Spammers got the last thread, the price of allowing unregistered posts I suppose.

Here comes the "global warming caused the Volcano in Iceland" headlines!





I wonder if this article just got a stealth update?

I think it's divine retribution for not paying us the money they owe

Wow! A genyoowine, relativistic effect, no less! I must pop down to the seaside with my bucket and spade to see this for myself. I'm sure it's a must-see for Dave the camerMoron too. I had better collect some dog shit on my way ready to spray on him for that 'authentic' experience he so craves.

Meanwhile, I wonder just how big the 'heavier' effect would be per degree K. Let's see. Additional heat per kg per degree K is about 4200 joules. Mass equivalent thereof 4200/(c^2) = 4.7 x 10 ^-14 kg. Resulting additional 'heaviness' is about 5 parts in 100 trillion.

A real Earth buster, then.

Correct me if I am wrong - I know things expand with increased heat but I'm not sure about them getting heavier...

The increased heat content does actually make it more 'massive', hence heavier. But this is a relativistic effect.

This is where that famous E = mc^2 comes in. But it's not detectable (5 parts in 100 trillion per degree K). So she's talking bollocks.


P.S. I should have expanded on that a little. In Einstein's theory, energy has an equivalent mass associated with it. Heat is energy, so that has associated mass. The equation relating the two is E = mc^2, where c is the speed of light, about 3 x 10^8 metres per second. If a kilogram of water has its temperature raised by one degree K (one degree Celsius, same thing) then the heat energy contained in that water has risen by about 4,200 joules. (This is just one of those things that can easily be measured in a laboratory. It's a standard measurement/experiment in O-Level school physics.)

By the equation, the mass equivalent of that heat is given by m = E/c^2, i.e. the increase in mass = 4200 / (3 x 10^8)^2 = 4200 / (9 x 10^16) = about 4.7 x 10^-14 kilograms. So it does get heavier but it's undetectable, pretty much.

For different reasons (centrifugal forces, distance from Earth's centre, and inhomogeneity in Earth's crustal density) your own weight ('heaviness' )can vary by as much as about 0.5%, depending on where you are on the planet. Of course the same applies to water too. You never notice it though. The effect above is 100 billion times weaker.

Heh, alarms did go off..

some more back of the box maths shows that the entire hydrosphere would increase by 65,800 metric tons per degree (total weight according to wikipedia is 1,400,000,000,000,000,000 metric tons).

It would be amusing to compare this weight with that of people swimming at any one time.

(Ammended for accuracy)

Good comparison.

Or filling a 1 km square pond to a depth of just under a foot.
Anyone know the current tonnage of the Royal Navy??

Cobalt, Sandy, and everyone else.

Apologies for my calculational cockups and the knock-on effects. I have corrected my own.

Cobalt,
I have also amended your figure from 280,000 tonnes to 66,000 tonnes in my quotation of it. Perhaps you could amend your original too, just to prevent further confusion of other readers here.

Sandy,
It seems your calculation also relied on my incorrect original figure. I make the depth now about 2.5 inches!

Sorry about all this. But if you check and make the relevant silent edits, I'll delete this red-herring error post too.

This talk of mass, water etc got me thinking: How much of sea level rises could be 'blamed' on the displacement of ships? And erosion. And new land creation.

A thought occurs ... if they chop down all the trees in the Amazon, the rain stops falling, the land turns to desert and the river dries up. No more water will pour into the ocean and the level will drop. Simples.

Interesting, but I suppose you'd have to subtract any water artificially held back by dams etc.

Besides. I thought that water levels were more likely to be affected by tectonic bounce than anything else. Sea levels around Northern Europe are dropping as the land masses that used to be under so much ice revert to their normal height whereas Southern Europe is sinking as a knock-on effect (or something like that). Think of what happens when you sit on a water bed and then stand up again (but in veeeeeery slow motion)

Did the earth move for you, darling?

veeeeeery slowly.