WIP (sort of tutorial to be) : Climates, applying Geoff's Cookbook at detail (some)

[Pixie]

Thanks for your time, Azelor. You've pointed out some important stuff, namely, that I am ignoring the interaction between temperature and "wetness" when considering how dry is a climate. I think the desert/steppe/continental "gradient" will have to be a little reviewed.

The point of this whole system, however, is to skip numbers - this is not because of laziness, but because there are so many "educated guesses" and approximations when it comes to a fictional planet-system that the uncertainty of any number is absurd. I mean, what's the point of saying a given place has a mean temperature of 25 ºC if the margin for such figure is.. say.. 30%. So, that's the rationale behind a fully graphical method, just to explain myself. Of course, you can throw a guess about what exactly "Very Hot", "Hot" or whatever means. I can agree with your guess without second thoughts.
I also want to make this tutorial easy enough for those without a science background - as much as that is possible - and that is why I am trying to define clear and easy to follow rules. Even to the point where some accuracy is lost. I'm not sure how this balance will work out.

Now, as for your valuable comments.

BSh and BSk: small detail but it's S and not s, otherwise it mean summer dry
these two climates can have a rainy season, some places could receive up to around 200mm of rain in a month because they are subject to the monsoon (mostly the hot one). Large parts of the steppes in Africa and Eastern Asia are affected. Examples include Niamey and Hohhot.

So, I will probably have to review some of the combinations. Say, if a region is Very Hot/Hot in a season and Low in wetness, that roughly equates to "Dry" - and it would still be desert. Do you agree with this generalization?

BSk : is usually found at higher altitude than the hot desert

Dont forget that : (I know it's pretty complicated!)

B. Dry climate: Annual evaporation is greater than precipitation (also called potential evotraspiration). To determine whether a location has an arid climate, the precipitation threshold must first be determined. The threshold value (in millimetres) is determined as:
• If less than 30% of annual precipitation occurs in the summer : Annual precipitation (mm) < 20 × average annual temperature (°C)
• If more than 70 % of annual precipitation occurs in the summer: Annual precipitation (mm) < 20 × average annual temperature + 280
• Else : Annual precipitation (mm) < 20 × average annual temperature + 140

o If annual precipitation is < 50 % of the threshold = BW: desert climate
o If annual precipitation is between 50 and 100 % = BS: steppe climate

Altitude is already factored in as one determines wetness maps and temperature maps, so Cold Steppes should appear naturally when a Hot Steppe region is in altitude (and it does in my tests). As for the numbers, I am aware of those, but as I explained I don't think I can bring formulas to this system (Geoff's Cookbook avoided it too).

So the steppe climates can be more or less rainy if the evaporation is very high too. The same principle stand for colder climates too. They receive much less rain than hot climates but are still considered wet because the evaporation is much lower.

As I said, I'll review where some of the combinations fall into, namely between cold steppe and continental (C's and D's) and between hot steppe and mediterranean.

(detail) Also, according to the classification, it's possible to have cold winters in BSh as long as the average yearly temp are high enough. Rare but possible

(detail) BWn: it's an additional class for desert near water that have a small temperature variation like Namibia. I was considering incorporating it

Thanks for these details. I didn't know BWn classification. As for the detail about the BSh, if we don't mention it in "the rules", a piece of hot steppe will be classified as cold steppe, if we mention it, the rule gets more complicated... a choice affecting balance between accuracy and friendliness...

Csb: monthly temperature never go over 22, so it's not hot and not cold either because it never go below 0 (monthly)
I just like to specify that Csc form usually at higher altitudes at it's not very common

This was definitely a choice I made towards friendliness. Merging Csb and Csc allowed for Cold winters. In my tests this covered highlands close to Mediterranean proper (Csa) more than areas immediately poleward of Csa, but it might be a peculiarity of the continent I used. That's why I will have to try this system in different continents.

Cwb/Cwc: monthly temperature never go over 22, so it's not hot and it's even colder for Cwc, they are located at higher altitudes

I get your point but, the thing is, how would you classify a region with Hot summers (over 22) and Cold winters, with sufficient wetness (that's "moderate" or above in the current rules). However, I see Hot+VeryWet Summers with Cold/LowRain Winters falling a bit awkwardly into Cwb - can you find a better fit?

D climates: if I have the temperature right for the extreme cold, it should only be applied with : Dfd, Dwd, Dsd and the other colder climates. I tried to find other climates in the D group with winter months under -38 but I could not.

So, the consequence of this is that all regions with an Extreme Cold temperature should strictly be Taiga or Tundra?

Dfa,Dfb: you inversed the summer and winter precipitations.

Thanks... fixed! (wish all fixes were these simple

As I said, thank you for the help. There's a few questions in the middle of my replies, did you spot them? As for temperature and rain charts, you can see them in a previous post, I have the four side by side when explaining how to "find climate zones".

[Azélor]

You’re probably right, we are just amateur for the most part so using real numbers will only make the process more complicated for a little gain in precision. And most people won’t notice it.
Obviously, if I’m trying to make it simpler, I’m heading in the wrong direction !

So, I will probably have to review some of the combinations. Say, if a region is Very Hot/Hot in a season and Low in wetness, that roughly equates to "Dry" - and it would still be desert. Do you agree with this generalization?

I’m not sure I understand the question. My main point was to say that in Koppen classification ‘’S’’ and ‘’s’’ are two different things.

S: second letter that indicates a steppe and only usable with first letter B
s: also second letter but mean that the summer is dry. Maybe it’s possible to use it with B but for some reasons, it does not apply to deserts BW (because it rarely rain anyway) or steppes BS.

Very hot and dry season = desert or steppe

Since monsoon only occurs in summer the very hot season, it’s impossible to have a monsoonal climate with a hot and dry summer but wet winter. The only that comes to mind is AS but the dry season is only considered dry because the wet season is really rainy. So it’s not that dry.

So it’s either a hot desert or it could also be a hot semi-arid. He does not have to be subject to the monsoon. And if it’s not affected by monsoon, the wet season is also the coldest.
So it means there are two types of hot arid climates, with different precipitation pattern, nice…

So, the consequence of this is that all regions with an Extreme Cold temperature should strictly be Taiga or Tundra?

I guess so. Extreme would not be extreme if it applied to a large part of the world.
This is about the coldest I've found in Dfc, Dwc, Dsc Krasnoyarsk Krai - Wikipedia, the free encyclopedia
Don't forget that the number are based on the monthly average. For example, it's possible to have a temperature of -50 in Manitoba (Dfb) or Mongolia but that's way below their average.

I get your point but, the thing is, how would you classify a region with Hot summers (over 22) and Cold winters, with sufficient wetness (that's "moderate" or above in the current rules). However, I see Hot+VeryWet Summers with Cold/LowRain Winters falling a bit awkwardly into Cwb - can you find a better fit?

Well to start of, there is probably just one place on Earth with a Cwc climate based on the wiki map. Can you find it just by looking at the map ?
It's possible to have it cover a larger area in a fantasy map but it won't be much. But you question is how to classify this climate ? :

Summer: Hot, very wet
Winter : Cold, dry

Dwa maybe ? It's affected by the monsoon but I'm not sure it's wet enough

As for temperature and rain charts, you can see them in a previous post, I have the four side by side when explaining how to "find climate zones".

Really? I mean the 2 central parts are really dry. But I can't say if you did something wrong with the precipitation pattern because that part is really hard for me.

[vorropohaiah]

now this is my kind of thread - just leaving a comment here to make sure im subscribed and to say good work! wish i had the paience to do this with my own world

[Pixie]

Thanks for support, vorropaiah

Now, let's keep the discussion going - the "rules" to identify climate zones are far from finished.

I’m not sure I understand the question. My main point was to say that in Koppen classification ‘’S’’ and ‘’s’’ are two different things.

Very hot and dry season = desert or steppe

I got that, Azelor, my point is about the rule-set I am devising.
In it, a region that gets rain ("Low" level, but still, different than "Dry" level) in any of the seasons doesn't get classified as Desert but as Steppe.
From our discussion, I take it that a region which has a "Low level" of rain but during a "Very Hot" or "Hot" season, should still be qualify as Desert.

Or (a different solution I am also considering).... once the temperature map is finished, use it to reduce the rain level in the Wetness maps in the areas where seasonal mean temperature is "Very Hot". Maybe this would yield the same result and be easier / more graphical.

Since monsoon only occurs in summer the very hot season, it’s impossible to have a monsoonal climate with a hot and dry summer but wet winter. The only that comes to mind is AS but the dry season is only considered dry because the wet season is really rainy. So it’s not that dry.

So it’s either a hot desert or it could also be a hot semi-arid. He does not have to be subject to the monsoon. And if it’s not affected by monsoon, the wet season is also the coldest.
So it means there are two types of hot arid climates, with different precipitation pattern, nice…

I see what you mean. I should split my current rules for Am between proper monsoon and chaparral-style climate (long dry summer plus a really wet but short season).

Well to start of, there is probably just one place on Earth with a Cwc climate based on the wiki map. Can you find it just by looking at the map ?
It's possible to have it cover a larger area in a fantasy map but it won't be much. But you question is how to classify this climate ? :

Summer: Hot, very wet
Winter : Cold, dry

Dwa maybe ? It's affected by the monsoon but I'm not sure it's wet enough

Dwa it is!

Really? I mean the 2 central parts are really dry. But I can't say if you did something wrong with the precipitation pattern because that part is really hard for me.

Yeah, I didn't anticipate it either. But (you can see the detailed, but already slightly outdated heightmap in here), both inland cores (north of the equator and south of the equator) are in the rain shadows of very large mountainranges and fall into desert latitudes. And I had a industrialized nation in it at start.... (they're dead now)

[Corvus Marinus]

I'm really happy to see that you've updated this. I'm moving to the Republic of Georgia in August (for a short-term teaching job), and so am at present very busy getting ready for that, but I look forward to implementing your latest instructions whenever I find time. Keep up the good work!

[Azélor]

I need to go back at what I said about Cwb/Cwc:

They are indeed different but the simplifications you made abolishes these differences since they fit in the same temperature categories. The only difference is : Cwc is colder (but that should be obvious)
I suggest that you just ignore it.

but here's the details in case your curious:

Cwb
• Average temperature of the 3 coldest months between 0 °C and 18 °C
• Average temperature of the 4 hottest months between 10°C and 22 °C


Cwc:
• Average temperature of the 3 coldest months between 0 °C and 18 °C
• Average temperature of the 3 hottest months between 10°C and 22 °C
• No more than 3 months with average temperature > 10 °C

[Pixie]

I think we are now at the same page, Azelor, concerning simplifications.

At present, Corvus Marinus is in the latest stage of this scheme of work, and ascanius and I are testing it as well with this map.

I also want to further test it with real-earth map in order to compare with real-earth climate zones, but for some reason (the plain fear of realizing that I have it all wrong) I didn't start yet.

Once all this testing and the fine-tuning I am doing with you is completed, this can become a real tutorial (as in a pdf at the tutorials section). Do you agree?

[Azélor]

Yes it would be a great tutorial !

also, you can check here and give me your opinion about my... simplification:
http://www.cartographersguild.com/re...i-hope-so.html

[Azélor]

So, what I think of your climate map now that my document is done... It looks pretty good but the sheer number of elements to consider open some room for choices, and mistakes.

I have some points that I would like to discuss:

1- The eastern hot steppe seems really dry for a place close to the equator that faces the major winds from the ocean. The mountains are not that high, so I think it's too dry, except for the southern tip.

2- The eastern side of the cold highland desert should be really wet, probably the wettest place on the map. Not only have they received water like the nearby tropical forest but also because of the orographic lift. It reminds me of the region near Nepal, north-east India.

3- it’s unlikely that you can have a D climate on that map except maybe on the southern part of the continent (the cold steppe plateau) maybe but not on an island. The climate is much more temperate and less extreme because it’s surrounded by water. It’s probably Cfc

Lastly, like I said to Corvus, Mediterranean climates are close to the sea. they could still be located not too far inland but one of yours if hidden behind a mountain range.


Overall it's pretty good!

[sangi39]

I've been largely inactive for the last two months* but looking at this thread, Azelor's recent thread on Koppen climate zones and the work done by several users regarding tectonics, I might have to restart my work on Yantas. As much as I like the current look, I feel like I kind of rushed the tectonic stage and I never really dealt well with Geoff's climate tutorial.

*I've recently separated from my wife (mutually), moved back in with my mum and brother, blah blah blah) and gotten so tired of doing almost anything (needed to see a counsellor about stuff). Hectic couple of months really