[HN Gopher] Almost 25% of world's seafloor now mapped
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Almost 25% of world's seafloor now mapped
Author : hhs
Score : 132 points
Date : 2022-10-17 20:37 UTC (2 hours ago)
(HTM) web link (www.hydro-international.com)
(TXT) w3m dump (www.hydro-international.com)
| Ptchd wrote:
| CSMastermind wrote:
| I remember when Google added seafloors to maps they made a plea
| to fund more complete mapping. I can't find it now but if someone
| else knows where it is then it would be interesting to look back
| at 10 years ago and see how far we've come.
| olivermarks wrote:
| Amazing to realize that 75% of the oceans - which are 70% of the
| earth's surface - are unmapped and unknown
| iso1631 wrote:
| How does that compare to the surface of the moon, or mars
| mkr-hn wrote:
| The resolution could be better, but it's still better than
| what we have of the ocean floor.
|
| https://www.google.com/moon/
| fckgw wrote:
| We know way more about the moon than we do the ocean. Most if
| not all of the moon not on the dark side is fully mapped.
| mkr-hn wrote:
| There is no permanently dark side of the moon. It's all lit
| eventually.
| ortusdux wrote:
| _The far side of the Moon is the lunar hemisphere that
| always faces away from Earth, opposite to the near side,
| because of synchronous rotation in the moon 's orbit. ...
| The hemisphere is sometimes called the "dark side of the
| Moon", where "dark" means "unknown" instead of "lacking
| sunlight" _
|
| https://en.wikipedia.org/wiki/Far_side_of_the_Moon
| messe wrote:
| While you're not wrong, the grandparent comment said that
| most of the "dark side" is not fully mapped, implying--at
| least to in reading of it--that the reason it's not
| mapped is due to it being the "dark side".
|
| In reality though, our maps of the far side of the moon
| are as good as those on the near side.
| sophacles wrote:
| If you re-read the quoted bit it addresses this "dark
| side" vs "far side":
|
| > The hemisphere is sometimes called the "dark side of
| the Moon", where "dark" means "unknown" instead of
| "lacking sunlight"
|
| [ed note: compare "dark ages"]
|
| So the "unknown" (relatively anyway) side of the moon is
| less mapped, but not because it's unlit, but because it's
| dark. The lit side of the moon is well mapped, not
| because it's always lit - sometimes it's unlit, but it's
| certainly the known bit as we've been looking at it since
| before we were human.
| BurningFrog wrote:
| 99% of what's 10 meters below the surface on land is probably
| also unknown.
| hinkley wrote:
| Soil scientists and some conservationists will tell you that
| 95% of what's a centimeter underground is unknown as well.
| JKCalhoun wrote:
| I read somewhere E. O. Wilson stating that were he to start
| over again he would go into research of life in the soil.
| He also said there is so little we understand about the
| things just beneath our feet.
| Alupis wrote:
| These sorts of things really give me pause when thinking about
| colonizing Mars and all of the hand-waiving that gets tossed
| around.
|
| We _still_ do not know a _lot_ about our own planet. What makes
| us so confident we won 't just screw up another planet with our
| lack of understanding...
| lazide wrote:
| With our current understanding and technical abilities - no
| need to worry, they'd all die shortly or bankrupt the host
| country.
| hinkley wrote:
| Miracle Max: Look, I'm retired. And besides, why would you
| want someone the King's stinking son fired? I might kill
| whoever you wanted me to miracle.
|
| Inigo: He's already dead.
|
| Miracle Max: He is, huh? I'll take a look. Bring him in.
|
| We screw up everything. The question is, can we leave places
| alone and screw up others instead? Screwing up the moon is
| probably better than screwing up Yosemite, or the Great
| Barrier Reef.
| loceng wrote:
| I was hoping this was somehow mapped in real-time to follow
| movements of ocean life. Is there any efforts to doing so, if
| it's even a reasonable endeavour?
|
| I personally think it'd be a worthwhile thing to do - but maybe
| will take such a massive amount of resources that we'll have to
| solve more pressing issues and stabilize society first before
| we'll - with precision - manage the ocean as a food source?
| roywiggins wrote:
| If it's possible to peek under the ocean in realtime to any
| significant degree, I reckon it would be the single most
| sensitive government secret: it would enable tracking nuclear
| submarines.
| [deleted]
| Someone wrote:
| Project site: https://seabed2030.org. From the FAQ, they aim for
| something better than Depth range Grid cell size
| % of world ocean floor 0- 1500 m 100 x 100 m 13.7
| 1500- 3000 m 200 x 200 m 11 3000- 5750 m 400 x 400 m 72.6
| 5750-11000 m 800 x 800 m 2.7
|
| For comparison, https://mars.nasa.gov/resources/8333/a-decade-of-
| compiling-t...:
|
| _"each observation by CTX covers a swath of ground about 18.6
| miles (30 kilometers) wide, at a resolution of about 20 feet (6
| meters) per pixel"_
|
| Not having oceans makes this a lot easier.
| stjohnswarts wrote:
| I honestly assumed it was more than this.
| sklargh wrote:
| This is an impressive accomplishment. Not that we'll get to find
| out in a timely manner but I am curious how these maps compare to
| bathymetric surveys in the classified submarine world.
| xen2xen1 wrote:
| Yes, I hear "undersea mapping" and I go to "a high speed run"
| in my head from "The Hunt for Red October". Funny how
| commercial or even free catches up with military applications.
| rngname22 wrote:
| Will be interesting this century to see if increased sensor
| coverage in the ocean leads to more detection of USOs
| (unidentified submerged objects). Would love it if a curious
| billionaire would fund detection systems as anecdotally it seems
| USO and UFO (same thing?) activity is centered around oceans and
| coasts, especially off Santa Catalina Island as well as Virginia
| Beach.
| b33j0r wrote:
| *UAP. There is something going on, but it's very unclear what
| it is. Hard to tell right now if the "threat" knows it's
| targeting military (might even be us), or if the military has
| the only sensors/opportunities to have these encounters.
|
| That said, let's speed this up. The Kraken is always in the
| last 5%, and C'thulhu is always the very last place you look.
| Darkphibre wrote:
| > C'thulhu is always the very last place you look.
|
| Inverse survivorship bias: That's because you are no longer
| able to look elsewhere...
| hinkley wrote:
| Would an ROV even register C'thulhu if it saw it?
| SamPatt wrote:
| Who pays for these mapping efforts, and why?
| walrus01 wrote:
| I'm less certain on the payment part, but having a very
| accurate bathymetric survey of the entire path is important for
| inter-continental submarine fiber optic cable laying. The cable
| ship needs to know _precisely_ what speed to maintain at every
| point in the path and how rapidly to pay out the cable for it
| to not lay taut across underwater valleys, and to conform to
| the shape of the bottom.
| Trouble_007 wrote:
| Remembering that the Ocean floor topography is not fixed. _' new
| island formed'_
|
| A new island is forming in the Pacific Ocean after an underwater
| volcanic eruption : https://www.cbsnews.com/news/new-island-
| pacific-ocean-volcan...
|
| List of new Islands :
| https://en.m.wikipedia.org/wiki/List_of_new_islands
| hinkley wrote:
| Last I heard we're due a new Hawaiian island in about 5
| thousand years. Loihi is still almost a kilometer down and
| slowly climbing.
| [deleted]
| [deleted]
| redleggedfrog wrote:
| Yes, but can we buy it yet?
| [deleted]
| vavooom wrote:
| "Ocean floor topography also helps identify underwater hazards
| and inform sustainable marine resource management and
| infrastructure development."
|
| Likely to inform and fuel the Rare Earth mining already being
| done on the ocean floor. Take for example off the West Coast of
| North America: https://www.cbsnews.com/news/rare-earth-elements-
| u-s-on-side...
| psychphysic wrote:
| One of my favourite stories is how deep sea mining was started
| because the CIA went overboard (pun intended) with a cover
| story [0].
|
| [0] https://www.bbc.co.uk/news/resources/idt-sh/deep_sea_mining
| walrus01 wrote:
| see also: https://www.google.com/search?client=firefox-
| b-d&q=the+jenni...
| JWLong wrote:
| See also: https://en.wikipedia.org/wiki/Glomar_response
| walrus01 wrote:
| > Ocean floor topography also helps identify underwater hazards
|
| You think the ocean is mostly empty, until your nuclear powered
| attack submarine runs into a previously uncharted (or
| incorrectly charted) submarine mountain
|
| https://www.cnn.com/2021/11/04/asia/submarine-uss-connecticu...
|
| https://www.npr.org/2021/11/02/1051422572/navy-submarine-nuc...
|
| It's happened more than once...
|
| On 8 January 2005 at 02:43 GMT, San Francisco collided with an
| undersea mountain about 364 nautical miles (675 km) southeast
| of Guam while operating at flank (maximum) speed at a depth of
| 525 feet (160 m).
|
| https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711)
| TedDoesntTalk wrote:
| I don't get it. Was their sonar broken?
| kmill wrote:
| > Submarines do have their own sonar, but using it comes at
| a price - loss of stealthiness.
| encryptluks2 wrote:
| Is there not reliable alternatives to sonar that would
| maintain stealth?
| mlindner wrote:
| They're in a place where there is no lights and no sound.
| You have to emit something whether that be in the form of
| sound or in the electromagnetic spectrum in order to
| receive a reflection back and emissions remove stealth.
|
| Not to mention that sonar is highly disruptive to many
| forms of sea life as it's incredibly loud.
| walrus01 wrote:
| the only thing I could possibly think of are receive-only
| apparatus like magnetometers, which are themselves used
| by low flying aircraft and surface ships to _locate_
| submarines. And likely of very limited value in
| underwater navigation unless you 're in a research
| submarine literally hovering a few meters above some
| rocky metallic outcroping on a seamount.
|
| Or something thermal sensor based, there's rumored to be
| systems that submarines can use passively to follow and
| track other submarines by the waste heat put into the
| water.
| Arainach wrote:
| What do you propose? Any sonar-equivalent involves
| broadcasting (in this context, broadcasting nearly
| continuously). Any broadcast makes it trivial to locate
| you.
|
| Submarines go to great lengths to be as quiet as possible
| so that the acoustics of the engine, ship, etc. can't be
| caught in a microphone. Any sort of EM radiation is
| child's play to trace compared to that. The content of
| the message and the frequency of the message don't matter
| - any sort of signal means you can be monitored and your
| location determined.
| throwaway09223 wrote:
| Well, an obvious proposal would be to send out a drone
| and transmit the sonar ping from a different location.
|
| You're right in that a broadcast is required, but I don't
| see why the broadcast should have to come from the sub
| itself.
| Arainach wrote:
| The threat model isn't a torpedo, it's knowing where the
| enemy's subs are (and aren't). "There's a sub within half
| a mile of this point" is likely 90% as bad as "there's a
| sub exactly here" for most missions.
|
| While water motors are not exactly my area of expertise,
| I would also expect that drone/torpedo motors are
| significantly louder than submarine engines and that
| launching or recovering a drone is itself a fairly noisy
| event that exposes the sub to traditional acoustic
| tracking.
| throwaway09223 wrote:
| Sure, all valid issues. It for sure would expose the
| general vicinity.
|
| In terms of noise, keep in mind that submarines have all
| sorts of concessions already. A diesel-electric sub is
| quieter than a nuclear sub, but it has to surface every
| two days or so to get air to run its very noisy diesel
| generators.
|
| I think a battery powered electric drone should be far
| quieter than any sub technology we have (steam/nuke is
| loud, diesel is louder). The quiet systems we have are
| all electric and therefore have limited energy capacity.
| throwaway09223 wrote:
| Sure. You can transmit the sonar from a different
| location. A hidden sub could send out a drone to make the
| sonar pings from a different location. You'll be giving
| away the location of the drone, rather than the sub.
| There's still an issue around detecting that a sub is in
| the general vicinity, of course.
| walrus01 wrote:
| or more conventionally, you build a fleet of
| oceanographic survey ships which operate in the open
| navigating international waters, collecting vast data
| sets of bathymetric information... obviously not perfect
| yet.
|
| https://en.wikipedia.org/wiki/Pathfinder-
| class_survey_ship
|
| there is also the danger that a drone emitting sonar
| pings may be indistinguishable to a third party from a
| live torpedo, and makes it look like you're preparing to
| attack somebody you really don't want to start a war with
| (China, etc).
| [deleted]
| walrus01 wrote:
| military submarines do not as a matter of practice run
| around in general navigation pinging things, because that
| kind of defeats the purpose of hiding where you are
| jcampbell1 wrote:
| The passive sonar from their own prop noise would easily
| show a mountain. There is a reason about 30 people were
| demoted due to the incident. Bottom line is they weren't
| paying attention to their sonar.
| [deleted]
| RcouF1uZ4gsC wrote:
| Every time I read about seafloor mapping, my mind immediately
| jumps to MH 370.
|
| https://en.wikipedia.org/wiki/Malaysia_Airlines_Flight_370
|
| A large airliner carrying more than 200 people disappeared, and
| over the past 8 years, we still have not found the main body of
| the airplane or the black boxes.
| rexreed wrote:
| That's also the first thing I think about. The disappearance of
| MH370 and the inability to find it combined with sea floor
| mapping always makes me wonder. I've always fantasized about
| the idea of autonomous seafloor mapping drones.
| jmyeet wrote:
| It's really a testament to just how large the ocean is.
| Remember there's more than twice as much sea than land and we
| lose things on land too. Things on land might not be under 3
| miles of water that takes expensive, specialized equipment in
| remote locations to actually reach.
|
| I do hope for a resolution for MH370 one day but we know the
| bullet points: it was a deliberate action by the pilot
| (and/or the co-pilot) to depressurize the plane, run it out
| into the ocean and (most likely) make a "soft" landing after
| which it would fill with water and sink. There's alot of
| evidence for this and no other proposed scenario fits the
| evidence.
| wongarsu wrote:
| The fuselage of a Boeing 777 has a diameter of about 3.7
| meters, or about 12 feet. So you're looking for something
| that's less than 4 meters high, and less than 4 meters wide. If
| it is more or less intact the wreck might be pretty long, so on
| a reasonably flat ocean floor you might pick it out at 10
| meters resolution, but in less ideal conditions you might need
| closer to 2m resolution to make it stand out against the
| background. There are the wings, which are very big, but also
| very thin, so their usefulness really depends on how they are
| angled.
|
| What we have are pretty good 400x400m maps, and increasingly
| more 100x100m maps.
| walrus01 wrote:
| Even if we assume the whole fuselage is intact in one piece,
| with the wings broken off, it's possible that it fell into
| the mud, silt and soft squishy bottom on some abyssal plain
| and is more than 1/3rd buried. Making it even harder to
| locate than a cylinder resting on a rocky surface.
| GekkePrutser wrote:
| Oh yes just posted something similar, I didn't see this post
| first.
|
| Indeed the same thing I was thinking of, I wonder if this
| seafloor mapping thing will eventually discover the plane.
| Though perhaps the resolution is not adequate?
|
| Edit: Someone (actual username :) ) just posted above that the
| grid cells are between 100x100m and 800x800m so that does
| indeed not sound adequate to detect a 777 accurately, sadly.
| The whole thing would easily fit into one grid cell of the
| smallest dimension.
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