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82

The water in any river draining the sea is infinitely recycle-able (from rain replenishment), whereas the salt from any terrestrial source is not. So salty rivers, if any, won't exist permanently. Saltwater lakes gain their salinity precisely because they have no outlet, so salt just gets concentrated by evaporation. I don't think there are any truly saline ...

31

The already accepted answer is already covering the "real" answer as far as I'm concerned, and while you won't find many (any?) saline rivers in the traditional sense, we do have underwater "rivers" that kiiiiind of but not quite fit the bill. They're not saline rivers as I expect you envision, but I figure they could be an interesting "by the way though" ...

31

Oasis are places where aquifers are connected to the surface. The source of the water in the aquifer however can be hundreds of miles away in areas that do get significant rainfall. The trick is geologic strat have different properties; some allow water to flow easily, others are very water tight, a water accessible layer covered by a water proof layer ...

26

From an Earth Science standpoint, it's meaningless to ask about the "source" of a river in this way. The "source" of a river is the rainfall within its drainage basin, which percolates down into groundwater, and the "river" appears where the land has eroded down below the water table. The Amazon has an enormous drainage basin: and every point in it is ...

25

The Pecos River in Texas, USA may arguably fit the description of a "saltwater river". A point of argument is what is considered to be "saltwater". For comparison, here are some bodies of water and their salinity. 35,000 ppm Pacific and Atlantic Ocean 13,000-23,000 ppm Black Sea 12,500 ppm Caspian Sea 10,000 ppm Baltic Sea Note though, that salinity ...

22

Water from the Caspian sea, with a salinity of 1.2%, is constantly flowing into Garabogazköl, where the water eventually evaporates and leaves the salt behind. Of course, the situation is not indefinitely stable, as the depression is eventually going to be filled with salt. But at the time writing, water is still flowing like a river through the very narrow ...

21

Electricity from waves, from hydro (both run-of-river and storage) and from wind, are all indirect forms of solar power. Electricity from tides is different, and we can deal with that in a separate question. Global tidal electricity generation is not yet at the scale of gigawatts, so it's tiny for now. Winds come about from the sun heating different parts ...

18

Relatively important, depending on the basic principles of the modeling you are interested in, and to what extent you want to get yourself involved in it. In many areas of computational geophysics, e.g. atmospheric, oceanic, hydrological modeling etc., there are modelers, modelers, and modelers. First group of modelers get model output from somebody else, ...

18

Once a dam has been constructed in a river, the natural flow of water will be disrupted. You correctly state that initially there will be a period required for the dam to fill. Until then, little of no water will flow beyond the dam. Dams are created for one or more of three reasons: To supply potable water to a population of humans for domestic or ...

17

The river isn't splitting. The picture shows a number of dendritic drainage channels flowing into a larger river/stream. They are the most common form of topographical draining system. They develop in gently sloping topography and they ... develops in regions underlain by homogeneous material. That is, the subsurface geology has a similar resistance to ...

17

Here in New York City we have a salt "river". It is called the "East River" and it separates part of Long Island (Brooklyn and Queens) from the island of Manhattan and the mainland (The Bronx). Indeed it looks a lot like a salt river: From a hydrology perspective it is not a river tho, it is actually a saltwater estuary.

16

Yes. Nearly global satellite and radar derived rainfall data are hosted by NASA Goddard Space Flight Center, namely: Tropical Rainfall Measurement Mission (TRMM) aboard the TRMM Microwave Imager (TMI), a multi-channel, dual polarized, conical scanning passive microwave radiometer designed to measure rain rates over a wide swath under the TRMM satellite. ...

15

Well, I can only agree that it is indeed amazing and it doesn't get less amazing when some geology, hydrology and geomorphology is added to the the amazement. All precipitation that falls on land must flow back to the oceans somehow, and unless it evaporates it will flow in rivers or as groundwater towards a lower hydrostatic level. Water can not flow ...

15

This is a really complex problem and would require a really detailed explanation about atmospheric circulation, meteorology and hydrology. The short answer to your question is that water is going somewhere else. If you look at the studies about moisture recycling, among the others van der Ent et al 2014 or 2010, you can see that the precipitation that ...

14

You're making a mistake, at least for the second case: In the second case, the water ends up as rain, presumably within a few hundred kilometers of the evaporation point. You cannot model a dry region (or indeed any region on earth) as a closed system for hydrological purposes. When water evaporates in a dry climate, it transports much farther than a ...

14

You're correct that simply putting a dam in place, once its lake is filled, doesn't change the average flow downstream by more than a few percent (those few percent can be lost to increased evaporation). However, Many dam systems are used to abstract water from the river for irrigation and other uses, sometimes on a very large scale. This does reduce the ...

14

There are two types of oases: natural and human made. Natural oases form when springs, created when underground aquifers allow fresh water to pool or flow on the ground surface of deserts, creating a fertile region. A human made oasis occurs when humans create fertile region in a dry or arid region, such as a desert. The supply of water in human made oases ...

13

I'm under the impression you're not asking why a meandering river will keep meandering, but why even a straight river will start to meander in the first place. The first is indeed by erosion of the outside of the bends, and deposition on the inside of the bend, which is fairly easy to understand. On the origin of meanders, this is a more complicated matter. ...

13

Meanders amplify themselves--the stream tends to erode on the outside of the meander (forming a cut bank) and deposit sediment on the inside (forming a point bar). Eventually, the meander will propagate so far from the stream's mean path that the stream cuts across it. Eventually, the old meander will turn into an oxbow lake and fill in. As to why it ...

13

If you are looking for a dataset going back a bit further, but still sticking to satellite and radar data, GPCP (Global Precipitation Climatology Project) goes back to 1979. The limitation of certain TRMM datasets, in addition to the relatively short length of the project, is that they only cover the tropics and so you lack data in the mid-latitudes and ...

13

I live near a river named Salz, flowing both warm and salty on the north slope of the Pyrenees south of Carcassonne. In historical times it was boiled dry for salt. See Les Sources de Salz

12

The groundwater table depends on a lot of properties. These include precipitation rates, permeability/transmissivity of the subsurface and regional groundwater flow. There are two different regimes that are distinguished: one with a topography-controlled watertable and the other with a recharge-controlled watertable. A topography-controlled watertable ...

11

Fossil groundwater is water that has been trapped below the surface for several thousands of years. It is considered non-renewable as natural recharge on human timescales is practically zero. This is because the permeability/transmissivity of the overlying strata is very low. However, on geological timescales the aquifer will recharge as pumping the water ...

11

Given the subject matter of the paper, I'd assume that it stands for carbon, and the whole expression refers to milligrams of carbon (or organic carbon) per litre of lake water.

11

Here are a few, completely random advices I wished someone would have given me before I started to study geology. I'm aware of that this is over simplified, but I believe that it's good to start easy, gain interest and later, with experience, understand that you have been wrong. A good book to start with: Earth: Portrait of a Planet by Stephen Marshak. It ...

11

I will attempt at rephrasing your interesting question after these considerations: At the continental scale, flowing water has no significant inertia, so water flows following the maximum slope. A river is just a path along the continent that follows the maximum local slope at any of the places it passes through. What amazes you (let me interpret) is that ...

11

There are salt water rivers in different places of the world where ground water flows in contact with salt layers. There is a river in Catalonia named Ribera Salada (meaning salty river in Catalan). My translation from Catalan Wikipedia: It gets its name because one of its originating currents - Fred river - comes from sources in Triassic lands with a ...

11

I guess there are multiple names, but I know it as the river's "long profile", and it is used in academic papers (one example here and a search in google scholar here). But you can find similar diagrams under names like the river's height profile, longitudinal profile, longitudinal map or geographic profile. These last two are the ones used in an Australian ...

10

So let's get through some definitions. I will not discuss the derivations of this, but you can look this up, if you want to in the source I provided. We find ourselves in a porous medium, so we will have always some volume filling factor $\Theta$ of water in rock. (copyright K. Roth, Heidelberg University) Then we can start with the hydraulic ...

10

When the flow of water in a river accelerates, it can pick up more sediment from the river bed and transport it downstream. Alternatively, when the flow slows down, the transport capacity drops and the sediments suspended are deposited on the river bed. When a river goes into a lake, it transitions from the fast-flowing regime in the river to a very slow ...

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