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by cousin_it 489 days ago
The color of a lake in satellite view depends on the satellite's viewing angle (which depends on the satellite's trajectory and the lake's location), the angle of the sun (which depends on the same things plus the time and date the image was taken), the weather, the satellite's sensors (false color is a thing), and how the images are processed before publishing. Overall I think it's almost impossible to estimate the "true" color of a lake from public satellite images, even if you used all pixels instead of just one.
2 comments

Also, I think most usually the lake names come from the color they have when see from the ground, rather than from above.

For example, a lake might be blue when viewed from space, but the locals can still call it a "Black Lake" because it's surrounded by mountains made of dark rocks, and when you stand at its shore you can typically see them reflected in its surface, giving an overall impression of a black color.

Yeah I stopped taking this post seriously when I read this sentence:

> I fetched the satellite image tile for the zoomed-in region of each lake center and read a single pixel at the center of the tile, which should give us an idea of the lake’s color

Well, I mean, it's an idea.
It’s a model, it might not be perfect, but you also need to decide how much scientific rigor and effort you want to invest in this problem.

To be honest, just picking a random pixel would have been fine, too, anything else is an overkill.