Home « Forum « Author Hangout

Forum: Author Hangout

Oceanautic Upwellings

Crumbly Writer

Need some technical details for a story.

The scene revolves around a deep water upwelling of water, often helped by underwater currents in deep-sea trenches, but more often accounted for by temperature variants (similar to air currents allowing birds to hover in place). Assuming there is a substantial temperature difference, what would be the effect at the surface, seeing as how the oceans are warmer at the surface and extremely cold deep underwater. Would the water at the surface be freezing, or warmer than usual (assuming there are no volcanic vents involved).

I'm assuming the temperatures are different deep underwater, but the effect is negated as the water rises. In which case, the water continues rising because it's being pushed by the uprising water beneath it.

Any oceanographers among us?

REP

@Crumbly Writer

Any oceanographers among us?


Not me. I recall there being thermoclines in the ocean that submarines can use to prevent detection, so the the water temperature is not a uniformly increasing gradient from ocean floor to surface.

It seems as though that effect at the surface would depend on several variables.

If the upwelling is deep enough the rising water might disperse or cool and settle without ever reaching the surface.

Alternatively, if the upwelling extends upward over time or is strong enough, it seems as if an observer might see sediment and debris rising a one point and flowing outward before it sinks or disperses. Surface winds could affect the visibility of this surface disturbance.

Crumbly Writer
Updated:

The scene I'm envisioning is a location where whales, dolphins and seals (all known to dive to incredible distances underwater), breach the surface where most surface debris is swept aside by the uprising currents (the particulate matter often dissipates (drifts off) on the way up). However, I need to know whether the water at the surface would be warmer or colder than normal.

The assumption is, the animals all 'ride the currents' to ease their journeys.

Replies:   REP
REP

@Crumbly Writer

Logic would say warmer than usual. If the upwelling were to cool off to the point it was colder than the surrounding water, it would stop rising and settle.

Replies:   Dominions Son
Dominions Son

@Crumbly Writer

I'm not, but I can give you a few hints.

The top few meters of water are warmer than what is below them because they are heated by incoming solar radiation.

Beyond that the layering of water in the oceans has as much to do with variations in salinity as temperature. cold fresh water (ice melt, rain water) is less dense then and will float on warm salty water.

There are permanent circulatory currents in the oceans that overturn the waters every few thousand years, circulating water between the equators and the poles. I forget off the top of my head if the up-welling is at the equator or the poles. Google thermohaline circulation.

Here is some information on ocean temperature profiles with links to more info.

More localized upwelling of deep water would most likely result from geothermal activity on the ocean floor.

Replies:   Crumbly Writer
Crumbly Writer

@Dominions Son

There are permanent circulatory currents in the oceans that overturn the waters every few thousand years, circulating water between the equators and the poles. I forget off the top of my head if the up-welling is at the equator or the poles. Google thermohaline circulation.

My understanding (and I could easily be mistaken) is that these 'thermal transfers' don't occur at specific boundries, but at specific locations (i.e. random locations based on the undersea landscapes which funnel undersea currents toward the surface, often controlled and influenced by temperature variations (causing the undersea currents to rise instead of continuing as it normally would along the bottom).

But I'll read up on your links for more info.

Dominions Son

@REP

Logic would say warmer than usual. If the upwelling were to cool off to the point it was colder than the surrounding water, it would stop rising and settle.


Rising and settling of water in the column is driven by density. Temperature affects density, but so does salinity. Cold but less salty water would also rise until the salinity equalized with the surrounding water.

Crumbly Writer

Drat. According to your link, most of the 'uprising water' from the deep sea flows, only rise where the Atlantic meets the Pacific and Indian oceans (I need it to occur mid-Atlantic, between NY and England).

I seem to recall (from somewhere) that there are a couple isolated 'upwelling points' around Iceland/Greenland where the deeper cold water rises to the surface, warming as it rises. However, I'm now questioning those assumptions (as I probably heard it as a child).

Replies:   Dominions Son
Dominions Son

@Crumbly Writer

(I need it to occur mid-Atlantic, between NY and England


Easy solution, rather than relying on the long term circulations, create an underwater volcano or thermal vents to create a temporary and/or localized thermal upwelling.

There are a few known submarine volcanoes in the mid Atlantic, If one were to erupt, that would cause a localized upwelling.

Replies:   Crumbly Writer
Crumbly Writer

@Dominions Son

Easy solution, rather than relying on the long term circulations, create an underwater volcano or thermal vents to create a temporary and/or localized thermal upwelling.

There are a few known submarine volcanoes in the mid Atlantic, If one were to erupt, that would cause a localized upwelling.

Nah, it needs to be a site dolphins and whales frequent. If there's volcanic activity nearby, they'd avoid the scene like the plague, as it would disrupt the krill they feed on. (Though, realistically, I suspect they only feed near the surface where the plankton is plentiful, though I'm unsure why they dive so deep in the first place.)

I may need to drop the entire scene, as it no longer seem plausible.

Replies:   Dominions Son  paliden  REP
Dominions Son

@Crumbly Writer

Nah, it needs to be a site dolphins and whales frequent.


In that case, you can likely do without the upwelling.

There is plenty of whale activity in the mid atlantic

paliden

@Crumbly Writer

I suspect they only feed near the surface where the plankton is plentiful


The diet of whales depends on their species; it can range from microscopic plankton to large marine mammals.
ref-https://www.defenders.org/whales/basic-facts

unsure why they dive so deep in the first place

Which whale is the deepest diver?

A Cuvier's beaked whale has been recorded to dive to a depth of 3km for over 2 hours.

Sperm whales are also champion divers. Adults can stay underwater for almost two hours and dive to depths of 2,000 metres or more. They eat squid, which can live very deep in the ocean, so sperm whales have to dive down into the deepest parts of the sea to catch them.
ref-http://us.whales.org/whales-and-dolphins/facts-about-whales

REP

@Crumbly Writer

I'm unsure why they dive so deep in the first place.)


You might as well as a mountain climber why he climbs mountains.

Ernest Bywater

@Crumbly Writer

Having been near a blow hole, and also a current uplift, the water in both comes from deeper down and is actually colder than the surrounding water when it's still in the up-swelling and just after it reaches the surface. It then spreads and reaches the same temperature as the water around it, but the up-swelling continues to be cold due to the constant flow of cold water from much deeper down.

The two cases of water up-swelling I know of were due to a strong current flowing in to meet some under water rocks near the coast, the rocks deflected a part of the current upward while the rest flowed on by. The deflected water flowed upward with the pressure of the current, and maintained it's cold deeper water temperature until it hit the surface in a sort of dome, and spread out from it into the surrounding water. The rocks that deflected it upwards showed evidence of being worn down by the constant flow of the water, too.

BTW Thermoclines are usually depicted as the interface where two very different water temperatures meet, and thus the sharp temperature gradient creates a reflective barrier.

StarFleet Carl

@Crumbly Writer

To expand upon what Ernest said, imagine the typical mushroom cloud, only with cold water at the base. It's going to be very cold at the bottom, warming slightly as it rises, and then roiling together to create the 'cloud' zone, where the warmer surface water is mixing with the colder water coming from below.

In a confined space - a rock quarry, for example - you're going to find sharp thermoclines, typically two or three, depending upon how deep you go. In open and flowing water, you'll hit the first thermocline, and then it may take a while to hit the second, just due to currents.

From what it sounds like you're describing, you COULD get away with a simple volcanic vent. Those happen all the time, and it could be warming the water enough around it to cause an uptick in the plankton growth, enough for the plankton feeders to congregate. Those are called hydrothermal vents.

http://animals.mom.me/list-animals-live-near-thermal-vents-2973.html

sharkjcw

How about around the gulf stream? It reaches into the north Atlantic.

Replies:   Crumbly Writer
Crumbly Writer

@sharkjcw

How about around the gulf stream? It reaches into the north Atlantic.

No, I was looking for a place where whales would surface, after diving as deep as possible, and where the surface debris is swept clear by the upwelling water. I may keep the premise, maintaining it's a small upward swell of the deeper undersea current (meaning it would be cold, which is what I'd originally imagined), even though it's not scientifically logical. However, it makes a nice intro to the story. Besides, the Gulf stream shadows the eastern U.S. coast, whereas I wanted it closer to the English coast.

In short, I need to rethink my premise, even if I do keep the chapter segment.

On the other hand, I could posit a new thermal vent, created by an asteroid impact which triggered and underwater thermal vent which would achieve the same thing. I'll have to consider which I want, though whales would be less likely to swim very far into such an environment. :(

Ross at Play

@Crumbly Writer

Besides, the Gulf stream shadows the eastern U.S. coast, whereas I wanted it closer to the English coast.

The Gulf Stream DOES reach the English coast. If it did not, London and Paris would be as uninhabitable as parts of Canada on the same latitude.

Dominions Son

@Crumbly Writer

I want, though whales would be less likely to swim very far into such an environment. :(


You'd be surprised, the zone which would be uninhabitable to conventional life forms is smaller than you might think. Scientists have discovered chemosythetic organisms that derive energy from chemical reactions with in-organic chemicals in the vents that can survive even at the very opening of the vent.

As a result of those organisms, the rising column of warm water (which cools fairly rapidly) in the cold depths of the ocean is very rich in nutrients for more familiar forms of life.

Unless the vent was in relatively shallow water (under 2000 meters) most whales likely wouldn't be bothered that much by it.

They might have to stay out of the central column of the thermal vent at depth, but the filter feeding whales would likely find a superabundance of food surrounding it.

The asteroid impact is probably not necessary there are known natural vents along the mid-Atlantic ridge. There is more information on the vents and a link to a global map of known active vents here.

Crumbly Writer

Thanks, D.S. the links are appreciated.

The asteroid impact is probably not necessary there are known natural vents along the mid-Atlantic ridge.

Spoiler Warning: I went the asteroid impact route because it fits the story, not because I thought it was necessary to include thermal venting in the story. In fact, it would fold perfectly into the story. (Now, does anyone not know what story I'm talking about?) :)

awnlee jawking

@Crumbly Writer

Stoopid question - shouldn't that be Oceanic Upwellings? Oceanaut makes me think of Astronaut and Cosmonaut.

AJ

Replies:   Crumbly Writer
Crumbly Writer

@awnlee jawking

Stoopid question

There are no stoopid questions, just threads that have run their course, leaving nothing but weak puns and political lamentations.

But yeah, it Shoold.

awnlee jawking

@Crumbly Writer

nothing but weak puns and political lamentations


You know me too well!

AJ

Dominions Son

@Crumbly Writer

political lamentations.


I've heard of tar & feathers, but I never considered using them to glue one politician to another before. :)

Replies:   REP
REP

@Dominions Son

using them to glue one politician to another before. :)


Well, we could try it with Hillary and Donald and then drop them in CW's deep water upwelling to see what happens.

Replies:   Ross at Play
Ross at Play

@REP

Well, we could try it with Hillary and Donald and then drop them in CW's deep water upwelling to see what happens.

Sadly ... hot air rises.

Replies:   Crumbly Writer
Crumbly Writer

@Ross at Play

Sadly ... hot air rises.

Maybe, but at least we could try them both for witchcraft, just on the odd chance the charges might stick (i.e. they might survive their dunking, proving they're guilty, since evil supposedly floats). :)

Replies:   Ross at Play
Ross at Play

@Crumbly Writer

Seriously, Americans do this all the time, and it drives British and Australians crazy.
This is funny.

Maybe, but at least we could try them both for witchcraft, just on the odd chance the charges might stick

This completely spoils the joke by explaining it.

(i.e. they might survive their dunking, proving they're guilty, since evil supposedly floats). :)

richardshagrin

@Crumbly Writer

The scene revolves around a deep water upwelling of water, often helped by underwater currents


In other words, its about current events.

Replies:   Ernest Bywater
Ernest Bywater

@richardshagrin

In other words, its about current events.


Yes, and you should just go with the flow.

Replies:   Dominions Son
Dominions Son

@Ernest Bywater

Yes, and you should just go with the flow


Doesn't she sell insurance?

Replies:   Ernest Bywater
Ernest Bywater

@Dominions Son


Doesn't she sell insurance?


Yes, to sea shells on the sea shore

Back to Top