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etymology

I thought the name came from INcoming SOLar radiATION; can someone check and add that if it is true? -Rotiro

—The preceding unsigned comment was added by 24.69.197.108 (talk) 03:33, 14 December 2006 (UTC).

Earth's Insolation

The whole section labeled Earth's insolation is improperly called that, as the section is referring to irradiance. this was mentioned earlier and will be modified. perhaps an article can be made for solar irradiance and this section can be moved there, as the figures are correct for the irradiance. Kopasa 14:00, 20 June 2007 (UTC)

I disagree that the figures are correct, I've read various different quotation of the value.
A little accuracy wouldn't hurt:
R= 6.96e8 Km (Sun's radius)
T= 5780 °K (Sun's photosphere or Effective temperature)
a= 5.6704e-8 (Stefan-Boltzmann Constant)
d= 149597876600 meters (Earth's average distance, Mariner 10), 1 AU
f= flux or Insolation.
L= 4pi·RaT = 4pi·df
Therefore, f=(RaT) / d
Then ((6.96e8 Km) (5.6704e-8) (5780°K)) / (149597876600) = 1369.912 W/m
This is the average. If you factor in the Earths's eccentricity, then the range is 1325.278 W/m to 1416.839 W/m

GabrielVelasquez (talk) 05:25, 28 December 2007 (UTC)

I'm not sure which figures' accuracy you are questioning. It seems you have made remarkably good predictions that track the observed value within 0.3%. The measured average, found here, is 1366 W/m, with an annual range of 1321 to 1412. Considering the number of significant figures in R, this looks essentially like a perfect match. My congratulations. Hertz1888 (talk) 16:37, 28 December 2007 (UTC)

1366 Watts per meter squared. I have looked at this Solar Constant Satellite mesured value in many internet and text sources, and I have found "Satellite mesured" values of anywere from 1365 to 1372 for the so called average/constant, and I don't know why you are using this particular number instead of another and would like to see a reference for that specific figure, average, or so-called constant. And as a clarification, even with the Solar Radius value, you rounded up and I'm only off this quoted value by 0.2883%, and that's if you accept this quoted value. If I recalculate using more accurate figures, using ((695950000)^2*(0.000000056704)*(5778^4) )/(149597876600^2), then I get 1367.8204 W/m, which is only off by 0.1333% GabrielVelasquez (talk) 01:49, 1 January 2008 (UTC)

reverted

I just reverted several months of minor edits: the article has been quite garbled since mid-February when some particularly bad editing occurred. In particular, the lead sentence has been composed of the first half of one sentence and the second half of another, rendering it devoid of meaning. zowie 15:41, 30 May 2006 (UTC)

Dookie

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Insolation is solar energy incident on the earth's surface. A distinction should be made to clearly distinguish between the rate of insolation and the total insolation received in a given time period. The rate of insolation is energy received per unit time per unit area; expressed in watts per square meter. The total energy received by a unit area in a given time would be expressed in, perhaps, megajoules per square meter in a day; as the Australian map shows or kilowatthours per square meter per year; as the world map shows. The distinction is between power and energy. The word "insolation" is sometimes used to mean either. When it is used the distinction should be made clear.

alexselkirk1704@hotmail.com

I disagree with "The word "insolation" is sometimes used to mean either." irradiance is the word for power over area (watts or Kilowatts per square meter) and insolation is the word for energy over area (watt-hours or Kilowatt-hours per square meter). Kgrr 10:35, 19 March 2007 (UTC)

It seems in accurate to suggest that the inoslation at 1AU is equal to that at the surface of the Earth. This would completely discount atmospheric effect.

The amount of energy striking the edge of the atmosphere (1AU) is called the Solar constant. Insolation is solar radiation striking Earth or another planet. Kgrr 10:35, 19 March 2007 (UTC)

units

The article states that units for insolation are energy per unit area (W.hr/m2), but the text accompanying the graphics to the right of the article gives units of power per unit area (W/m2).

Visible light?

How much of the 1366 watts is visible light? Infrared? UV? And how does the 1000 watts at the surface split up? And, it would be good to add a graph of power vs freq spectrum... -69.87.199.151 20:43, 7 May 2007 (UTC)

See Solar radiation Solar irradiance spectrum above atmosphere and at surface -69.87.199.249 13:04, 10 May 2007 (UTC)

Sunburn maximum?

There are some interesting suntan/sunburn practical questions, and it is not clear where to look for answers. If you lie down, clearly the greatest UV etc will be at high noon (local sun time). (Because the light intensity is maximum, and it also hits the body most directly.) But if you are standing up, walking around etc, and wearing a hat, things get very complex. The sunlight itself is more intense at noon, but the exposed skin surfaces are not pointed at the sun so directly. So, perhaps in some situations the sun exposure at high noon would actually be less than some time before or after, when the sun angles in to hit the face and body more directly?-69.87.199.249 13:12, 10 May 2007 (UTC)