Sea Floor - Surface - Satellite - Shore 41
slambo writes: "Wondering how research is conducted on the ocean floor? One of the methods, as described by Woods Hole Oceanographic Institution (WHOI) is to put sensors on the sea floor that transmit the data through a cable to a buoy that then bounces the data through a satellite to the land station. They have an overview on their website. The main advantage of this setup is near real-time monitoring of activities on the sea floor."
Re:Don't waste nuclear waste! (Score:2)
oceanic challenges (Score:1)
observational oceanographers (of which I count myself one-
got my PhD from WHOI and MIT in 1999) have to put up with,
just to give people an idea of the odd and difficult things
oceanographers have to put up with:
1. The aforementioned pressure issue. earth's sfc ->space = -1atm.
earth's sfc -> Ocean depths \approx 500 atm. Electronics packages
are commonly flooded with a non-conducting, incompressible (relative to air)
oil so that their containers don't implode. Makes working on
them a real challenge.
2. It transmits electromagnetic energy very poorly. For the same reason
it is difficult to communicate with submarines, it is difficult to
communicate with instrumentation in the ocean. That's why projects
like the Martha's Vineyard deployment, Rutger's LEO-15, etc are
so cool- they bother to actually hard-wire lots of stuff in so that
you can get the data back in real time.
3. It's very conductive and corrosive. Not only a problem for
instruments you place in the water, which have to be superbly grounded,
but for any laptop/etc you have on board. Everything is suffused with
salt spray by the end of a cruise.
4. It's a physically difficult medium to work with. More oceanographers
than not are susceptible to seasickness (myself included). Moored
instruments (instruments held in place with an anchor to collect time series)
have to be very well moored if you want them to be there when you get back.
5. Some of the signals we're interested in are very small. Standard
instrument errors for temperature measurements, for instance, tend
to be on the order of 1mC. This takes very sensitive electronics and
frequent calibration.
6. It's big. The ocean is a big place, relative to the speed a research
vessel can move. For some (not me- I'm a coastal oceanographer) the
first two weeks of a cruise might consist of just getting there.
Doesn't sound like much, but then figure you're paying ~$35k/day for the
boat...
Aside from these, let me just say that I'm pleased to see oceaographic
topics pop up on
some really cool engineering and scientific challenges. Although
the WHOI deployment will be used to answer some interesting scientific
issues, it's main role as I see it right now is as an engineering testbed.
There are tons of things to work out before we can do this at any
sort of larger scale.
Alternative Techniques - Project Neptune (Score:2)
I worked for WHOI for a year doing onboard science support (net admin, programmer, technician, whatever it took, etc.). There is a heavy use of linux by oceanography folks. The WHOI and UW ships all use linux mostly, though Scripps uses a lot of Solaris.
Makes so much sense (Score:2)
Dropping down at intervals in Alvin (or whatever other submersible, crewed or not) is pricey, and you can only be down for a little while every once in a blue moon. Only a few vent sites have been visited regularly enough to get a sense of how things change there. Put down remote sensors with a steady signal back, and you can maybe try to figure out how tube worms and shrimp and so on colonize new areas. This is a totally different basis for life down there; those animals live on chemosynthesis at the base of their food chain, not photosynthesis, and we know almost nothing about them. What we need is to do what old time naturalists did -- watch a while to get the basics down.
Plus, our clumsy sub's scared off anything mobile by the time it staggers noisily into view. Here's hoping architeuthis dux slips into view of one of these remotes at some point.
As for dumping nuclear waste down there -- you think putting nuclear waste directly into a fault makes sense? Even if you didn't have to lower it down through pressures that'd crack all but the most specialized, titanium sub, that'd be idiotic. (Here's hoping that giant squid mutates like in an old movie and comes for you.)
The End?...
More damned nosy bums! (Score:1)
(Signed)
Captain Nemo
Davy Jones
Ariel
Admiral Nelson
Patrick Duffy
Re:We're going to need deep sea technology (Score:1)
http://www.jul.com/
Re:oceanic challenges (Score:1)
1) Going out to sea is like being in prison, albeit with the extra benefit of the threat of drowning.
2) Try eating chicken ala king when the ship is rocking and rolling, and everybody is getting seasick. Actually, it is just difficult to stare a plate of chicken ala king under those conditions.
3) There is something special about taking a piss off the back deck while in the middle of the ocean.
4) I love the smell of diesel fumes in the morning.
5) You quickly find out who doesn't like to take a bath.
6) It is not good to hear your co-worker say, "Shit! That's a freakin big wave!" while working on the back deck of a boat in the cold North Atlantic.
7) It is not considered polite to chew tobacco and spit while standing next to a person who is seasick.
8) It is fun to have naive gullible newbies on a cruise. Here, hold this pole and snag the mail buoy as it floats by.
Re:Elevator Goin Down (Score:2)
Water is more turbulent than a vacuum or an atmosphere. So it would be more stressfull on mechanical items
Plus there is the old maxim about the ocean. Put something in the ocean, and either something will grow on it, something will try to eat it, or it will corrode.
This provides for a number of interesting engineering problems.
the simplest solution is what is used right now. You drop the submarine to the bottom, and release ballast to float to the top.
Re:Hmm... (Score:1)
Re:Save The Whales! (Score:1)
Also note that sound intensity levels drop off at a rate of 20 log10(r) where r is in meters; this is for spherical spreading loss. Cylindrical spreading loss drops off as 10 log10(r). As a side note, the source level (underwater) of a compact/point source of P watts is given by 171 dB + 10 log10(P).
Finally, the loudest underwater noise source is Mother Nature (earthquakes, underwater volcanoes, and to a lesser degree, lightning strikes).
Re:We're going to need deep sea technology (Score:1)
I disagree.
I also think research of our oceans is important. But the destiny of mankind is space, the sooner the better. The reason I think that is that in the end life on Earth will be destroyed or made impossible, by nature or by humans (impact by large object, nuclear war, etc).
If there are multiple Earths (with ocean research etc), mankind will likely exist much longer.
We have to get out of our planetary cradle.
V.
Another option (Score:1)
Back on subduction zones, didn't they use this in David Brin's Uplift series for all waste? The idea was that when a civilization left a planet, all trace of their existence would be destroyed by natural geological processes (not leaving any mysterious artefacts for native sentients to find).
Off topic (Score:1)
__
Re:Save The Whales! (Score:1)
Finally, the loudest underwater noise source is Mother Nature (earthquakes, underwater volcanoes, and to a lesser degree, lightning strikes).
It bears noting that these are basically "one time events", not a continuous 24/7 stream of sound. It has been suggested that Navy tests of these devices have been responsible for mass whale beachings recently in Hawaii and other areas.
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Elevator Goin Down (Score:1)
humor for the clinically insane [mikegallay.com]
recycle old military/commercial cables (Score:2)
data works and obselete telephone cables.
They have a floating island (Score:1)
Re:Yeah, because so much stuff happens there... (Score:2)
"Yup, it's wet today again"...
75% or earth poorly monitored (Score:2)
may not be as mouch 20th century global warming
as thought. Human settlements distort land-based
measurements. Subsea measurements are rather sparse.
It would be nice to know better.
Don't waste nuclear waste! (Score:2)
Now, I'm not taling about low level crap lie booties and overalls, but the higher level srtuff.
Now, some people may argue that breeder reactors can cause increased nuclear proliferation, but that's not necessarily a bad thing. Just like the second amendment postulated, as more states are armed with nuclear weapons, wars break out less and less, and stability increases. Smart guys, those founding fathers.
Cthulhu Ftaghn! (Score:2)
In his house at R'lyeh dead Cthulhu waits dreaming.
Ia, Ia, Cthulhu Ftaghn!
NOAA (Score:1)
Re:Subset of returned data (Score:2)
The data is very old or there is a software problem
> Humidity: %100 +/- 0%
The probe is in water
> Light: 0 Lumens +/- 0 Lumens
It is dark
> Pressure: OVERFLOW
The pressure is too high to read
> Temperature: 0.56 C
It is cold, close to freezing
informative huh? surprising deep sea conditions!
Personal experience (Score:3)
We have monitoring! (Score:2)
Eventually someone in the trans Atlantic cable business noticed cables breaking at regular intervals, based on the distance apart they were.
It turns out the turbidity currents were breaking the cables. We knew where the cables were, and exactly when they broke! So that's how we figured out how fast these avalanches are.
they've got a Y2K bug (Score:1)
Also, it's wet, dark, under great pressure, and barely above freezing. You sure you didn't pick up a drowning weather balloon instead? 8-)
look up the word analogy (Score:1)
Re:We're going to need deep sea technology (Score:1)
Just a pedantry note to an othewise well written comment: Decompression requirements are a function of time and depth, not just depth. Enuough time at *any* depth will eventualy put you into an obligated decompression mode, and one can be at 3ATM guage and not obligate for decompression. For air, I think US Navy tables give you ~10 minutes before you are obligated, while recreational tables will be more conservative.
$0.02 worth!
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Re:Like dumping nuclear waste into subduction zone (Score:2)
Also what difference does it make? Oceanic plates subduct at a rate of a few cm's per year. They dont melt for hundereds of km's under the continent they are subducting under, or millions of years. Some theorys about some plates say that the plate gets all the way to the taylor/guttenburg without melting!
Deep Sea Vessels (Score:1)
Save The Whales! (Score:2)
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Re:Elevator Goin Down (Score:1)
Too easy. You anchor a bouy to the bottom. Link (a big carabiner will work) a heavier than water object (you can add an anchor to this if necessary) to the bouy's anchor line. Voilà, deep sea elevator.
Yeah, because so much stuff happens there... (Score:5)
Research is conducted on the ocean floor ... (Score:2)
I knew it! (Score:2)
--
MailOne [openone.com]
We're going to need deep sea technology (Score:3)
Personally I think that we're not spending enough on things like this, because at the rate that America and the rest of the first world is using up natural resources and producing pollution soon the only place left with any kind of survival and resource potential is going to be on the ocean floor near hydrothermal vents where we can life alongside the bacteria and algae.
But apart from that this is pretty interesting, and a much better use of our scientific resources than YADMP (Yet Another Doomed Mars Probe). It makes more sense to understand our own planet before we go haring off into outer space, because despite what techno-fetishists tell you, space is no solution to any of our problems, whereas the sea is a resource we haven't really begun to tap.
Like dumping nuclear waste into subduction zones. (Score:5)
Now before anyone misinterprets my words to mean "ocean dumping of nuclear waste" or says something nonsensical like "what if it 'comes up' in a volcano somewhere else", recall that ALL of the Earth's current internal heat is generated by the natural radioactive elements present in the Earth (see: http://www.newton.dep.anl.gov/askasci/env99/env087 .htm [anl.gov]).
And since most radioactive elements are heavy, they tend to sink and not come back up. Those that do reemerge to the surface are diffused across the globe and are indistinguishable from natural radioactivity.
Support subduction zone dumping of nuclear waste now! Write your legislators! Get funding allocated to research this at your local University. It *is* a good idea. And far better than anything else yet conceived of what to do with the waste.
"Why not just quit making the waste? You overlook world energy shortages."
Re:75% or earth poorly monitored (Score:1)
And the ocean has such a huge heat capacity, it will take centuries of human induced warming of the atmosphere to start bouncing the ocean's molecules more quickly.
Re:We're going to need deep sea technology (Score:5)
Pressure. On the surface of the Earth, it is about 15 psi. Going into orbit requires a pressure vessel that doesn't need to maintain a differential any more than that (15psi vs 0 psi). In the water, pressure increases by 1 atmosphere for every 33 feet of depth. Since the average depth of the ocean is 4,000 meters, any sub-surface vehicle suited for deep-sea research must maintain a pressure differential on the order of 5500 psi at 4,000 meters. That is one heck of an engineering problem.
Coming home. For space exploration, we have largely solved the problem of re-entry into the atmosphere. But the same pressure differentials mentioned above present problems returning to the surface from the deep ocean. If subjected to more than 3 atmospheres of pressure, humans are limited in the amount of time they can spend in that environment before requiring decompression. In addition, submarines can only ascend or descend so fast before the rate of change of pressure begins having adverse effects on the vehicle. In submarines, pressure vessel failures tend to be catastrophic and fatal (ever hear of USS Thresher?).
There are other problems, but those are two of the biggest. Solving them requires a lot of money, time, and energy (undersea propulsion being another big challenge). It's not as easy as it first seems.
Subset of returned data (Score:3)
DSFP (Deap Sea Floor Probe) #223-K
Summary of data for 1/10/1901
Humidity: %100 +/- 0%
Light: 0 Lumens +/- 0 Lumens
Pressure: OVERFLOW
Temperature: 0.56 C
Re:Hmm... (Score:1)
Seems to me that the best way to manage the population on this planet would be to use your mass-drivers to launch idiots into space, crashing them into Mars. We'll call them "colonists".