Wrecked "ghost ships" off the Golden Gate


#1

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#2

They “Discovered” two ships that are visible from SanFran at low tide? and have been there for 100 years or more?

This no make sense.


#3

Maybe nobody happened to look in that direction?

The part I don’t get is how a ship can be “forgotten.” Aren’t they kind of… large? Usually?


#4

It’s because of the drought in California. The ocean is so much lower that all the ships that wrecked there years ago are now floating to the surface.


#5

Two different things… They discovered two ships and also completed the first sonar survey of the wrecked tankers Frank H. Buck (above) and Lyman Stewart, both of which are partially visible from San Francisco at low tide.

Here: (from TFA)

In addition to the newly identified ships, Vitad Pradith, a researcher with NOAA’s Office of Coast Survey Navigation Response Team 6, completed the first-ever sonar survey of the submerged portions of the wrecks of the tankers Frank H. Buck and Lyman Stewart. The engines of both vessels are visible at low tide

#6

Uhh… droughts do not drop ocean levels. Physics just doesn’t work like that.


#7

The land is higher because of less water weighing it down – do you even science?


#8

You’ve been had. So have I, for even replying.


#9

Not since the magnet accident.


#10

Everyone knows that when there’s a drought, metals weigh less due to lower atmospheric moisture. Thus they are floatier.


#11

Are you a frog?


#12

Buckyball soup?


#13

Approximate air as ideal gas, with the molecular weight being weighted average of molecular weights of the components. At a given temperature-pressure the amount of particles (molecules/atoms) is constant (pV=nRT). Replace part of the oxygen/nitrogen molecules with water, and the amount of particles stays but their average molecular weight decreases. So the density (kilogram/m3) goes down. So the buoyancy exerted on the metal (or any object) goes down as well if the humidity goes up. The opposite way with decreasing humidity.

So in dry air, metals actually should weigh a tiny bit less.


#14

But you forgot their increased susceptibility to dark particles when the atmospheric density of other particles decreases. When there are fewer water molecules, metals absorb more WIMPs and therefore the net effect is floatierness.


#15

My method actually works as described.

According to the air density calculator, at 20’C and normal air pressure at sea level, the air density at 0% humidity is 1.2 kg/m3, at 100% it is 1.19 kg/m3. One liter of air therefore weighs 1.20 to 1.19 grams. The difference is 10 milligrams.

Let’s assume a 10x10x10 cm block of metal. The air causes buoyancy, and the metal block will be made a little lighter, by the weight of air it displaces. (Get below the air density and the thing will float, same mechanism.)

At dry air the scales will show the same metal block to be 10 milligrams lighter than in saturated-wet air.

This is a rough approximation showing the principle and omitting details and rounding up wildly, and omitting the other factors like adsorption of water molecules on the material surface (and absorption inside, for susceptible materials).


#16

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