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

[Azélor]

I did the climate for you world by myself to see if i was getting the same results, in case the tutorial could be improved. It took a long time even if I rushed it a bit, hopefully it will be worth it.I'm going to start with the temperature maps since there is less stuff to talk about.

*I have to warn you that I might make some small changes to the temperature section , more details about it later. Also, I change the explanations in the section on the effects of altitude and added a new picture but it's still the same thing as before.

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To set the table for the temperature maps, i did 2 influence maps.

The color mean:
Red; hot current
Green: mild current
blue: cold current
yellow: continental
no color normal
and continental plus is not there, the climate is not extreme enough

January



July

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January: Before reading this, i need to say that I'm 100% sure that i skipped some place regarding the temperature changes due to elevation. But most of it should be on the maps.

I did not notice it as first but there is a problem with the temperature at higher elevation. I don't know if you used the table I provided but you seemed to take inconsideration that the temperature scale was linear. It's actually pretty erratic. It's true that you need to lower the temperature of 1 category for each 1000m for the hottest one but other (especially the coldest) cover a wider range of temperatures. So, for example, the north eastern continent summits would be much milder. If the base temperature at sea level is yellow: it's between 0 and 10, or 5 degree on average to make it simpler. Since the elevation is brown, it's 4000m high. The time lapse (cooling of the temperature with a rising altitude) is somewhere between 6 and 9 for 1000m depending on humidity. I took 6,5 for simplicity. So, for each 1000m, you lower the temperature by 6,5 degree Celsius.

*You can have a look at the temperature progression based on a linear scale to see the difference. Some bars are bigger than others.

4km x 6,5 = 26 degrees
since the temperature was around 5 at the base: 5-26 = -21
which mean that the high central range it should be either turquoise (dark green if you prefer) if the base color was yellow or green if the base is warmer.

I made the image smaller but the originals were blurry. Anyway, your maps just need some tweaking. I assume that use haven't put everything on the same layer? (I might need to warn people about it)



I will cover the map point by point. A lot of places have slightly different temperature due to some randomness I suppose.

1- I used a mild oceanic influence, which explain that the coast is cooler. But I think your is more accurate. Also, I believe that the interior should be hotter at that latitude.
2- Same as above, the interior should be pretty hot.
3,5, and 6 : there is a maritime influence there and the temperatures should be more spread out.
4- I think it should be warmer. it's a hot current.
7- we could compare the climate of this coast with eastern Greenland and Svalbard. The current is kinda mild and it should be warmer than Antarctica. That is true for most of the polar coast except in the middle where it should be colder because of the ice and the small heat exchange from the warmer seas.
8- a bit warmer maybe. I used a hot current influence there.
9- mild influence and as above, the temperature tend to be more spread out. Think about Chile and Argentina.
10- The change of temperature due the the altitude is smaller.

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July:



1- it's winter and made it cooler because of the rather mild oceanic influence.
2- The orange stretch to much to the south. On the other hand, maybe your right and I've put too much dark orange in the small sea.
3- It is a very narrow band of land with a very strong maritime influence, I doupt it could be that hot, maybe in the valleys inland but not on the coast.
About this continent , and in general where the winds are blowing from west to east, you should move the maximum temperature a bit more to the east maybe. In my version, i considered that the mountains in the west somewhat blocked the winds which limited the air flow from the sea, hence higher temperatures.
4-The ocean is actually kinda cool and since winds are blowing from north to south east (approximately) it makes the climate milder, especially on the coast.
5- I'm not sure it should be that hot.
6- Personally, I made it milder, taking southern Asia as a reference.
7 and 8 - I expect the sea to be trapped under a layer of ice with really cold temperature. The winds are blowing from the pole toward the continent which push the cold air inland. Maybe I pushed a bit too far since the continent is also affected by the westerlies, which should bring milder air from the western ocean.

That's it for the temperature maps.

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Precipitations are a bit more tricky, partly because my system is a bit rigger ? (To make or construct something (in haste) or in a makeshift manner)

Anyway, maybe I can improve it.

Starting with the pressure maps:

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January, the pressure looks alright.



About the winds, there is a lot of guesses and most of them are not really changing the weather too much
1- I don't think it changes much but I think it's mostly under the westerlies, which means the wind have a tendency to flow to the east. If the did converge to the north, I don't think it change the precipitations much.
2- I actually have no idea
3- Exact direction of the winds seems irrelevant since it's dry
4- At first, when looking at the continent, I thought that it looked like North America, but it lacks a huge mountains range to separate the high pressure system in the west from the rest of the continent. Therefore, it makes the winds blow more from west to east. Winds coming from the south are deflected in a clockwise fashion.
5- I don't think this should have such a large impact on the winds.
6- I don't see a reason why the winds should blow toward the south.
7- More a general note than a specific one: from here, the winds tend to get deflected more toward the north by the high pressure systems of the interior of the continent. As it is the case in Russia during winter.

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July:



1- the air should converge but I'm not sure how exactly but again, i think the westerlies should stronger. Maybe there could be some easterly winds from the eastern ocean in the southern areas. My guess it that it should look a bit like the American summers. But from my point of view, it's the continent that I have the most uncertainties.
2- In most case, the bending direction of the arrow is not so important but the direction of the wind is.
3- On my map, I made the winds from the north converge and then flow to the east and eventually they would be deflected to the north probably.
4- This area reminds me a lot about the Indian subcontinent, same shape, same latitude. I made it a low pressure area.
5- I almost forgot about this area... Just like in Ecuador, the air converge under the ITCZ. Since the south is colder, the ITCZ tend to stay more on the northern side.
6- The direction of the winds here is just really confusing, I'm just going to ignore that area and do it roughly.

I think the rest was pretty good.

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I made the green and white maps, even if they are just temporary, they can help with the precipitation maps. Green is humid and white is dry.
Yea, I know, I'm more the visual type of person. I need the illustrations.

January



And July

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I will stop there for today.
There are about 39 points I wish to talk about just for the precipitations so it's might be another long post.
I would like if you could give some feedback, if something in the tutorial was poorly explained in light of the point I mentioned in the post. Of course, there are things that depend mostly on guesses so I could be wrong on a couple of things but it's not easy to know.

[Charerg]

Wow, that's a lot of work you've done! My thanks for putting in the effort!

I'll post a more detailed response once I've gone through your post in detail, but for now I should mention that I updated the Atmosphere & Winds maps from the previous versions before making the new precipitation maps.

Jan:


July:


I haven't read through your comments about my previous Wind maps yet, but I think these ones are a bit more "readable" (and should be a lot more accurate).

Edit1: Ok, went through your comments Re: Winds. I agree that the previous maps had quite a few inaccuracies (as you pointed out). Comparing your comments to my updated wind maps, I think I already managed to correct the previous inaccuracies, but do point out if I missed something.

Regarding the tutorial, I think it might be helpful to actually draw the ITCZ as part of the process of determining wind directions, since the winds tend to converge there. At least I found it useful. Secondly, it might be useful to draw a few tiers of pressure like I did in my new maps, since this can make it easier to visualize the effects the high pressure centers have on the winds. That said, this does complicate the tutorial, and I guess it depends on just how accurate the person going through the tutorial wants the results to be, so maybe it should be an "optional" step.

Edit2: Temp maps

I have to admit that my temps maps were pretty "rough" and I just ramped up the temperature one category for each 1km elevation or so regardless of latitude. In this case, it's more of a case of "not reading the instructions until the work is already finished" than a fault with the instructions themselves! With that in mind, your versions of the temp maps should be more accurate (generally speaking). It should be interesting to see how this will affect the climates.

Edit3:

The maps should be visible now.

[Azélor]

I can't see you files, they haven't uploaded. This tends to happen when you take too long to write the message, if you get disconnected.

But as I said in the other message the temperature at sea level should be good but not the ones at higher elevation. I can't guarantee that I haven't missed an altitude layer.

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Now for the precipitation maps

January: I did the precipitation for the orographic effect, but they were made roughly. From what I can see, they seems pretty similar to yours.
It is possible that I have confused the several maps while I was writing the numbers on them. I will specify it when I wrote the number for nothing.



5,6,11, never mid, it's pretty much the same. But 6 might have a lake effect like Northern Iran.

1 and 17 -One of the biggest mistake on the map. This area is supposed to be dry like the coast of South Africa because it's a cold current.
4- is exactly like South Africa (Cape Town)
3- (sorry if I don't follow the order of the numbers) Close to the Equator is the ITCZ. Reminds me a lot of Ecuador.
12- The landmass becomes hot since it's close to the tropic. It draws the air fro the sea toward the south. It's borderline between the ITCZ and the polar front.
2- That's the effect of the ITCZ. Mountains are not high enough to block all the precipitations since the water contain so much moisture and there ar e many wide valleys where the air flow is not interrupted. The remains dies out somewhere over the continent.
Also, the souther semi-closed sea is much more humid since it receives the winds from the ocean. Evaporation is the sea also help giving more precipitable water. But the precipitation don't go as far inland.
7 and 14: these are likely Mediterranean climates. It's supposed to be their rainy season. The winds are blowing more or less following the latitude lines. 14 is actually not so bad, the exact position of t he dry are is not the same in America and Europe for example.
8- With the westerlies blowing, the precipitation can go far inland.
10- I'm not sure about the precipitations on the east coast. I'm not sure if the area between 30 and 40 degree of latitude should be drier or wetter. Since the high pressure centerr in the west have a stronger impact of the winds, it might make more sense if the area was drier like in your version. I'm not sure.
9- They got the winds in their face, it should be more humid. Norway and Chile are not really good example since they got mountains blowing the flow of air.
15- the polar air is pretty dry. The continent on the center is protected by the mountain ranges in the north from some of the cold air.
16- I'm not sure the range is big enough to block all the moisture. It's definitely drier but not so much. But I could be wrong and maybe it's like northern Venezuela.
18- it's really dry in winter but polar ocean do bring some moisture during the summer.

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July:



5,6,7,10,15(India),18, 19 and 21 seems alright, never mind.

1 and 16- Same as mentioned for the other map. Mountains should be drier in that kind of area.
2- The ITZC, we could debate on where to actually put it, but it doesn't seems so bad either way.
3 and 13- like in Europe, the climate is dry til around it reaches the 40 degree.
4- The interior of the continent is hot and a low pressure system. It gets some dry air from the west but the moisture roam freely in the north due to the Westerlies and it also come from the south east like it does in North America.
11- I wasn't sure f it was supposed to be dry since it's close to a high pressure center.
8- Is affected by the polar front and should be more humid. But 9 is not.
20- Like in South Africa, the precipitation are limited to the coast here.
12, since the winds are blowing mostly from west to east, they carry more moisture. But it's still drier than on the south pole summer because it's colder and there is less water available for evaporation.
14- I made the precipitation follow the flow of the wind. In my model, he continent is smaller than Asia, meaning the westerlies are stronger at this latitude. Meaning is not as humid as the south.
17- Not sure

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I here are the precipitation layers in png

January



July

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Btw I edited the step 7 post to include manual instructions. But once you layers are improved, I don't mind running the script if you send them to me or put them here as PNG. PNG is a good format if your using plain colors (the opposite of pixilated textures) and you won't need to compress them.

[Charerg]

Ok, I finished updating the temp maps. They're essentially more or less copied from your versions, with a few minor differences here and there, and possibly a few corrections with a couple of mountain ranges. Nothing major, in any case. At this point, I think it would be ideal if you could run the climate script with both your version of the precipitations and mine (posted in *.png in post #105), since it would be nice to see what the results look like before I return to the precipitation maps (in any case, I think a slight break is in order before I revisit the precipitations).

Also, another reason why I'd like to see the results is that while I agree with a lot of your suggestions, like area 2 (in your january map), I'm a bit on the fence with a few areas, namely 1, 4, 12 and 17 (again, january map). With area 12, the large peninsula (called Akanrias) forming the southern portion of the large western continent (Eocidar) has a pretty mountainous coastline creating a rain shadow (even if the mountains are not that high for the most part), and I think the Westerlies are blowing too much "along the coast" to fully cover the interior. Hence, I think it should be (relatively) dry, probably something like Patagonia, at least in the interior. That said, I confess it's possible I overestimate the effect of the mountains, after all the Alps don't seem to create much of a rain shadow.

The climate patterns of Southern Eocidar are also complicated by a monsoon cycle, since the landmass in question is very large, and at least I postulated that the ITCZ would reach almost 30 S latitudes during Southern Summer, causing a strong monsoon affecting the coastal areas north of the 30 S latitude. The Western coast is also very mountainous, so there would certainly be a lot of orographic lift. All in all, I think the height of the mountains alone would likely prevent "extremely dry" climates along the coast, except a narrow strip of coastal desert. That said, it's possible I made the "rainy area" reach too far south, since the region is (as you mentioned) influenced by a cold current.

Although I don't think the said cold current would be as cold as the Humboldt current, since the really "Arctic" water would be deflected into the large channel between Eocidar and Nomune (the southernmost continent), most of the water flowing along the southwestern coast of Eocidar would be 30-50 latitude water. Also, the southern waters of the "Outer Ocean" (Agalhain) might not be as cold as the Pacific, since the "Antarctica" of this world is located north rather than south. Still, I might have made it too wet, it definitely shouldn't be wet enough for a rainforest climate, but I still think your version is too dry.

Re: area 17. Again, I think here the orographic lift should prevent dry climates, except in the "rain shadow" of the mountans and the very tip of the peninsula (called Menduine).

Anyway, it should be interesting to see what sort of climates turn up. The revised temp maps are in the attachments. Oh, and many thanks for putting a lot of effort into this, it's always a lot easier to see potential flaws when an alternate opinion is available!

EDIT: In case you haven't run the script yet, I did actually update the precipitation maps slightly. Some your suggestions are implemented in the new versions, namely southwestern Eocidar is drier (though not as dry as in your version), and a few other adjustments too. The new maps are in the attachments.

[Azélor]

While you might have a point in that the Drake passage is much narrower, yet it doesn't have a very large impact. The passage south of Africa is much wider and it result in a very similar climate for Namibia, vs Chile. Same thing for California and the Mediteranea. All these place have very similar climates.

If we compare them more in details, we see a small difference between the north and south hemisphere. The coldest currents do seems to have an effect of precipitations (or it could be something else) but it's not an huge difference.



That is pretty much what I followed but I don't think this model can be applied on the central eastern continent very well.
In the other areas, although we could play with the parameters, it would still be mostly dry.


I wasn't entirely sure how to treat 12, my guess was that it would draw moisture from the north AND the south, since it's pretty hot and close to the ITCZ.

17, Was a bit harsh I agree but it does remind me of Chile (similar coastline and climate).

About the mountains: as far as I can tell, there is very little effect on precipitation near the oversea high pressure centers. I'm not exactly sure why. The is nowhere in these areas where the mountains have higher precipitations, not even in the Atlas where the winds are blowing directly from the Mediterranean sea. Yes there is a major effect in Iran (for example) but it's only in winter when the high pressure system moves to the south, away from the Mediterranean sea. So the precipitation from the orographic lift should more or less follow the above image as well. It's clear that I painted every mountains without even thinking if it was supposed to be rainy or not. The orographic lift effect is completely wrong at these places.

[Charerg]

You're probably right about the cold currents. In the most recent version the "rainy area" reaches approximately 15 S latitude, which, if you look at Africa, is about where the Namib desert ends. All in all, I envision southwestern Eocidar as more or less comparable with Western Africa in terms of climate (in other words, not a desert, but not very rainy either for the most part). Considering that the African monsoon reaches all the way to the Sahel during the rainy season, I think the recent version is reasonable, with possibly the area west of Eocidar's "inner sea" a bit too wet in january, but it's hard to judge whether the precipitations are too high without seeing the climates themselves, since the equatorial latitudes mean a lot of evaporation even the areas with light rain are probably going to end up with a dry climate type.

Also, the Atlas mountains do receive rain during winter if I'm not mistaken? At least historically Northern Africa was "the bread basket" of the Roman Empire so it's not really desert (if not very rainy, necessarily). All in all, I think it's rare to find mountains with a true desert climate, except in the heart of the Sahara perhaps. So, I think a modest degree of rain along the mountain ranges during the "wet season" is justified. Although again, a bit hard to judge based on just the precipitation maps, I may have exaggerated the effect or made the rainy area too large.

[Azélor]

Western Africa ? which country exactly? Lagos got a very season precipitation pattern, dry winter wet summer. https://en.wikipedia.org/wiki/Lagos

The bread basket of the Empire was Egypt if I remember correctly, and although it is one of the most fertile land is the world, it barely rains.

It would make sense to have dry mountains if the surrounding air is also dry, the water needs to come from somewhere.

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I edited the precipitation layer to include the orographic lift with the westerns mid latitudes drier, like I mentioned in the other post.

here are the results

[Charerg]

Egypt was another breadbasket, but Northern Algeria (to an extent) and especially Tunisia were also very productive (the former Carthaginian heartlands).

Anyway looking at the climate maps, I think the temperatures are probably fine now. Af climate looks overall a bit too widespread compared to Earth. That, and deserts are overall too widespread compared to the steppes. Also, you're right that southwestern Eocidar could be maybe a bit drier at places, though I think your version is a bit exaggerated since it's essentially nothing but desert (and the occasional tundra) almost all the way to the Equator. Also, the southeastern continent (Anapar) is too dry in both our maps, the deserts there should be largely confined to the interior since most of the continent isn't really in desert latitudes. I think the peninsula of Akanrias (the large southern peninsula in southern Eocidar) should be "somewhere in the middle", it's too dry in my version and too wet in yours. There also seems to be a few weird high-latitude steppes in my version that should really be D climates (guess I need to increase precipitation there further).

That said, I'm pretty satisfied how most of the map turned out. I think it will maybe take one round of further fine-tuning the precipitations and then the climate map should be "good enough" that it can be finished with some manual adjustments here and there. Btw, do you think Dc is a bit too narrow strip between the tundra and Db climates? It seems slightly thicker on Earth, although maybe it's just the differences in latitude.

By the reference to Western Africa I mean the area in general, there's a lot more BSh, Cwa and Aw than there are BWh, Am or Af. Although in my case the interior of the "supercontinent" will be inevitably largely desert, I think the intermediate steppe climates still cover way too little area compared to similarly dry areas on Earth.

In any case, my thanks for running the script, it spares me a lot of work not having to do all that manually!

EDIT:
I also think that the interior of the northernmost non-polar continent (called Neraduhr) should probably be "winter dry" because of the presence of vast glaciers to the north. It looks like some Dwb turned up in my map, which is good, but I still need to adjust the precipitations so the Dc climates in the interior are Dwc rather than Dfc. Do you think I'm right about this, or should it just be Df climate?

EDIT2:
Actually, I guess I do need the touch the temperature maps somewhat, since Cfc covers rather large areas in the northern half of the map (when they should be either Dfb or Cfb). Another question, do you think the island chain south of Neraduhr (the northernmost non-polar continent) should be Cfc, as it is now?

EDIT3:
Ok, here are the updated versions. I made the winters slightly colder in general (especially in the north, where I feel the Arctic glaciers would lead to more extreme winters), to make continental climates a bit more widespread. In places, I also ramped up the summer temperature a tier in order to eliminate Cfc climates (although I left some islands and mountains as Cfc).

In terms of precipitation, in general I tried to make steppe climates more widespread, and also to make the tropics less of "rainforest or desert". Southwestern Eocidar should be a bit drier now, with the desert more widespread, while the large equatorial area on the eastern side of the supercontinent (called Magatel) should have more BS and Aw (I hope). But we'll see how the results turn out. I think this will be the last "run of the script" unless there are some glaring problems, and the climate map can be finished with manual adjustments from here on out. The relevant maps are in the attachments.

Once again, many thanks for running the scipts for me (as well as otherwise spending a lot of time on improving my world)!

[mbartelsm]

Azelor, one question. When saving the monsoon climates, why do you choose only those two? wouldn't climates with more extreme variations also be considered monsoon?

EDIT: Would you also be interested in someone turning this into a PDF? I'm a graphic designer by trade and would be more than willing to turn this into a properly designed document (it's kind of hard to navigate it on the forum)

[Azélor]

Some steppes needs to be added manually between the humid climates and the deserts. A large band when it's a plain and a narrow one if there is an elevation. In some places, it makes the whole deserts dissapear.

The tundra at the equator is not wrong if you look at the temperature maps, which are both between 0 and 10. This is something to be expected at this altitude http://koeppen-geiger.vu-wien.ac.at/...al_2006_A4.pdf

Anapar, it make sense if there is really a high pressure center right next to it, but I'm not entirely sure of that.

Akanrias: my version but a bit drier sounds ok.


Dc: I think it's because you lack landmasses in the appropriate latitudes. In some places, the Db would turn Dc if it was not tempered by the ocean.

Dwc, increasing the precipitations in summer should be enough (summer 4, winter no color). Decreasing it further in winter, I'm not sure it's a good idea.
Btw, the w climates require to have their driest mouth to receive less than 10% of the wettest month. In summer, you would need one the two wettest category and in winter, you need one of the tree driest. So you need both extremes.

Of the Cc, only Cwc is included (because it's alwals located at higher altitudes, so it's rather easy to place).
Csc barely even exist in the real world.
Cfc is not on the map. Because the differnece between Cb And Cc is the number of months with a certain temperature and we don't know the actual temp since we are using average. Still, there is an unknown color it the north and I will investigate... I could be Cfc.

The north is mostly covered by tundra, Dfc and Dfb. And some Dfa, which is nice.