Ayesha World Map

[Tiluchi]

Moving along (hopefully there's nothing drastically wrong with my pressure system maps), I've come up with some rough maps of prevailing winds. They look ugly as sin viewed close up, but hopefully they get the job done. I've mostly modeled them after winds on Earth plus the guidelines in the tutorial- generally they follow the prevailing westerlies, ICTZ, etc., plus the patterns of winds flowing from high to low pressure, and cyclonic winds forming in certain pressure systems. But if there's one thing I'm good at, it's messing up while carefully following instructions, so critique is, as always, welcomed! :-)

For January:



And for July:

[Charerg]

I think they're ok, with maybe a few minor flaws. I guess the biggest one is that you have some continental high/low pressure centers in weird places. Those really require a pretty big landmass. Personally I tend to simplify these maps a little and just draw the ITCZ (which is the major low pressure zone in tropical areas), as well as the oceanic high pressure centers. Then, if there's a big continent similar to Eurasia I may drop a continental pressure center there, but that's about it. I tend to skip the polar areas as well, since the climate there is basically entirely dependent on temperature, so usually you don't need super-detailed information about the wind patterns. In any case, the climate in the 30-75 latitudes is usually dominated by the westerlies, unless you have something like the Siberian high going on (that is, a huge landmass).

Here's an example of my "simplistic version" for Ayesha's January (perhaps overly simplistic, it's not 100% accurate):



I usually tend to emphasize the oceanic pressure centers, since in reality the pressure difference tends to be greatest there (with the exception of the Siberian high, ofc). Also, they're probably the biggest factor affecting climate in the tropical areas. It's not that different from your version, but the big difference is that the ITCZ is not "actually" located on the Equator in January (or July, for that matter). See where it is located on Earth in January, for example:



You can see that in Summer the ITCZ makes a big southwards turn towards major landmasses which heat up a lot faster than the ocean (also, you can see how the cold currents have a big effect as well, they always cause a northwards turn). So, essentially in your case you have the continental low pressure centers and the ITCZ a bit mixed....essentially, they are almost the same thing. It's probably helpful to actually draw the ITCZ on the map, it helps to visualize the situation.

[Tiluchi]

Hi Charerg,

Thanks as always for the great advice and help! You're right of course about the ICTZ. I guess I was going for an overly "idealized" version that ignored how low-pressure systems would pull it southwards. I've made some new maps with that in mind. As for the continental pressure systems, I do see that on Earth there are some pressure systems that form over small-ish continents, such as South America and Africa in January (low pressure) or Australia in July (low pressure), such as in the map below.

Attachment 89723

So I've kept some but not all of the continental pressure systems I had. If they don't generally make a huge difference, hopefully it doesn't matter hugely one way or the other.

January:


July:

[Charerg]

Speaking from experience, I think you should still drop some of the continental pressure systems (apart from those that merge with the ITCZ). In general, I find it's much easier to create an accurate climate if you simplify this part, and just treat most of the continental pressure systems as essentially a continuation of the oceanic pressure systems/ITCZ. For example, take a look at Earth's July Winds and Pressures:



As you can see, the only real continental low pressure here is over Eurasia, and even that largely merges with the ITCZ, so you could just leave it undrawn (apart from the smaller center over Mongolia), and still achieve the same result. Basically, a good rule of thumb is that all continental low pressure centers should merge with the ITCZ, apart from "Asian Monsoon" type situation.

Regarding the continental high pressure centers, if you take a close look at the July winds (or the January I posted previously), you'll notice that they basically form a continuous belt around the Earth, indeed the South African high pressure areas basically represent the Atlantic and Indian oceanic high pressure centers merging (although the Asian monsoon may have an effect here aswell, not 100% sure). So, again you should (imo) treat all continental high pressure centers (again, with the exception of "Asia situation") as an extension of the oceanic high pressure centers.

This means that basically high pressure centers similar to the Australian one need to form a continuous belt with the oceanic high pressure centers. In your case, for example, I think during July only the SE continent (Habagatan) should have a high pressure center. The smaller continent (Timog) is located much further south than Australia, and imo wouldn't develop a high pressure center.

However, that said, I don't think your newest version is that bad. You could probably work with this, just be aware that there will likely be some areas that will look a bit weird, and you may have to revisit the atmospheric circulation as a result.

The reason I suggest simplifying it this much is that if you use your present wind patterns, there's a good chance the climates won't turn out right (depending on how much you actually use these maps to create the temperature and rainfall maps). For example, this area (being in desert latitudes, and having mountains to the west, creating a barrier between it and the ocean), should probably be desert/other arid climates:



However, you have a low pressure center sitting there in July, which would imply rainfall. Admittedly, the ITCZ can be situated over desert, without necessarily creating rain (if the air arriving there is already drained of water), but imo you would be better off moving the continental low pressure center southwards. Basically, put it in the middle of the ITCZ, unless you have the "Asia case", is my advice.

[Tiluchi]

Hi Charerg,

That's a good point, especially about that desert, since it's supposed to be a desert to begin with. Though the desert-ness has partially magical causes anyway. On your advice I've gotten rid of a few continental pressure centers, just to make my life easier- and also to avoid too many continental climates, as they tend to make things colder than I want them to be in the winter. I've started on the temperature maps, but I'm realizing that's going to be somewhat of a multi-day process, so for now I'll post my map of where currents affect the climate, to make sure I've got that more or less right before I get too far into the weeds with temperature.

January:



July:

[Charerg]

On a cursory inspection, the influence maps look okay to me (not a thorough analysis though, so I may have missed something).

[Tiluchi]

Phew! Finally finished with the temperature maps, at least for now. It's kind of fun, in a masochist sort of way, but I'm looking forward to moving on to other things for a while.

Here's January:


And July:


A few notes:

• Ayesha is supposed to be just a little bit warmer than Earth (I suppose I could argue it's because the North Pole is much more open and landless than on Earth, so there's less room for ice to accumulate). I've moved the warm temperatures about 5º or a little less polewards to reflect that.

• I have a stronger continental effect on larger continents (especially Malaki, the central one), since I'm assuming the continental climate is stronger the more continent there is.

• The very hot area in the center of the western continent (Kanluran) has a semi-magical explanation. It should be a desert anyway, but I'm making it hotter and dryer.

• I'm not sure if the extra-hot area in the middle of Malaki in July should be that hot on both sides of the mountain range that bisects it. Looking at Earth, it does seem like there's something similar but larger in East/Central Asia. But I'm not sure how much of a cooling effect the mountain range would have on the lowlands around it.

• Also not sure if I overdid the temperature difference in the high mountain ranges in Habagatan (southeastern continent) and Kanluran- they're similar to the Andes in height, but generally further poleward.

• Would there be a slightly cooler area on the southeast coast of Silanganan (northeastern continent) because it's next to the ocean? There's some sort of warm current from the ocean affecting it, but I'm not sure what effect those land shapes would have. The closest parallel I can find is the southern US, which doesn't seem to have cooled down much from being in a coastal zone.

Anyway, in the meantime I'll be working on precipitation maps. Looking forward to actually determining climates soon!

[Azélor]

i think it looks fine so far.

how much of a cooling effect the mountain range would have on the lowlands around it.

None, and actually, being surrounded by mountain ranges can have the effect of trapping the heat at low altitudes like in Iran. But being at the foot of the mountains facing the ocean means that it's shielded from the heat waves coming form the continent interior.

The precipitation is the clunkiest part but better that than no guidelines at all I suppose.

[Charerg]

Yeah I guess the temperatures are ok. Actually the tropical areas look a bit cool during the summer if anything, if you're going for a warmer climate than present-day Earth. Although that may be just that I'm mislead by the colour code, I'm too used to seeing/using the colours from Azelor's tutorial. Actually, doesn't the script require that you use those exact colours in order to work?

[Azélor]

Yeah I guess the temperatures are ok. Actually the tropical areas look a bit cool during the summer if anything, if you're going for a warmer climate than present-day Earth. Although that may be just that I'm mislead by the colour code, I'm too used to seeing/using the colours from Azelor's tutorial. Actually, doesn't the script require that you use those exact colours in order to work?

Yea, I forgot to add this in my last message. The script is using specific colors and the margin of error is pretty slim.