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I wonder whether the amount of UVA radiations one receives depends on the latitude one is located, and if so, to what extent? I looked at UV indices of different cities, but those are useless since they mostly take into account UVB, which unlike UVA depends on the weather condition (e.g., the presence of clouds will decrease UVB radiations but not UVA radiations {1}).


References:

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Yes according to https://www.biointeractive.org/sites/default/files/skincolorselection-educator-act.pdf (mirror):

How do you explain the relationship between the UV Index and latitude? (In other words, why does UV intensity change with latitude?)

The answer has to do with the angle of Earth relative to the sun. Latitudes at the equator receive direct sunlight year-round. Latitudes toward the poles receive sunlight at an oblique angle, which means that the same amount of radiation is spread out over a larger area than at the equator.


Now let's try to find to what extent the amount of UVA radiations one receives depend on the latitude one is located:

The 1995 study {1} looked at measured UVA in 4 cities in Chile with different latitudes (but some of them have different altitude, so this biases the comparison).

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As a reminder: UVA (315-400 nm); UVB (280-315 nm); UVC (100-280 nm). So only the table mentions UVA (the histogram only mentions UVB).

I'd definitely be interested in more thorough studies.


References:

  • {1} Cabrera, Sergio, Salvador Bozzo, and Humberto Fuenzalida. "Variations in UV radiation in Chile." Journal of Photochemistry and Photobiology B: Biology 28, no. 2 (1995): 137-142. https://doi.org/10.1016/1011-1344(94)07103-U
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