Planning the climate and ecosystem (WIP)

[Elterio Delgard]

So I finished working on my sketch for winds and sea currents, as well as the heights for the two mountain chains.
Climates.gif

[Azélor]

Thanks Azelor, but when I was saying that my map was about just South of the great lake, i was talking about the page with the two mountain chains and the valley, so would be like one page up. However, your insight is aweseome though. I am starting to work oin it now.

Alors ça change tout.

[Robulous]

It's hard to work out the climate with just a symbolic map rather than a terrain map. It seems unlikely that the land between the mountain chains would be sea level, they're more likely to be upland plateau (eg Tibet or Xinjiang). British Columbia also mostly lies between two sets of mountains.

It's unusual for a whole mountain chain to be so high that no clouds at all can pass over them. If so the region between would be desert.

[Elterio Delgard]

It's hard to work out the climate with just a symbolic map rather than a terrain map. It seems unlikely that the land between the mountain chains would be sea level, they're more likely to be upland plateau (eg Tibet or Xinjiang). British Columbia also mostly lies between two sets of mountains.

It's unusual for a whole mountain chain to be so high that no clouds at all can pass over them. If so the region between would be desert.

Mmmmm Now I have to think about that big river going through the valley... If the two mountain chains prevent clouds from passing, then rain cannot fall so therefore what will keep my river???
I could say that snow on the mountains will melt but that wouldn't work well... I guess I must open a path for rain clouds.

Concerning the level of the ground between the two mountain chains, I agree that they should get higher as it goes South (to a certain extent of course). That would explain why the river has to go way north instead of west. On the other hand though, this means that the southern desert wind will have a hard time to blow up a slope, unless it is progressive.

Now, should I try to keep that river or should I remove it?

[Azélor]

It's hard to work out the climate with just a symbolic map rather than a terrain map. It seems unlikely that the land between the mountain chains would be sea level, they're more likely to be upland plateau (eg Tibet or Xinjiang). British Columbia also mostly lies between two sets of mountains.

It's unusual for a whole mountain chain to be so high that no clouds at all can pass over them. If so the region between would be desert.

I did some calculation about that a while ago. Water fall back on the ground after it reaches the dew point. When the airmass starts the elevate above the mountain range, the air cool at a rate (lapse rate) between 6 and 9 degrees for each 1000m of elevation. 6 if the environment is wet and 9 if it's dry. That said, once the temperature drop below a value close to 0°C (not exactly 0 but I don't remember) the effect of lowering the temperature even further has only a marginal impact on the precipitations. Consider you airmass like a sponge. At a high altitude, it gets squeezed really hard. Most of the water has fallen but it's still humid. If you what the rest of the water to fall, you need to squeeze it at least as hard as you just did. That means that it's unlikely to to reach the dew point unless you lower the temperatures again.

Considering an average lapse rate of say 7°C and that an average land if temperature of 30 is considered pretty high (based on monthly average), the temperature will reach 0 at the altitude of 4286m.
This is a simplification of the reality since I'm not taking in account all the variables.
Of course, I need to add that the air pressure also need to be taken in consideration. If I remember correctly, the dew point is not the same at sea level and at high altitudes since the pressure is different.

So, the first slope is rainy, the opposite one is dry as well as the valley below. The other slope above the valley might have rain from time to time.

[Elterio Delgard]

I did some calculation about that a while ago. Water fall back on the ground after it reaches the dew point. When the airmass starts the elevate above the mountain range, the air cool at a rate (lapse rate) between 6 and 9 degrees for each 1000m of elevation. 6 if the environment is wet and 9 if it's dry. That said, once the temperature drop below a value close to 0°C (not exactly 0 but I don't remember) the effect of lowering the temperature even further has only a marginal impact on the precipitations. Consider you airmass like a sponge. At a high altitude, it gets squeezed really hard. Most of the water has fallen but it's still humid. If you what the rest of the water to fall, you need to squeeze it at least as hard as you just did. That means that it's unlikely to to reach the dew point unless you lower the temperatures again.

Considering an average lapse rate of say 7°C and that an average land if temperature of 30 is considered pretty high (based on monthly average), the temperature will reach 0 at the altitude of 4286m.
This is a simplification of the reality since I'm not taking in account all the variables.
Of course, I need to add that the air pressure also need to be taken in consideration. If I remember correctly, the dew point is not the same at sea level and at high altitudes since the pressure is different.

So, the first slope is rainy, the opposite one is dry as well as the valley below. The other slope above the valley might have rain from time to time.

O...okay... Trying to understand but having a hard time here. So if I understood well the little I did, for the western mountain chain, it will be a cooling of 6 degrees per 1km, which means with my map a total of 24 where the clouds are to get past. Mmmmm.... I guess I will need to find a way to make sure that the winds from the west are warm enough! And not just that, but if the dew is the only possible source then the river will be most likely a seasonal one, when its at the warmest... Well, I guess I could always lower the western mountain chain to 3km at that area, which would be a cooling of 18 degrees.

However, I could always make it snow on the mountains and it would melt with the hot Wind of the South, giving in turn water to keep the river going.

[Elterio Delgard]

Okay, here is a redrawn version of two maps put together.
Sorry for the quality of the scanning... I am really bad at it...
Nouvelle image bitmap (2).jpg

[Azélor]

O...okay... Trying to understand but having a hard time here. So if I understood well the little I did, for the western mountain chain, it will be a cooling of 6 degrees per 1km, which means with my map a total of 24 where the clouds are to get past. Mmmmm.... I guess I will need to find a way to make sure that the winds from the west are warm enough! And not just that, but if the dew is the only possible source then the river will be most likely a seasonal one, when its at the warmest... Well, I guess I could always lower the western mountain chain to 3km at that area, which would be a cooling of 18 degrees.

However, I could always make it snow on the mountains and it would melt with the hot Wind of the South, giving in turn water to keep the river going.

Well, to answer your concern, that was only based on the average temperatures. But in mid afternoon, the temperatures are probably going to be higher than that, but I don't know by how much exactly. Just keep in mind that the diurnal temperature range are smaller in an humid area compared to a desert. So depending on the temperatures and the height of the mountains, it's possible to have precipitations on the mountain slopes inside the valley that are facing the winds. The valley in between is going to be really dry unless you lower the range by a larger margin. But, it does not mean that the area is a desert. It has a desert climate sure but the surrounding precipitations might make it livable. Like Isfahan, Iran.

The river is likely to be a seasonal one with a low during winter, unless it can also collect the water from less dry areas too.

[Elterio Delgard]

Mmmmmm... Interesting... I might have to lower as you said the western mountain range. I cannot allow that river to be entirely seasonal, but maybe I could have it behave like the Nil in Egypt. Would allow a dry but rich environment. The thing is that I plan on having a unique ecosystem because the Dark Emperor will be playing with skeletons of dinosaurs. (I will replace dragons by dinos!)

The problem with the climate of the valley will be the chilly nights. Well, the Dark Emperor will working on that for several centuries so he could as well find a solution for that eh?

Now, I expect the river to be quite rich in nutrients for forests, which will explain why there is such a flourishing forest on the Assionian Empire map.

[Elterio Delgard]

Well, here goes again! This time it's not about the climate but about hydrography and planning how to draw some great lakes.
Here is the map:Evozen 06 001.jpg

I feel like the great lakes are unnatural, too close to the sea and not justified by any depression that would allow so many rivers to flow in...
I hope to be able to keep them and allow some flourishing kingdoms (well, flourishing being relative...) all around it. I know that from the south there are some big mountains, but the main river goes East as you can see on my preivous maps...

-Would more mountains allow it?
-Would justifying it with the leftover of an icecap do sufficent pressure on the earth crust to lower the ground even this close to the sea?
-Maybe a meteorite, but the lakes are two long and thin I guess...