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Nightshade_209
04-03-2014, 10:04 AM
This is a map I have been working on for a post-apocalyptic d&d game and I want to know if making the red-orange area a desert is plausible. I had been looking at pictures of Australia and it kind of looks like that. (the redish brown of the west cost is a reef. though i, probubly going to scale it down.)
brown = Mountains
dark green = Forest
yellow = Grasslands
orange = Deserts
blue = ice
light green = undecided


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I have been trying to use earths wind patterns. My main concern for the rainshadow was earths winds move from east to west so I didn't think those mountains would actually produce a rainshadow effect.

Teal = wetlands/ marsh

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madcowchef
04-03-2014, 11:08 AM
Hmm you'll need more knowledgeable people to weigh in, but its at a good latitude, and you've also put some mountains in front of it for a rain shadow, so it looks very plausible to me at least.

eViLe_eAgLe
04-03-2014, 11:23 AM
Yes, I don't see why not. It looks good to me. The rain shadow depends more on your tradewinds, but i'll assume it's about the same as Earths.
So yes, I don't see why it wouldn't work.

Slylok
04-03-2014, 11:23 AM
I would say its plausible due to the rainshadow from that mountain range to its north and since its on the equator it gets help from equatorial wind belts. im no expert though so hopefully someone else can confirm or deny my reasoning. I like your land shapes.

Pixie
04-03-2014, 01:07 PM
I would say no.

The desert is roughly laid in between the equator and the 20šS parallel and that's the intertropical convergence zone, the good-old-ITCZ. It is basically THE zone for copious daily rain, no seasons and constant humidity.
(check this: ITCZ - An Overview of the Intertropical Convergence Zone or ITCZ (http://geography.about.com/od/climate/a/itcz.htm) or this image:http://upload.wikimedia.org/wikipedia/commons/d/d7/ITCZ_january-july.png).

Deserts are located further south (or north) close to the tropics (and not the equator). That would be around 25-35 degrees, (south in the case of your continent). This is where dry air from the upper layers of the atmosphere sinks (subsides) and heats up in the process (drying even further) and it's called the high pressure belt.
(if you want some easy reading, check this: Brief notes on Sub-tropical high pressure belt (http://www.preservearticles.com/2011111217141/brief-notes-on-sub-tropical-high-pressure-belt.html))
on
I agree with you on the lack of rainshadow effect. Typical winds, in the nothern part of that continent are East-West, warm and full of moist. In fact the general shape of the range would drive them on a long curve southwards and upwards, spreading the rain through the slopes. Depending on the altitude, I think it would be a great place to grow coffee ;).

So, to sum up, here's what I suggest:
- I would keep only the part in lighter orange as desert (give or take),
- establish a tropical forest or monsoon region in the equatorial area south of the main range
- separate the two with a line of savannah

All this is of course, assuming Earth-like behaviour. All this is of course, my feel-free-to-ignore rambling.

Slylok
04-03-2014, 01:44 PM
The desert is roughly laid in between the equator and the 20šS parallel and that's the intertropical convergence zone, the good-old-ITCZ. It is basically THE zone for copious daily rain, no seasons and constant humidity.

Deserts are located further south (or north) close to the tropics (and not the equator). That would be around 25-35 degrees, (south in the case of your continent). This is where dry air from the upper layers of the atmosphere sinks (subsides) and heats up in the process (drying even further) and it's called the high pressure belt.


Thanks for that clarification Pixie! I got that high pressure belt thing backwards :?. Just looking at Africa is a perfect example of it.

Nightshade_209
04-03-2014, 02:24 PM
Thank you for the information. but to clarify, you have it more like the second picture, A forested area by the mountains draining into a wetlands, with a savanna and desert moving east and a dryer climate on the other side of the mountains.

waldronate
04-03-2014, 04:30 PM
To reuse an Erwin Raisz picture:
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jkat718
04-11-2014, 08:11 AM
Kind of off-topic here, sorry, but what program did you use to make those hemisphere maps?

Nightshade_209
04-13-2014, 05:20 PM
you mean the latitude and longitude lines? i used google to find a picture, then put it in photoshop duplicated the layer and moved it next to the other one.

jkat718
04-13-2014, 05:32 PM
So you made the map in Photoshop as two hemispheres, and then added the grid lines afterwards?

Hai-Etlik
04-13-2014, 09:15 PM
The graticules appear to be orthographic which isn't usually done with maps like this as it gives fairly ugly distortion around the edges and is neither equivalent nor conformal. Your features don't show the appropriate distortion for an orthographic projection. The typical projection to use for double hemisphere maps like this is Stereographic.

http://www.cartographersguild.com/mapping-elements/14805-mecator-map-vector-template.html#post155012

Thick lines on a graticule are also a bad idea. Tone them down my making them thinner, not by making them less opaque.

Finally, there's no way to make a map of an entire hemisphere that preserves distances. You shouldn't include a scale bar unless you are either covering a small area where distances are reasonably consistent, OR you are making a special map that only preserves distances to-from a particular point, which you need to make very clear on your map (the one point would need to be at the centre of an equidistant azimuthal projection for instance)