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Comment by davidw | Hacker News Reader

I'm not your target market, so don't worry too much what I think, but when I zoom in on Oregon, I don't get a good sense for the sharp contrast in rainfall across the state.

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What view were you looking at? I was able to find this page: https://xrain.info/data/4878573/seasonal. Oddly, the selection box does seem to indicate I don't live in Portland, which the annexation ten years back would be furious about :)

I was just looking at the map.

You are seeing the rain shadow effect if you are wondering why there seems to be higher rainfall in western Oregon compared to eastern Oregon. [0]

[0]https://en.wikipedia.org/wiki/Rain_shadow

My point is that his map doesn't do a good job of showing that, when rainfall differences are pretty dramatic. Something like this shows it much more clearly:

https://www.eldoradoweather.com/climate/us-states/oregon-ave...

As well as regional differences like the Wallowas vs SE Oregon.

I agree that the effect is a lot more subtle because of the color scale employed. The absence of a legend also impairs interpretability.

Cam here to say the same thing, the map appears to be overly smoothed and does not capture the sharp rainfall changes that often occur due to the local topography - e.g. when going from the windward side of a mountain to the leeward side.

For example, according to the map the rainfall at world's wettest place Mawsynram, is about 4300mm, which is about 35% of the the actual. https://en.wikipedia.org/wiki/Mawsynram

I think parent is saying they DON'T see the rain shadow. I think it's perhaps a problem of opacity when you use the "mean annual depth" background layer. It's visible, but subtle.

I see what they are saying now. The use of the blue color bar tends to wash it out so it isn't as useful to "flood" the map view with blue water for this display as it would be if you changed to a color bar with other gradations that would allow the user to see at a glance that eastern Oregon is dry relative to coastal Oregon. A legend would also help.

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