The Köppen–Geiger climate classification made simpler (I hope so)

[Charerg]

I have attached the files I was talking about earlier if you want to have a look.
It's strange that Psd files become much smaller if you turn the layers off.

Chareng.zip


I have to say that I'm impressed by the compression ratio. Normally it's in the range of 5%, here it's around 75%.


Also, Unless I missed something, you added more precipitation categories but haven't explained the difference this creates when placing them.
I'm not sure that the cutting halfway technique give very good results. The progression from one category to the other is not clear, even in my tutorial.
I find it not too difficulty to know where it rain and where it does not, the extremes. Yet everything in between is unclear.

The problem comes from using odd numbered categories. The categories are not bad per see but they are not helpful to understand the precipitation spread.
We should do another map for reference using 5 or 10 ml categories. It will be easier to see the progression.

That is a very good idea. Actually I kind of think both your original (extremely detailed, certainly more so than my calculations which used purely averages) and my precipitation threshold calculations are to some extent meaningless because the precipitation categories we use are so broad. For example, one temp combo has a threshold of 800 mm and another has 700 mm, and they both have the same precipitation pattern. Does the difference matter if the annual precipitation could be anything between 500 to 1000 within that same precipitation pattern?

This is actually a big reason why I decided to merge many of the temperature combos (within the same climate class) in the scripted version for GIMP (besides making it faster to write and easier to modify): I felt there wasn't any advantage to treating them separately as opposed to lumping them together and just using an approximate average threshold to determine whether it's an arid climate or not.

As to placing the precipitation categories, I admit that I don't have a really great way to place them myself. What I personally do is a combination of guesswork and looking at the example maps of Earth's precipitations for reference. As well as taking into account the general precipitation patterns covered in your instructions. At the end of the day it's an approximation, if only because we're working with precipitation data from only two months. Although I'd say that using more precipitation categories does have one distinct advantage: the sheer volume of combinations gives you more room to create a transitional BS stage between BW climates and more humid ones.

But making an example precipitation map using linear intervals for reference is indeed a great idea. And should be easy to generate too with a gradient map. I'll try to post some during the weekend.