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Qwynegold
10-04-2009, 01:53 PM
I'm working with this map:
On second thought, check the thumbnail at the bottom of the page instead, the page got too wide when I posted the full-size image.
I know it's full of mistakes and **** (like way too many hotspots), but it's like a practice map I'm making before I start working on a real conworld map. The next thing I need to work on is the climate. On this map, the water currents are already marked with arrows (blue for cold water, red for hot), but I think I need to mark the wind pattersn, like in these maps:
http://www.cartographersguild.com/attachment.php?attachmentid=17388&stc=1&d=1254678307
http://www.cartographersguild.com/attachment.php?attachmentid=17389&stc=1&d=1254678307
I guess I need to mark the low and high pressure areas first, because the winds depend on them. But I have no idea how to go about doing that. I mean, where should these different pressure areas be? Can anyone help? The planet is just slightly smaller than Earth, I don't remember the exact size and can't seem to find my notes, but it's like 39,980 km across the Equator or something. It's similar to Earth in all other aspects as well. Um, I don't know what else you need to know about the cosmology in order to answer my questions, but just ask me whatever you need to know. Though, I haven't really decided much about the planet. :?:

I tried searching for "climate" on this site, but couldn't find anything relevant. I also looked through a few pages of the tutorials section, but it was just too much to look through everything.

Jeff_Wilson63
10-04-2009, 03:24 PM
On this map, the water currents are already marked with arrows (blue for cold water, red for hot), but I think I need to mark the wind pattersn, like in these maps:
OK. First on currents.

On a spherical rotating world ocean currents are driven by the world's rotation. The explanation for this gets rather technical, dealing with inertia and relative rotations, but the effect the easy: All else being equal, currents flow clockwise in the northern hemisphere and counterclockwise in the southern hemisphere. An ocean straddling the equator will have a major current at the equator heading from east to west and currents on its north and south boundaries heading from west to east.

Of course "all else being equal" is rarely the case. :D To accurately map currents you should begin with the largest water distance along a line of latitude. Keep in mind that once all that water starts flowing it has to go somewhere and you can map the lines of flow.

Your existing map looks pretty good. I might change some things, but currents can do some really strange things. (Particularly, that eastern flow above your western equatorial continent doesn't look right to me. I'd think the equatorial current to the west would tend to "pull" water out of that sea.)

Jeff_Wilson63
10-04-2009, 03:59 PM
In dealing with wind patterns as a mapper or world creator, you first have to realize that the way meteorologists look at the world isn't helpful. Maps intended to convey information to a meteorologist need to be reinterpreted to be useful to a world creator.

As with ocean currents, air on a spherical rotating world tends to flow clockwise in the northern hemisphere and counter-clockwise in the southern hemisphere. Those patterns are disrupted as water evaporates and condenses. On a world scale, evaporation encourages evaporation and condensation encourages condensation. An area of evaporation brings air in along the surface then pushes it up and out high in the atmosphere (a high pressure zone). An area of condensation pulls air in from high in the atmosphere and pulls it down and then out along the world's surface (a low pressure zone).

Now, while the flow of air high in the atmosphere holds fairly constant, the effects near the surface are subject to effects from the ground, particularly mountain ranges. (Individual mountains don't have much affect on their own.) Mountains won't block the flow of the air, but they will distort and slow it.

To place global wind / weather patterns, you first need to be sure of your ocean currents and mountains ranges. Once you are sure of those aspects, create 4 maps, one for each equinox and solstice. Start with the map representing summer in the hemisphere you make your make your home, and place your major areas of evaporation. These areas will center the winds which match the natural deosil movement of the air in that hemisphere. Having placed your major evaporation zones you can place your major condensation zones. Winds around these zones will flow widdershins (counterclockwise in the northern hemisphere, clockwise in the southern hemisphere). Repeat for your other maps in seasonal order.

I hope this (and the previous) helped. It's a very complicated subject, but I hope I supplied enough information to get you started.

Qwynegold
10-04-2009, 04:30 PM
An ocean straddling the equator will have a major current at the equator heading from east to west and currents on its north and south boundaries heading from west to east.

On a map I have, it seems to be exactly the opposite in the Pacific Ocean. :?:

I'll make some changes, at least to my currents on the northern polar sea, and then reply to the rest of the stuff...


Your existing map looks pretty good. I might change some things, but currents can do some really strange things. (Particularly, that eastern flow above your western equatorial continent doesn't look right to me. I'd think the equatorial current to the west would tend to "pull" water out of that sea.)
The two red arrows going from NE to SW that are between the two equtorial currents?

Jeff_Wilson63
10-04-2009, 05:01 PM
Er, you've reversed directions. East is on your right looking at the map, west is on the left. It's even labeled that way on your map.

I have problems with directions myself, so I know how this can happen.

Qwynegold
10-05-2009, 08:50 AM
Er, you've reversed directions. East is on your right looking at the map, west is on the left. It's even labeled that way on your map.

I have problems with directions myself, so I know how this can happen.

Wait, wait, wait, wait, what? Isn't it like this?:
http://www.cartographersguild.com/attachment.php?attachmentid=17413&stc=1&d=1254746908
(sorry about the crappy quality, my scanner doesn't work with this computer I'm using, so I just took a quick photo).

Jeff_Wilson63
10-05-2009, 01:52 PM
Interesting. What book is that from?

Countercurrents exist everywhere. (There's actually a quite important one running directly east of the Gulf Stream.) However, from a climatological standpoint they're insignificant. Even if you plan to deal with sea travel or fishing economies, it's easier to just assume that countercurrents are just there than to indicate them on your map. That countercurrents exist doesn't change the main mass of the water flow.

Stuff like the northern Indian Ocean and the arctic currents are why you need to map your largest masses of water first.

Qwynegold
10-05-2009, 05:09 PM
Interesting. What book is that from?
It's from a big-ass atlas called Geographica.


Countercurrents exist everywhere. (There's actually a quite important one running directly east of the Gulf Stream.) However, from a climatological standpoint they're insignificant. Even if you plan to deal with sea travel or fishing economies, it's easier to just assume that countercurrents are just there than to indicate them on your map. That countercurrents exist doesn't change the main mass of the water flow.

Stuff like the northern Indian Ocean and the arctic currents are why you need to map your largest masses of water first.
Oh, now I see. I didn't even know there was a difference between regular currents and counter-currents. So around the Equator, the important currents just go from east to west?

Qwynegold
10-05-2009, 05:49 PM
OK, how does this look like? At some places it may look odd with red and blue arrows crossing, but I've been told that warm water floats on top of cold water, so it should be okay. And where the big island by the north pole is, a current is branched off, with one branch going north. This current goes under the packed ice (I read on Wikipedia that the ice cap on the North Pole is like at max 30 m thick or something like that, so the current should be able to cross under it). It makes almost a u-turn around the north pole (it's following the clockwise direction of rotation when doing that) and re-emerges near the right edge of the map.

Jeff_Wilson63
10-05-2009, 06:31 PM
Oh, now I see. I didn't even know there was a difference between regular currents and counter-currents. So around the Equator, the important currents just go from east to west?
For purposes of general world mapping, yes. Now, if you were mapping sea travel lanes or fishing resources noting counter-currents would be a good idea. Certain counter-currents can also have a disproportionate affect on local weather, but that can only be discussed individually.

(A side note: I think the Pacific counter-current occurs on so many maps because of the number of Americans who have served on naval vessels in the Pacific. If you're in the middle the Pacific and want to head home, you want to locate that counter-current in order to make the best time. Thus it looms large in people's experience, even if it isn't particularly important on a global scale. I would expect it to be much reduced on Japanese maps.)

Your new map looks really good. The only place that looks odd to me is the sea north of your eastern equatorial continent. At first glance I would expect some circular motion there. Looking a bit more deeply, however, what you have is probably as good at anything else. I really don't have a clue how that would turn out in reality.

Qwynegold
10-06-2009, 12:16 PM
For purposes of general world mapping, yes. Now, if you were mapping sea travel lanes or fishing resources noting counter-currents would be a good idea. Certain counter-currents can also have a disproportionate affect on local weather, but that can only be discussed individually.
Aha, maybe I'll do that later because it's not super-interesting and right now I only need enough to be able to create different biospheres and stuff.


Your new map looks really good. The only place that looks odd to me is the sea north of your eastern equatorial continent. At first glance I would expect some circular motion there. Looking a bit more deeply, however, what you have is probably as good at anything else. I really don't have a clue how that would turn out in reality.
Thanks! I made a little change to the sea you mentioned, and I think it's less fugly now. You can see the changes in the maps I'm posting now.

I made the evaporation and condensation maps now. But I confused those with high- and low-pressure areas. I should just forget about air pressure and concentrate on where water evaporates and condensates, right? As a result, these maps have a little bit of both, so I should do them over. Things that have been affected of me thinking about pressure areas I've marked with a * in the below explanations. But before I do this over I'd like to have your input so I'll know which of my thoughts have been right and which have been wrong.

I've concentrated the blue areas (evaporation or high pressure) over places of the ocean where there are warm currents, because warm water should be likely to evaporate. I've also placed blue areas on land between th 15th and 30th latitudes*, because in those real life weather maps I posted earlier there seemed to be high pressure areas around deserts. I think I've read something in Wikipedia too about deserts making air flow upwards a lot because it's so hot. In the summer I've given deserts on the northern hemisphere more priority over deserts in the southern hemisphere*, because I read on WP that the sun is at zenith on the tropic of cancer during the summer solstice. The situation is reversed during the winter*. But it doesn't make sense with evaporation in the desert, so that's why I'm thinking I should forget about air pressure. In the global scale I've also focused on making a lot of blue zones in the north in summer, and in the south in winter, because the weather is warmer then.

Red areas (condensation or low pressure) I've placed a little bit further away from the blue areas, and on elevated ground, because it's supposed to rain around mountains. Some red areas I've placed in the ocean, like the two in the NW corner of the winter map. I imagine that they get their moisture from the nearby blue areas, but when that moist air travels past a certain point in the north, it rains down because it's too cold there.

For both red and blue areas, I've avoided the equator because the intertropical convergence zone is supposed to be there, and that's supposed to do weird things. According to the WP article (http://en.wikipedia.org/wiki/ITCZ) air is supposed to rise up there. But it also seems like it's supposed to rain a lot there, so I don't understand which is supposed to be true.

The equinoxes I haven't made yet. To me it seems like the spring equinox should be identical to the autumn equinox.:?: Because it's the same temperature/tilt of the axis towards the sun, right? Marking the actual winds I'll save for later when this other stuff has been cleared.

Jeff_Wilson63
10-06-2009, 06:27 PM
I'm afraid you've reached the limits of my knowledge. I don't know what makes for good evaporation and condensation zones. I would say that you have too many zones on your maps, but that's intuition speaking. I don't have anything to back it up.

Keep in mind, however, that these zones move. They move, shrink, grow, break apart, etc., etc. The equinox maps allow you to think about exactly how things move in general.

As regards the equator, as the saturated air rises, it cools, and thus precipitates out. Once that saturated air reaches a certain point, however, it stops rising and thus stops cooling because of altitude. Moving away from the equator it starts cooling again because of latitude, but needs to travel a fair distance before it starts precipitating out again.

Greason Wolfe
10-06-2009, 07:49 PM
Perhaps these links will be useful to your intended goal;

http://www.compulink.co.uk/~morven/worldkit/climate.html (Climate Cookbook)

http://www.blueplanetbiomes.org/climate.htm (World Climate Zones)

http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/main.html (Major Biomes of the World)

http://en.wikipedia.org/wiki/Biome (Wikipedia Biomes page)

GW

zenram
10-06-2009, 08:32 PM
Wow, this is gonna be of use for me too. XD

Qwynegold
10-07-2009, 03:17 PM
http://www.compulink.co.uk/~morven/worldkit/climate.html (Climate Cookbook)
Oh huh, that guy has a section about conworlding too. Thanks, I think I'll manage it now.:)

Qwynegold
10-10-2009, 07:21 PM
I'm in the middle of working with this stuff, but wanted to ask everyone what they think of the climate that I've created so far. I have maps for december, april, june and october.

Blue areas are high pressure and red areas are low pressure. The red line in the middle is the intertropical convergence zone, and the other two are the polar fronts. The blue lines are the subtropical high-pressure zones. The turquoise arrows are moist winds and the yellow ones are dry or medium-dry winds.

I've only worked on the summer and winter northern hemisphere with the winds so far. When it comes to the high and low pressure areas, the spring and fall southern hemisphere is still unfinished.

The last map shows all seasons at once. Some of the pressure zones move around, as can see from lines that gradually go from low to high opacity, and some of them just form and disappear.

Jeff_Wilson63
10-10-2009, 07:49 PM
Looks very nice to me.

Qwynegold
10-11-2009, 12:52 PM
Really? :D Then I'll continue like I've done so far...

Thx for the rep! I repped you too, but it seems like it doesn't count until I have kazillions of post and rep points.

Qwynegold
10-13-2009, 10:55 AM
I've completed the pressure areas and winds and stuff. I've added arrows to the pressure areas to show what direction they are moving towards. D means that it'll dissolve. I think I have a pretty good picture of where the rain is deposited, but I have a few questions.

At places where arrows merge, would that mean that the wind is going faster, because there is more power added? Or would it just mean that the air is more dense there, without the speed being affected? And the opposite for places where arrows split?

There's high pressure area on each pole. Is there only a small quantity of air coming from there, because it's all emanating from a single spot? Or is the air on the poles just super-concentrated, getting thinner as it spreads away from the pole? (I made fewer arrows on the polar areas than elsewhere because one must take the map projection into consideration. When the map is put on a sphere, the arrows at the polar areas will get really close together. I used a lot of arrows around the polar low pressure areas though, just so it would be easy to see how the air is moving around there.)

Does anything special happen when a dry wind and a moist wind merge?

su_liam
10-13-2009, 08:44 PM
When a cold, dry wind from the polar regions meets a hot, moist wind from the tropics a temperate cyclone results, twisting into a large comma-shaped mass of clouds, creating lots of rain and dragging more moist, hot air up from the tropics.