Length of day increase and sea level rise linked

Via press release today from the University of Alberta.

The days are getting longer

Scientists reveal that the rotation of Earth’s core holds a clue to understanding global sea-level rise

Scientists are studying past changes in sea level in order to make accurate future predictions of this consequence of climate change, and they’re looking down to Earth’s core to do so. “In order to fully understand the sea-level change that has occurred in the past century, we need to understand the dynamics of the flow in Earth’s core” says Mathieu Dumberry, a professor in physics at the University of Alberta.

Mathieu Dumberry from the University of Alberta is one of only a few people in the world investigating changes in Earth rotation. CREDIT John Ulan for the University of Alberta

Mathieu Dumberry from the University of Alberta is one of only a few people in the world investigating changes in Earth rotation. CREDIT John Ulan for the University of Alberta

The connection is through the change in the speed of Earth’s rotation. Melt water from glaciers not only causes sea-level rise, but also shifts mass from the pole to the equator, which slows down the rotation. (Picture the Earth as a spinning figure skater. The skater moves his or her arms in to spin more quickly or out to slow down.) The gravity pull from the Moon also contributes to the slow down, acting a little like a leaver break. However, the combination of these effects is not enough to explain the observations of the slowing down of Earth’s rotation: a contribution from Earth’s core must be added.

One of only a few people in the world investigating changes in Earth rotation, Dumberry contributed his expertise on Earth’s core-mantle coupling to the study. “Over the past 3000 years, the core of the Earth has been speeding up a little, and the mantle-crust on which we stand is slowing down.” As a consequence of Earth rotating more slowly, the length of our days is slowly increasing. In fact, a century from now, the length of a day will increase by 1.7 milliseconds. This may not seem like much, but Dumberry notes that this is a cumulative effect that adds up over time.

Based on their work reconciling these discrepancies, the scientists involved in the study are confident in predicting sea level to the end of the 21st century. “This can help to better prepare coastal towns, for example, to cope with climate change,” says Dumberry. “We’re talking billions of dollars of infrastructure here.” Dumberry notes that this study serves as a stimulus for more work to continue investigating the deep interior of our planet.

The findings, “Reconciling past changes in Earth’s rotation with 20th century global sea-level rise: Resolving Munk’s enigma,” were published in the December 11, 2015 issue of the journalScience Advances.

With 12 climate change-related centres and institutes and 24 climate change-related Canada Research Chairs, the University of Alberta is committed to researching the causes and effects of climate change. Researchers study past climate changes to better predict future changes.


120 thoughts on “Length of day increase and sea level rise linked

  1. I’m not sure how this is supposed to work. They reference the “poles”, but the north pole shouldn’t have any impact, because the mass of ice already displaces water, so it should have no impact on rotation. Interesting to note that this change in rotation has occured “since the Industrial Revolution”, i.e., since the end of the Little Ice Age. Shouldn’t we instead be seeing an increase in the length of the day for only the past 100 years?

    • They’re specifically talking about terrestrial ice. But what model for mass loss and mass redistribution are they using, how did they filter out effects from changes in ocean circulation and atmospheric circulation, and what is their certainty in the measurements they actually did take? Also, the Earth’s rotation has been slowing since the moon has been orbiting around the planet. Smells of pseudoscience to me.

      • Furthermore, redistribution of mass within the lower crust and mantle needs filtered as does the isostatic movement of the crust.

      • Terrestrial glaciers are often well above sea level, melting them would cause mass to get lower in elevation.

    • actually it will….it has to do with polar moment of inertia…it’s affected by the distance from the centroidal axis. the ice is actually above the level of the water…….so it would create a larger polar moment of inertia.

      • In which case, as the ice melts there should be an increase in rotational speed, not decrease. I’m going to guess that to within measurement error you can’t detect the effect of melting all the sea-borne ice at the north pole, since 90% of the mass is “below” sea level, and since it’s relatively close to the axis of rotation the effect is smaller still.

      • My grandfather who was an astronomer working at Mt. Wilson studied the earth’s rotation, 100 years ago. This is not surprising news, the earth has been slowing down its rotation since it was born. And the moon was a lot closer, too!

      • But before doing that: There’s another way of checking it, because if the radius of the Earth increases, because sea level is rising, then immediately the Earth’s rate of rotation would slow down. That is a physical law, right? You have it in figure-skating: when they rotate very fast, the arms are close to the body; and then when they increase the radius, by putting out their arms, they stop by themselves. So you can look at the rotation and the same comes up: Yes, it might be 1.1 mm per year, but absolutely not more. It could be less, because there could be other factors affecting the Earth, but it certainly could not be more. Absolutely not! Again, it’s a matter of physics. So, we have this 1 mm per year up to 1930, by observation, and we have it by rotation recording. So we go with those two. They go up and down, but there’s no trend in it; it was up until 1930, and then down again. There’s no trend, absolutely no trend.
        Dr. Nils-Axel Mörner in an interview with Gregory Murphy for EIR (Executive Intelligence Review). In June, 2007. But this is new research and reasoning?

      • The length of the day is a function of the distance between the earth and the moon. After the moon collided with the earth, the earth day was about 5 hours. As time passed the distance between the earth and the moon has increased and so has in proportion the earth’s day. At some point in the distance future (millions of years from now) the earth day will be 25 hours. All these other claimed factors are minor or rubbish.

    • The core is speeding up and the mantle is slowing down? what if they part company? is Hapgood becoming fashionable?

      • The text breaks down sea level rise as follows;
        “melting of glaciers (0.7 ± 0.1 mm/year, as noted previously) (18), thermal expansion (0.4 ± 0.1 mm/year) (10), and net anthropogenic storage of water on land (−0.11 ± 0.05 mm/year)”
        Presumably this last input-which comes from Church-relates to reservoir storage rather than that coming from aquifers.

      • climatereason December 14, 2015 at 9:10 am
        I find the following interesting’
        By picking 1990s as a cut off date they exclude the worst of the “controversial” date
        We limit our discussion to estimates based on observations up to 1990 to avoid signals associated with the onset of major polar ice mass flux and the acceleration of mountain glacier melting beginning in the early 1990s and continuing to the present (7–10).

  2. 1.7 milliseconds a year adds up over time.
    Yes it does, and I’ve just invested several years of my extra time from longer days typing this comment.
    The question now is – dare I commit any more time reserves contemplating the wisdom or otherwise of my action?

    • “1.7 milliseconds a year adds up over time.”
      I think I’ve discovered a link between length of day increase and my stock portfolio. 😉

      • Reminds me of the old saw about the student at the back of the room waving frantically: “Professor! When did you say the sun would burn out?” He responds: “I said in about four billion years.” “Oh, that’s a relief,” says the student, “I thought you said four million years.”

      • At that rate, in a billion years a day will be 28.7 hours long. But that rate of change will slow down slightly as the moon recedes.
        And then a year will only 305.4 days long compared to 365.24 now. I can’t imagine how Earth’s biosphere will adapt to such radical change since it apparently can’t adapt to 1 C warmer than present 100 years from now without apocalyptic implications.

    • We should spend about 100 billion per year over the next 3000 years to help poor nations adapt to this catastrophic global rotation change. Many moths will be at risk because of the longer days, and corresponding earlier springs. Global devastation is the only possible result.

  3. The last paragraph of the press release is a total non sequitur. Although the press release drafter mentions “climate change” in the first sentence, there is nothing in the remainder of the release having to do with climate change. Are people really so clueless that they’ll refer to any change in the Earth as climate change? It truly makes one wonder.

    • Climate change had to be added somewhere to get funding for an otherwise less politically interesting paper. Just as the cost of infrastructure on the coast was purely there for monetizing the paper.

    • I don’t think they are clueless, more like they are playing to the current rules. If you don’t mention climate change you don’t get the grant money

    • The two lines that reveal the real purpose of this release:
      “One of only a few people in the world investigating changes in Earth rotation, Dumberry…”
      “Dumberry notes that this study serves as a stimulus for more work to continue investigating the deep interior of our planet.”
      Dumberry doesn’t have the strength in numbers to lobby for more money so he resorts to the scare tactic of rising seal levels. Sad.

    • Well, its the inverted pyramid of traditional journalism turned upside down, as all things are these days.
      In the old days, you put the important stuff first, then less important stuff, down to the totally unimportant stuff. You did this just in case a salesman had sold another underwear ad, and they need to cut your worthy prose (don’t tell a working journalist this, as they don’t like being reminded that they only have a job to keep the underwear ads from running together).
      Now its: headline, which usually misrepresents the lede (i.e., top of story), which sometimes contradicts the details in the story, which has no reference anyway to the scientific paper (which the journalist – really an unpaid intern) didn’t read. All this has little to do with the actual data, which might, if only by accident, made it into the appendix.
      So basically its now: unpaid intern rewriting a press release from a Green Blob organization which trumpets the science of a paper that barely says what they think it says, hoping nobody checks (which we do, which is why global warming is so far down the list of things that people actually care about).

    • I was thinking along those lines. Why is sea level rise linked as the reason for changes in the length of day? Don’t subduction earthquakes reduce the length of day? And don’t volcanoes also affect the length of day? How can filter out the frequent microsecond adjustments that earthquakes and volcanoes cause from sea level rise adjustments?

  4. “In fact, a century from now, the length of a day will increase by 1.7 milliseconds. This may not seem like much, but Dumberry notes that this is a cumulative effect that adds up over time.”
    So, in a century we are talking about .17 seconds. And the relevance to Global Warming is?

    • Ah, but they are – just read the article. Melt water from the polar ice is moving to the equator, which slows the rotation.
      Of course, that only works when you use the models to “prove” that the total polar ice mass is decreasing, rather than believing your lying observations that tell you it is increasing. (Before the usual troll runs into the room – two poles, remember?)

    • Well you see, CO2 weighs more therefore the mass of the earth’s atmosphere is increasing and slowing its rotation rate. Now that didn’t take long did it?

    • Carbon was in the ground, now CO2 is in the atmosphere. Obviously the atmosphere is further from the axis of rotation than is the ground. Ergo, raising carbon from underground to the atmosphere will cause the earth’s rate of spin to slow. It’s worse than we thought.

  5. This is just some attempt at time warp: a means of stretching out the date by which even the most greedy, and/or unintelligent of Climate Scientists supporting CAGW and Climate Change will have to admit that CO2 levels has little if any relevance! They must keep that gravy train on the tracks for as long as possible! Look at the number of Research Programmes listed above, simple for Alberta Canada!

  6. “… the core of the Earth has been speeding up a little, and the mantle-crust on which we stand is slowing down.”
    Won’t that cause increased friction/heat/volcanic activity/tectonic activity/”global warming”?

  7. 400 million years ago, there were 400 days in the year. The Earth’s rotational speed has been slowing down for hundreds of millions of years

    • What, you want to introduce actual long-term data to the discussion?
      But they were doing so well with a much (much, much) smaller subset of three thousand years.
      Oh, sorry, I though they were giving us an example about “start and end point bias”.
      You seem to be talking about science.
      Never mind…
      (Nice pose on the guy, though. Very thoughtful and genius-like).

  8. At first glance, I thought “a geology study”, we can take a break from Global Warming for a bit.
    No matter what your field of study, it is CAGW all the way down.
    One university, 12 climate change centers, 24 Research Chairs. Is there any possibility they still have room to do science?

    • “In fact, a century from now, the length of a day will increase by 1.7 milliseconds”
      Do you get the feeling that this guy is not into error analysis?

      • It could be he is not really into analysis! I’d say by eyeballing the above graph that the peak-to-peak variation in earth’s length of day is about 2 milliseconds.

    • Ironic, isn’t it: the Alberta oil patch is basically drying up, which means the NDP government is broke, which means that taxpayers are actually paying more and more for this crap, when you add in all the interest payments.

  9. This is interesting since the core is where the magnetic field is generated and anything that links the core to climate can help explain links to cosmogenic isotopes. Earth and Sun’s magnetic field help deflect cosmic rays. Earth’s magnetic field also deflects the solar wind and so all in all its pretty important. Earth’s magnetic field has recently gone walk about and is weakening.

  10. Of course, stuff like this only feeds into the belief system of those who believe the earth is only 6,000 years old, you know.

  11. Nobody denies that the sea levels are rising. They’ve been rising for something like 400 years, with no increase in rate over the last few decades.
    The question is, how much of this rise is due to CO2. The answer to that question is: Not much.

  12. So why is the core speeding up?
    The darn thing is rather heavy, and speeding it up would require a LOT of energy, not to mention some sort of force acting on it.

    • You could calculate it: core density 8 tonnes/cubic M, acceleration to 1.7 milliseconds per day per 100yrs.
      BTW, this must go down as a negative feedback. If signicant, it would be a good post for an engineer or physicist to put together. After all, it is due to climate melting ice. I’m an engineer, but having sampled 9 decades of life, I prefer to pass this off.

  13. … Study past climate change to predict future cc. Is this old fashioned approach going to be permitted by the Synod of Climate Bishop’s?
    Pre-postnormal geology used the principle that the present was the key to the past. The Synod outlawed this with their ruling that we got the past wrong and it needs to be continually adjusted as needed for it to be fit for purpose.
    As Mark Steyn noted at the recent Senate hearing on climate dogma or data in reference to ‘adjustments’ to climate data, predicting what’s going to have happened in 1950 is more difficult than diagnosing the weather in 2100 apparently.
    If the authors of this study are correct about how they will proceed, then I say kudos, with the caveat that they should be aware that their findings will be quite different than what they would have got had they done their work in 1950.

  14. I have a theory that Gaia is slowing down due to the effect of wind turbines drawing too much energy from the air. I propose that Big Fossil Fuels put their squillions spent on funding climate sceptics into researching just how many bird-mincers the Planet can take before the tipping point is reached and rotation stops almost entirely. Our grandchildren may never know what a day is!
    Just in case, /sarc.

  15. But but but … didn’t we just hear that Antarctica is actually GAINING ice? That means that only the NH is slowing down – the SH is speeding up!
    Sheesh, somebody call Hank Johnson! He doesn’t need to worry about Guam capsizing. With the SH trying to go faster than the NH earth is going to fracture at the equator, split open and all our water will drain into it leaving Guam safely sitting upright on the muddy bottom. We’re all doooomed!

    • http://www.iers.org/IERS/EN/Science/EarthRotation/EarthRotation.html

      Measuring the irregularities of the Earth’s rotation
      The variability of the earth-rotation vector relative to the body of the planet or in inertial space is caused by the gravitational torque exerted by the Moon, Sun and planets, displacements of matter in different parts of the planet and other excitation mechanisms. The observed oscillations can be interpreted in terms of mantle elasticity, earth flattening, structure and properties of the core-mantle boundary, rheology of the core, underground water, oceanic variability, and atmospheric variability on time scales of weather or climate. The understanding of the coupling between the various layers of our planet is also a key aspect of this research.

  16. Given past glacial periods and interglacials, how much did the Earth speed up at the end of the a glacial and how much did it slow down when the ice returned? When we go back into a glacial period, what will the 1.7 millisecond be worth?

  17. Dr. Nils-Axel Moerner had this covered years ago in the 1992 Journal of Coastal Research:
    Home > Vol 8, No 4 (1992) > Morner
    Sea-Level Changes and Earth’s Rate of Rotation
    Nils-Axel Morner
    The mean global sea-level changes today and in the near past (and by that also in the near future) have not been able to establish in a satisfactory way, either by mathematical treatments of tide-gauge data, by geophysical modelling or by geological considerations. We here propose 8 new means of studying global mean sea level; viz. changes in the Earth’s rate of rotation (the variations in the length of the day). Any global change in sea level must be seen in the Earth’s rate of rotation as this is a direct function of any change in its radius. The decadal changes in rotation swing around a sinusoidal, about century long, mean trend that might represent such a global sea level factor. This factor is consistent with a sea level rise in the order of 11 cm in 100 years (which is a fraction of often claimed values for the hypothetical greenhouse generated sea level rise today and in the near future). This can be taken as a measure of the maximum possible rise in global mean sea level during the last 150 years. It can, however, not be excluded that it represents the interchange of angular momentum with a more slowly moving oceanic intermediate or bottom water currents. If so, there would be no significant global rise in mean sea level during the last 150 years. The recording of LOD changes is a powerful tool for monitoring and predicting global sea level changes.

  18. He says the core is speeding up while the mantle is slowing down. I’m trying to digest that, but I think I need some bicarbonate. So my first question would be, and where is the energy that would be needed to “speed up” the core coming from? Like plate tectonics, I have to constantly ask, WHERE is the power source that is forcing a 50 mile thick plate to sink and go under another 50 mile think plate? And now I have to ask where is the power source for “spinning up” the core coming from? There seems to be so many dynamic motions on going, and there appears to be no increase in energy available to cause them.

    • This article has fascinated me for years now.
      From above mentioned article:
      2.1 SUMMARY
      A phenomenon of close correlation between the main climatic index dT and geophysical index (-LOD) still remains an intricate puzzle of geophysics. Another challenging puzzle is the observable 6-year lag between the detrended run of dT and -LOD. Taking into account this lag, the LOD observations can be used as a predictor of the future climatic trends. Even without a mechanism for a causal relationship between the detrended climatic (dT) and geophysical (LOD) indices, the phenomenon of their close similarity for the last 140 years makes LOD a convenient tool to predict the global temperature anomaly (dT) for at least 6 years ahead.
      Willis? Would you be interested to take a look? You would make me so happy!
      Or is there a geophysicist in the room who would like to do it?

  19. Just what is a “leaver break”? Presumably the author meant “lever brake” but I’m not even sure I know what that is in comparison to any other type of brake. I can’t imagine they’re trying to say that the earth has handlebars!

  20. But won’t the number of us who’ll be spinning in our graves in 100 years offset this? I don’t believe the paper took that into account.

  21. There is a very strong correlation between changes in the Earth rotation and El Niño.
    One theory says that changes in the Earth rotation weaken the trade winds and cause the conditions that cause an El Niño.
    The other theory is that El Niño conditions weaken the trade winds that cause a change in the Earth rotation.
    I like the second one better.

  22. This is another piece of alarmist garbage. Yes, the Earth’s rotation may slow by 1.7 milliseconds per century, but at best this is merely an academic curiosity. The implication in the authors comment “these effects add up” is one of inexorability. What he (conveniently) forgot to mention is that unlike the rotational loss due to tidal effects, this effect does not loose angular momentum which must remain constant.
    All that happens is that some mass is rotating further from the axis and this must result in a lower angular velocity in order for the angular momentum to remain constant. At the point when sea levels begin to decline again. the whole show reverses and rotation rate will increase.

    • A change of 1.7 msec/century in the length of the day is a change of 17 usec/year, or a change of roughly 6 msec in the length of the year from one year to the next. This isn’t enough to matter for ordinary life, but I estimate that GPS systems would drift by a couple of metres a year if this weren’t accounted for. (I just woke up so this could be completely wrong.) It’s partly because of this effect that since the current definition of the second was adopted, NO day has been 86,400 seconds long. It’s also because of changes in the LOD that we have leap seconds to deal with, horrible things that they are.

  23. Earth’s rotation slow by 1.7 milliseconds per century so that’s why I’m always late for things
    aint science wonderful !!

  24. From a discussion on the CBC article: Peltier is rather unimpressed…
    “But the mystery may not be quite resolved, according to some. William Richard Peltier, a professor of physics at the University of Toronto, takes issue with some of the paper’s key points. Peltier was not involved with this paper, but is familiar with much of the work that went into it — Mitrovica was one of his doctoral students, and some of Peltier’s own work was incorporated into Munk’s original calculations.
    Peltier’s main issue with the argument in the paper has to do with the new viscosity model — the model of the way the Earth flows — that the authors used to help account for the ice age effect. Previous research has suggested that this model does not match up with observed data on the way the Earth’s geology actually behaves, Peltier said. In essence, he claims, this aspect of the paper is “absolutely incorrect.”
    Peltier was one of the key authors with Clark and Farrell of the seminal paper in 1978 titled global changes in post glacial sea levels: a numerical calculation.
    I guess the young gun is visibly trying to make a name for himself and thus dabbling in climate related stuff… since the viscosity of money flow to climate related subjects is decreasing…

    • As long as he doesn’t read it. This one qualifies for the “wall of shame”.
      The picture looks at first glance like Pee Wee and Globie.

  25. Obviously, this article is all about “spin”.
    I could not help it. Its one of those mornings. — Eugene WR Gallun

    • Eugene, we both know this isn’t about scoring points, but that was worth 100 for the pun alone, in my book.
      Let alone it was deadly accurate…
      Steve L

  26. if I fart that would actually change the earth rotation….so what….it only leaves the same smell in the room as this article

  27. I think the very last paragraph really tells you all you need to know
    “With 12 climate change-related centres and institutes and 24 climate change-related Canada Research Chairs, the University of Alberta is committed to researching the causes and effects of climate change. Researchers study past climate changes to better predict future changes.”
    So, the only way this guy could get funding at the UofA was to use a ridiculous AGW tie in.

    • When you have a hammer, its amazing how many things look like nails.
      Amazing that organizations designed to find stuff actually find stuff. Even if it isn’t always the stuff they are actually looking for…

  28. Here is my question. Now that NASA has shown that the ice in Antarctica is growing; and knowing that ice in the arctic is floating (i.e. already displacing water, so not changing the mass distribution), only Greenland is at issue here. Does this change the results of this modeled ‘study’?

    • Sorry, he used: “this consequence of climate change”, and the politically correct definition of climate change implies anthropogenic causation. Of course, there is also the implication of linear warming in the PC definition, which is the only scenario under which “this consequence” (however consequential it might be) could possibly occur.

  29. Sea level rise is more less constant, due to river silt deposits oceans and volcanic activity. Basically for every cubic meter of mud deposited from river into ocean, sea level rises as there would be one cubic meter of water more. Same with volcanic activity, for every cubic meter of magma from underwater volcano there is sea level rise of one cubic meter water.
    So there is amount of sea level rise which is constant and normal. Regardless Earth ice sheets and spin rate conditions.

    • You didn’t mention sublimation (settling and sinking) of the coastal areas as a contributor to SLR statistics.

  30. An aeonic time scale more like. isn’t it fun to split hairs over insignificant scientologic meanderings?

  31. hmmm who cares if the day is 1.7 milliseconds longer or if it was 1.7 minutes longer, or even shorter. I understand it would change the weather in the short term. But in the years, decades, centuries time frame on a global scale wouldn’t that extra time be spent equally in day and night time (and all other times) resulting in net ZERO. IOW 365 day orbiting the sun is the same wither the earth rotates 365 times or 364 times when it comes to how much heat is absorbed\released.
    Now if they had a study saying that this faster \slower spinning resulted in more\less cloud cover or something

  32. From the article above:
    Melt water from glaciers not only causes sea-level rise, but also shifts mass from the pole to the equator, which slows down the rotation.
    While here we learn:
    When polar ice caps melt, they remove weight off underlying rock, which then rebounds upward. This makes the poles less flat and the planet more round overall. This should in turn cause Earth to tilt a bit and spin more quickly.
    Slower, faster? My head is spinning

  33. I don’t see how this one is so all-fired innovative. The original discovery was made by “Axe” Moerner. All that is added to that discovery, here, is a bit of meltwater.

  34. ==========
    “Melt water from glaciers not only causes sea-level rise, but also shifts mass from the pole to the equator, which slows down the rotation.”
    But that hasn’t been happening throughout the entire “global warming” era:

    It is interesting to note that the present overall trend of LOD shown in this figure is decreasing, which is the reverse of secular increase of LOD due to tidal dissipation. This is ascribed to certain geophysical processes in the Earth’s core and mantle, such as geodynamo. Recent fast retreat of glaciers might be related as well.”
    –Sung-Ho Na, Earth Rotation – Basic Theory and Features

    I commented on the trend last year:
    * * * * * * * * * *
    Actually, the fast retreat of glaciers should increase the length of day, since their weight as liquid would be redistributed relatively evenly, with most of the weight shifting to lower latitudes, as with the hypothetical melting of Antarctica and Greenland. The result would be similar to a figure skater extending her arms during a pirouette to slow her rate of spin.
    Perhaps Antarctica has been putting on weight for the last 30 years?
    * * * * * * * * * * * *

  35. Um
    “With 12 climate change-related centres and institutes and 24 climate change-related Canada Research Chairs, the University of Alberta is committed to researching the causes and effects of climate change. Researchers study past climate changes to better predict future changes.”

  36. After reading the above on the possible impact of rising oceans in the low latitudes maybe affecting the spinning rate of the earth I am left wondering if the net accumulation of ice measured in billion of tonnes annually in Antarctica possibly increasing the mass of the southern hemisphere- is being wholly or partially counter- balanced by the hundreds of millions of tonnes of iron ore and coal being mined and exported annually from the southern hemisphere nations of Brazil and Australia to the northern hemisphere nations of China India and Japan?

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