Claim: groundwater depletion releases ‘significant’ carbon dioxide

From the AMERICAN GEOPHYSICAL UNION and the “giant sucking sound” department:

Groundwater depletion could be significant source of atmospheric carbon dioxide

WASHINGTON D.C. — Humans may be adding large amounts of carbon dioxide to the atmosphere by using groundwater faster than it is replenished, according to new research. This process, known as groundwater depletion, releases a significant amount of carbon dioxide into the atmosphere that has until now been overlooked by scientists in calculating carbon sources, according to the new study.

The study’s authors estimate groundwater depletion in the United States could be responsible for releasing 1.7 million metric tons (3.8 billion pounds) of carbon dioxide to the atmosphere every year.

Based on these figures, groundwater depletion should rank among the top 20 sources of carbon emissions documented by the US Environmental Protection Agency (EPA) and the Intergovernmental Panel on Climate Change (IPCC). This would mean the carbon dioxide emitted through groundwater depletion is comparable to the carbon generated from aluminum, glass, and zinc production in the United States, according to the study’s authors.

“We were somewhat surprised that this hasn’t been accounted for in the literature and in the [EPA and IPCC] evaluations,” said David Hyndman, a hydrogeologist at Michigan State University in East Lansing, Michigan and co-author of the new study accepted for publication in Earth’s Future, a journal of the American Geophysical Union.

Groundwater depletion’s impact on carbon emissions is significant yet relatively small compared to the leading contributors, according to the authors. For example, scientists estimate fossil fuel combustion in the United States is responsible for releasing more than 5 billion metric tons (11 trillion pounds) of carbon dioxide into the atmosphere every year, close to 3,000 times the amount released from groundwater depletion. Still, the study authors argue that understanding all sources of carbon dioxide emissions is important for making accurate climate change projections and finding solutions.

“It’s not going to change the way we think about global climate change. It’s just another factor involved that we need to consider,” said Warren Wood, a hydrogeologist at Michigan State University and co-author of the new study.

“This is an idea that a number of us have knocked around a little bit, but I think the approach here is really novel,” said Bill Simpkins, a hydrogeologist at Iowa State University in Ames, Iowa who was not involved in the study. “[Groundwater depletion] is certainly not a documented source that people feel obligated to put in their climate estimates.”

Groundwater’s carbon cycle

Rain falling from the sky contains the same amount of carbon dioxide as is present in the atmosphere. But soil carbon dioxide levels are up to 100 times greater than carbon dioxide levels in the atmosphere, because soil microbes degrade organic carbon into carbon dioxide. When rainwater hits the ground and percolates through Earth’s rocks and sediments, the water dissolves extra carbon produced by these microbes.

If left to its own devices, this carbon-rich water remains below ground for hundreds to thousands of years before surfacing in oceans or freshwater bodies. But humans are now extracting groundwater at an unprecedented pace to sustain a growing population. The United States alone sucks up nearly 80 billion gallons (303 billion liters) of water from the earth every day to supply drinking water and irrigate crops, enough water to fill Utah’s Great Salt Lake five times every year.

Analyzing depletion’s impact

Wood’s research has largely focused on the hydrogeology of arid areas, but he recalls suddenly coming up with the concept for the new study one morning after coffee. “It came to me at about 9:30 a.m. and by 11:30 a.m. I had the first draft of the manuscript done,” Wood said.

In the new study, Wood and Hyndman analyzed groundwater depletion and groundwater carbon chemistry data from the U.S. Geological Survey (USGS) to calculate how much carbon dioxide is likely transferred from groundwater to the atmosphere each year.

USGS scientists estimate that the United States annually depletes 25 square kilometers (9.7 square miles) of groundwater, which contains roughly 2.4 million metric tons (5.2 billion pounds) of bicarbonate. Wood and Hyndman then conservatively assumed that half of the released bicarbonate is converted to atmospheric carbon dioxide.

From this information, Hyndman and Wood estimated the U.S. releases approximately 1.7 million metric tons (3.8 billion pounds) of carbon dioxide a year into the atmosphere from groundwater depletion. This is more than the amount of carbon dioxide produced by the generation of electricity used to power 250,000 households in the United States each year.

Scientists know less about groundwater depletion on a global scale, but Wood and Hyndman predict groundwater depletion releases 9.7 to 13.5 million metric tons (21.4 to 29.8 billion pounds) of carbon dioxide to the atmosphere each year globally.

“This linkage between subsurface water and the atmosphere is a very creative and original synthesis. I’m not aware of anyone who has even suggested this in the past,” said Lenny Konikow, a scientist emeritus at the U.S. Geological Survey who was not involved with the study.

The researchers note that this study is still just a preliminary step, but they hope their study will provoke in-depth research on the role of carbon dioxide from groundwater depletion.

“If we can understand how humans are having an effect, hopefully we can take that next step and try to mitigate some of these effects,” said Hyndman.

###

The paper: http://onlinelibrary.wiley.com/doi/10.1002/2017EF000586/abstract

Ok, let’s put the numbers in perspective.

The study says groundwater depletion produces 1.7 million metric tons of CO2 in the USA every year. Sounds huge, right?

The EPA says that 6,587 million metric tons of CO2 were released in the USA from all sources in 2015.

That’s 0.0258 % of the total CO2 releases for the USA in 2015. That’s also likely below the measurement error band for the EPA data, making it insignificant.

Color me unconcerned.

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Earthling2
November 16, 2017 11:55 am

“Rain falling from the sky contains the same amount of carbon dioxide as is present in the atmosphere.”

Isn’t that same amount of CO2 collected by the rain on the way down, a terrestrial source, and even if counting the additional 100 ppmv added by humans the last 150 years, it is just returning to the atmosphere where it came from? Even if we humans added the last 100 ppmv, it is counting it twice. It’s a bit like saying that we humans who each breath out a 1/2 ton of CO2 a year is adding to the CO2 in the atmosphere. No, we are just recycling CO2 that was already in the atmosphere when we first started breathing. This looks like double bookkeeping to me.

Reply to  Earthling2
November 16, 2017 1:21 pm

“No, we are just recycling CO2 that was already in the atmosphere when we first started breathing.”

That’s not true if you think about it. If all of the oxygen producing plants and bacteria died tomorrow then aerobic animals would slowly use up the atmospheric oxygen supply and replace it with carbon dioxide – while the oxidation of minerals contributed to the oxygen scavenging. Just as if all the animals died the plants would use up all of the available co2 and replace it with o2.

The cyanobacteria put oxygen in the atmosphere in the first place and the terrestrial plants added to it during the Carboniferous while removing the co2 and before the terrestrial o2 breathers had evolved. Co2 levels during the Carboniferous were dangerously low – as indeed they are today. Following the arrival of o2 breathing animals co2 levels recovered. Now fossil fuel burning is helping the co2 recovery.

So no – it isn’t just a recycling process going on but one of active chemical change.

Earthling2
Reply to  cephus0
November 16, 2017 1:51 pm

You may be correct on a 500 million year timescale cephus0, but I am just talking about the last 150 years that we have been extracting groundwater and burning CO2 in any significant amount. We humans are respirating nearly 3.5Gt (gigaton – 3.5 billion tons of CO2) just from breathing, which currently humans are supposedly adding a total of 26-30 Gt to the atmosphere by FF and land use change. We are organic beings of the good Earth and therefore part of the carbon cycle. If not, then there is way too many people just breathing since that represents more than 10% of all human produced CO2 of every kind.

Sheri
Reply to  cephus0
November 17, 2017 6:02 am

Earthing2: You would think we were part of the cycle, but it seems we are aliens or a cancer or something. We obviously did not evolve here and we should just all go away and let the earth be.

(/sarc, though I hope no one needed that tag…)

Reply to  Earthling2
November 16, 2017 2:10 pm

Earthling2,

Indeed the CO2 absorbed by rain is just part of a huge CO2 cycle: Where water is evaporating near the equator, also a lot of CO2 is leaving the surface (mainly at the deep ocean upwelling zones). Part of it returns with rain, most of it is absorbed by cold sinking waters into the deep oceans again near the poles. Overall flux about 40 GtC/year (based on 14C bomb spike decay and 13C “thinning”).
Some of that rain water aborbs extra CO2 where carbonate rock is present and either flows back to the oceans via rivers or resides in aquafers until diverting to rivers and seas or used for irrigating. The latter may -temporarely- increase CO2 levels, if there is no balance between uptake and release, as good as is the case for forest clearing and replantation…

rocketscientist
November 16, 2017 11:55 am

Is the CO2 supposedly out-gassing or is it merely contained as soluble minerals in the water? Just because rain water doesn’t carry much CO2 doesn’t mean that ground water must have much more, or that it even is being returned to the carbon cycle via ground water.

A whole lot of unsubstantiated speculation.

Nick Stokes
Reply to  rocketscientist
November 16, 2017 2:12 pm

“Is the CO2 supposedly out-gassing”
It’s basically just another way of mining carbon. There is a store in groundwater, probably more due to respiration of soil organisms than collected in rain. And we’re pumping it to the surface.

But as the post notes, the numbers are pretty small.

David A
Reply to  Nick Stokes
November 17, 2017 9:15 am

…and CO2 saves an immense amount of groundwater.

RWturner
Reply to  rocketscientist
November 16, 2017 3:03 pm

The carbon in groundwater is part of the carbonate-bicarbonate system just like in marine waters.

Reply to  rocketscientist
November 16, 2017 5:14 pm

Well, from the article,

“Wood and Hyndman then conservatively assumed that half of the released bicarbonate is converted to atmospheric carbon dioxide”.

So, not from out-gassing … primarily from conservatively assuming.

GeologyJim
Reply to  rocketscientist
November 17, 2017 7:29 am

If we’ve learned nothing else from the last 20 years, the actual data show that CO2 in the atmosphere doesn’t matter to weather or climate (plant fertilizer, Yes, but temperature, No)

Approximately 30% of all human-generated CO2 has been released in the last 20 years, while satellite-measured temperatures have not materially changed

Feynman: “If the data don’t fit the hypothesis, the hypothesis is wrong”

So who cares where CO2 originates?

Bruce Cobb
November 16, 2017 11:57 am

Hope they didn’t hurt themselves patting themselves on the back.

higley7
Reply to  Bruce Cobb
November 16, 2017 5:21 pm

It took him two hours to dream this up and then create estimates of the effects. No science performed of any kind. This is all speculative, using dubious, general, and possibly inapplicable information. Wow.

“25 square kilometers (9.7 square miles) of groundwater” Something seems wrong with this as this does not denote a volume, just and area. As I said, dubious.

As CO2 is plant food and we need more not less. his whole morning, probably some perfectly good coffee, and salary time was wasted.

Old44
Reply to  higley7
November 17, 2017 4:09 am

And 1 hour 50 minutes of that was spent calculating how big a grant he could get.

Hugs
November 16, 2017 12:00 pm

I find this awesomely baseless. Water depleted will just end up somewhere, with some CO2 in it. It is not gonna disappear. Global warming causes faster hydrologic cycle so more CO2 is taken down to seas. Color me astonished on how you can publish stuff like this.

Oh, they probably wanted just another reason to be miserable. Don’t take a shower, it has a carbonic footprint in it.

Auto
Reply to  Hugs
November 16, 2017 5:09 pm

Hugs
I agree.
“The study’s authors estimate groundwater depletion in the United States could be responsible for releasing 1.7 million metric tons (3.8 billion pounds) of carbon dioxide to the atmosphere every year.”

1 – note ‘could be’ (in the first line of the quote, for the Griffster and her/his pals).

2 – 1.7 million tons/tonnes a year [let us accept it for this thought experiment] is about 5 kilograms a year for each American, if population is 340 million [current estimate is about 325 million, so probably a 5% underestimate [but good enough for a seaman like me – round numbers, estimates – don’t even need an envelope to calculate].

3 – 5 Kg/year (~11 pounds/year) is – allowing twelve months – about – roughly – 1 pound per month per American. About.
Maybe 7-8% less, nicely balancing (for this seafarer: – “near as dammit” works for this type of simple sum) the 5% over from the population estimate above.

4 – As a first order approximation, therefore, either jogging two kilometres less, per week, OR buying two expensive coffees less per week will make up for this – roughly – one whole pound a month of extra CO2 that – apparently – ground water depletion ‘COULD’ (from the our host’s introduction) be responsible for – sorry – I have split an infinitive.
[Mods – this is pure guesswork on my behalf – but I (guess) suspect I am about in the right area to one order of magnitude.
If anyone has good data on jogging or making expensive coffee in Star*ucks or wherever, please correct me!
Thanks!]
But you get the general picture.

Then AAA) – “USGS scientists estimate that the United States annually depletes 25 square kilometers (9.7 square miles) of groundwater.”
To what depth – a micron? A millimetre? A mile?
If a direct quote form the paper – it’s 1 am, (here), I’ve drunk some wine, and I am NOT looking up the original paper now . . . – then the paper is innumerate.

Auto

PS – for occasional visitors, a quiz question.
Q To the nearest one tenth of one percent, how much CO2 is in the planetary atmosphere today – after sixty some years of ICE etc. pumping CO2 into the atmosphere?
A At 405 parts per million, it is less than half a part per thousand – so – to the nearest one tenth of one percent – the answer is zero.

And Q2 What percentage of CO2 in the local atmosphere makes farmers, arboriculturalists, fruit and veg growers, etc., happy that their crops are growing at an optimum rate?
A 2 Certainly over 800 ppm; some suggest 1200 ppm, even 1500 ppm. That last figure is over three and a half times the CO2 in the atmosphere currently.

Just asking.

Thomas Homer
November 16, 2017 12:06 pm

from the article: “If we can understand how humans are having an effect, hopefully we can take that next step and try to mitigate some of these effects,”

Can we first ascertain whether these effects caused by humans are beneficial or detrimental prior to getting started on the mitigation?

Life consumes CO2.

gunsmithkat
November 16, 2017 12:07 pm

So?

Doug MacKenzie
November 16, 2017 12:12 pm

Simple solution for snowflakes, just quit using groundwater.

AndyG55
November 16, 2017 12:14 pm

Depleting groundwater could be a problem for the future.

Adding CO2 to the atmosphere can only be a benefit to the future.

Joel Snider
November 16, 2017 12:19 pm

So – no farming, no wells. Really, no living in areas outside the city.

Tom in Florida
Reply to  Joel Snider
November 16, 2017 1:00 pm

“No phone, no lights, no motor car,
Not a single luxury,
Like Robinson Crusoe,
It’s primitive as can be.”

Now where have I heard that before?

November 16, 2017 12:29 pm

A substantial amount of natural release of CO2 may occur from subsurface rocks associated with hydrocarbon-bearing reservoirs. I have ignited natural seeps of methane bubbling up from creeks in the San Juan Basin, a major gas producing area. I wonder if any surveys of natural CO2 releases associated with hydrocarbon producing basins have been conducted.

Also, what is exactly meant by CO2 release due to ground water depletion? In the case of methane, pressure depletion of the reservoir reduces the amount of methane released from a reservoir. is the proposed CO2 release from a confined or unconfined aquifer? Would not pressure depletion from a confined aquifer reduce the amount of CO2 release? Seems to me this subject has has taken off into the wild blue yonder too soon.

D. J. Hawkins
Reply to  Tom Bjorklund
November 16, 2017 1:25 pm

They are talking about carbon bound as dissolved bicarbonates in the water, not free CO2 dissolved in the water. They are saying 50% or so of the bicarbonates are ultimately converted to CO2 after the water is pumped up from the aquifer.

NW sage
Reply to  D. J. Hawkins
November 16, 2017 5:29 pm

I didn’t see any mention of bicarbonates. But the authors also don’t seem to realize that CO2 in rain can only increase to the point of saturation – the same for ground water. The ground may contain a lot of CO2 but the water in the ground cannot hold more than the saturation amount at the temperature of interest
Accordingly, the basic assumption that rainwater contains the same amount of CO2 as the atmosphere, and increases right along with it is completely wrong. In the temperature ranges of interest here, the CO2 saturation in water INCREASES as temperature drops. That effect doesn’t seem to be accounted for either.

D. J. Hawkins
Reply to  D. J. Hawkins
November 20, 2017 1:57 pm

@NW Sage;

From the article:

USGS scientists estimate that the United States annually depletes 25 square kilometers (9.7 square miles) of groundwater, which contains roughly 2.4 million metric tons (5.2 billion pounds) of bicarbonate. Wood and Hyndman then conservatively assumed that half of the released bicarbonate is converted to atmospheric carbon dioxide.

Shawn Marshall
November 16, 2017 12:40 pm

They really nailed down that .02xx% with a WAG. Only 2 hrs from coffee to paper – now that is some real science.

Stu C
November 16, 2017 12:42 pm

Just setting us up for the next big tax grab. Did anyone really think they would stop at just taxing fossil fuels? Beside they have the signs all ready to go “Leave It The Ground”.

Latitude
November 16, 2017 12:44 pm

oooooooooooooo…big number……scary!

“1.7 million metric tons (3.8 billion pounds) of carbon dioxide to the atmosphere every year.”

reality…..no enough to even find it

Biggg
November 16, 2017 12:58 pm

But the science is settled. How could a science that is settled miss such a huge item as this? Wait.

Steve Zell
November 16, 2017 1:00 pm

“From this information, Hyndman and Wood estimated the U.S. releases approximately 1.7 million metric tons (3.8 billion pounds) of carbon dioxide a year into the atmosphere from groundwater depletion.”

That sounds like a lot, but the U.S. total human emissions of CO2 are estimated at 6 Billion metric tons per year. So the CO2 from groundwater depletion would be less than 0.03 percent of the total human emissions, or a proverbial drop in a bucket.

“The United States alone sucks up nearly 80 billion gallons (303 billion liters) of water from the earth every day to supply drinking water and irrigate crops, enough water to fill Utah’s Great Salt Lake five times every year.”

Another instance of trying to make something seem larger than it is. The Great Salt Lake has a relatively large area (4,400 km2) but its volume is 18.92 km3, which results in an average water depth of only 4.3 meters, or about 14 feet.

If the 303 billion liter per day figure for the entire United States is accurate, this comes out to about 110.6 billion cubic meters of water per year. Dividing this by the area of the 48 contiguous states (8.08 million km2 = 8.08 trillion m2) results in an average drawdown depth of 0.0137 meter, or 1.37 cm, or about 0.54 inch of groundwater depth per year.

With most areas of the United States receiving between 10 and 60 inches of rainfall per year, it’s quite possible that the half inch of drawdown could be replenished by seepage of rainwater into the aquifers.

D. J. Hawkins
Reply to  Steve Zell
November 16, 2017 1:27 pm

With most areas of the United States receiving between 10 and 60 inches of rainfall per year, it’s quite possible that the half inch of drawdown could be replenished by seepage of rainwater into the aquifers.

It could be, but in practice it isn’t.

Michael Jankowski
Reply to  Steve Zell
November 16, 2017 4:34 pm

The groundwater usage numbers match what USGS estimates and is probably their source for the numbers. Dividing across the 48 contiguous states is nonsense, however.

About 75% of the US water supply is surface water. All except for about 10 states withdraw less than 2,000 Mgal/day in groundwater. Fives states – CA, AR, TX, NE, and ID – currently make up about half of the withdrawal rate. The Ogallala Aquifer critical to the Great Plains has dropped by up to 300 ft in some locations and up to 5 ft in single years. It is replenished by rainfall to varying extents depending on location but averages about 1 in/yr. If it were completely barren, it would take 6,000 yrs of rainfall to be replenished.

RACookPE1978
Editor
Reply to  Michael Jankowski
November 16, 2017 6:50 pm

Good numbers, but I ask you spend a few minutes and separate the critical aquifers (TX Bandera-Edwards Aquifer, upstate TX-Plano are very far apart) and the very important Ogallala region (many more states than NB!) from each other area.
Idaho ?
CA I thought almost used no aquifer water, but billions of tons of Sierra Mtn runoff/dammed water/Colorado river water.

Michael Jankowski
Reply to  Michael Jankowski
November 17, 2017 10:14 am

Idaho doesn’t have a large population, but it has pretty minimal surface water supplies and has a thirsty agricultural portion to its economy.

California is dependent on groundwater for 30-50% of its needs.

TX aquifers are discussed here http://texasalmanac.com/topics/environment/aquifers-texas , albeit without much data.

Allan MacRae
Reply to  Michael Jankowski
November 17, 2017 10:44 am

The problem is NOT CO2 and NEVER WAS.
The problem IS groundwater depletion, especially of the critical Oglala aquifer in the USA, which is dropping rapidly.
Stop corn ethanol fuel production – that is part of the solution.

November 16, 2017 1:02 pm

The lake at the La Brea tar pits about 6 miles west of downtown Los Angeles is a place where methane gas is bubbling 24/7.

Moderately Cross of East Anglia
November 16, 2017 1:11 pm

It’s a wonder any living thing is left alive on this planet with this never ending litany of eco-geddon these people trot out. I am seriously coming to the conclusion the greens and eco-warriors are in need of treatment for a severe form of paranoia which renders them incapable of living happy and well adjusted lives, especially when they think there is some fossil fuel conspiracy at play to kill us all. Really? Another day, another doom story. Yawn!
Just as well the vast and growing majority of people are not buying their narrative. Oh I forget, anyone who doesn’t is stupid, deplorable or non-pc (perhaps all three).

November 16, 2017 1:15 pm

But what about all the extra Water Vapour that is added to the atmosphere because of irrigation!?
Giga tonnes of a potent ‘GHG’ just ‘dumped’ into the atmosphere every year…and no one says a thing about it. Truly terrifying.

Latitude
Reply to  Charles Gerard Nelson
November 16, 2017 1:20 pm

………it’s a twofer

Reply to  Charles Gerard Nelson
November 16, 2017 2:46 pm

Oh come on Charles, you know it only matters if it’s CO2. From fossil fuels. Haven’t you learned the message yet?

(/sarc cause there’s a few humourless commenters out there)

BallBounces
November 16, 2017 1:30 pm

Any society that doesn’t promise to be water-free by 2050 is anti-science.

November 16, 2017 1:48 pm

Just another example of how grant-hungry scientists see opportunity to climb on-board the Climate gravy train.

tadchem
November 16, 2017 2:30 pm

OMG! Perrier is killing the planet!

RWturner
November 16, 2017 2:51 pm

Color yourself unconcerned, I’ll cover myself a rosy red from LoL.

They assume: “On exposure to the atmosphere, the groundwater will reequilibrate with the atmosphere releasing CO2 and precipitating calcite…Using a conservative assumption that upon reentry of the groundwater to the surface, half of the bicarbonate (95 mg/L) in groundwater is converted to CO2.”

Is this assumption backed up or refuted by empiricism? Well, it’s a big NO, that assumption is laughably refuted by empiricism. Where to start?

First of all, if half of the dissolved carbonate precipitated into calcite and CO2 released into the atmosphere, all of of the world’s irrigated farmland would be nothing but a thick salt crust (someone check if this has happened). Crusting can be a problem with irrigation, but it’s been well known and mitigated in the industrialized world for a long time. Enough water is used and infiltration methods employed that allow the water to seep into the saturated soil zone, taking the salts and dissolved carbon with it.

But how about the water that doesn’t seep in and instead runs off? Is the water in the fluvial system at equilibrium with the atmosphere, i.e. is rainwater chemistry the same as river water? NOOP. Trillions of tons of dissolved load enters the oceans from rivers each year, this dissolved load did not fall within rainwater, and the pH of river waters at their mouths are typically ~8.0-8.2 whereas rainwater is typically ~5.6. This pH difference is mostly from bicarbonate in the water.

Well okay, but what happens as groundwater discharge is evaporated and leaves half of the dissolved load behind as precipitates? If this were the case, we’d directly observe half of all dissolved salts being deposited at the mouth of natural springs and within cave systems. Instead, travertine and other precipitate deposits are quite rare.

Typical groundwater discharge deposits occur due to a change in saturation state due to pore pressure decrease once the water is discharged, depositing well under 50% of the dissolved load. Essentially, half of all dissolved limestone would be redeposited as speleothems with the cave if their assumption were correct. The largest travertine deposits do not occur from aquifer discharge but from geothermal water where an even larger pressure decrease and typically a temperature induced pH increase occurs.

This assumption is almost as bad as the thawing permafrost leads to a net carbon discharge meme. I’m still waiting for how they propose the carbon was sequestered in permafrost in the first place.

Some quick dirty math for consideration on how much precipitated limestone deposits we’d need to see just from karst terrains in the last 10,000 years:

196.9M mi^2 * 13% karst surface = 26M mi^2 karst surface area * conservative estimated denudation rate of 10mm/1kyr (0.0000625mi/10,000yr) = ~1,600 * 50% = 800 cubic miles of cool water limestone precipitate in the past 10,000 years

RWturner
Reply to  RWturner
November 16, 2017 3:00 pm

If that limestone precipitate were spread 1 foot thick, it would be 2,057 miles on each side. Enough to cover the entire U.S. in 1 foot of limestone and have about 500,000 square miles left over.

Tom Bakewell
November 16, 2017 3:17 pm

Once again the AGU makes me somewhat embarrassed to be a geophysicist. In my defense I worked for a living by finding ‘stuff’ instead of fishing for grants. Arrrggghhh!

Gary Pearse.
November 16, 2017 3:47 pm

Humans are doing this. Humans are doing that. I reckon ONLY humans are exploiting groundwater. The use of this type of rhetoric is to underscore the evil of humans. Oh, and Dave, 1/3000th of the amount emitted from fossil fuels in the US IS the definition of insignificant. That you thought about it at 9:30 and had this worthless paper finished by 11:30, also screams out insignificant. There are 600coal fired electrical plants in the US. We could accommodate your gassy water by shutting down ~1/2 of a coal plant!

At least you couldn’t have had a grant for this coffee break to lunch effort.

November 16, 2017 4:02 pm

…and in an attempt to falsify this shiny new theory, Wood and Hyndman sampled groundwater from wells evenly distributed across the US, and accurately measured the pH levels, and amount of carbonic acid by volume.

..right?

November 16, 2017 4:07 pm

Claim: groundwater depletion releases ‘significant’ carbon dioxide

Significant?
Significant to what?
Most of the water plants in the US (not sure about the rest of the world) are ground water plants.
The “War on Coal” wasn’t enough (an is loosing traction) so they open a “War on Water”?

PS Are they going to shut down Perrier? (Probably not. Too close to Paris.)

Non Nomen
Reply to  Gunga Din
November 16, 2017 11:40 pm

The “EU” intends to ban CO2 from Champagne, sparkling wines and other beverages for the sake of Gaia?

Reply to  Gunga Din
November 17, 2017 2:40 pm

Just to be clear.
When I said, “Most of the water plants in the US (not sure about the rest of the world) are ground water plants.”, I did not mean that most of the US population gets it’s water from ground water plants.
Most water plants in the US are ground water plants but the populations they serve are small.

Michael Jankowski
November 16, 2017 4:08 pm

“…Wood and Hyndman then conservatively assumed that half of the released bicarbonate is converted to atmospheric carbon dioxide…”

How about some actual data instead of a magical “50%” and claiming it is “conservative?”

November 16, 2017 6:00 pm

Don’t breathe.

Don’t drink.

Don’t have babies.

BUT FOR GOD’S SAKE, BUY BITCOIN !!!

Joey
November 16, 2017 6:46 pm

Isn’t it strange that everything connected to “climate change” is negative? I think that is the hallmark of propaganda.

Ellen
November 16, 2017 7:15 pm

Groundwater depletion is a bad idea, and New Orleans is the poster child. The CO2 is just another way for the warmists to say “anthropogenic”.

Reply to  Ellen
November 17, 2017 7:21 am

It depends completely where the depletion is, what the recharge is likely to be and what use the water is put to. The water’s content of CO2 is a meaningless detail.

Steve Oregon
November 16, 2017 7:46 pm

“Humans may be…..”

The the absence of drought lessens the worry about depletion.
comment image?itok=_YETDLxz&hash=1442b093

JBom
November 16, 2017 8:18 pm

Just in from the Greatest Most Significant Human Being Ever Born Christine McEntee of the Gad Awful AGU. “Shitting In Water Causes Great Increase of CO2 And Is Irreversible!”

Oh! Well then.

Karl Baumgarten
November 16, 2017 8:50 pm

Groundwater recharge just puts it all back in the ground.

Non Nomen
November 16, 2017 11:36 pm

Just one of many attempts to come to fabricate pretences for taxing water heavily.

paqyfelyc
November 17, 2017 2:41 am

Well, at least this dumbo allowed a couple good jokes, including

BallBounces
Any society that doesn’t promise to be water-free by 2050 is anti-science.

tadchem
OMG! Perrier is killing the planet!

And really, this is all this stuff deserves. Ridicule.

michael hart
November 17, 2017 7:25 am

Rain falling from the sky contains the same amount of carbon dioxide as is present in the atmosphere.

Not necessarily. The statement is probably wrong for both kinetic and thermodynamic reasons. The interconversion of carbonate and CO2 is far slower than a diffusion-controlled chemical reaction. This is why all of creation uses carbonic anhydrase to speed up the reaction ~10,000,000 fold.

And what I defy any person to show me, is the solubility of CO2 in supercooled water particles in clouds at, say, -30 Celsius. Yes, that is way below the freezing point of water, and the solubility of CO2 starts rising hugely as the temperature approaches zero degrees. It probably means that rainfall scrubs CO2 from the atmosphere more efficiently than the models assume, if they treat the matter at all.

Oakwood
November 17, 2017 8:08 am

I just saw this posted on LinkedIn. As I work in the environmental sector, many of my contacts are also in that field. Too many of them are communicators and ‘thought leaders’ rather than doers. Many post up any climate change doom story they come across. As long as the headline says ‘CC is worse than we thought’, it fits the bill. They think they are so clever for keeping up with the news! I really have to grit my teeth to not post a reply. In my sector, if I don’t keen stum with my real thoughts on CC alarmism, it would damage my work prospects.

getitright
November 17, 2017 12:01 pm

“It’s not going to change the way we think about global climate change….”
He said while attempting to change the way we think about climate change.
Fortunately for me, to no avail.

November 17, 2017 2:17 pm

so tired of published studies with no conclusions. pan handling “science”.

Every single flipping “muh CO2” paper has no conclusions, just mights and maybes

Junk science, science is in crisis, too many hacks in all fiellds

Reply to  Mark - Helsinki
November 17, 2017 3:02 pm

Maybe a bit too strong.
Lot’s of scientist, theologians, engineers, etc. get something wrong. Honestly.
What makes them a “hack” is selling out to the big $green$ carrot. (Or selling out to ideology. “The end justifies the means.” kind of stuff.)
But, yes, there are too many hacks in all fields. Some in those fields are just victims of the “hackers”.
Be skeptical. Return to the source.
(As far as a theologian goes,
Acts 17:11 These were more noble than those in Thessalonica, in that they received the word with all readiness of mind, and searched the scriptures daily, whether those things were so.
Not a bad approach whatever field you are in.)

November 17, 2017 9:04 pm

IIRC, a research project on the other side of the world a couple of years ago came to the opposite conclusion; Ground water use took a large amount of CO2 from the atmosphere.

Michael Darby
November 18, 2017 4:02 am

The more carbon dioxide the better. Every little bit helps