Maximum light intensity underwater during seasons?

[Alfreds9]

Hi,

I was thinking if maximum light intensity underwater during seasons changes somehow.

I firstly thought about considering monthly solar irradiance (http://neo.sci.gsfc.nasa.gov/view.php?datasetId=CERES_INSOL_M) however I thought this would have been biased at certain latitudes due to seasonal variation of total light hours.

So, not considering algal growth affecting water tubidity and always considering sun being straight above water, do you think that you'd get a stronger (visible, not considering IR or UV) illumination during summer rather than during winter or would they reach 10, 20 or more meters relatively unaffected in either season?

Thank you

Allison

 

[nasu]

If the Sun were straight above the water (on the local vertical) the things would be different.
However, unless you live very close to Equator, the Sun will never be in this situation. And the maximum height in the sky varies during the year. I don't see why would you expect to have a constant illumination of the water when we don't get it for the rest of the landscape. In winter everything gets less light and heat from the Sun in the temperate and Nordic regions.
But maybe I misunderstood you question?

 

[A.T.]

and always considering sun being straight above water, do you think that you'd get a stronger (visible, not considering IR or UV) illumination during summer rather than during winter

If the sun is straight above water, you don't have summer and winter.

 

[Alfreds9]

If the Sun were straight above the water (on the local vertical) the things would be different.
However, unless you live very close to Equator, the Sun will never be in this situation. And the maximum height in the sky varies during the year. I don't see why would you expect to have a constant illumination of the water when we don't get it for the rest of the landscape. In winter everything gets less light and heat from the Sun in the temperate and Nordic regions.
But maybe I misunderstood you question?

If the sun is straight above water, you don't have summer and winter.

I see, didn't think about this, thank you very much...I always thought that zenith was zenith and it didn't vary noticeably, with temperature variations being mostly dependant on light hours and longer peak time.

Where can I find peak average solar irradiation by month (meaning the average maximum irradiation of visible light reaching a certain latitude at peak time during a month)?
I can only find total solar irradiation data on NOAA, but since they're a sum of irradiation values and obviously light hours, their total amount is somewhat biased and can't show me when average solar irradiation during peak time is higher during the year.
One could guess that it's higher when its hotter but again I don't know if I can be sure of this since it may just be a variation of infrared irradiation rather than visible light.

Thanks again.

 

[sophiecentaur]

If the sun is straight above water, you don't have summer and winter.

Or even day and night!