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Day length and ice melt

Tim the plumber said:
For the fourth time!!![4]

I assume that the whole earth is solid. That it is a solid sphere. That the additional 1mm of sea water on top of it is hollow with the earth inside it!!! NOT HARD!!
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Whatever. You assume that the earth is solid, when it will change density and shape based upon ice melt. You assume the oceans are a hollow sphere, where they are unevenly distributed on the surface.

Its all just idiotic, in that there are published papers on this issue which you apparently never looked up and when I posted one, you didnt understand it.
 
Tim the plumber said:

The point is that low desity water at the equator will stick out away from the axis of spin further than the changes in higher density rock will move twoards the axis especially as the vertical movement at high latitudes is much more pararllel to said axis.

If you are saying that the ocean floor is moving up and down at rates we do not know about, well, that would make any talk of having a graph of sea level change utterly meaningless. It would take away one of the pillars of the AGW faith!!!
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Ok I finally decided to check the math. The formula for calculating the change in rotational velocity is based on the conservation of rotational momentum. That formula is:

I1 V1 = I2 V2

Therefore:

V2 = I1 V1/I2

I1 is equal to 2/5 M1 r1^2 and I2 is equal to 2/5 M2 r2^2 where:

M2 = M1 + the mass of 1 mm of water on the surface which can be calculated as 4 x pi x r1^2 x 0.001 x 1000 kg/m^3

R2 = r1 + .001 meter.

The rotational velocity of the earth V1 would be:

One rotation = 1/(24 x 60 x 60) = 1.157407E-5 rotations/sec

After obtaining those numbers it is easy to calculate V2 from the formula above and subtract V1 from V2. When you do that you get a difference of

4.63415283-15 seconds

Or for 180 mm

8.3414714E-13 seconds

It’s not quite 180 times the 1 mm value since it’s not linear but it’s close. What you were doing is not correct.
 
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.
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So, your 30 year old rusty math proves that sea levels haven't risen?
 
Threegoofs said:
Whatever. You assume that the earth is solid, when it will change density and shape based upon ice melt. You assume the oceans are a hollow sphere, where they are unevenly distributed on the surface.

Its all just idiotic, in that there are published papers on this issue which you apparently never looked up and when I posted one, you didnt understand it.
Click to expand...

For pratcile purposes of this model the simplification of the earth being a uniform sphere is reasonable. The simplification of the land being uniformly spread over all latitudes is also reasonable when I need a result only to be to within 20% accuracy. It is better than that.

The paper you linked to, nobody has understood. We, on this sub forum, are generally good at reading complex papers. That nobody can make anything of it says it all. The paper you cited is attempting to baffle with bull****.
 
Tpaine said:
Ok I finally decided to check the math. The formula for calculating the change in rotational velocity is based on the conservation of rotational momentum. That formula is:

I1 V1 = I2 V2

Therefore:

V2 = I1 V1/I2

I1 is equal to 2/5 M1 r1^2 and I2 is equal to 2/5 M2 r2^2 where:

M2 = M1 + the mass of 1 mm of water on the surface which can be calculated as 4 x pi x r1^2 x 0.001 x 1000 kg/m^3

R2 = r1 + .001 meter.

The rotational velocity of the earth V1 would be:

One rotation = 1/(24 x 60 x 60) = 1.157407E-5 rotations/sec

After obtaining those numbers it is easy to calculate V2 from the formula above and subtract V1 from V2. When you do that you get a difference of

4.63415283-15 seconds

Or for 180 mm

8.3414714E-13 seconds

It’s not quite 180 times the 1 mm value since it’s not linear but it’s close. What you were doing is not correct.
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Surely all we need do is know the fraction of the difference that adding 1mm to the over all sea level will do. That is much easier and I can't see it being different from going throught the detail of working out the change in m/s.

I don't quite get your maths but... what impact would a 1mm sea level rise have on the whole earth? Are your numbers for a day or a year?
 
Tim the plumber said:

The point is that low desity water at the equator will stick out away from the axis of spin further than the changes in higher density rock will move twoards the axis especially as the vertical movement at high latitudes is much more pararllel to said axis.

If you are saying that the ocean floor is moving up and down at rates we do not know about, well, that would make any talk of having a graph of sea level change utterly meaningless. It would take away one of the pillars of the AGW faith!!!
Click to expand...

We do know about the ocean floor moving down and we do correct for it. Averaged over the global ocean surface, the mean rate of sea level change due to glacial isostatic adjustment is independently estimated from models at -0.3 mm/yr. In some regions, such as the Caribbean, the ocean floor is moving down at a higher rate; in other areas, such as the South Pacific, it is barely moving at all.

What is glacial isostatic adjustment (GIA), and why do you correct for it?

The net movement of rock from places such as the Caribbean to Canada is of a similar magnitude to the movement of water from the polar regions to the rest of the oceans and will have a comparable effect on the Earth's rotation. You cannot simply ignore it.
 
Surface Detail said:
We do know about the ocean floor moving down and we do correct for it. Averaged over the global ocean surface, the mean rate of sea level change due to glacial isostatic adjustment is independently estimated from models at -0.3 mm/yr. In some regions, such as the Caribbean, the ocean floor is moving down at a higher rate; in other areas, such as the South Pacific, it is barely moving at all.

What is glacial isostatic adjustment (GIA), and why do you correct for it?

The net movement of rock from places such as the Caribbean to Canada is of a similar magnitude to the movement of water from the polar regions to the rest of the oceans and will have a comparable effect on the Earth's rotation. You cannot simply ignore it.
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I followed this idea around a bit and came to this;

https://www.ngdc.noaa.gov/mgg/bathymetry/predicted/explore.HTML

Prediction of Seafloor Depth

We are using these dense satellite altimeter measurements in combination with sparse measurements of seafloor depth to construct a uniform resolution map of the seafloor topography. These maps do not have sufficient accuracy and resolution to be used to assess navigational hazards but they are useful for such diverse applications as locating the obstructions/constrictions to the major ocean currents and locating shallow seamounts where fish and lobster are abundant.
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The reason that the ocean floor, especially the southern hemisphere oceans, is so poorly charted is that electromagnetic waves cannot penetrate the deep ocean (3-5 km = 2-3 mi). Instead, depths are commonly measured by timing the two-way travel time of an acoustic pulse. However because research vessels travel quite slowly (6m/s = 12 knots) it would take approximately 125 years to chart the ocean basins using the latest swath-mapping tools. To date, only a small fraction of the sea floor has been charted by ships.

Fortunately, such a major mapping program is largely unnecessary because the ocean surface has broad bumps and dips which mimic the topography of the ocean floor. These bumps and dips can be mapped using a very accurate radar altimeter mounted on a satellite. In this brief report we attempt to answer some basic questions related to satellite measurements of the ocean basins. What causes the surface of the ocean to bulge outward and inward mimicking the topography of the ocean floor? How big are these bumps? How can they be measured in the presence of waves and tides? What are some of the non-military applications of these data? What has been discovered from the new Geosat and ERS-1 data?
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And you are telling me that we know what the sea floor is doing to tenths of mm. Ummmmmm.....
 
Tim the plumber said:

I followed this idea around a bit and came to this;

https://www.ngdc.noaa.gov/mgg/bathymetry/predicted/explore.HTML

Prediction of Seafloor Depth





And you are telling me that we know what the sea floor is doing to tenths of mm. Ummmmmm.....
Click to expand...

The movements of the Earth's crust due to glacial isostatic adjustment are determined from a combination of measurement and modelling and are estimated to be accurate to +/- 20% or so, but it remains an active area of research. Your approach of simply assuming that GIA is negligible because it is tricky to determine accurately is illogical, especially when we know that the movements involved are of a similar order of magnitude to the movements of water.

By the way, what data are you using for measurements of the Earth's rotation?
 
Tim the plumber said:

And you are telling me that we know what the sea floor is doing to tenths of mm. Ummmmmm.....
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Seems like a stretch to me.

Changes in temperature, salinity, and other variables will affect what ever means they use to measure it.

It is probable another calculated model idea, with very large error margins.
 
Surface Detail said:
The movements of the Earth's crust due to glacial isostatic adjustment are determined from a combination of measurement and modelling and are estimated to be accurate to +/- 20% or so, but it remains an active area of research. Your approach of simply assuming that GIA is negligible because it is tricky to determine accurately is illogical, especially when we know that the movements involved are of a similar order of magnitude to the movements of water.

By the way, what data are you using for measurements of the Earth's rotation?
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Given that we are told that the level of accuracy of sea level rise is suficent to know that it's due to AGW your point is just as damaging to that idea.

I am happy to go with the "we don't know" thing but this will apply to all sides of the argument.
 
Tpaine said:
Ok I finally decided to check the math. The formula for calculating the change in rotational velocity is based on the conservation of rotational momentum. That formula is:

I1 V1 = I2 V2

Therefore:

V2 = I1 V1/I2

I1 is equal to 2/5 M1 r1^2 and I2 is equal to 2/5 M2 r2^2 where:

M2 = M1 + the mass of 1 mm of water on the surface which can be calculated as 4 x pi x r1^2 x 0.001 x 1000 kg/m^3

R2 = r1 + .001 meter.

The rotational velocity of the earth V1 would be:

One rotation = 1/(24 x 60 x 60) = 1.157407E-5 rotations/sec

After obtaining those numbers it is easy to calculate V2 from the formula above and subtract V1 from V2. When you do that you get a difference of

4.63415283-15 seconds

Or for 180 mm

8.3414714E-13 seconds

It’s not quite 180 times the 1 mm value since it’s not linear but it’s close. What you were doing is not correct.
Click to expand...

Having had a think about it, the value you are using for the moment of inertia of the earth is going to be very big compared to the difference between the first value and the second with the extra mm on r. This difference will be likely to be lost in the mist of the computer's calculations. It being of the order of a billionth of the radius of the earth. Which is then squared. I don't think you will get a decent answer.

The next difference is that I have used the surface area of the oceans for the value of 360 billion tonnes of water for a 1mm sea level rise.
 
Tim the plumber said:
Given that we are told that the level of accuracy of sea level rise is suficent to know that it's due to AGW your point is just as damaging to that idea.

I am happy to go with the "we don't know" thing but this will apply to all sides of the argument.
Click to expand...

The effect of GIA on sea level is roughly 0.3 mm/year. This is relatively small compared with the currently measured value of sea level rise of 3.4 mm/year. Even if the effect of GIA is out by 50%, that still only about a 5% error in the rate of change of sea level.

It's more critical to rotation speed, though, because:
1) Rock is much heavier than water, and
2) The largest movements are on land rather than at sea.

You can't just ignore it.

Anyway, where is this rotation speed data that you're referring to?
 
Tim the plumber said:
For pratcile purposes of this model the simplification of the earth being a uniform sphere is reasonable. The simplification of the land being uniformly spread over all latitudes is also reasonable when I need a result only to be to within 20% accuracy. It is better than that.

The paper you linked to, nobody has understood. We, on this sub forum, are generally good at reading complex papers. That nobody can make anything of it says it all. The paper you cited is attempting to baffle with bull****.
Click to expand...

So the paper describing why it's not a simple calculation is too hard for you to understand, so therefore it's wrong.

Got it.
 
Surface Detail said:
The effect of GIA on sea level is roughly 0.3 mm/year. This is relatively small compared with the currently measured value of sea level rise of 3.4 mm/year. Even if the effect of GIA is out by 50%, that still only about a 5% error in the rate of change of sea level.

It's more critical to rotation speed, though, because:
1) Rock is much heavier than water, and
2) The largest movements are on land rather than at sea.

You can't just ignore it.

Anyway, where is this rotation speed data that you're referring to?
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The rotation speed data is the day length which shows no significant change.

It is necessary to know where the change is happening to allow us to consider it. It is also not going to be much of a significance compared to moving mass from the pole to the equator.
 
Threegoofs said:
So the paper describing why it's not a simple calculation is too hard for you to understand, so therefore it's wrong.

Got it.
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Well it's too hard for you to even get the actual numbers they are talking about out of. That's due to it being utterly inpeniterable. Deliberately. It should be relitively simple to explain what they are talking about and they just blather.
 
Tim the plumber said:
Well it's too hard for you to even get the actual numbers they are talking about out of. That's due to it being utterly inpeniterable. Deliberately. It should be relitively simple to explain what they are talking about and they just blather.
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Your creative spelling of "impenetrable" is perhaps an indication that the problem lies with you rather than them :lol:
 
Surface Detail said:
Your creative spelling of "impenetrable" is perhaps an indication that the problem lies with you rather than them :lol:
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So go and look at the paper and come back with your explaination of it. Should be easy for your great intelligence.
 
Tim the plumber said:
Well it's too hard for you to even get the actual numbers they are talking about out of. That's due to it being utterly inpeniterable. Deliberately. It should be relitively simple to explain what they are talking about and they just blather.
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Your excuse that you dont understand, so therefore its not important is pathetic.

The simple fact that you couldnt even do a simple search to investigate the topic more, and find quotes from the investigators, and basic explanations of the research is both pathetic and laughable.

https://www.theguardian.com/science/2015/dec/11/climate-change-longer-days-glaciers-north-south-pole

The clownage here is palpable.
 
Threegoofs said:
Your excuse that you dont understand, so therefore its not important is pathetic.

The simple fact that you couldnt even do a simple search to investigate the topic more, and find quotes from the investigators, and basic explanations of the research is both pathetic and laughable.

https://www.theguardian.com/science/2015/dec/11/climate-change-longer-days-glaciers-north-south-pole

The clownage here is palpable.
Click to expand...

Harvard University researchers have provided an answer to a long-held conundrum over how shrinking glaciers are affecting the rotation and axis of the Earth, calculating that the duration of a day has lengthened by a millisecond over the past 100 years.
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Just don't do numbers do you?

Munk factored in the impact of the end of the Ice Age 5,000 years ago, when melting over the previous 15,000 years would have helped slow the Earth’s rotation. But, surprisingly, he found that even with average sea level rises of 2mm a year during the 20th century, there was no change to the Earth’s rotation or axis beyond that caused by the Ice Age ending.
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So that means that either something is magically countering the effect or it's actually happening.
 
Threegoofs said:
Your excuse that you dont understand, so therefore its not important is pathetic.

The simple fact that you couldnt even do a simple search to investigate the topic more, and find quotes from the investigators, and basic explanations of the research is both pathetic and laughable.

https://www.theguardian.com/science/2015/dec/11/climate-change-longer-days-glaciers-north-south-pole

The clownage here is palpable.
Click to expand...
So the executive summary is something like this:

The conundrum, Munk's enigma, was that recent ice melting didn't seem to have slowed the Earth's rotation as it should after allowing for the Earth bouncing back to its more spherical shape after the end of the ice age. However, these researchers have determined that Earth took longer than previously thought to bounce back into shape and so had been spinning faster than they thought it had in the past. This means that something must have slowed it more recently, that something being the additional water from recently melting ice.

The moral of the story is that it is very difficult to separate the various effects on the Earth's rotation speed, especially those resulting from melting ice and glacial isostatic adjustment, but the Earth's rotation does now seem to be compatible with an increasing sea level.

As an aside, I note that the Earth's rotation speed has actually been increasing over the past four decades or so, as evidenced by the fact that we're getting fewer leap seconds these days:

https://en.wikipedia.org/wiki/Leap_second
 
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.
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Not even close to being correct.

1. Compute Earth's moment of inertia.

For a sphere of uniform density, I = .4 MR²
But since Earth's density is non-uniform, the correct moment of inertia factor is .3307, hence for Earth, I = .3307 MR²
Mass = 5.97e24 kg
Radius = 6371 km
therefore I = 8.02e31 kg km²

2. Compute moment of inertia for a thin shell of water 1 mm thick

Volume of 1 km x 1 km x 1 mm of water = 1000 x 1000 x .001 = 1000 m³.
Mass of 1000 m³ water = 1e6 kg

Area of Earth's oceans: 361,060,000 km²
Mass of 1mm water added to earth's oceans: 1e6 x 3.6106e8 = 3.6106e14 kg

For a thin spherical shell, I = 2/3 MR²
Here we assume that the oceans are evenly distributed across the surface, which isn't true, but it's not far wrong.
Therefore moment of inertia of 1mm water shell = 9.77e21 kg km²

Notice already: TEN orders of magnitude difference!

3. Angular momentum is conserved. Compute angular momentum L = Iω where ω is angular velocity in radians per second. For earth, ω = 2 π / 86400.
Therefore angular momentum L = 8.02e31 2 π / 86400 = 5.83e27 kg km² rad/sec.

Assuming for convenience that polar ice is perfectly axial, its angular momentum is zero. Melting the ice adds the moment of inertia of the shell to the moment of inertia to the Earth as a whole. So post-melt moment of inertia is: 8.02e31 + 9.77e21 = 8.02e31 (plus a lot of decimals) kg km². Since angular momentum is conserved, the new tiny-bit larger moment of inertia must be balanced by a new tiny-bit smaller angular velocity.
So:
Initial angular velocity: 7.242205216643040e-5 rad/sec
Final angular velocity: 7.272205215756699e-5 rad/sec
with a difference of 8.8634e-15 rad/sec

which amounts to a longer day by a whopping 10.53 microseconds (that's millionths of a second).

Is this detectable? It's just barely within measureability limits, but it is swamped by daily effects of weather (~1 order of magnitude larger), seasonal effects (~2 orders of magnitude larger) and long-term lunar effects (~3 orders of magnitude larger). So it's lost in the noise.
 
Poor Debater said:
Not even close to being correct.

1. Compute Earth's moment of inertia.

For a sphere of uniform density, I = .4 MR²
But since Earth's density is non-uniform, the correct moment of inertia factor is .3307, hence for Earth, I = .3307 MR²
Mass = 5.97e24 kg
Radius = 6371 km
therefore I = 8.02e31 kg km²

2. Compute moment of inertia for a thin shell of water 1 mm thick

Volume of 1 km x 1 km x 1 mm of water = 1000 x 1000 x .001 = 1000 m³.
Mass of 1000 m³ water = 1e6 kg

Area of Earth's oceans: 361,060,000 km²
Mass of 1mm water added to earth's oceans: 1e6 x 3.6106e8 = 3.6106e14 kg

For a thin spherical shell, I = 2/3 MR²
Here we assume that the oceans are evenly distributed across the surface, which isn't true, but it's not far wrong.
Therefore moment of inertia of 1mm water shell = 9.77e21 kg km²

Notice already: TEN orders of magnitude difference!

3. Angular momentum is conserved. Compute angular momentum L = Iω where ω is angular velocity in radians per second. For earth, ω = 2 π / 86400.
Therefore angular momentum L = 8.02e31 2 π / 86400 = 5.83e27 kg km² rad/sec.

Assuming for convenience that polar ice is perfectly axial, its angular momentum is zero. Melting the ice adds the moment of inertia of the shell to the moment of inertia to the Earth as a whole. So post-melt moment of inertia is: 8.02e31 + 9.77e21 = 8.02e31 (plus a lot of decimals) kg km². Since angular momentum is conserved, the new tiny-bit larger moment of inertia must be balanced by a new tiny-bit smaller angular velocity.
So:
Initial angular velocity: 7.242205216643040e-5 rad/sec
Final angular velocity: 7.272205215756699e-5 rad/sec
with a difference of 8.8634e-15 rad/sec

which amounts to a longer day by a whopping 10.53 microseconds (that's millionths of a second).

Is this detectable? It's just barely within measureability limits, but it is swamped by daily effects of weather (~1 order of magnitude larger), seasonal effects (~2 orders of magnitude larger) and long-term lunar effects (~3 orders of magnitude larger). So it's lost in the noise.
Click to expand...

Which is very similar to the result I got because I worked out the value for a year. You get 3.7 thousanths of a second per year for a 1mm sea level rise.

Swamped dy to day but over a year it's clear and over a decade it's massively more than the other factors. Thanks.
 
Tim the plumber said:
Which is very similar to the result I got because I worked out the value for a year. You get 3.7 thousanths of a second per year for a 1mm sea level rise.

Swamped dy to day but over a year it's clear and over a decade it's massively more than the other factors. Thanks.
Click to expand...

It may seem like a fun mathematical exercise, but for anyone actually in a field of science such as meteorology, the real world is nowhere close to that simple.

Weather, for instance, is not an independent external variable here; melting polar ice will bring about significant changes to the weather and while some areas will get hotter and/or drier whilst others get colder and/or wetter, generally we will see more and bigger superstorms than we have at any point in recorded history (most certainly more numerous and powerful since the advent of radar and modern recordings). Those very same superstorms and other effects will nudge planetary tilt and rotation differently than the mass and volume of re-distributed water.

There's also post-glacial rebound to consider from deglaciated land such as Antarctica and Greenland -- where thick ice sheets had been over land, they had weighted the land down. Remember that the crust sort of 'floats' on the mantle; significant mass resting on it (such as massive continental ice sheets) put a sinking pressure on that part of the crust. If that mass that had pressed that continent down for a long time suddenly vanishes, the land will spring upward with the mass no longer resting on it, and it will be in uneven jolts -- earthquakes. Prior to a recent major uptick attributable to fracking, a significant portion of away-from-tectonic-plate-edges earthquakes in places like North America have been due to ongoing post-glacial rebound. While such earthquakes tend to be minor, they too will have some effect on planetary spin and tilt, as will the re-settlement of the magma below the crust adjusting to lower pressure due to less weight squeezing it.

There are endless chains of complex changes on any particular aspect, such as the rate of planetary spin, that result even from a single 'event' such as global warming. Insisting there would be one and only one resulting factor is rather ridiculous.
 
DirtyRat said:
It may seem like a fun mathematical exercise, but for anyone actually in a field of science such as meteorology, the real world is nowhere close to that simple.

Weather, for instance, is not an independent external variable here; melting polar ice will bring about significant changes to the weather and while some areas will get hotter and/or drier whilst others get colder and/or wetter, generally we will see more and bigger superstorms than we have at any point in recorded history (most certainly more numerous and powerful since the advent of radar and modern recordings). Those very same superstorms and other effects will nudge planetary tilt and rotation differently than the mass and volume of re-distributed water.

There's also post-glacial rebound to consider from deglaciated land such as Antarctica and Greenland -- where thick ice sheets had been over land, they had weighted the land down. Remember that the crust sort of 'floats' on the mantle; significant mass resting on it (such as massive continental ice sheets) put a sinking pressure on that part of the crust. If that mass that had pressed that continent down for a long time suddenly vanishes, the land will spring upward with the mass no longer resting on it, and it will be in uneven jolts -- earthquakes. Prior to a recent major uptick attributable to fracking, a significant portion of away-from-tectonic-plate-edges earthquakes in places like North America have been due to ongoing post-glacial rebound. While such earthquakes tend to be minor, they too will have some effect on planetary spin and tilt, as will the re-settlement of the magma below the crust adjusting to lower pressure due to less weight squeezing it.

There are endless chains of complex changes on any particular aspect, such as the rate of planetary spin, that result even from a single 'event' such as global warming. Insisting there would be one and only one resulting factor is rather ridiculous.
Click to expand...

Drivel.

The changes to weather will balance out. There may be some temporary noise in the system due to this but there will be no long term effect on day length.

The movement of land at the pole where the ice is supposed to be melting from will have very little effect upon spin rate due to it's location, it's vertical movement parallel to the axis of rotation and the fact that it is not moving far as opposed to the 6,000+km that the water is moving.

The point is that the excusses that are given for the lack of observed changes to the day/year length do not add up. The idea that we have been able to measure the mass changes/ice melt of Greenland by the deviation of a satellite's path going over it is just silly. There are, in that case, any number of factors which will give wrong results.
 
Tim the plumber said:
Drivel.

The changes to weather will balance out. There may be some temporary noise in the system due to this but there will be no long term effect on day length.
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FACT. Feedback between variables creates very difficult-to-predict chaos. You reject scientific discipline and realities, don't act surprised that no one gives your alchemy the same respect as actually informed, supported and educated analysis. And "supported" doesn't mean selectively disregarding established data, knowledge and science that doesn't fit with your premise.
 
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