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New Estimates Say Earth's Oceans Smaller Than Once Believed
Velcroman1 writes with this snippet from Fox News: "Using lead weights and depth sounders, scientists have made surprisingly accurate estimates of the ocean's depths in the past. Now, with satellites and radar, researchers have pinned down a more accurate answer to that age-old query: How deep is the ocean? And how big? As long ago as 1888, John Murray dangled lead weights from a rope off a ship to calculate the ocean's volume — the product of area and mean ocean depth. Using satellite data, researchers from the Woods Hole Oceanographic Institute set out to more accurately answer that question — and found out that it's 320 million cubic miles. And despite miles-deep abysses like the Mariana Trench, the ocean's mean depth is just 2.29 miles, thanks to the varied and bumpy ocean floor."
It's bigger than a breadbox.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
So, what were the earlier estimates? I'm on Slashdot => I did not RTFA.
Do they consider the effect of evaporation? Earth loses some of its atmosphere to space constantly and it's not too improbable that some water vapor is also lost in this way...
And soon it's average depth will be 2.29 miles plus a foot or two, according to the IPCC.
Well, it was more volumous. But all those sponges soaked up so much.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
After reading the article (SHOCKING!)
I wonder if they could get ships to carry a device to collect depth and undersea mountain patterns and then aggregate the data later. Might be cheaper the 2 billion dollars.
The Kruger Dunning explains most post on
is whether they calculated the mean depth by assuming the oceans are flat with varying depth, or assuming it is spherical.
At only 2.29 miles mean depth, you'd think BP could have found a shallower place to drill.
From Article: It would take 10 ships 20 years to measure all the ocean-floor depths with an echsounder, according to published U.S. Navy estimates.
"That would come to about $2 billion," Smith says. "NASA is spending more than that on a probe to [the Jupiter moon] Europa."
Right, it costs more to send something into space. There are a lot of scientific pursuits less expensive that space travel. I'm confused...what's this comparison trying to say?
If the quote had been "Nasa is spending less than that on a probe....", then it would have offered commentary on how prohibitively expensive the project is (if true). Instead, it costs less to image the earth than image Europa. What are they saying?
For all you metric fans out there, the volume 320 × 10^6 cubic miles is approx. 133.4 × 10^7 cubic km with an average depth of 3.69 km.
BP
for suggesting climate change deniers will jump all over this as proof of their POV in 3...2...1...
320 million cubic miles = 1.33381818 × 10^18 m3
For fuck's sake, use scientific SI units regarding scientific topics.
The same imperial, US-only nonsense unit have cost a NASA probe...
2.29 miles isn't even 1 league! I thought the ocean was 20,000 leagues deep!
Could these numbers be confirmed by gravimetric measurements of the tides? The moon, sun, and to a very small extent the planet Jupiter, raise tides in the ocean and induce a gravitational moment. It seems like we could measure that and use it to approximate the mass of the oceans and therefore their volume, though off the top of my head I'm not sure about the details.
Yes, IIRC by the same mechanism Venus has a lot of relatively heavier elements (Carbon, Oxygen, Sulfur), but barely any Hydrogen if you compare it to Earth and count the oceans as part of the atmosphere.
Water (gas) is split by solar radiation higher up, and the light hydrogen is carried upwards, and some of these particles bump into each other and often enough these bumps add up to escape velocity for one particle. Supposedly solar winds also play a significant role, and as Mars and Venus don't have a magnetic field anymore to protect them, over the eons all the hydrogen was lost. One more factor for the Drake Equation!
Fox News will retract this story once they realize that it increases the percentage of the ocean filled with oil. And then denigrate the scientists involved as Marxists.
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
Erm, 12,000 feet is pretty damn deep water.
Coding with assembly is like playing with Legos. Coding an application in assembly is like building a car with Legos.
Do they include the extreme edge of the oceans (i.e. beaches) where the 'depth' is only a few millimeters? Or do they go out to sea a standard distance before they start measuring?
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
We must stop global warming!! Our oceans are getting smaller, we, um, need to, uh, what?
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
I have a challenge for you all: if the earth were a perfectly smooth sphere but with the same volume of dirt/rock as it is now, how deep would the ocean covering its surface be? (Assume no gravitational effects of the moon or whatever - just a sphere of dirt/rock, and an ocean of equal depth everywhere.)
I never thought I'd see the day when /. links to fox news.
It's a fairly well written article though. I'd say it's head and shoulders above anything they've linked to on Tom's Hardware, but that's not saying much.
moox. for a new generation.
How much oil would it take to pollute 320 million cubic miles of seawater?
Having lived their entire lives without seeing the ocean, two old women take a trip to the Pacific coast. Upon arriving on the beach, one looks out toward the horizon and says to the other, "That's funny, I thought it would be bigger."
It must have been something you assimilated. . . .
That's 3.69 kilometers!
Have gnu, will travel.
To be fair, government didn't force them to drill there. It disallowed drilling in some locations so the company evaluated risks and decided to drill there.
Now that we know how well they do evaluating risks, I am rather pleased that government put some restrictions on their drilling. Because it is clear that they choose a risk of a massive catastrophe if they believe that there are profits involved and can't be trusted in this matter. I just wish that the government(s) would have put much more restrictions in place.
valenzetti equation*
The post here is misleading on several counts.
First, the planet also gains water via asteroids and meteors that are captured via the gravity of the planet. There is speculation that this is the method by which most water on the planet arrived. The key to understanding this is realising that the planet was orbiting the Sun for a billion years or two before life appeared. That's a lot of time for it to be spinning around in space, accumulating water.
The second is that Mars still has a magnetic field, except that it is the configuration of it that causes gas to be lost:
http://science.nasa.gov/science-news/science-at-nasa/2008/21nov_plasmoids/
Nice link, thanks. They still aren't sure exactly the method that caused Mars to lose its atmosphere, but that pages shows some interesting probabilities.
Tequila: It's not just for breakfast anymore!
If we had a conservative in the White House the worlds oceans would be much deeper. Obama's version of radical politcal change has caused the worlds oceans to shrink. I am forcasting that by the end of Obama's first term in the White house the worlds oceans will have shrunk to the size of lake michigan, if he is allowed to remain in office they will shrink to the size of a rain puddle!! Beware America!!
5.59297599 × 10^18 hogsheads 3.52357487 × 10^20 US gallons 1.33381818 × 10^21 litres
Excuse me, but please get off my Pennisetum Clandestinum, eh!
failed to realize that the orbits of TOPEX/POSEIDON and JASON-1 and -2 are not managed and allowed to decay.
As the satellite orbit decays, i.e. gets closer to Earth, the ocean appears to be heigher than before,
A very simple explanation to all the psycho-babble bullshit about global mean sea level rise (GRL is full of psycho-babble these days, and for the fullfilment of psycho-babble).
On a related subject, when the oil-shit from the Gulf of Mexico washes ashore on the British Isles, and the Brits are having a chilly, a.k.a. cold summer, BP will have to answer to the Queen Mum, who by that time will be one Royal PISSED OFF Queen Mum.
Fox News will believe that scientists can measure the size of the ocean from satellite data, but start talking about temperatures and all bets are off!
Of course, now that people will be able to fish for oil right off the pier, shouldn't oil prices go down?
BTW - 640g people should be enough for everyone.
Folks who find the original post more interesting than the typical Slashdot discussion that followed might be interested in this recent work: Pressure-temperature Phase Diagram of the Earth
It discusses the possible range of "life as we know it" in the deep lithosphere.
Credo sim. - I think I am.
Sounds like some kind of fail to me. Then I see the people who viewed this also viewed "Democrats history of deceit" or something like that and I knew that yes, it really is a fail.
Just use the kiloyard. Sorted.
But remember, the litre isn't 1kg of water, it's about 1.0048kg of water.
Oh dear. Isn't THAT a terrible number!
If this is true, doesn't it mean the predicted ocean rises will all be considerably out?
Most people are taught that the ocean levels rise due to melting ice caps but thermal expansion of water is behind at least half of the predicted rise in ocean level.
If there's less water in the ocean, there'll be a smaller expansion.
It's a ditto of Rush Limbaugh.
"A big enough box could hold the world" -- Carl Sandburg
Where's your mom when we need her?
Bow-ties are cool.
Radar??? How is RADAR useful for measuring ocean volume??? The idiot author must have meant active SONAR right? Science reporting by the mainstream media is appalling. They are good at gossip and scandals and political correct-itudes but horrible at science. And they don't even known it.
The interesting thing about this piece of information is that if the entire ocean were to be placed into a sphere, it would only have a radius of about 424 miles. This seems pretty small when you think about the size of the ocean.