The shifting of mass and consequent sea level rise due to groundwater withdrawal has caused the Earth’s rotational pole to wander nearly a meter in two decades
AMERICAN GEOPHYSICAL UNION
American Geophysical Union
15 June 2023
Release No. 23-25
For Immediate Release
This press release is available online at: https://news.agu.org/press-release/weve-pumped-so-much-groundwater-that-weve-nudged-the-earths-spin
AGU press contact:
Rebecca Dzombak, news@agu.org (UTC-4 hours)
Contact information for the researchers:
Ki-Weon Seo, Seoul National University, seokiweon@snu.ac.kr (UTC+9 hours)
WASHINGTON — By pumping water out of the ground and moving it elsewhere, humans have shifted such a large mass of water that the Earth tilted nearly 80 centimeters (31.5 inches) east between 1993 and 2010 alone, according to a new study published in Geophysical Research Letters, AGU’s journal for short-format, high-impact research with implications spanning the Earth and space sciences.
Based on climate models, scientists previously estimated humans pumped 2,150 gigatons of groundwater, equivalent to more than 6 millimeters (0.24 inches) of sea level rise, from 1993 to 2010. But validating that estimate is difficult.
One approach lies with the Earth’s rotational pole, which is the point around which the planet rotates. It moves during a process called polar motion, which is when the position of the Earth’s rotational pole varies relative to the crust. The distribution of water on the planet affects how mass is distributed. Like adding a tiny bit of weight to a spinning top, the Earth spins a little differently as water is moved around.
“Earth’s rotational pole actually changes a lot,” said Ki-Weon Seo, a geophysicist at Seoul National University who led the study. “Our study shows that among climate-related causes, the redistribution of groundwater actually has the largest impact on the drift of the rotational pole.”
Water’s ability to change the Earth’s rotation was discovered in 2016, and until now, the specific contribution of groundwater to these rotational changes was unexplored. In the new study, researchers modeled the observed changes in the drift of Earth’s rotational pole and the movement of water — first, with only ice sheets and glaciers considered, and then adding in different scenarios of groundwater redistribution.
The model only matched the observed polar drift once the researchers included 2150 gigatons of groundwater redistribution. Without it, the model was off by 78.5 centimeters (31 inches), or 4.3 centimeters (1.7 inches) of drift per year.
“I’m very glad to find the unexplained cause of the rotation pole drift,” Seo said. “On the other hand, as a resident of Earth and a father, I’m concerned and surprised to see that pumping groundwater is another source of sea-level rise.”
“This is a nice contribution and an important documentation for sure,” said Surendra Adhikari, a research scientist at the Jet Propulsion Laboratory who was not involved in this study. Adhikari published the 2016 paper on water redistribution impacting rotational drift. “They’ve quantified the role of groundwater pumping on polar motion, and it’s pretty significant.”
The location of the groundwater matters for how much it could change polar drift; redistributing water from the midlatitudes has a larger impact on the rotational pole. During the study period, the most water was redistributed in western North America and northwestern India, both at midlatitudes.
Countries’ attempts to slow groundwater depletion rates, especially in those sensitive regions, could theoretically alter the change in drift, but only if such conservation approaches are sustained for decades, Seo said.
The rotational pole normally changes by several meters within about a year, so changes due to groundwater pumping don’t run the risk of shifting seasons. But on geologic time scales, polar drift can have an impact on climate, Adhikari said.
The next step for this research could be looking to the past.
“Observing changes in Earth’s rotational pole is useful for understanding continent-scale water storage variations,” Seo said. “Polar motion data are available from as early as the late 19th century. So, we can potentially use those data to understand continental water storage variations during the last 100 years. Were there any hydrological regime changes resulting from the warming climate? Polar motion could hold the answer.”
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AGU (www.agu.org) is a global community supporting more than half a million advocates and professionals in Earth and space sciences. Through broad and inclusive partnerships, AGU aims to advance discovery and solution science that accelerate knowledge and create solutions that are ethical, unbiased and respectful of communities and their values. Our programs include serving as a scholarly publisher, convening virtual and in-person events and providing career support. We live our values in everything we do, such as our net zero energy renovated building in Washington, D.C. and our Ethics and Equity Center, which fosters a diverse and inclusive geoscience community to ensure responsible conduct.
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Notes for journalists:
This study is published in Geophysical Research Letters, a fully open-access journal. View and download a pdf of the study here.
Paper title:
“Drift of the Earth’s pole confirms groundwater depletion as a significant contributor to global sea level rise 1993-2010”
Authors:
- Ki-Weon Seo (corresponding author), Center for Educational Research and Department of Earth Science Education, Seoul National University, Seoul, Republic of Korea
- Jae-Seung Kim, Kookhyoun Youm, Department of Earth Science Education, Seoul National University, Seoul, Republic of Korea
- Dongryeol Ryu, Department of Infrastructure Engineering, The University of Melbourne, Parkville, Australia
- Jooyoung Eom, Department of Earth Science Education, Kyungpook National University, Daegu, Republic of Korea
- Taewhan Jeon, Center for Educational Research, Seoul National University, Seoul, Republic of Korea
- Jianli Chen, Department of Land Surveying and Geo-informatics, and Research Institute for Land and Space, Hong Kong Polytechnic University, Hong Kong
- Clark Wilson, Department of Geological Sciences, and Center for Space Research, University of Texas at Austin, Austin, TX, USA
JOURNAL
Geophysical Research Letters
DOI
ARTICLE TITLE
“Drift of the Earth’s pole confirms groundwater depletion as a significant contributor to global sea level rise 1993-2010”
ARTICLE PUBLICATION DATE
15-Jun-2023
I tell you, sonny, it’s turtles (models) all the way down!
its not like you can do controlled experiments with ground water removal.
go empty the great lakes and see if it changes anything.
How do we know the earth won’t tip over? We ate so close to a climate tipping point, this could be the final straw. Next time you pee into the ocean, the poles could flip.
Tipping can be a problem. All that wobbling may by why Brandon keeps falling down.
“… the model was off by … 4.3 centimeters (1.7 inches) of drift per year.”
I note in passing that value is very near the average annual amount of continental drift, but I’m sure they took that into account in their study.
The mid Atlantic spread rate is 2-5cm/year depending on latitude. That alone, not groundwater relocation, accounts for the slight wobble.
And, in most places groundwater is replenished else wells would dry up and need to be dug deeper. Most don’t.
And when groundwater is pumped it either evaporates and returns as rain, or makes it directly to the sea where there is no mass redistribution.
How on earth did this model nonsense make it past peer review?
Our well in central India had multiple pump platforms as water level went up and down annually by 45 feet
I looked several times, and could not find any recharge estimates to off set the pumping estimates. GIGO model ??
” … but I’m sure they took that into account in their study ”
God save the queen, Mike!
Variations on this method of trying to panic people have existed for longer than you may think.
A reasonable starting point for anyone who wants to go down the “Pole Shift” rabbit hole :
https://en.wikipedia.org/wiki/Cataclysmic_pole_shift_hypothesis
Yeah, nah, the pole movement is accelerating as part of the reversal that’s coming along with the galactic electromagnetic sheet reversal – a galactic-scale manifestation of the Parker instability affecting all rotating electromagnetic fields.
Both poles are on track to meet, horseshoe-magnet style, in the Bay of Bengal.
Ben Davidson is the expert in this field, there’s a quick summary here – https://www.youtube.com/watch?v=j635Cv2aOlA&t=0s – 16m 45s.
Perhaps the Maya’ calendar was only off by a couple of decades.
Indeed.
It was past changes to calendars that throw out the comparison of Mayan and Gregorian calendars
“Based on climate models”…
There you have it.
Paging Hank Johnson…
. . . heard that he’s now living on the east side of Guam to help stabilize the place.
Correct me if I am wrong but the earths crust floats on a sea of lava. How can their model predict the movement on the lava when they clearly don’t have a model of the lava/crust interface? The bottom side of the crust is similar to the top and may go deeper into the lava in spots than in other areas. The lava also isn’t consistent in its flow as proven by the magnetic north moving around. I rate this a 10 on the BS scale.
Yes this study is right off the BS scale .
How much water is there in the oceans which moves with the tides which are moved by the sun and the moon.
If ground water is not replenished cities will run out of water and what about the hydro and irrigation dams on many rivers that the greens hate .
We have 8 hydro dams on the Waikato River plus storage gates from Lake Taupo so next week some one will write a study that the North Island is going to tip over or some such nonsense because we have had so much rain and its all stored behind these dams and its unprecedented.
I rate this a 10 on the BS scale.
Make that 11 !
With extra cowbells
You are wrong, there is no “sea of lava” below the crust. The closest continuous fluid part of the inner earth is the molten outer core below the mantle approximately halfway to earth centre.
Actually you are wrong. There is indeed a sea of magma located beneath the entire crust of the earth, which magma is molten rock which gets relabeled as “lava” only when it reaches the surface of the earth in an eruption event – magma is same material as lava.
No there is no molten magma all over, read a textbook on geology and don’t invent your own science. Sheesh.
https://en.wikipedia.org/wiki/Partial_melting
Red indicates where there is actual magma generation
Yes – this study fails to account for plate tectonics in which entire continental plates (the mass of which fantastically overwhelms the mass of groundwater moved around by pumps, as well as any ice mass changes in the polar regions) move multiple centimeters per year. The Indian plat moves about 15 cm per year, which is why the world’s most massive mountain range, the Himalayas, are still growing higher, despite erosional loss, at a rate of 0.5 cm per year.
Just try to imagine the eccentric rotational momentum exerted on the earth’s rotational axis just by the rise of the Himalayas alone – not to mention the rest of the moving continental plates. Plus not just the Continental plates, but also the oceanic plates, and the effects of oceanic rifting and subduction.
These warmunists are such scientific ignoramuses!
A dedicated person could probably make a “pretty good” model to predict the changes described. It seems like that person would conclude early on that the changes would be nearly invisible relative to “everything else”.
The lithosphere, crust+upper mantle not just the crust, resides on zones of partial melt, not liquid. It is soft enough to allow plates to move but not so inviscid that one would consider it a liquid over anything but geological time scales.
“By pumping water out of the ground and moving it elsewhere, humans have shifted such a large mass of water…”
that statement implies the water pumped out, is never replenished…
Those of us that grew up in the country (that is…USA non cities) where the homes had a well, and the water was pumped out for years…50, 60, 70+ and the water level in the well never went down. The understanding was that water pumped out was replaced by rainwater into the ground.
How is it that we have streams flowing out of the ground, even in drought times, that feed into the water flow, rivers to the sea…if that water is not Replaced by some cycle?
It is true that replenishment occurs. It is also true that in some areas the water table is getting deeper, and in some areas water use is causing earth subsidence, which means that water is not there any longer. Things are never as simple as the modelers would like.
But even when groundwater is “mined” (lower water table elevation) it still does not get destroyed eliminating its impact on rotational momentum of the earth as the study authors assert. It merely moves a relatively short distance, negligible as far as rotational momentum is concerned. It still ends up in the same place – the oceans, or recycled on the earth’s surface, from one aquifer to another nearby aquifer, or to a surface reservoir, or biota.
The earth is a closed system, hydrologically. Water is neither created or destroyed, nor gained or lost. And the effect on the earth’s rotational axis of groundwater withdrawal is negligible compared to the rotational momentum effects due to plate tectonics, which the study authors ignored because they are not geologists but are merely computer model jockeys.
Groundwater can be pumped out faster than rain replenishes it.
California’s central valley has sunk something like 22 feet since Gold Rush days, so I have heard.
Nuclear power/distillation. Israel can do it, so can California. Bonus, use the excess nuclear power generated electricity to compensate for their unreliables.
So where did that groundwater go? It wasn’t removed from the planet.
It went somewhere else. That is enough to impact the rotation of the earth. Yes it is still in the “system”, however how mass is arranged within the system is different.
Whether it’s one meter, or something less, it will still have an impact.
The questionable things in this study are primarily the assumptions of how much water has been pumped and their apparent failure to account for some aquifers refilling.
When the Kobe earthquake struck, the ground in that region subsided several meters, that had a measurable impact on the earth’s rotation, it sped up by a tiny, tiny amount.
No – impacts are either significant, or are insignificant. Groundwater pumping is clearly insignificant and is non-measurable by any existing instrument. Sure, the polar axis location has moved a (barely) measurable amount (cm), but that is entirely do the immeasurably larger factors such as I pointed out, including plate tectonics as well as astrophysical phenomena.
If a theorized effect is so small that it cannot be measured, and if is theoretically insignificant compared to other effects that are easily measurable (and actually has been routinely measured) then such theoretical effect must be ignored … as groundwater pumping must be ignored.
Where did I say that the amount was significant?
Does the movement of the pole(s) stabilize when there are torrential rains which refill the aquifers?
How about modeling the effect of floods?
This is why Florida needs tropical systems, to refill the aquifers.
“The earth tilted east.”
I thought that from the North Pole you can only go south. East? The mankind is destroying everything.
They cover that in image “(b)” in the story above. The trouble is that their diagram makes it look like the north pole has moved a whole lot, which it hasn’t. ie. the radial scale doesn’t represent distance.
Any surveyor will tell you that the north pole doesn’t point directly at the North Star. Also, the geographic north pole has pointed at different stars during the last couple of thousand years of written history.
The paper talks about the amount of water pumped but a lot of subsurface water flows naturally.
link
Wow. The stupid just gets more stupider and more stupider every day.
Agreed entirely. The tragedy is that intelligent people have to waste time reading this utter bilge. It serves as evidence that “peer reviewed research” doesn’t in fact mean anything any more. You can get any piece of silly nonsense “peer reviewed” and published. Albert Einstein famously note that, “Only two things are infinite: the Universe and human stupidity.”
There was a warning, but unfortunately it is inconveniently at the end of the article.
Always check the bottom to see if the BS tag is there (YouReekAlot!)
“ intelligent people have to waste time reading this utter bilge”
have to? It’s a (bad?) choice.
Even reviewers can say no.
You sure got that right .
And to think some one is getting paid to write this rubbish.
Have they never heard of tectonic plates and how continents have moved for millions of years. .New Zealand was part of Gondwanaland and split from it 170 million years ago and we are now 1056 miles from mainland Australia .
Some countries are getting short of ground water because of over use but most water is pumped from the top 200 meters and I cannot see how the extraction of water can alter the earths rotation .Next they will be telling us that New York sky scrapers are going to put a wobble in the earths orbit and we are all doomed.
Not their area of expertise. The number of times people forget to factor in the obvious is surprising.
I read that the giant Chinese dam changed the earth’s speed or tilt when it was full. So what? Gravity waves from a black hole merger squeeze the earth very slightly and it is measured….tiny movements happen.
Every movement on the planet impacts the planet’s rotation. For most of these actions, the shift is less than the size of an atom.
When you get in your car and accelerate towards the east, the earth’s rotation slows down. Of course the change in rotation is just a few tiny fractions of a pico second. When you come to a stop, the rotation returns to its pre-trip value.
Just because a change is too small to measure, or can’t be picked out from the noisy background, doesn’t mean it isn’t there.
For the purpose of determining effects and making decisions, such infinitesimal factors must be ignored – they are not there for any rational purpose.
I don’t see anyone claiming that decisions need to be made based on the results of this study.
The Nigerian spammers are getting more and more sophisticated.
I got one the other day… they said according to their climate models, the world would end in 12 years, 3 months, 11 days and 4 hours if I didn’t give them my bank information.
No, according to St. Greta, the Earth ends in 4 days. Just in time for the start of summer.
i’m not a geophysicist, just an engineer, want to make sure I have this right. The estimated mass of the earth is 6 x 10^24 kg. 2,000 gigatones (2 x 10^12 kg). So the ratio of all this groundwater displaced (assuming it is not replenished with natural hydrological cycles) to the mass of the earth is 3 x 10^-13. To give perspective, that is like a single E. coli bacteria cell throwing a human off balance. But then again…climate change…where anything is possible.
I am sure you are right, 1 part in 10^12 ! Gosh thats nearly as much as the 1 in 10^12 molecules CO2 we are claimed to have put in the atmosphere. But measure it in Gigatons and it must make a difference.
Kind of like zetajoules of change in the ocean, right?
As long as nobody mentions mining. In Oz alone one miner shifts over 155MT of iron ore per year, and that’s from the 3rd largest, (maybe even fourth place now).
And don’t mention the coal. If this was shifted from south of the equator north of the equator, does that make Oz float higher in the mantle of should china sink? I need this clarified so I can feed it into a unique model and make a couple of outrageous press releases and hopefully secure some grants.
Please respond if you know, and for the record a WAG will do.
The circumference of the earth is around 40,000 km, or 4 X 10^13 meters.
By your calculations, the ratio of mass is 3 X 10^-13.
So it sounds like the calculated shift sounds reasonable.
Lots of commenters confusing “very small” with “nonexistent”.
This started with the bottled water craze. People just couldn’t drink out of the tap, they had to have bottled water. Now look what it’s done.
In plastic bottles no less.
And they think they are saving the Earth by switching to metal bottles.
What is the moment of inertia for the earth? The study doesn’t say and its obvious that tidal forces and volcanic activity change it every day. Doubtful that pumping water on such a relatively small area has much effect on these large changes.
A calculated movement of just one meter isn’t a large change.
All those wind turbines are blowing us fractionally further from the sun, so that helps counteract climate change and we should be okay.
If those wind turbines all faced the same way, would that affect the Earth’s rotational speed? Has no one got a grant to model that?
I’ve asked for that same model many times. I don’t know how I’d even do it. It seems like “how wind works” would be a natural part of “how climate works” but relatively free-moving, relatively light gasses must be the hard part of modeling.
Does anyone know where you apply for the grant funding for these oh so important research programmes involving computer models?
I only ask because it seems so much easier to sit on the computer engaging an AI chat maybe the one called ‘Al Gore rhythm’ which I think is something to do with birth control or was it the effect of gas build up? I forget now, sorry I digressed there, sorry, anyway I am reaching the stage when my wood milling hobby and other associated woody activities may have to give way to easier relaxing endeavours, perhaps some serious modelling? I was just wondering where I go to get the money? There is clearly plenty of it sloshing around judging by this latest reported global spin activity.
Let us hope they don’t model the impact on the earth’s of mass redistribution. If the continent of Antarctica moves to a warmer location for example. I wonder if that has ever happened before?
We could call it Go-wander-land.
If professors didn’t edit and take credit for ignorant kids writing sloppy papers, then imagine what would become of those kids. Every student at my college was required to produce some sort of capstone paper – college wasn’t just assumed to be part of life back then. – and some of the proposed paper topics were “amazing”. By “amazing”, I mean they made me wonder what I’d done with 4 years.
Sorry, my thoughts wandered- I’d meant to say “do you really want that job?”
1993 to 2010. Hmmm.. why stop the study in 2010? maybe this event corrected some of that shift?
https://www.nasa.gov/topics/earth/features/japanquake/earth20110314.html
Or maybe it added to it? We’re all doomed!
So maybe someone here can help me out. I thought even though we have been pumping the water out, doesn’t it still reach an equilibrium where it is stored in livestock, soil, dams, etc?
“doesn’t it still reach an equilibrium where it is stored in livestock, soil, dams, etc?”
The system reaches equilibrium when we (earthlings) stop making more livestock, soil, dams, etc. Humans – 8 billion strong and growing (and eating more).
Not heard from astronomers or navigators complaining about the stars and planets being in a different position!
Do these people not understand the damage they are doing to science itself with this utter nonsense?
They have absolutely no idea. They just have an unshakeable belief in their own self-importance.
Name of professor, work of students, assumption of “nobody’s going to read it anyway”.
Oh terrific! Yet another excuse to k!ll off humans. The pesky vermin are using water from wells. That must stop!
Perhaps a quarter of the 2-3 mm high tsunami of annual sea level rise comes from pumping groundwater. It threatens to…well, um, gimme a second..do unpredictable harm after a millennium or more.
The water is flowing out into the oceans and there’s no known mechanism for it to return to the continents! Now every schoolchild knows, even better than their pronouns table, that water doesn’t flow uphill! It’s just simple physics, people! Believe in The Science ™ willya?
Rain? What’s that got to do with anything?
So that’s the cause of all the other times the magnetic poles have wandered and reversed! /sarc
sea level rise due to groundwater withdrawal
Oh, so the less than 2mm/year is not from melting polar ice…
Ok !
These alarmista are so, so funny ! 🙂
They did say that the calculated amount was about 6mm over 20 years. That compares to 40mm of measured increase over the same time period.
It does show that the amount of melting is less than earlier claimed, since some of the SLR can be explained by other things.
Ángels on pin heads come to mind!
It’s noteworthy that but one of the seven ‘authors’ of this document from “The AMERICAN Geophysical Union” (located [supposedly] in Washington DC) has an Anglo-Saxon name. It certainly could make one suspicious that there is foreign, and not necessarily benign, foreign involvement in it.
“Made in Korea” was once a byword for utter trash, now it seems to be unaccountably popular whether it’s K-pop, K-fashion of K-films. Still the same old utter trash though.
Kia cars get good ratings
“The shifting of mass and consequent sea level rise due to groundwater withdrawal has caused the Earth’s rotational pole to wander nearly a meter in two decades”
OMG, it’s a disaster! How will we survive the pole having moved that much? We gotta do something about this- and move it back! 🙂
God save the Queen!
ha, ha- yuh, Biden said that recently
Perhaps he was talking about his son’s boyfriend ?
“We gotta do something about this- and move it back”
Mountaintop removal coal mining to offset?
Ik is alway good to read the actual paper and not the press release https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GL103509
What a crock of feces!!!
This study claims that groundwater pumping is “related to climate change”, which of course is preposterous. There is zero relationship between climate change and pumping of groundwater. There IS a relationship between climate and groundwater use, in the sense that groundwater “mining” is often but not always used when precipitation is reduced (ie desert areas). But groundwater is also frequently used over surface water sources due to pollution of surface water sources, or when flat topography makes surface reservoirs less feasible.
Secondly, their theory ignores the actual historic data that shows ice mass increasing in the polar glacial areas of the planet, not decreasing.
Thirdly, their study presumes that liquid water is somehow destroyed by groundwater consumption, which of course is bull honkey. The liquid water pumped from the ground is always returned to the ground, by way of return drainage to rivers from farm fields, discharges of treated wastewater to rivers, direct ground application (irrigation), and production of solid waste that either naturally biodegrades or is disposed under ground.
Any groundwater that evapotranspires from irrigation ends up only temporarily in the lower atmosphere, after which it precipitates back to the surface again somewhere downwind, possibly close by if a mountain range is downwind. In which case the water either ends up underground or running off and either ending in the ocean or gets recycled again.
The bottom line here is that all water beneficially used by humans is merely recycled and never destroyed.
And the earth’s axis has always moved about due to massive glaciation and interglacial events, erosion, plate tectonics and the movement of continental plates, and gravitational forces exerted on earth by the moon, sun, and planets in our solar system. It is unavoidable, natural, and of little to no consequence to humans or the environment.
It is obvious here that this study team went grant-fishing, and the surest means of winning grant funding is to claim a posited effect related to climate change.
And how many gigatons of solid material has been shifted from one location to another for things like building material, steel for cars and ships, etc. etc.?
AGU is another example of a so called professional scientific organization that has deteriorated into a gaggle of lemmings whoring for Fed grant monies. This is just sad.
Hey! When Leftist governments cast money far and wide what’s wrong with bending over to pick it up? All of that government money, however, has effectively stopped the advancement of science in the West. We’ll all just have to learn Mandarin and/or Hindi to keep up on scientific advances in the future.
A lot of things seem to be invented in USA after Y2K – like this web page? I do agree that the next generation of tech could come from other places, but as of now they seem to deploy their tech in the USA first.
Let’s do a little math here, with no fancy super computer necessary. Here is a very simple calculation that the study authors ignored:
The estimated worldwide withdrawal rate of groundwater is 92 cubic kilometers per year. That water is not destroyed or removed from the earth’s surface, but is merely moved around a little.
The study authors here ignored plate tectonics which moves the entire crust of the planet around in various directions and at varying rates, ranging from about 1-2 cm per year to 15 cm per year depending upon the plate. All geologists know this stuff quite well.
Now, just take one single tectonic plate, one of the smallest on the planet: the Indian plate, which is moving northward at a rate of 15 cm per year. The surface area of the Indian plate is 11.9 million square kilometers, while the average thickness (relatively thin compared to other tectonic plates) is 100 km. The volume of the Indian plate therefore is approximately 100 x 11.9 million km cubed, or 1.19 billion km cubed.
Using an average density ratio between silicaceous rock and liquid water of about 2.7 to one, then the mass of the Indian plate is approx.1.19 billion times 2.7 divided by 92, which is 349million times the mass of all the groundwater in the world! Just one small tectonic plate!
Given that rotational or angular momentum on a spherical surface is directly proportional to both mass and velocity, and the velocity of the Indian plate is 15 cm per year, and the velocity of changes in groundwater location on the earth’s surface per year has to be very small – it has to be less than 1cm per year – then it is quite obvious that the rotational momentum effect on the earth’s axis due to the movement of the world’s smallest continental plate is fantastically larger in magnitude than the rotational momentum effect of all of the world’s groundwater withdrawals even assuming that the groundwater somehow simply disappears from the planet, which is of course preposterous.
“is fantastically larger in magnitude than”
Tiny and nonexistent are not the same thing.
How can change in sealevel be the cause? Water is drawn from aquifers nearlt well above sealevel. So, for a start, even if you imagine this makes it to the sea, then the average mass of earth’s water is lower than it was before, not higher. Duh!
Now, looking deeper into the problem, much of this drawn water is taken up by crops and also evaporated into the air. The weight of the crops has shifted the average mass of the earth outwards. Since most crops dont need groundwater, rain does the job, then the mass shift outwards because of the weight of the crops isnt all wellwater.
Getting more complicated? Getting to the sea by rivers, some of this original wellwater is also withdrawn for irrigation downstream (more crops!) and town supply. Do you know that doing mass balances in a manufacturing plant or mine processing plant is generally done by a specialist. Takeaway: the researcher has it backwards.
The point is that the location of the oceans where the water ends up is not the same location as where it started. By changing altitude, the water will change the rotational energy of the earth, by a very tiny amount.
By changing it’s physical location, it affects the axis of rotation, also by a very tiny amount.
Nobody so far has mentioned spinning ice skaters pulling arms in and out, or mentioned twisted up school yard swing set chains. So sad.
In 2018 the US estimates there were 11.4 million illegal immigrants in the US.
(Of course a lot more have come since then!)
Assuming an average weight of 150 lbs. that would be a shift of about 845,000 tons.
Do they count?
“Based on climate models, . . .”
First sentence of second paragraph of AGU press release in above article.
Stopped reading right then and there.
Billions of tons of ice melt each year either at the north pole or south pole and then it is replaced months later. Some say it is not all replaced each year. Speaking in terms of a spinning ‘top’, that would seem to imbalance the top and bottom of the ‘top’ regularly.
How would pumping groundwater from under a small part of the land area compete with that? Especially since much of it is replaced by precip every year.
Not an answer, but related to the question: Angular momentum calculations involve radius, distance of a mass from the rotational axis. In the case you describe, the pole water has a large disadvantage relative to equator water.
They’d have better luck claiming dense urban development and dams have “nudged” Earth’s spin.
I suppose this theory could be correct, but as long of their estimate is based solely on making their model fit the observations, it is not a finding, but rather a theory. there may be other unexplained factors that play a major role.
Not even a theory, but a conjecture.
2,150 gigatons of groundwater, are 2.15E12 liter,
there are more than 7E9 people on this planet and the observed time span was 17 years,
So we are talking about less than 20l (about 5 gallons) per person per year, about an ounce per week. I would say the order of magnitude is about right, if not a bit low.
Your point is not clear to me.
next they’ll argue that you can spin faster with your arms across your chest
You would know all about “spin”…
It is what BEST hired you for.!
No, they are arguing that you spin faster if a hair fell out of your left nose. And just think what would happen to your spin if you bought a ball-tucking swimsuit at Target.
DF: I have actually not taken up biking because it seems to require spandex shorts that I don’t prefer. Men on bikes who wear loose running shorts have become anachronistic.
Others: “I don’t care what other people think.” Yeah, yah do. This is a _comment_section_.
All except the obligatory “worry about sea level rise” this is an interesting paper. I note that there was no mention of glacial rebound as a factor. The polar moment J2 has been declining for a long time, throughout the satellite era at least, and it is reasonably shown to be the result of rebound. Since rebound has a complex spatial pattern I wonder about its influence here.
I also wonder if this secular drift of the pole leads to an accumulation of errors in eclipse observations versus predictions? I also note that large scale irrigation tailwater travels in rivers down to the sea, there is also an enormous discharge of groundwater unseen and poorly known directly to the ocean above the continental shelf.
Lucky we’re not in Guam.
What a crock.
If true, how much did the Earths rotation change with each ice age as millions of tons of ice formed at each of the poles. How much has the Earths rotation changed as the crustal plates move in imperceptible ways, yet continue to form mountain ranges.
Where is the control group? All other factors (mining, recharging basins, etc.) would have to be controlled for. So this is not science.
Mining is an interesting idea. I wonder whether we dig deep enough for high-density, high-volume ore to cause a long term shift in mass distribution. In theory, every time we exhale we would cause a vanishingly small change in rotation.
“Does oil float to the top or bottom?
Because oil is less dense than water, it will always float on top of water, creating a surface layer of oil.”
I wonder has anyone asked them to model oil extraction? maybe it was a practice run.