Rheia: one final try at ground-up worldbuilding

[Tiluchi]

I believe there is a similar Discord like this called Weldholm (formerly associated with the mapnaking reddit). There are a lot of people doing this kind of mapping on there.

I should have known that someone would have gotten there first! ;-) Do you happen to have a link for it? I wasn't able to find anything by searching Google or Reddit.

I'm currently chugging along with ExoPlaSim runs and can get a T42 resolution model (64 x 128 px) to converge in about 20 - 24 hours compute time; I'd be happy to give your world a go (for free!) if you're interested. There are definitely some systematic errors - my general thinking is that the best approach is to manually modify the temperature / precipitation outputs and then feed those into the tutorial here rather than rely solely on the climate maps generated from pure ExoPlaSim data - though I also think it offers the ability to capture effects we might not be able to immediately predict based on our N = 1 data point of earth.

That would be amazing! I'll follow up via DM.

It seems you got down the ocean currents, so that's great. I'm exciting and intrigued on how you will tackle the pressure zones and climates! Are you going to do it simple like the Pasta, or are you going to do it complex like the other worlds and like Earth?

Man, why you gotta do me like that Woody? I had some nice, simple pressure and wind maps ready to go based on the Pasta tutorial, and this reminded me that they really are quite simple to the point of abstraction. Which maybe is fine for climates but I do enjoy getting into the finer details of things. Decided to go ahead and do a more detailed wind and pressure maps, which I'm attaching here. Maps are based on real-world data, plus the helpful suggestions in the Azelor and Pasta tutorials. Definitely welcome any feedback on these, as a good amount of guesswork was involved for figuring out the locations of pressure zones, the ICTZ, wind direction, etc. Not too worried about the polar areas since that's all just going to be very cold anyway, but as always with this sort of thing the subtropics are where things get complicated...

[WoodytheClimateGuy]

Nice dude. So, how did figure out how the pressure zones worked? Like, how did you figure out the locations and strengths of them?

[WoodytheClimateGuy]

Hi all!

This isn't my first started thread here, and most of my other posts have been similar projects: working on worlds from plate tectonics on up, in order to have a reasonably realistic world geography. Have started this twice before here and stopped both times due to not being satisfied with the general realism of the world's geology or the direction it was going. Nikolai Hersvelt's amazing posts over at Worldbuilding Pasta were enough to get me to give it another try with the new tools that are available, and I've finally progressed far enough to be much happier with where this is going in terms of aesthetics and realism. Figured I would post my progress here in case the workflow is useful to others considering similar projects.

Previous attempts started with a present-day world map, and working backwards with plate tectonics to get something reasonably plausible. This works as far as it goes, but I found it difficult to justify present-day positions of continents and plate boundaries with any kind of detailed history. After a fair amount of frustration with that I turned to the Worldbuilding Pasta tutorial, constructing a complete geological history of a world for about 800 million years until the present day. That worked better from a realism standpoint, but it presented the opposite problem for me: starting that early means the world tends to take on a mind of its own, and I ended up with a final geography that I wasn't particularly satisfied with (unfortunately, I only realized this after almost a year of working on tectonics and then topography). For those who are somewhat agnostic about the final geography and/or don't care as much about realistic biogeography, this is probably still the best way to go.

Ultimately I ended up going with a little bit of a hybrid approach: I made a very, very basic sketch of how I hoped things would look in the present day, then did a GPlates history going back about 400 million years. I chose this for two reasons: first, because tectonic events older than this generally have little to no influence on present-day topography, meaning that I could still feel pretty confident about realism. Second, because this means only going through one supercontinent cycle, allowing me more control over the final geography while still giving lots of geological detail. It also allowed me to get even more detailed with things like terranes and microcontinents than the Worldbuilding Pasta example, close to how things worked on Earth. (note also that our understanding of Earth's plate movements older than 400 million years ago is sketchy at best, so I wasn't too worried about losing important details)

A gif of the last 420 million years of plate tectonics is below (sadly compressed to all hell to make it a small enough file for the CG site). I'm lazy and technologically inept so this is just a screengrab from GPlates, without a tracker of the number of years- just know that it starts at 420mya and ends at the present day.

Attachment 133542

Attachment 133545

A few weeks of work on plate tectonics leaves me with the present-day map below. The little empty polygons in the middle of continents are cratons, black is active continental orogenies, orange is active volcanic orogenies (my worldbuilding requires distinguishing between igneous and sedimentary rocks in the present day), grey and yellow are former orogenies, purple is large igneous provinces, and light blue is oceanic plateaus. Obviously these are just guidelines (and the "continents" are actually continental shelf rather than dry land), and I still have a fair amount of leeway for making coastlines and topography for my liking.

One question here. How did you move the mid-ocean ridges for the new oceanic plate? Do they have their own plate ID, or are they Half-Stage Rotations?

[Turambar]

I should have known that someone would have gotten there first! ;-) Do you happen to have a link for it? I wasn't able to find anything by searching Google or Reddit.

Here you go. This link should last 7 days I think. https://discord.gg/2haP93es

[Tiluchi]

Nice dude. So, how did figure out how the pressure zones worked? Like, how did you figure out the locations and strengths of them?

Honestly it was mostly looking at the images of Earth's January and July pressure systems that Nikolai posted on the climate tutorial, along with the guidelines in the Pasta and Azelor tutorials. Since I'm pretty familiar with my world's topography at this point, I can guess at what seems to drive high and low pressure systems, and go with that.

One question here. How did you move the mid-ocean ridges for the new oceanic plate? Do they have their own plate ID, or are they Half-Stage Rotations?

Yup, half-stage rotations, I think I just used the technique that's in the Pasta GPlates tutorial. The mid-ocean ridges were easy, what was a pain in the behind were the flowlines, which seem to shift away from their initial positions at random with no rhyme or reason. Annoyingly enough still necessary for guiding plate motion and figuring out ocean crust, but I'm glad not to have to repeat that again.

Here you go. This link should last 7 days I think. https://discord.gg/2haP93es

Thanks Turambar! Just joined, looks like a great community.

[Tiluchi]

Steaming right along, I've got first drafts of the temperature maps for January and July, mostly based on the Azelor tutorial. The Pasta tutorial mostly uses input from ClimaSim (or in later iterations ExoPlaSim), which as has been discussed here and on other threads seems to get some important things wrong with regards to temperature, particularly on large continents and in polar regions. MrBragg has kindly agreed to run my maps through ExoPlaSim however (thanks again mate!), so it will be interesting to see how the outputs compare. I figure the final maps I input into the Gimp script will be some combination of the map done by hand and whatever ExoPlaSim spits out.

Attaching here the temperature maps for January and July, as well as the temperature zones à la the Azelor tutorial in case that's useful. Also attaching a greyscale image for MrBragg as apparently sending images over DM is difficult...

[Harrg]

I decided to play a bit with your heightmap. Unfortunately, the extension is too small, so the pixels are visible

[Tiluchi]

Awesome stuff Harrg! I tried fiddling around with lighting effects and a full-sized greyscale image a couple days ago and was surprised at how good it came out without too much effort on my part. The main issue is spots where the contour lines are spaced far apart, which gives the shaded relief and awkward "stepped" appearance. I masked those bits with a gaussian blur, but obviously there's more tweaking that needs to be done before I have something I'm really pleased with. Will probably also need to do multiple lighting effects layers with the light from different directions depending on the orientation of the mountains.

Anyway I'm putting that part on hold for now until I finish doing my climates, but once I do get back to it I'll probably be asking you for some tips on your technique... posting what I have so far although agin, lots more work is necessary. Honestly though, seeing that all my work drawing the elevation by hand resulted in something that looks surprisingly realistic made me feel much better about my artistic choices so far with this world.

[WoodytheClimateGuy]

Yup, half-stage rotations, I think I just used the technique that's in the Pasta GPlates tutorial. The mid-ocean ridges were easy, what was a pain in the behind were the flowlines, which seem to shift away from their initial positions at random with no rhyme or reason. Annoyingly enough still necessary for guiding plate motion and figuring out ocean crust, but I'm glad not to have to repeat that again.

If it's a half-stage rotation, then what the two Plate IDs that control the rotation?

In addition, how do you import your mountains into Wilbur (which I'm assuming is the reason why they're so detailed)? I use Adobe Illustrator to make my mountains, so is there a method to this?

[WoodytheClimateGuy]

Steaming right along, I've got first drafts of the temperature maps for January and July, mostly based on the Azelor tutorial. The Pasta tutorial mostly uses input from ClimaSim (or in later iterations ExoPlaSim), which as has been discussed here and on other threads seems to get some important things wrong with regards to temperature, particularly on large continents and in polar regions. MrBragg has kindly agreed to run my maps through ExoPlaSim however (thanks again mate!), so it will be interesting to see how the outputs compare. I figure the final maps I input into the Gimp script will be some combination of the map done by hand and whatever ExoPlaSim spits out.

Attaching here the temperature maps for January and July, as well as the temperature zones à la the Azelor tutorial in case that's useful. Also attaching a greyscale image for MrBragg as apparently sending images over DM is difficult...

I have a question here; what is your method of making the temperatures? What is your process? I'm have a really hard time understanding Azelor's tutorial.