# Tag Info

34

When dissolved in water, salt breaks up into sodium and chlorine ions, which combine with water molecules so they cannot easily sink. However, there is a tendency for streams of fresh water to float on salt water and rise to the top. This caused problems for British submarines in the Dardanelles Straits during WW1. Moving from almost fresh water to the ...

22

Why does the salt in the oceans not sink to the bottom? Because there isn't any "salt", per se, in the ocean. Salt, as the compound sodium chloride (NaCl) does not exist as a solid in the ocean. It is dissolved into sodium and chloride ions (charged atoms) that exist within the ocean as a homogenous phase (that is, a "thing"). That said, water with sodium ...

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 ...

9

I'm ignorant of all the organic and inorganic chemical reactions that can destroy or create water, and the factors controlling them. But I can give a shot to the part of the question related to volcanoes and the water stored on Earth's interior: The most abundant gas in volcanic eruptions is water, corresponding to more than the 80% of emitted gases in ...

9

We pump it out. Open and closed pit mines usually have pumping installations to get the water out. Look up Mine dewatering on Wikipedia. There have also been numerous accidents in the past where mines were flooded (YouTube: Turkey mining accident: 18 workers trapped after underground water floods mine), and when left alone many abandoned mines will fill up ...

7

I'm a regular from the Physics Stack Exchange reporting for duty. Why this is a serious question This is a bigger question than you might be giving it credit for. The question is ultimately similar to asking why all the air molecules in the atmosphere do not fall to the floor. Your question comes from a very solid principle in physics which could be called ...

6

It is blue. But white light needs to cross a long distance through the water to actually get the blue tint. This related question explains it for ice, but for water it is pretty much the same story. This article, mentioned by @JeopardyTempest in the comments of the answer to the above question, tackles the case of the oceans. There it says: The ocean ...

5

It is not actual water what is lost to space, because in the high atmosphere water usually dissociate into other molecules or ions. The oxygen ion outflow is frequently assumed to be a proxy for the loss of water from the planetary atmosphere. In terms of global outflow rates for the Earth the rate varies from $10^{25}$ to $10^{26} s^{-1}$, depending on ...

5

Turbulence, because seawater is, almost, always on the move saltier water is mixed with fresher by wave action and, to a lesser extent in surface waters, by Brownian motion. In Fjordland the annual rainfall is so high (up to 8000mm) that there is a permanent freshwater layer several metres thick that you can drink from sitting over the salt water from the ...

5

Saltier water has higher mass density, so the gravitational energy can be lowered that way. The concentration differences go up until the free-energy of creating that big a concentration difference balances the gravitational energy change. Department of Physics, University of Illinois at Urbana-Champaign Making some simplifying assumptions, they find: ...

4

Interesting question. As long as plate tectonics persists, then, as @Arkenstein mentions, mountain building and ocean basin formation will create enough topographical variety to ensure that land exists. Moreover, as long as there is a distinction between continental and oceanic lithosphere, we will have continents. But this will not last forever. At some ...

4

I would call that about a force 3. But be aware that one of the problems near shore is that the shoreline, buildings, and topography have a large effect on the local winds - both direction and speed. Also fetch makes a difference - waves don't have enough time/space to build to their full size without sufficient fetch. Not the case in your video but it is ...

4

There is a limit to how much of a given salt can be dissolved into water, this is known as it's solubility and it's dynamic based upon how much of any particular ion is already present. Once concentrations exceed the local solubility of a given compound precipitation occurs, this can be seen in the modern Mediterranean basin with the precipitation of calcium ...

4

The orange lakes are most likely tailing dams, also known as tailings storing facilities given that they located near an open pit iron ore mine. Once iron ore has been mined it is usually sent to a processing plant to increase the grade (amount) of iron in the product the mine exports. It does this by removing as much waste material as possible. Sometimes ...

3

Phosphorus & phosphates are a key component of agricultural and garden fertilizers. Most plants need nitrogen (N), phosphorus (P) and potassium (K). They are generally combined into one product called NPK fertilizers. Nitrogen is needed for leaf growth. Phosphorus is needed for roots, flowers, seeds and fruit and potassium is needed for stem growth and ...

3

Reactions that can produce or destroy water: ${\displaystyle {\hbox{H}}_{2}{\hbox{CO}}_{3}\to {\hbox{H}}_{2}{\hbox{O}}+{\hbox{C}}{\hbox{O}}_{2}}$ (and there is plenty of ${\hbox{H}}_{2}{\hbox{CO}}_{3}$ (carbonic acid) in the sea water). ${\displaystyle {\hbox{HCl}}+{\hbox{NaOH}}\to {\hbox{H}}_{2}{\hbox{O}}+{\hbox{NaCl}}}$ Combustion: \${\displaystyle {\...

3

The question is slightly confused, because reducing the temperature of the oceans, in a direct sense, doesn't require energy - it releases it. The amount that is released is simply related to the mass and specific heat capacity of seawater, as you suggest. The missing question, though, is why the ocean is cooling. For it to happen naturally and simply ...

3

Hydrology major here, for whatever that's worth :) Some possibilities from my readings/internships: First I'd check the gage you're using for stage--if it's moved in the last 8 years, the stage may need to be correlated to what it would be at the former site. If it hasn't, it's more likely something changed in your stretch of channel. If the channel has ...

3

Some time ago I posted this answer about how rainbows are formed, and the Wikipedia link Trond Hansen posted mentions droplet size relative to the wavelength of light. For a rainbow to form, the droplet size has to be large enough, relative to the color with the longest wavelength of visible light, for it to be refracted before reflecting off the backside ...

3

The water year does vary depending on the region, for example in Australia the water year begins on July 1. I am not sure about other regions, I believe the October 1st water year is quite standard across the northern hemisphere although may shift as you go far north to polar and more arid climates. I would recommend searching for similar links to the one ...

3

You need to calculate the change in the moment of inertia of the Earth and use conservation of angular momentum (the rotation period is proportional to the moment of inertia). Most of the water will ultimately come from the oceans, effectively removing a thin layer of water. Jerry Mitrovica discusses this effect (in reverse) in a Nautilus interview: Is ...

2

Most of the world's land is more than one hundred kilometers from the nearest ocean, yet still gets rain. There are portions of the Rockies that are about a thousand kilometers from the nearest ocean. And since clearly a large portion of the precipitation that lands in the Rockies flows to the ocean, there must be some mechanism taking water back to the ...

2

The problem about rain water catchment is, that it prevents ground water from being formed, thus depleting these ressources and making them unavailable during droughts. Plus, ground water tends to be cleaner than rain water as far as I know - provided there's no fracking or subterranean atomic waste storage around.

2

Rain water is still one of the most cleanest water sources available. There may be some ancient underground aquifers that have clean uncontaminated water. One issue with rain water is that atmospheric moisture - part of the water cycle - needs to condense on aerosols in the atmosphere before it can develop into rain. With the amount of pollution humans are ...

2

This is due to the presence of iron sulfide in the water. The iron sulfide oxidizes and goes into solution. Ferrous iron oxidizes to ferric iron. Depending on the water chemistry, this commonly precipitates out as orange-coloured iron oxyhydroxide, but that does not seem to be occuring in your case, otherwise you would see it. When it does happen, the pH of ...

2

Note that you may have a bit of a misconception: the land heights/ocean depths, even what % of Earth is ocean, aren't too important because when land erodes, it doesn't fill in much of the depths, but instead raises the ocean bottom AND ocean top by similar amounts - the amount of water on Earth still needs somewhere to go! It still just tends to sit on top ...

2

We know that terrestrial hydrogen reaches space because ultraviolet images reveal a halo of hydrogen atoms surrounding the Earth (Fig. 2). Some of these atoms are escaping while the rest are trapped. The temperature at Earth’s exobase is typically around 1000 K, although it varies as the Sun’s ultraviolet output cycles up and down every 11 years or ...

2

I think everyone would agree that distilled water is clean fresh water, but it wouldn't be practical to supply a large population with a water supply made up entirely of distilled water. Good water desalination devices using semi-permeable membranes have been invented and are used in some drought stricken countries. They can filter out things as small as ...

2

It's been proposed. Not for California, but for the Sahara, and the Empty Quarter in Arabia. The notion is that you are creating an interior salt sea -- the equivalent of Great Salt lake. Evaporation from that sea modifieds the local climate. You have to move a LOT of water. Done right,you can process the resulting salt for other products. Bromine, ...

Only top voted, non community-wiki answers of a minimum length are eligible