Applied Epistemologists call this behaviour "Careful Ignoral".
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