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Day length and ice melt

Tim the plumber

Tim the plumber

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When the ice melts at the poles it spreads the water all around the world. This moves mass from the poles to the equator and everywhere else.

Here is my maths to show what this would do to the day length;

Take the moment of initeria of a hollow sphere of negligable thickness 2m[SUB]1mm[/SUB]r[SUP]2[/SUP]/3 and divide by the total moment of inertia for the entire earth m[SUB]e[/SUB]r[SUP]2[/SUP]/2.

The r[SUP]2[/SUP] cancells as it's the same. The m[SUB]1mm[/SUB] is the mass of a 1mm layer of water over the whole earth. The m[SUB]e[/SUB] is the mass of the whole earth.

So, m[SUB]1mm[/SUB] x4
________________ = (360 x 10[SUP]12[/SUP]kg / 6 x 10[SUP]24[/SUP]) x 4/3 = 6 x 10[SUP]-11[/SUP]

m[SUB]e[/SUB] x3


This is the fraction that the world's spin is slowed by.

Multiply this by the number of seconds in a year 31.5 x 10[SUP]6[/SUP]

So that is 1.9 x 10[SUP]-3[/SUP] or 1.9 thousanths of a second per mm of sea level rise.

This is not noticable in human terms but it is easily measurable with atomic clocks. It has not happened. We are supposed to have had at least 180mm of this ea level rise since 1900. It has not happened. There is no explaination for why this has not happened other than the measurement of the ice melt from Greenland etc is wrong.

My maths is very rusty, like 30 years since I did any of this, so please correct me if I've droped one.
 
Perhaps it has happened in a different way given the reports that the north pole which was drifting toward the US is now drifting toward the UK.
 
Tim the plumber said:
When the ice melts at the poles it spreads the water all around the world. This moves mass from the poles to the equator and everywhere else.

Here is my maths to show what this would do to the day length;

Take the moment of initeria of a hollow sphere of negligable thickness 2m[SUB]1mm[/SUB]r[SUP]2[/SUP]/3 and divide by the total moment of inertia for the entire earth m[SUB]e[/SUB]r[SUP]2[/SUP]/2.

The r[SUP]2[/SUP] cancells as it's the same. The m[SUB]1mm[/SUB] is the mass of a 1mm layer of water over the whole earth. The m[SUB]e[/SUB] is the mass of the whole earth.

So, m[SUB]1mm[/SUB] x4
________________ = (360 x 10[SUP]12[/SUP]kg / 6 x 10[SUP]24[/SUP]) x 4/3 = 6 x 10[SUP]-11[/SUP]

m[SUB]e[/SUB] x3


This is the fraction that the world's spin is slowed by.

Multiply this by the number of seconds in a year 31.5 x 10[SUP]6[/SUP]

So that is 1.9 x 10[SUP]-3[/SUP] or 1.9 thousanths of a second per mm of sea level rise.

This is not noticable in human terms but it is easily measurable with atomic clocks. It has not happened. We are supposed to have had at least 180mm of this ea level rise since 1900. It has not happened. There is no explaination for why this has not happened other than the measurement of the ice melt from Greenland etc is wrong.

My maths is very rusty, like 30 years since I did any of this, so please correct me if I've droped one.
Click to expand...

Your entire exposition falls afoul of the "correlation is not causation" logical fallacy. That, and you've built a strawman about the "at least 180mm" sea level rise that you claim didn't happen since the turn of the century...when in actuality:

Proxy and instrumental sea level data indicate a transition in
the late 19th century to the early 20th century from relatively
low mean rates of rise over the previous two millennia to
higher rates of rise (high confidence). It is likely that the rate
of global mean sea level rise has continued to increase since
the early 20th century, with estimates that range from 0.000
[–0.002 to 0.002] mm yr to 0.013 [0.007 to 0.019] mm yr. It
is very likely that the global mean rate was 1.7 [1.5 to 1.9] mm yr
between 1901 and 2010 for a total sea level rise of 0.19 [0.17 to 0.21]
m. Between 1993 and 2010, the rate was very likely higher at 3.2 [2.8
to 3.6] mm yr; similarly high rates likely occurred between 1920 and
1950.
 
Tim the plumber said:
When the ice melts at the poles it spreads the water all around the world. This moves mass from the poles to the equator and everywhere else.

Here is my maths to show what this would do to the day length;

Take the moment of initeria of a hollow sphere of negligable thickness 2m[SUB]1mm[/SUB]r[SUP]2[/SUP]/3 and divide by the total moment of inertia for the entire earth m[SUB]e[/SUB]r[SUP]2[/SUP]/2.

The r[SUP]2[/SUP] cancells as it's the same. The m[SUB]1mm[/SUB] is the mass of a 1mm layer of water over the whole earth. The m[SUB]e[/SUB] is the mass of the whole earth.

So, m[SUB]1mm[/SUB] x4
________________ = (360 x 10[SUP]12[/SUP]kg / 6 x 10[SUP]24[/SUP]) x 4/3 = 6 x 10[SUP]-11[/SUP]

m[SUB]e[/SUB] x3


This is the fraction that the world's spin is slowed by.

Multiply this by the number of seconds in a year 31.5 x 10[SUP]6[/SUP]

So that is 1.9 x 10[SUP]-3[/SUP] or 1.9 thousanths of a second per mm of sea level rise.

This is not noticable in human terms but it is easily measurable with atomic clocks. It has not happened. We are supposed to have had at least 180mm of this ea level rise since 1900. It has not happened. There is no explaination for why this has not happened other than the measurement of the ice melt from Greenland etc is wrong.

My maths is very rusty, like 30 years since I did any of this, so please correct me if I've droped one.
Click to expand...

I found you post interesting but I think the length of the day is affected by several things. Like the pull of the moon. So you would have to differentiate among all the different forcings to determine how much the increase in sea level affected the time. Maybe it can be done but I'd think it would be very difficult.
 
Glen Contrarian said:
Your entire exposition falls afoul of the "correlation is not causation" logical fallacy. That, and you've built a strawman about the "at least 180mm" sea level rise that you claim didn't happen since the turn of the century...when in actuality:

Proxy and instrumental sea level data indicate a transition in
the late 19th century to the early 20th century from relatively
low mean rates of rise over the previous two millennia to
higher rates of rise (high confidence). It is likely that the rate
of global mean sea level rise has continued to increase since
the early 20th century, with estimates that range from 0.000
[–0.002 to 0.002] mm yr to 0.013 [0.007 to 0.019] mm yr. It
is very likely that the global mean rate was 1.7 [1.5 to 1.9] mm yr
between 1901 and 2010 for a total sea level rise of 0.19 [0.17 to 0.21]
m. Between 1993 and 2010, the rate was very likely higher at 3.2 [2.8
to 3.6] mm yr; similarly high rates likely occurred between 1920 and
1950.
Click to expand...

That's my point.

The data from tidal guages says one thing but the much more accuracte in terms of global sea level data from day length/atomic clocks says that the general sea level has not changed.
 
backpacker said:
Perhaps it has happened in a different way given the reports that the north pole which was drifting toward the US is now drifting toward the UK.
Click to expand...

Any such changes in position of ice can be easily modeled and the effect is very low compared to the effect of moving from the pole to the equator.
 
Speaking of ice melts, I believe this is the second-lowest ever Arctic ice cover recorded.
 
Threegoofs said:
Into the hollow earth that you are assuming!
Click to expand...

What are you talking about???

Do you understand the assumptions I have made in the very simple model I have used? Can you work out how, to what degree, it's wrong?
 
Tpaine said:
I found you post interesting but I think the length of the day is affected by several things. Like the pull of the moon. So you would have to differentiate among all the different forcings to determine how much the increase in sea level affected the time. Maybe it can be done but I'd think it would be very difficult.
Click to expand...

The pull of the moon is the same this month as last. That is not going to change the time for a year to happen beyond the known effects of very gradually lengthening the day. This is easy to add into the model.
 
Tim the plumber said:
What are you talking about???

Do you understand the assumptions I have made in the very simple model I have used? Can you work out how, to what degree, it's wrong?
Click to expand...

Well, you assume the earth is hollow.

Its not.

I see no reason to entertain your fantasy beyond that point.
 
Tim the plumber said:
When the ice melts at the poles it spreads the water all around the world. This moves mass from the poles to the equator and everywhere else.

Here is my maths to show what this would do to the day length;

Take the moment of initeria of a hollow sphere of negligable thickness 2m[SUB]1mm[/SUB]r[SUP]2[/SUP]/3 and divide by the total moment of inertia for the entire earth m[SUB]e[/SUB]r[SUP]2[/SUP]/2.

The r[SUP]2[/SUP] cancells as it's the same. The m[SUB]1mm[/SUB] is the mass of a 1mm layer of water over the whole earth. The m[SUB]e[/SUB] is the mass of the whole earth.

So, m[SUB]1mm[/SUB] x4
________________ = (360 x 10[SUP]12[/SUP]kg / 6 x 10[SUP]24[/SUP]) x 4/3 = 6 x 10[SUP]-11[/SUP]

m[SUB]e[/SUB] x3


This is the fraction that the world's spin is slowed by.

Multiply this by the number of seconds in a year 31.5 x 10[SUP]6[/SUP]

So that is 1.9 x 10[SUP]-3[/SUP] or 1.9 thousanths of a second per mm of sea level rise.

This is not noticable in human terms but it is easily measurable with atomic clocks. It has not happened. We are supposed to have had at least 180mm of this ea level rise since 1900. It has not happened. There is no explaination for why this has not happened other than the measurement of the ice melt from Greenland etc is wrong.

My maths is very rusty, like 30 years since I did any of this, so please correct me if I've droped one.
Click to expand...

I'm not going to check your math, but the concept is great!

there should be a measurable difference by atomic clocks.
 
Tim the plumber said:
The pull of the moon is the same this month as last. That is not going to change the time for a year to happen beyond the known effects of very gradually lengthening the day. This is easy to add into the model.
Click to expand...

Agreed but it still has to be accounted for because the change do to movement of water is very gradual also.
 
Tpaine said:
Agreed but it still has to be accounted for because the change do to movement of water is very gradual also.
Click to expand...

It can be accounted for. It is a known variable. I suspect someone will now do such proper math.
 
Threegoofs said:
Well, you assume the earth is hollow.

Its not.

I see no reason to entertain your fantasy beyond that point.
Click to expand...

I assume that a 1mm addition to the sea level will be a hollow sphere all over the world. Not quite but close enough.

You have failed to understand the maths.
 
Tim the plumber said:
I assume that a 1mm addition to the sea level will be a hollow sphere all over the world. Not quite but close enough.

You have failed to understand the maths.
Click to expand...

Is that unexpected?
 
Tpaine said:
Agreed but it still has to be accounted for because the change do to movement of water is very gradual also.
Click to expand...

Gradual but continious. It is not something that will go backwards. Unlike changes of a temporary nature such as weather effects.
 
Tim the plumber said:
Gradual but continious. It is not something that will go backwards. Unlike changes of a temporary nature such as weather effects.
Click to expand...

But the cyclicity of celestial bodies is ever changing, as they all interact with each other. It's a more complex problem than most people realize.
 
Lord of Planar said:
But the cyclicity of celestial bodies is ever changing, as they all interact with each other. It's a more complex problem than most people realize.
Click to expand...

There is a gradual effect of the tides making the day length longer adn also increasing the orbit of the moon. It is a known constant.

The rest of the solar system is negligable in these terms. And again easy (for an astronomer, not somebody who has not done algerbra for 30 years) to model.
 
Tim the plumber said:
There is a gradual effect of the tides making the day length longer adn also increasing the orbit of the moon. It is a known constant.

The rest of the solar system is negligable in these terms. And again easy (for an astronomer, not somebody who has not done algerbra for 30 years) to model.
Click to expand...

I wouldn't call it a constant, but over a given period of time has a near linear value of change. For a confined error limit, it can be stated as a constant, but it really isn't.
 
WCH said:
Cavernous areas where springs originate, into volcanoes, heated into vapor, etc. Just a thought.
Click to expand...

Springs come out of the ground when the water table, the top of the saturated rock, hits the surface. If there are any cavities below this layer then they are already filled with water and we are talking about billions of tonnes of water. 360 billion per mm.

If the water becomes water vapor it will rain out of the air quickly. It will also be spread allover the world.
 
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