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FarsightX3
06-20-2011, 07:00 PM
You know, one thing that stings me is when the "River Police" come down and knock your rivers. I understand that everyone gets confused of the general structure of a river. But what gets me is, when they harp on "rivers don't flow" north. They usually pick on little curves in the river that the designer made that go northward instead of south. I'd like to point out that the Nile River flows northward. If you look at the Ohio River Map, you can clearly see in some areas that the river flows northward. Will the River Police pick on that natural state?

Example: http://roble.pntic.mec.es/rmac0040/im%E1genes/MississippiRiver.gif

Juggernaut1981
06-20-2011, 07:06 PM
Well to be fair... rivers flow towards the equator... So us "Other Hemisphere" people are used to north-flowing rivers.

It's about "in general" rather than "all and every". In General, rivers flow to the equator. In General, lakes have single outflows and unify (rather than divide). In General, rivers avoid higher-levels-above-sea-level.

So, yeah they'll tell you the rivers should be heading south, because in general that's where they should go. The Nile probably has fair reasons for being the exception (I'd assume there are mountainous or higher-level-above-sea lands to the south)... but it's not just because "I want one that goes north". Unless you have really quite specific reasons for 'not following the general rule'.

RobA
06-20-2011, 07:30 PM
Not sure what either of you are talking about. Rivers flow from high ground to low ground, usually stopping when they hit the sea.

If someone has been criticizing rivers because of their cardinal directionality then we need to have a little discussion. Can't have deputies tromping all over the place willy-nilly.

-Rob A>

Redrobes
06-20-2011, 07:38 PM
I have to admit if there is a rule that said rivers run towards the equator then I had never heard of it. From what I have seen, if you had a circular island then the rivers would run radially out towards the sea - assuming that the middle of the island is the high ground. I would be somewhat confident that all the rivers on the north African coast would be northerly as would those of Norway and the northern realms of Germany and France.

Need links to quoted posts here...

mmmmmpig
06-20-2011, 09:00 PM
heck if you have a conic volcanic structure the drainage pattern is a radial drainage pattern.... but eventually the radial streams will coalesce into one drainage feature. Rivers flow downhill regardless of the direction downhill. The big "no-no" that is consistently viewed with rivers is the branching and eventually reconnecting haphazardly, and that doesn't happen in nature except in river deltas and the braided stream areas in a glacial outwash plain. The second worse violation is rivers flowing past each other into different large bodies of water... there has to be some kind of continental divide and drainage basin setup going on with drainage patterns, since all water flows downhill rivers shouldn't flow past each other without some major elevation change in between them.

Have I forgotten any major river police rules?

Greason Wolfe
06-20-2011, 10:03 PM
Have to agree with Redrobes, here. Rivers flow from high to low regardless of the cardinal direction, as evidenced by the Willamette, John Day, Deschutes and Snake rivers all of which have a mostly northern flow while being in the northern hemisphere. Of particular note would be the John Day river, which is the third longest free-flowing river (no dams) in the conterminous U.S.

Just my two and a half cents.

GW

Talroth
06-20-2011, 10:23 PM
http://en.wikipedia.org/wiki/Continental_divide


Take a look at that page.

The coloured lines on the map show the 'high points', and from there rivers flow in the general direction of the nearest ocean that doesn't cross one of the lines.

Ascension
06-21-2011, 12:22 AM
Obviously he's been chewing on this cud for quite some time and is still angry with Bartmoss for saying that he'd have trouble suspending his disbelief to accept "rivers as veins" and just about everyone here would back Bart up on that. The "offending" post is two months old so it's time for Farsight to drop that and get over it. Not everyone is going to accept your "veins" idea - the physics doesn't support it and the magic excuse stretches our beliefs and knowledge of the subject. Lashing out and saying that other maps with bad rivers don't get policed is flat out wrong and childish as we always point out those things. It's our job to help folks get their rivers correct; whether they accept it or not we point it out. Every map gets seen by us and sometimes one thing might slip through but 99% don't. Most of the time people get mad at us as well so you're not alone there. They also start trying to throw out every unnatural thing they can find on wikipedia to support their claims only to be pointed in the direction of what actually forms that unnatural thing and how their thing is different. Usually this is lakes with multiple outflows (it happens but only for a short time) or lakes having no outflow (these are lakes below sea level so water can't flow uphill to get out) or rivers connecting two oceans (only via man-made canals) or rivers splitting and not reconnecting (not going to happen outside of a delta). Lastly, no one ever said anything about rivers flowing north - you put that into your reply to Bart so your supporting evidence of the Mississippi River does nothing but support an offense that you, yourself, created in your own mind...go back and read the posts. Bottom line, learn to accept criticism like a grown-up...keep the rivers the way you want them but accept the fact that people in the know won't accept them the way that they are. It's your world so do with it as you will. Many folks who know nothing of this matter will accept your rivers without question and will think you to be elite or whatever slang is the new cool. Stomp around, break stuff, and get huffy but then read up on the subject and you'll calm down and maybe someday get to be a deputy. For what it's worth, the rest of the map looks okay (the climates are off but if the rivers are going to use the magic cop-out then so can the climates). I'm sure that I'm offending you as well but I know that I'll get over it...will you?

Mark Oliva
06-21-2011, 04:56 AM
Well to be fair... rivers flow towards the equator... So us "Other Hemisphere" people are used to north-flowing rivers.

It's about "in general" rather than "all and every". In General, rivers flow to the equator. In General, lakes have single outflows and unify (rather than divide). In General, rivers avoid higher-levels-above-sea-level.

Some of this is pure myth. Two of Europe's biggest rivers - the Rhine and Elbe as examples - flow northward, i.e. away from the equator. If rivers avoided higher levels above sea level they wouldn't be able to flow down to the sea (not that all rivers do that). They'd have to flow up to it.

bartmoss
06-21-2011, 06:55 AM
Who?

What?

Me?

I take this badge seriously, Sirs, very seriously indeed, and I'd never unfairly critize a river. Thank you for backing me up.

As for the veins, and addressed at Farsight, well obviously everybody is free to draw maps the way they want, but isn't half the reason to post on these forums to get feedback in the hopes of making all our world designs and maps better?

I certainly hope that if I mess up a river, or bodge some other fundamental in a glaring way, then you guys would step in and call me out on it... and then my v2 of that map will be the better for it.

Juggernaut1981
06-21-2011, 07:20 AM
Some of this is pure myth. Two of Europe's biggest rivers - the Rhine and Elbe as examples - flow northward, i.e. away from the equator. If rivers avoided higher levels above sea level they wouldn't be able to flow down to the sea (not that all rivers do that). They'd have to flow up to it.

Um, that is kind of my point... Rivers LEAVE the areas that are ABOVE sea level and travel TOWARDS Sea Level. And if you look at the geography of Europe, it's a bit hard to flow south with the Alps where they are, consequently those rivers tend to head north.

So Height Above Sea-Level beats centripetal force tendencies for the water to head towards the equator.


*Physics Side-note and the reason for the equator comment...
Any object covered in liquid that is then rotated will have the water move towards the point of greatest radius from the axis of rotation. Catch is that Landform will trump centripetal motion.

bartmoss
06-21-2011, 08:31 AM
*Physics Side-note and the reason for the equator comment...
Any object covered in liquid that is then rotated will have the water move towards the point of greatest radius from the axis of rotation. Catch is that Landform will trump centripetal motion.

That's very theoretical though, in the real world you'll hardly find a planet smooth enough. Indeed, I'd argue that the mere presence of rivers axiomatically means that the sphere can not be smooth enough for such a situation.

And how much does deformity of a planet caused by centrifugal force influence water behavior? I certainly am not good enough at math to figure this one out, but geek enough to want to know the answer! ;)

Steel General
06-21-2011, 08:47 AM
The Niagara river also runs north (and it is north of the equator).

bartmoss
06-21-2011, 09:27 AM
I think we can call "rivers run towards the equator" settled, it is a silly notion. :-)

Gamerprinter
06-21-2011, 12:15 PM
The Vermillion River in Illinois (mouth into the Illinois River is about 15 miles from me) is the only river in North America east of the continental divide that flows north west for its entire length - it too of course is north of the Equator. Topography is rather flat here, however.

NeonKnight
06-21-2011, 12:51 PM
Well, I can certainly see Juggernaught's point. There was an interesting fact from the program. The Earth 'bulges' at the equator from the water. If the earth was to stop spinning, then the oceans would flow to the north and south.

http://channel.nationalgeographic.com/series/aftermath/4464/Overview#tab-Videos/07932_00

bartmoss
06-21-2011, 01:20 PM
Well, I can certainly see Juggernaught's point. There was an interesting fact from the program. The Earth 'bulges' at the equator from the water. If the earth was to stop spinning, then the oceans would flow to the north and south.

Ocean != Rivers, the two are quite different...

RobA
06-21-2011, 03:26 PM
Well, I can certainly see Juggernaught's point. There was an interesting fact from the program. The Earth 'bulges' at the equator from the water. If the earth was to stop spinning, then the oceans would flow to the north and south.

http://channel.nationalgeographic.com/series/aftermath/4464/Overview#tab-Videos/07932_00

I've not seen the show, but if such "speculative fiction" is the current product of the Nat. Geo. Channel then they just lost most of my respect. Producing such sensationalism nonsense isn't really necessary, imoo, when there are so many awesome things in the here and now that could be documented.

-Rob A>

bartmoss
06-21-2011, 03:57 PM
Actually the Earth DOES bulge at the equator, it's not a sphere. (This is not "from the water" but because of the centrifugal force of the planet's rotation.) It's just that the effect is totally negligible for most purposes, and certainly for the flow of rivers.

About that show, well... yeah, sounds like a time waster. Otoh without having actually watched it, who knows, might be a fun thought experiment.

Jaxilon
06-21-2011, 06:06 PM
Hehe, total hi-jack but there's an interesting conversation: is centrifugal force a fictitious force? Arguments abound and I was taught in my physics class that it was Centripetal force that folks should be referring to. In this case I guess it would be the centripetal force of the earth's gravity keeping the water on the planet while it spins instead of allowing it to just fly straight out into space? (actually there is probably the additional force of the earth going around the sun as well but now we are getting even more complex.) I wouldn't be surprised if I'm saying it all wrong either. After all, I'm older, not a physicist, and it's been years since I've tried to explain anything along these lines. I do know that if you go into an older Physics book you won't find centrifugal force in there. I think the newer ones have it so maybe the definition has changed? I dunno.

Anyway, this should probably be in another thread but I know we have at least one real physicist around here. Personally, I gave up arguing over this a long time ago but it always does make me smile when I see the word.

On a side note: I'm not busting bartmoss' chops for using it because it's often used to explain what seems to happen. I just get a kick out of it I guess. English is jacked up in a lot of ways due to it's being a living language and it does change over time. Eventually words become real if enough people use them, even if they started out being used incorrectly. (Ie, "Irregardless" which should just be "regardless" but whatever :) )

Hai-Etlik
06-21-2011, 06:34 PM
They Earth's rotation just distends the geoid, any effect on rivers is balanced out by the land over which they flow being distended too. So they flow down, whatever that is in their location and it can just as easily be away from the equator as toward it.

Juggernaut1981
06-21-2011, 07:11 PM
@Jax: "Centripetal Force" is a fictitious force that makes it easier to explain inertia.
@NeonKnight: If we could stop the rotation of the earth, sea levels to the north and south of the equator would rise. But there is a bulging effect of the underlying landmass by the earth's rotation as well. I suspect that the show has been taken at least a little out of context but could also do with a good researcher.

As I've always said (and if you look further up), height above sea level will be a stronger effect than the rotation of the earth on river-paths.

Hai-Etlik
06-21-2011, 07:38 PM
As I've always said (and if you look further up), height above sea level will be a stronger effect than the rotation of the earth on river-paths.

It isn't so much that that sea level (the geoid) is 'stronger' as that it already incorporates the effect of rotation.

FarsightX3
06-21-2011, 08:36 PM
Obviously he's been chewing on this cud for quite some time and is still angry with Bartmoss for saying that he'd have trouble suspending his disbelief to accept "rivers as veins" and just about everyone here would back Bart up on that. The "offending" post is two months old so it's time for Farsight to drop that and get over it. Not everyone is going to accept your "veins" idea - the physics doesn't support it and the magic excuse stretches our beliefs and knowledge of the subject. Lashing out and saying that other maps with bad rivers don't get policed is flat out wrong and childish as we always point out those things. It's our job to help folks get their rivers correct; whether they accept it or not we point it out. Every map gets seen by us and sometimes one thing might slip through but 99% don't. Most of the time people get mad at us as well so you're not alone there. They also start trying to throw out every unnatural thing they can find on wikipedia to support their claims only to be pointed in the direction of what actually forms that unnatural thing and how their thing is different. Usually this is lakes with multiple outflows (it happens but only for a short time) or lakes having no outflow (these are lakes below sea level so water can't flow uphill to get out) or rivers connecting two oceans (only via man-made canals) or rivers splitting and not reconnecting (not going to happen outside of a delta). Lastly, no one ever said anything about rivers flowing north - you put that into your reply to Bart so your supporting evidence of the Mississippi River does nothing but support an offense that you, yourself, created in your own mind...go back and read the posts. Bottom line, learn to accept criticism like a grown-up...keep the rivers the way you want them but accept the fact that people in the know won't accept them the way that they are. It's your world so do with it as you will. Many folks who know nothing of this matter will accept your rivers without question and will think you to be elite or whatever slang is the new cool. Stomp around, break stuff, and get huffy but then read up on the subject and you'll calm down and maybe someday get to be a deputy. For what it's worth, the rest of the map looks okay (the climates are off but if the rivers are going to use the magic cop-out then so can the climates). I'm sure that I'm offending you as well but I know that I'll get over it...will you?

How did you tie my map to this post? I didn't even mention that. Do you read minds and know peoples intentions? I posted this because I always see someone complain about someones river being badly designed. "Because it flows northward or they don't come from mountains ect. It was just a post I thought I had and would like to share that many people criticize on here without knowledge. This thread has nothing to do with my world. But I really appreciate the personal attack. I am not here to impress anyone or not. I don't care if I am a "river police" on this forum. So next time, be mature and don't assume and insult me. Your post is words without knowledge.

Redrobes
06-21-2011, 09:00 PM
If we can have a little calm... Farsight, can you post a link to the thread / post that said about the rivers running northwards being a problem. If the River Police have said that then I think we should have a look and comment there more than here in this thread. Which map is at the center of this issue ???

LonewandererD
06-21-2011, 11:26 PM
Off Topic: Farsight, you realise by atacking a post by calling it immature and a personal attack is in itself immature and a personal attack. The River Police are here to help, they've called me out plenty of times and I've evolved my practice because of it, they are not law they are advisory you can always choose not to listen. Please, someone call me out if I've overstepped myself, I just felt like it need to be said.

On Topic: From the point of view of person who has a rather limited view of physics I sort of understand and support the idea of water on a rotating globe moving away from axial points and towards the equator but sinse the world is so big and moving at a slower steady rate this effect would be easily trumped by topography and other environmental factors. Though I suppose the idea that rivers don't flow north might have been born form the pseudo-practice that many people seem to draw their maps from a northern hemisphere point of view and naturally draw their rivers going south, I'm guilty of this on many accounts as I find the idea of a river flowing "up" a page or north on a northern hemisphere map as being slightly unnatural. That's just my opinion.

-D-

NeonKnight
06-21-2011, 11:33 PM
Actually the Earth DOES bulge at the equator, it's not a sphere. (This is not "from the water" but because of the centrifugal force of the planet's rotation.) It's just that the effect is totally negligible for most purposes, and certainly for the flow of rivers.

About that show, well... yeah, sounds like a time waster. Otoh without having actually watched it, who knows, might be a fun thought experiment.

That's what the AFTERMATH series is: Fun Thought Experiments. What of the Earth Stopped Spinning (Based on actual Scientific fact, the earth IS Slowing down, this program is a WHAT if instead of millenium it took 6 years instead.)

Other programs in the series, is WHAT IF ALL THE OIL SUDDENLY RAN OUT, and WHAT IF THE SUN SUDDENLY TURNED INTO A RED GIANT, and WHAT IF WE GOT HIT BY A MASSIVE SOLAR FLARE.

The programs are interesting and put things of the BILLIONS OF YEARS into the Span of a few.

Jaxilon
06-22-2011, 12:37 AM
Off topic:

@Jax: "Centripetal Force" is a fictitious force that makes it easier to explain inertia.
Right on, except I think you mean "Centrifugal Force" is the fictitious one used to explain inertia.
Reality is that everything moving wants to travel in a straight line and unless there is some force manipulating it that's what it will do.

On topic:
I'm a fantasy cartographer.

Juggernaut1981
06-22-2011, 02:07 AM
It isn't so much that that sea level (the geoid) is 'stronger' as that it already incorporates the effect of rotation.

In this case, gravity and friction beats the rotational forces (i.e. height above sea level and finding the shortest least-resistant path).

Soak a tennis ball in water, spin it say through a stick and the ends closest to the stick will dry fastest. The rotation will cause the liquid to gather at the point of greatest distance from the stick before it is flicked off and by liquid tension draws the rest of the liquid down to that same place where it will be flicked off. If you covered the ball in all sorts of bumps, then you'd have some 'above sea level' aspect, but the force of the rotation would trump the friction and gravitation of the ball.

RobA
06-22-2011, 04:58 PM
Hehe, total hi-jack but there's an interesting conversation: is centrifugal force a fictitious force?

http://imgs.xkcd.com/comics/centrifugal_force.png

'Nuff said.

-Rob A>

bartmoss
06-22-2011, 05:05 PM
'Nuff said.

-Rob A>

Awesome. Source?

Hawksguard
06-22-2011, 06:52 PM
That's very theoretical though, in the real world you'll hardly find a planet smooth enough. Indeed, I'd argue that the mere presence of rivers axiomatically means that the sphere can not be smooth enough for such a situation.

And how much does deformity of a planet caused by centrifugal force influence water behavior? I certainly am not good enough at math to figure this one out, but geek enough to want to know the answer! ;)

I believe what Juggernaut was describing as it would be applied to planetology is the Coriolos Effect, which basically states water and air will move away from the equator as the planet rotates. In the northern hemisphere, flow is deflected to the right and in the southern hemisphere it will be deflected to the left. Of course, on any planet not entirely covered by water, continents are going to muck around with any type of 'perfect flow' and as a result, you generally have clockwise currents in n.h. and counter-clockwise in the s.h. as part of the heating-cooling cycle of the oceans. Generally. The Coriolis effect however only applies to large objects over large distances, and its effect on a river is going to be all but negligible. Also, the fact that the earth bulges at the equator due to centripetal force isn't going to have any impact on what direction a river flows, it will always follow the path of least resistance from a higher elevation to a lower one.

Jaxilon
06-22-2011, 06:56 PM
@ Roba - ROFLMBO that is hilarious. I love it!

Hawksguard
06-22-2011, 07:38 PM
Awesome. Source?

Looks like xkcd (http://xkcd.com).

RobA
06-22-2011, 10:58 PM
Looks like xkcd (http://xkcd.com).

ding ding! Hawksguard is correct!

I love XKCD.

-Rob A>

Hungry Donner
06-23-2011, 03:22 PM
I'm jumping in a bit late but I can think of far more major rivers that flow north than south, although I don't think there is a bias in that direction either. Most of the largest rivers in Siberia flow North (the Lena, the Ob, the Yenise), as do the MacKenzie and Red rivers of North America, the Tocantins in South America, the Rhine, and the Nile flows North.

Not that there aren't plenty flowing South: Mississippi, Danube, Mekong, Rio de la Plata, Murray, Irrawaddy.

Some are tricky. The Ganges flows more east than south, does it count? If it does the Amazon flows more east than north. The Niger and Congo rivers both have lengthy north-flowing and south-flowing sections.

If you think about it in terms of ocean outflows most rivers going to the Arctic are heading north, most going into the Atlantic and Pacific are heading east or west, and most flowing into the Indian are flowing south. Funny enough most flowing into the Antarctic would also be flowing north if they weren't frozen.

Juggernaut1981
06-23-2011, 03:56 PM
'Nuff said.
-Rob A>

At this point, I surrender and give Rob A the victory based on his XKCD awareness.

I do love XKCD when they're not jumping down the potty-mouth-road-to-victory. :P Check out their radiation chart.