Earth Tilted: We’ve Pumped So Much Groundwater That Earth’s Spin Shifted

Scitech Daily ^ | JUNE 20, 2023 | By AMERICAN GEOPHYSICAL UNION

[Red Badger]

Groundwater extraction and redistribution by humans caused the Earth’s rotational pole to shift nearly a meter in two decades (1993-2010), contributing to a sea level rise, reveals a study in Geophysical Research Letters. The most water redistribution occurred in western North America and northwestern India, and efforts to reduce groundwater depletion in such areas could theoretically affect this shift. The phenomenon doesn’t risk shifting seasons but could impact climate over geological time scales.

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.

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 on June 15 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.”

Observed Polar Motion Groundwater Mass Redistribution

Here, the researchers compare the observed polar motion (red arrow, “OBS”) to the modeling results without (dashed blue arrow) and with (solid blue arrow) groundwater mass redistribution. The model with groundwater mass redistribution is a much better match for the observed polar motion, telling the researchers the magnitude and direction of groundwater’s influence on the Earth’s spin. Credit: Seo et al. (2023), Geophysical Research Letters

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.”

Reference: “Drift of Earth’s Pole Confirms Groundwater Depletion as a Significant Contributor to Global Sea Level Rise 1993–2010” by Ki-Weon Seo, Dongryeol Ryu, Jooyoung Eom, Taewhan Jeon, Jae-Seung Kim, Kookhyoun Youm, Jianli Chen, Clark R. Wilson, 15 June 2023, Geophysical Research Letters.

DOI: 10.1029/2023GL103509

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

[Red Badger]

Now we’ve done it! We’re tipping over!...................

[Dave911]

BS to the n’th degree.

[Secret Agent Man]

Try 3 gorges and their whole south-north water diversion. The 3 gorges actully messed with the earth’ rotation.

https://www.kinetica.co.uk/2014/03/27/chinese-dam-slows-down-earths-rotation/

[Red Badger]

[dforest]

That RAT Hank was a genius.

[JudyinCanada]

I think it likely happened when Christie and Barr got together to do some rino plotting.

[dangus]

“...contributing to a sea-level rise.”

Well, technically, if a snowflake hits the ocean, it contributed to sea-level rise. (Either type of snowflake, by the way.) The question is how much. I’m guessing this is something like .000001 mm.

[VTenigma]

Sure, OK.

[Magnum44]

More junk science and voodoo. The Earth 'wobbles' all the time. Google Earth polar motion...

[teeman8r]

why does the earth wobble?

umm... climate change?

or perhaps it is a sphere spinning in the vaccuous darkness of space...

or perhaps because Americans are obese... many things it could be...

[Skwor]

Utter Junk Science. From the plain language summary, tell me if you see the problem:

Melting of polar ice sheets and mountain glaciers has been understood as a main cause of sea level rise associated with contemporary climate warming. It has been proposed that an important anthropogenic contribution is sea level rise due to groundwater depletion resulting from irrigation. A climate model estimate for the period 1993–2010 gives total groundwater depletion of 2,150 GTon, equivalent to global sea level rise of 6.24 mm. However, direct observational evidence supporting this estimate has been lacking. In this study, we show that the model estimate of water redistribution from aquifers to the oceans would result in a drift of Earth's rotational pole, about 78.48 cm toward 64.16°E.

IOW, they are making it all up from models, no actual empirical data supports any of this.

[MtnClimber]

Another reason to shut down farms. We should be willing to starve to save Mother Erf.

[butlerweave]

but the water is still here and when you pump it out doesn’t more flow in ,LOL

[ConservativeInPA]

It’s one BS article per day from this publication. Anyhoo, we better be careful and not tip over Guam.

[CIB-173RDABN]

I don’t believe this. Fake science to support the big lie.

[TomGuy]

Houston, I have found the problem:

Based on climate models,

[bwest]

Global tilting! We’re doomed!

[IC Ken]

They can’t make up their minds. Last year they stated it was from the weight of all the concrete China poured.

[JeanLM]

I question any model that deals in centimeters in relation to the whole overall dimensions of the earth. The precision of measurements of the earth from an observer on it can’t be that accurate.

Also in my miniscule portion of the earth, I have a well and a septic system, so what I extract goes right back where it came from. So my extraction if it’s part of the study should be eliminated. There are probably a lot of similar cases say in agriculture.