This is where I will be in the tropics next week. The sun is below the horizon for 12 hours a day.
This is the North Pole in summer. The sun stays at the same elevation all day.
Is the sun higher in the sky in the tropics for most of the 24 hour period, or at the pole?
Guess we are going to be talking about the importance of the angle of incidence now…
Suppose, for simplicity, the area of incidence is water or ice or rock. Again for simplicity, suppose that water or ice or rock is made from molecules.
From where do molecules get the knowledge on how to change temperature according to angle of incidence? Apparently they always go to the next library and study academic “text” books, eg. climastrology.
http://www.vurivaexpeditions.com/wp-content/uploads/2012/09/Vuriva-Safaris-Kilimanjaro-National-Park-Mountain.jpg?1415232000031
“This is where I will be in the tropics next week.”
And the Dogs ?
At both poles , in midsummer it goes round and round like a control line model aeroplane in a nearly flat plane, but never about 30 degrees above the horizon. Not exactly “high in the sky”. .
That doesn’t have any impact on this discussion.
I beg to differ, it is precisely to the point!
Deda stop being obtuse.
Tony made the simple and correct statement that during the height of summer, the poles receive more sunlight across a full 24hr day than do the tropics. See the chart posted by Gail above.
Tonys claim is that despite this extra sunshine, the poles do not reach high temps largely because of the lack of ghgs, namely H2O.
What Tony omits is the intensity of the sunshine. Intensity matters in the real world as the following example will demonstrate.
Place a hot water bottle at 50degC against your belly. The bottle emits about 600Wm2. Even after 24 hours, your belly will not burn.
Now drop a drop of boiling water on your belly. This drop emits about 1100Wm2 and will scold you instantly. But your belly received lots more “sunshine” from the water bottle yet didn’t scold you.
To conclude, having a 24hr day with the sun never above 23.5 deg will have profoundly different effects on the surface than the shorter and more intense daylight at the tropics.
My beef with Tonys claim is that correlation (lack of ghgs = cooler poles) does not equal causation.
To be convinced, I’d need to see evidence that shows it was the lack of ghgs that caused the cold as opposed to the cold causing the lack of ghgs.
Baa … good clarity as always.
Arithmetic: since at the tropics it has 12 hours the horizon so the north pole is guaranteed to have the sun higher in the sky than the tropics for more hours per day, namely 12+time to match the pole’s angle (from sunrise) + time from match to sunset.
12 hours “below the horizon”
Oh come on, please ask a better question, is earth center of solar system does not count in this day and age, NYTs, Gaurdian, MSNBC or religion as source does not count.
How about what are the coldest and hottest months on average during the year on earth?
Perihelion, aphelion, eccentricity, and albedo, could be Greek.
Quick idiot guess on what latitude where you live, theory, or check data?
I think this another trick question. No matter where on the Earth’s surface we all get an average of 12 hours er day of sunshine – actually a little more because of refraction. The Sun has actually set when it is about 30′ of arc above the Horizon.
That should be set and risen when it is seen to be about 30′ above the Horizon.
ah one day it will become warm again in the Arctic region where crocodiles used to swim. I guess it’s the tilt of the planet that allowed this.
continental drift
after all it will be the tilt of the planet that will allow monsoons to return to the sahara desert in some tens of thousands of years and no more cold nights there!!
interesting to note –
“Strange as it may seem 8000 years ago when the cave paintings in Wadi Sora were made the Sahara was getting more sunlight than it is now. And that extra heat helped bring the monsoon rains to this desert. But how did the Sahara get more solar energy.
Back when the Sahara was green, the tilt was close to its largest possible angle, 24.2 degrees. Which meant that 8000 years ago the Sun shone more directly, more intensely over the Northern hemisphere”
Folks this is all just straight maths.
The tropics receive 12 hrs of sunshine at the average angle of 45Deg. A total of 45 x 12 = 540 hr degrees.
The N Pole receives 24 hrs of sunshine at the angle of 23.5 deg. A total of 24 x 23.5 = 564 hr degrees. (summer solstice)
This of course doesn’t last long. As soon as the sun drops to below 22.5 degrees, the pole no longer receives more sun than the tropics.
All the above under clear sky conditions.
Intensity cannot be dissmissed.
The average angle in the tropics at the solstice is actually much lower than 45 degrees. For almost 12 hours a day it is zero, and is only above 45 degrees for about six hours or so.
That’s why I multiplied by 12 and not 24.
In a 12hr day, the sun travels from 0 deg to 90 deg back to 0 deg which is an average of 45 deg. Across a full day this halves to an average of 22.5 deg.
At the pole on the day of summer solstice the sun stays at 23.5 deg for 24 hrs.
Unless you can show why my numbers are wrong I’ll stick to them.
The Sun is much more intence in the winter than in the summer here in Florida. We just have to deal with the weather coming from the north.
It’s the angle too. The Sun is more overhead and closer in tropics than over the poles. More directly overhead sun rays penetrate the atmosphere, while angled rays bounce off more.
Atmosphere thicker in tropics than @ the poles.
Having lived in Fairbanks and Panama – I know what it feels like.
Hmmm, interesting. Hawaii on the other hand has almost the same length of day all year round. It varies only a little, and most certainly does not stay “below the horizon” for 12 hrs a day.
Really? What angle above the horizon does the sun have at night there? And roughly how many hours long does the night happen to be?
Why are you talking about night? … If you can read, I said “DAY“
You are playing with the term ‘Day’. For you it is only time when sun is up and not either a solar day or sidereal day or something close to 24 hours. You still didn’t answer what angle the sun has over the horizon there at night. And you haven’t answered how many hours of night there are there during a 24 hour period.
Sun is ALWAYS HIGHER in the tropics. Pole NEVER POINTS directly toward the Sun. Elementary, my friend, elementary…
At night, the sun is higher in the tropics? You are a real genius.
Pardon, I was under impression we are talking about daylight, let me make a correction. The sun is higher in the tropics of Cancer at least 11 hours out of 24. I would recomend a summer trip to let say, Resolute Bay, so you would know what I am talking about…
They have daylight at the pole for 24 hours a day at midsummer. What part of that simple fact are you incapable of understanding?
Please take a step back and stop being an idiot.
What is the definition of tropics? Tropics include all ALL areas on the Earth where sun reaches subsolar poin, point directly overhead at least once during the solar year. (Wikipedia). So anynywhere ABOVE Tropic of Cancer, the Sun is LOWER!!!!
“The sun stays at the same elevation all day.” This is simply not true. Sun is higher at noon, than at midnight.
At the pole, the sun stays at the same elevation all day. You are a real genius.
I do have to disapoint you, I am not a genius, just been there. the Earth remains tilted all year.
I am going to start banning idiots soon. I don’t have time for this.
Let me correct myself. You are right 1 day, I remaining 364.25. ;0)
Please stop the stupidity. The sun behaves the same way every day at the pole. It makes a slow spiral down for six months, and then a slow spiral up for six months.
If there is more than a trivial change in elevation of the sun during a 24 hour period, then I would argue you are NOT at the pole. Perhaps you are playing games with ‘Day’ as squid likes to and are not considering it a roughly 24 hour period.
It is a pitty that you consider somebody with real experience in the arctic an idiot, simply because he disagrees with your theory. How Climatologic….
If you had been to the North Pole, you would know that what I am saying is correct.
Nope
I have been above the Arctic Circle and the sun goes up and down each day. It just does not go below the horizon. At the North Pole the Sun may be up all day, but at its low angle the energy density is quite low, between 17 and 3%. As the North Pole is simply the center of the Arctic, the average Arctic region sees the Sun rise and fall, vastly decreasing the energy input. At the low angle, the energy per sq meter is about 17% of direct vertical sunlight and, as the sunlight also travels through a much longer route through the atmosphere, it is diminished by about 17% also. So, the average is about 3% of the energy input. Still quite light enough to be bright but only because of the high albedo.
“It makes a slow spiral down for six months, and then a slow spiral up for six months.” It may be slow in tropic, but is actually quite significant at poles. Before you start calling people idiots, read it twice, think about it. It is not that hard.
I’m going to ban you very soon.
I am just wandering how poor Amundsen navigated to the North pole. Compass was useless, Sun at the same height above the horizon….
The only time Amundsen went to the North Pole was flying over in balloon. I’m almost out of patience.
Hm that is a news to me, you wouldn’t be cofusing Amundsen with Umberto Nobile’s Italia dirigible by the chance?
Amudsen was with Nobile.
How did he navigate in the “baloon”?
It doesn’t go by how many hours. It goes by total W/m2 during the whole 24 hours. Mid-day sun in the tropics easily blow the poles away and their miserable 67 degree zenith angle.
Which is peak at the poles on the solstice
https://stevengoddard.files.wordpress.com/2014/11/screenhunter_4712-nov-17-22-30.gif?w=640
There’s way too much imprecision in this discussion–from all sides.
I used the solar calculator at http://www.esrl.noaa.gov/gmd/grad/solcalc/ to record the sun’s elevation throughout the day. I chose Jun 21, 2014, the summer solstice and recorded the sun’s elevation hourly for three locations: the North Pole, Anchorage Alaska, and a point on the equator.
At the north pole, the sun’s elevation is about 23.5 degrees all day. The sun at Anchorage reaches an elevation of about 52 degrees. The sun at the equator reaches an elevation of 66.6 degrees.
Solar insolation is proportional to the cos(90-elevation angle) for angles above the horizon. Integrating over the 24 hours, I get the following: the north pole sees 9.5 hours direct sun equivalent, Anchorage sees 8.7 hours, and the equator 7.0 hours.
So Steve/Tony is right: at the summer solstice, the Arctic gets more solar insolation than the tropics.
However, this statement is misleading in many ways. I’ve neglected the effect of the lower sun’s rays at the pole being absorbed more by the atmosphere than at the equator. The peak solar elevation is much higher at the equator than the pole.
Furthermore, the summer solstice is the most favorable day of the year for the north pole. That’s the day it gets most solar insolation and the day the equator gets least (though the equator doesn’t vary much). (BTW, the south pole gets no insolation that day.)
Finally, a day’s solar insolation affects that location’s change in temperature far more than it affects it’s absolute temperature. The tropics are warm all year around, but the pole is very cold coming out of winter.
Blaming the cold weather at the poles on the lack of greenhouse gases is wrong. (BTW, the standard assumption is that CO2 is distributed uniformly.) The poles are cold because they get less sunlight over the year.
Water is immensely important to the planet’s temperature distribution. The oceans transfer heat from the tropics poleward, clouds and thunderstorms cool the tropics, and clouds help retain heat at night. The atmosphere also contributes with convection and winds. It’s complicated and oversimplifying is misleading at best.
Worked offshore Nigeria 12 hours of night 12 of day sun came up every day in the same place and fell back to the sea in the same place winter spring summer and fall , Now working up North In Canada different story dark all winter sunny all summer travel a bit people ;>)
Solar insolation chart:
http://www.roebuckclasses.com/maps/physicmap/earthsun/insolationchart.GIF
Looking at Gail Combs graph, The Equator has the greatest area under the line, the Pole has the greatest peak and the least area under the line.
The question: “Is the sun higher in the sky in the tropics for most of the 24 hour period, or at the pole?” Which 24 hour period? A specific day, an average day, any day, all days.? If the day is around 21 June North or 21 December south, the pole wins For most other days, given the choice of 2, the tropics wins.
Any clarification on what you are really asking?
No, the sun does not stay at the same angle all day in the Arctic summer. It appears that someone has not been to the Land of the Midnight Sun. I have. The sun rises to the low angle in the picture above and then it drops in the evening, it just does not gobble the horizon during the summer, such that one can still read a newspaper by the dim light, being always a bit above the horizon. It is false to claim that the sun is at the angle shown all day, just wrong!
At the North pole, it stays at the same elevation all day. I am completely fed up with stupid, aggressive comments
No Higley, if you woke up at 6am at the Noth Pole on June 21, the sun would be at 23.5 deg. At noon, at 3pm, at midnight and at 3am the sun would still be at 23.5deg (drifting each day by a small fraction)
Try to visualize the following…
Tip the still spinning globe 90deg so that the pole is facing the sun. Wouldn’t the sun be permanently directly above 24/7?
Now work back to 23.5 deg