The original URL for this was woeful, while it did link to your link above and via that to Geophysical Research Letters it still makes more sense to directly link to the actual primary source, either the ELI5 AGU press release or the actual paper in GRL.
HN has a technical audience that appreciates primary sources.
For what it is worth, starting out with "for fuck's sake" makes me think you are an asshole. It starts a combative relationship. Your comments work well without that. Better, I'd say.
I provided the original apparently shitty link (as measured by upvotes to your comment) to accomplish a secondary goal of introducing those who may enjoy it to the super minimal aggregator. I thought I was helping expose more fun stuff in the single submission.
You are absolutely right that the primary source is a much better link to provide. I'll do better in the future.
> For what it is worth, starting out with "for fuck's sake" makes me think you are an asshole.
Alternatively I'm an Australian talking conversationally as Australians do, and one with a geosciences background, some > 1 million SLOC of geophysical codebase and 40 years on forums going back to pre WWW Usenet.
I have no control over what you think, but I'm happy to share thoughts given you've opened the door.
What you saw as a super minimal aggregator that exposed fun stuff, I saw as a little known URL domain of unknown provinance making bald statements indistinguishable from others of that ilk "Earth tilts | Pole Shifts | Sea level rises | Lab leaks | Fake News".
The guts of the story is in the details, the context, the methodology, etc.
If I wanted snappy clickbait titles with minimal content I'd stick with Fox News .. but I'm from the country of origin of Murdoch and he left due to widescale community pushback on his plans to dominate media and dumb down information (although he retains a toehold here with Sky News and a few newspapers).
You seem like a communicative well intentioned contributor, I bear you no ill will and look forward to your future submissions, ideally ones with substance.
2 trillion tons = 1/3 of 1 billionth of the mass of the earth. the distance from the ground to the surface is around 5 millionths of the radius of earth (like 100ft)
So you're talking about a change in angular momentum that is on the order of 10^(-20) times the angular momentum of earth (mr^2 \omega).
A change in the pole of earths rotation by 31 inches (10^(-7) times the radius of earch) corresponds to a change in angular momentum on the order of 10^(-14). So we seem to be off by 7 orders of magnitude.
Your computation is very wrong, as explained in the actual research paper and in another comment here. The water is not moved only from under the ground to the surface and the effect on the axis is not due to raising, but mainly to horizontal movement.
Changes in terrestrial water (urn:x-wiley:00948276:media:grl65897:grl65897-math-0001) (e.g., Figure 2a) and oceanic (urn:x-wiley:00948276:media:grl65897:grl65897-math-0002) (Figure 2b) mass loads were converted to spherical harmonic (SH) coefficients of the geoid:
urn:x-wiley:00948276:media:grl65897:grl65897-math-0003
(1)
where urn:x-wiley:00948276:media:grl65897:grl65897-math-0004 is the Earth radius times water density, urn:x-wiley:00948276:media:grl65897:grl65897-math-0005 are latitude and longitude, urn:x-wiley:00948276:media:grl65897:grl65897-math-0006 are normalized associated Legendre polynomials and urn:x-wiley:00948276:media:grl65897:grl65897-math-0007 are load Love numbers. Using the combined mass fields, urn:x-wiley:00948276:media:grl65897:grl65897-math-0008 PM excitations (urn:x-wiley:00948276:media:grl65897:grl65897-math-0009, urn:x-wiley:00948276:media:grl65897:grl65897-math-0010) were computed from the degree 2 (urn:x-wiley:00948276:media:grl65897:grl65897-math-0011) order 1 (urn:x-wiley:00948276:media:grl65897:grl65897-math-0012) SH coefficients via (Chao, 1985; Seo et al., 2021):
urn:x-wiley:00948276:media:grl65897:grl65897-math-0013
(2)
urn:x-wiley:00948276:media:grl65897:grl65897-math-0014
in which M is the Earth mass, and C and A are Earth principal moments of inertia. urn:x-wiley:00948276:media:grl65897:grl65897-math-0015 and urn:x-wiley:00948276:media:grl65897:grl65897-math-0016 from Equation 2 include effects of rotational feedback. We then estimated monthly (urn:x-wiley:00948276:media:grl65897:grl65897-math-0017, urn:x-wiley:00948276:media:grl65897:grl65897-math-0018) changes from groundwater (storage on land and associated sea level change) plus the other sources (AIS, GrIS, glaciers, dams and soil moisture). urn:x-wiley:00948276:media:grl65897:grl65897-math-0019 and urn:x-wiley:00948276:media:grl65897:grl65897-math-0020 are mostly determined by terrestrial storage changes with minor contributions from corresponding sea level rise due to relatively uniform distribution of ocean mass as shown in Figure 2b.
> the distance from the ground to the surface is around 5 millionths
The water from aquifers is not just lifted a short distance up to the surface. It is used, ends up in rivers, and spreads around the world's oceans. And the places where we are pumping groundwater are not uniformly distributed around the Earth. We are essentially moving mass to the Pacific.
Yeah I don’t know that this even makes sense at a glance. How much mass do we expect just moves around by natural processes? Should we even expect to be able to detect an effect of this magnitude (as in, distinguish it from noise)? I do not think so:
- Based on a cursory search, a large iceberg may weigh in at ~1 trillion tons. The calving process moves mass hundreds of kilometers away from Antarctica. This should be an effect of similar magnitude!
- The water cycle moves ~500 trillion tons of water each year. This water is moved hundreds of kilometers and isn’t evenly distributed over the course of a year. We should expect the impact of seasonal fluctuations in water distribution to thus have a comparatively much larger impact on the earth’s rotation.
I don’t think these numbers add up. I think we’re reading this story because it feeds into a certain kind of “we are hurting Mother Earth” mindset.
The largest iceberg ever measured, B-15, had a mass of about three billion tons. Still enormous, but not trillions, which sounded unbelievable enough to prompt me to look.
A-68 was part of Larsen C, a section of the Larsen Ice Shelf. Scientists found the crack beginning to form in November 2016. Scientists assess that A-68 "didn't just break through in one clean shot, [but] it formed a lace-network of cracks first."[5] The resulting iceberg was around 175 km long and 50 km wide, 5,800 km² in area, 200 m thick and weighed an estimated one trillion tonnes.[8][5]
I’m not sure if Wikipedia is right here however because the linked sources have changed to remove mentions of mass.
That said we should be able to do a pretty dumb calculation. 1 km3 of water weighs ~1 gt.
5800 km2 x 0.2 km = 1160 km3
1160 km3 of ice x 0.9 (density of ice compared to water) x 1 gt / 1 km3 leaves us with a mass of about 1044 gt or around 1 trillion tons.
Edit: also, I am not able to find an original source for the mass of B-15 being in the few billions range
The calving process results in ice already floating in water moving. Archimedes' law means the effect is very limited ~ the height the ice sticks above the surface and the little change in density.
More importantly, the article mentions removing annual effects on Polar Motion. They are averaging - somehow - to look at permanent changes. The annual effects may be an order of magnitude greater, it is not relevant.
~8 trillion tons to raise the level an inch based on the simple math of surface area of a 24,000 mile diameter sphere, times 2/3rds water, as seen here:
So we want to calculate the change in momentum caused by moving water from just under the surface to the surface.
Assume earth is a perfect sphere, let m be the mass of earth and r be the radius of earth. Let rdm be the relative mass of the water moved = 3e-8, let rdr be the relative distance of the water moved = 5e-6.
The change in momentum is rdm.m.(1+rdr)².r² - rdm.m.1².r² which is 2.rdm.rdr.m.r²= 3e-14mr². Looks about right for the change of axis you wanted.
There's other counter arguments but at least the oom analysis fits.
This sounds truthy to me. Can anyone confirm, and also weigh in on whether uneven distribution of the moved mass might account for any of the missing orders of magnitude?
Groundwater is mostly under ground... And the center of mass of all the surface crust is hundreds of kilometres from the center of mass of all the world's oceans.
Scientists and researchers collect two decades worth of data and publish peer reviewed papers.
Genius HNer looks as the title, spouts some factually incorrect data to "debunk" it and gets upvoted to the top.
Sadly I'm not just describing this instance but internet discource in general. Critical thinking and analysis is dead in the age of "gotcha" hot takes.
ironically this comment is annoying and pointless cynicism and meta commentary while the original comment is interesting, although apparently wrong - your response should be deadlast but unfortunately I see it before the other comments explaining where in the paper to find why this reasoning is wrong...
This seems to happen a lot here lately, particularly on earth and space science related topics. After you read the comments on a paper in your field, it becomes depressingly obvious that a lot of the most upvoted commentary is armchair skeptics doing back of the napkin math that sounds good but falls apart upon closer inspection. Gell-mann amnesia effect, etc.
Something else is happening in sone cases. You have research that tells you something, the press picks it up/exaggerates it to the point that it's no longer connected to the real thing + now we are all talking whatifs and have opinions without reading the initial claims.
In cases like this it's more than fair to call bullshit.
An appeal to authority would be “Experts disagreeing with you proves you wrong.” That’s not what they’re saying.
They’re taking as read that the top level comment is wrong (as explained by a number of other comments), and making an observation about the circumstances surrounding the incorrect comment, as well as the theme it represents in the broader discourse.
Totally. Prima facie bullshit. Problem is that the "I F@#$king Love Science" crowd doesn't actually know how anything about science or math, so they'll buy pretty much anything backed up by even low-quality technobabble.
By modelling the previous location of groundwater (under the ground), and the new location of groundwater (on the surface of the ocean) one can calculate the change in the earths rotational axis that is expected. The measured change matches predictions only if this effect is considered.
The location changes the axis because most land is on one side of the earth (centered around Europe), and most ocean is on the other side (centered around the south Pacific). Move mass from one place to another, and the axis changes.
I am not saying the premise is BS, but like all engineering and science you create a hypothesis for a phenomenon, in this case the pole shift, to address it, and you create the formulas and parameters to be included and used. As others have pointed out, there are potentially a lot of other variables to be considered that they possibly did not include. To further test the hypothesis, they need to sharpen their pencils for round two or three. Some off the top of my head: if there are higher drought areas or more wetter areas due to climate change, did they consider that shift? Location, position, and magnitude of snow-melt basins, glacial melt and polar cap changes, earth moving human activities on scale by all nations (China making artificial islands, etc.), earth moving due to climate change - floods, drought, large volcanic eruptions, underwater tectonic activity - all an ongoing process), etc...
The father/scientist of the article should not put his pencil down just yet. Very interesting hypothesis so far.
I've always wondered, once we get into asteroid mining, whether there will be a global "massening" if we bring more matter back to the planet. If the orbit should change and you know, cause problems and whatnot.
In medievil times Alchemy was the search for changing base metals (mostly lead) into gold. Clearly unimaginable riches would follow.
What they didn't realise was that turning lead into gold does not make lead as valuable as gold. It makes gold as valuable as lead.
This has happened before. Aluminium used to cost more than silver. The Washington Memorial is capped in aluminium for all of about 9 inches high, at fantastic cost.
Development of the Hall process made aluminium plentiful. It's now a cheap house-hold item we discard daily.
If we found a billion tons of gold, the value of gold would crater basically to the cost of actually bringing it to earth. We'd find uses for it (its pretty) but it'd make a terrible building material :)
What they didn't realise was that turning lead into gold does not make lead as valuable as gold. It makes gold as valuable as lead.
Only if the process was commonly known. Alchemists were quite a secretive bunch. For example, if you asked most people to name a famous alchemist they'd probably come up with nothing, despite Isaac Newton being one. https://en.m.wikipedia.org/wiki/Isaac_Newton%27s_occult_stud...
It doesn't matter - even if you're the only one to know the trick, once you start dumping large amounts of gold on the market, its price will start to go down. Gold isn't something that gets easily used up, so the more of it is in circulation, the cheaper it gets.
Steady state thinking. Of course gold would become cheaper, sure. But you will have bought all the actual productive assets first!
This is the same trick economists play when saying "inflation doesn't matter". It doesn't in the steady state, but in the meanwhile, I printed the money and gave it to my friends, who do you think is going to end up owning all the hard assets?
In that time "ownership" of assets was a highly fluid concept. Kings nominally owned all the assets already, and as more than a few discovered, loose is the head that wears the crown.
Yeah, human psychology is the real philosopher's stone, huh? Make people feel like it's valuable and it becomes as such. If Graber's work is to be trusted the review of the development of gold as a token of exchange has little to do with its innate properties, and more to do with the fact that the state institutions demanded taxes be paid in said tokens.
It would have been nigh impossible to keep it a secret. Locally your sovereign would find about it very quickly. So you're working gorgeous the crown in a short order.
Operational security was also terrible, so it wouldn't have been kept as a secret limited to one country for long.
If you want to profit from making gold, you have to spend gold, and that's going to get noticed very fast. Its not like the common man was spending gold coins on a regular basis.
This plot point in Goldfinger blew my mind as a teenager (spoiler: Goldfinger does not want to steal gold - he want's to make the gold in Fort Knox radioactive, to raise the value of the gold he has). If there is one important subject that is not that hard to understand, but poorly understood by the general public, it's how markets work. I know many well educated people who make trivial mistakes when thinking about markets.
The mass of the Earth has no impact on its orbit. Think about it this way: the northern and southern halves of Earth orbits the sun in exactly the same orbit as the full Earth. Now, if we increased the mass of the Sun, however…
Even 2 trillion tonnes sounds like a very small amount of water compared to what must be getting redistributed by climate change? The Antarctic ice sheet alone weighs around 25,000 trillion tonnes. So even just melting 0.1% (25 trillion tonnes) of it would move far more water into the oceans than we've ever pumped from groundwater!
>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.
That's nothing compared to the interglacial-glacial 100,000 year cycle that set in since the Pliocene Era (c. 3-5mya). Current activity is kind of interesting though, accelerated time-frame-wise:
> "At the same time, there are a lot of new salmon streams opening up in Glacier Bay, says Eran Hood, professor of environmental science at the University of Alaska. “As glaciers are melting and receding, the land cover is changing rapidly,” he says. “A lot of new areas becoming forested. As the ice recedes, salmon is recolonizing. It’s not good or bad, just different."
Human activity has become the dominant feature in most if not all ecosystems on Planet Earth, that's just the reality. The trigger has been pulled, welcome to the now.
> "As our gargantuan glaciers melted, the continents up north lost weight quickly, causing a rapid redistribution of weight. Recent research from NASA scientists show that this causes a phenomenon called “true polar wander” where the lopsided distribution of weight on the Earth causes the planet to tilt on its axis until it finds its balance. Our north and south poles are moving towards the landmasses that are shrinking the fastest as the Earth’s center of rotation shifts. Previously, the North Pole was drifting towards Canada; but since 2000, it’s been drifting towards the U.K. and Europe at about four inches per year."
So, I guess if we have a 31 inches over 17 years change via groundwater pumping, then we have 80 inches over 16 years due to glacial melt... how do they sort all that out? Did they even take the glacial factor into account?
The article reads like the opposite to FUD because it's dry. Instead it's more like 'People previously estimated how much groundwater was pumped to the sea. If it is that much earth's axis should tilt like this. We checked, it does. It is actually the second biggest variable to explain permanent axis drift.'
It's not a distraction, it is confirmation. In the future we can confirm groundwater pumping estimations by looking at axis tilt and it becomes harder to deny it happening.
EDIT: Reread the abstract. The previous estimations did not have direct evidence, this is such evidence.
To put this in perspective, ringwoodite in the mantle is estimated to hold up to 1% water. If estimates are correct this implies it holds three times more water than all of the oceans on the Earth's surface.
I’m really curious how much all our aquifer draining has added to sea level. I have no idea what the scale is. But I suspect it is enough to show up in measurements.
Note this is for the years 1993-2010 only. But don't extrapolate 25% of the time to 16% of the sea level rise since the 1950's is caused by pumping unless you write a sourced paper.
I’m not sure if I’m supposed to panic more because we’re tilting the earth, or panic less because we’re melting less ice than we thought. Or panic the same because the jury is still out in this research.
Is this some kind of anti humanity to think that every generation fucks up the earth in their way and increasingly and if that means the humanity ceases to exist that’s okay, because either I won’t be alive by then or if it happens in my time then eventually I die anyway and there’s nothing after that? So that’s fine. I mean let’s try to fix it, if not just fuck it and stop fretting over it. Let’s get done with either way.
Thank you but I didn’t mean that and I am aware of that word. I meant actually “anti humanity” — something that kinda goes against the grain of humanity. Inhuman didn’t cut it either.
Otherwise I’d have said “am I a misanthrope”. No I don’t hate mankind at all and what I mentioned isn’t hating either.
I hope I was able to explain that I did believe that word wouldn’t fit in for what I wanted to say. Maybe some other word? sch………ude isn’t that word either I guess.
It still sounds like misanthropy to me, but whatever you want to call it, I’m cool with it.
It sounds like what you’re getting at is a general sense of disenchantment with humans. Blessed are we that we have the capacity to look forward to our own demise, yet blanket our children with the picric acid of our lack of interest for solving it.
As someone with kids, I have a vested interest in solving humanities existential problems, but also lack the ability to actually do it. It’s bothersome.
I am certain it's not misanthropy at all; and even with your very personal context what I feel isn't what you tried to fit (and I respect your attempt and reasoning here) in terms of meaning of the word with. But acknowledge that you feel differently about it. We just disagree here. Cheers.
Excess groundwater extraction already causes numerous issue across the globe without considering a small effect on the Earth's tilt. Surely you don't need to accept any of the climate change science to accept that making the world a better place, doing less harm and using limited resources at a slower rate is a good thing. That's just simple thoughtfulness, common sense and good planning (all things humans are often terrible at).
Yes. We are mining water. While notionally replenishable, we are withdrawing from the water table in many areas (I'm familiar with California) so much faster than the replenishment rate that the aquifer is collapsing, meaning it will never be able to hold the water it used to anymore.
For California, the bulk of the water is sprayed on plants and evaporates. A solid 80% of the water used by humans goes to agriculture. The plants are shipped all over the world. In a very real sense, California agriculture is about mining water and then shipping it elsewhere.
For the remaining 20%, it gets used by industry (10%) and residences (10%), where some of it goes back into the ground because it's watering the grass, but the bulk of it gets sent down the drain, in some cases to be reclaimed and reused (toilet to tap sewage systems) or sent to drain the the ocean.
For other states the ratios are different, but California in particular is egregious in agriculture's abuse of the aquifers.
Yes. But it depends on the aquifer. For example the Edwards Aquifer in Texas gets recharged from rainfall. But the Ogallala Aquifer supplies water at least 10,000 years old and rain doesn't affect it. Once we pump the Ogallala dry it will stay dry.
We pump it up by the megatonne over decades, we spray it outwards for crops or to water animals.
Some travels back down through the soil, most either evaporates or is taken up by plant matter, sweat out, goes to meat, etc. - which results in movement of the water mass to elsewhere on the planet.
Groundwater reservoirs have a recharge rate. That is the rate that surface, or I suppose even deeper, water is sequestered in the layer in question. We are extracting faster than that recharge rate.
Groundwater naturally is somewhat steady state. You get rain, it filters through and then there is spring or something somewhere and goes back to cycle in river or evaporation. Part of the cycle.
Now if you remove more water than exit through the natural processes you move it out from groundwater table. Thus creating imbalance and changing the steady state.
There are many ways to recharge the ground water. One is filling up dedicated basins periodically and letting the water trickle down. These basins are managed regularly to allow the water to percolate. Rivers also help with ground water recharge but only within their watersheds and routes. Also, Newsom in California recently issued an executive order to use flood water from recent rains for ground water recharge. https://www.gov.ca.gov/wp-content/uploads/2023/03/Refilling-...
and obviously the greatest source of land loss is ground water depletion near the sea. We need to replenish aquifers even if studies like these are just made up. And heck we could even raise our land near the sea rather than messing with dikes.
since we live on Terra, it has always had by definition terra-form, but if you use it to mean "make it support more humans inasmuch as we think we know how to do that", are you saying we're making it better or worse, unintentionally?
or are you just using it to mean "making planet-scale changes"?
Drift of Earth's Pole Confirms Groundwater Depletion as a Significant Contributor to Global Sea Level Rise 1993–2010
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/202...
or even the official press release?
https://news.agu.org/press-release/weve-pumped-so-much-groun...