Theia revisited - Climate check (WIP)

[Charerg]

There is a blue climate in the north around the tundra, I don't recognize the colour. Is it Dw something?

I think it's Dwb.

It is the right order but missing transition climates. The more plausible transition should be : Cfa, Cfb, Dfb, Dfc, tundra
Maybe this script is outdated?

The script should be up to date (it's the latest of my 6-step scripts uploaded in the main thread of the tutorial), in this case the source maps are probably somewhat off (especially since I modified them, ramping up the temps to account for the missing category in the originals).

There are places where C climates are surrounded by lowland D climates despite being at higher altitude and normally colder.
Other places where hot climates are surrounded by much colder climates but I assume these are mistakes or forgotten areas.

The January temp map has the western coast colder than the interior (which is inaccurate, you're correct that the coast should have milder temperatures), hence the C climates turn up in weird places in the interior (keeping in mind I ramped up most temps to one category warmer to account for the "warm" category that was missing in the originals).

@nwisth
Btw, in summer the coast should be milder and the interior hotter. Right now you have the hottest temperatures basically along the coastline, which is inaccurate since the sea is a very strong moderating influence.

Edit:
And about generating the temperature maps, yes, a grayscale base layer with an elevation adjustment layer on top works (and using a gradient to convert the grayscale into the desired discrete temp categories), assuming you're familiar enough with your image modifying software to use those features.

Alternatively just manually painting the temp categories works too. However, both methods require a degree of understanding about the basics of how temperature is affected by the various factors like oceanic currents and continentality. Taking a good look at the sample maps of Earth helps (see this post for the 1970-2000 temp maps, for example).

Edit2:
A slight aside about the ice sheets: note that ice itself reflects ~90% of sunlight hitting it back to space (it has a high albedo), so vast glaciers would have an immense effect on the climate all year round. It's also worth noting that the size of glaciers does not notably change on an annual basis: vast glaciers take millenia to form, and a long time to melt as well. Even with the present global warming going on, it is estimated the 2-3 km thick glacial cover of Greenland could take a thousand years or more to melt entirely.