Earth’s Oceans Forged from Dry Pebbles: Lab Experiments Show Rocky Planet Grew Its Own Water

New research from the University of New Mexico suggests Earth produced much of its water during its formation through chemical reactions between rocky material and a hydrogen- rich atmosphere, rather than (or in addition to) receiving it mainly from external sources like comets or meteorites.
The pebbles didn’t bring water; they made it chemically while falling through Earth’s early atmosphere.
The newly formed water vapor could later condense into oceans (or dissolve into the magma ocean and be released later), while the metallic iron sank toward the core.

An artistic depiction illustrating Earth's formation, showing dry silicate pebbles falling through a hydrogen-rich atmosphere, with labels detailing the processes of melting and reaction that lead to water vapor forming oceans.
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New research from the University of New Mexico suggests Earth produced much of its water during its formation through chemical reactions between rocky material and a hydrogen- rich atmosphere, rather than (or in addition to) receiving it mainly from external sources like comets or meteorites.

The study, published in Nature Geoscience (around October 2026), was led by graduate student Susmita Garai with professors Zachary Sharp (director of Earth and Planetary Sciences) and Peter Olson.

It focuses on “pebble accretion”, in which small rocky particles (“pebbles”) build up a growing planet. Once the planet becomes massive enough, it can hold a hot, high- pressure, hydrogen- rich atmosphere. As iron- bearing silicate pebbles fall through this atmosphere (“pebble rain”), iron oxide in the rocks reacts with hydrogen to produce metallic iron and water vapor.

Researchers heated silicate rock samples to 1,200- 1,400°C in streams of hydrogen (and, for comparison, helium) for 15 minutes to 3 hours, simulating early planetary conditions.

In the hydrogen experiments, nearly 80% of the iron oxide converted to metallic iron, generating water vapor. The reaction did not occur in helium, confirming hydrogen’s essential role. Extrapolation of the results indicates that hundreds of oceans’ worth of water could have formed this way.

Sharp noted that previous ideas relied on external delivery, but “virtually any Earth- sized planet should have water by this newly identified mechanism”. Water forms rapidly (in minutes under these high- temperature conditions), and the process could help explain Earth’s habitability.

This mechanism does not require all of Earth’s water to arrive as ice or water-rich materials from farther out in the solar system. It could operate on other Earth- sized rocky exoplanets that form under similar conditions with hydrogen atmospheres, making water (and potentially life) more common.

Pebble accretion itself is a relatively recent idea (last decade or so) that addresses several issues in traditional planet- formation models.

The researchers emphasize that while the experiments demonstrate a viable pathway, further work is needed to determine how much of Earth’s actual water inventory came from this process versus other sources. This adds to ongoing scientific discussion about Earth’s water origins, which has included contributions from nebular hydrogen, magma- ocean interactions, and later deliveries.

A fiery landscape depicting a molten surface with meteors streaking through a fiery sky, illuminated by a bright sun.
Pebble rain. Credit: The University of New Mexico

The pebbles didn’t bring water; they made it chemically while falling through Earth’s early atmosphere.

Here’s the step- by- step process according to the 2026 Nature Geoscience experiments (Garai, Sharp, Olson & Gargano):

1. The setting

As the young Earth grew by pebble accretion, it pulled in millimetre- to centimetre- sized dry silicate pebbles (rocky particles rich in iron oxide, FeO). Once the planet became massive enough, it held onto a thick, hot, hydrogen-rich (H₂) atmosphere captured from the solar nebula. Temperatures near the base of this atmosphere were high enough to melt the falling pebbles (above the silicate melting point, roughly 1,200- 1,400 °C in the experiments).

2. The chemical reaction

As the molten pebbles settled through the hydrogen atmosphere, a redox reaction occurred:

FeO (in the silicate melt) + H₂ (gas) → Fe (metallic iron) + H₂O (water vapor)

  • Hydrogen stripped oxygen from the iron oxide in the rock.
  • That oxygen combined with more hydrogen to form water vapor.
  • Metallic iron was left behind.

Lab experiments showed this reaction is fast and efficient: in just minutes to a few hours, up to ~70–80% of the iron oxide in the samples was converted into metal, producing measurable water vapor.

3. Scaling it up

Because vast numbers of pebbles rained onto the growing Earth over millions of years, the cumulative effect was enormous. Extrapolation of the experimental results suggests this process could have generated hundreds of oceans’ worth of water.

The newly formed water vapor could later condense into oceans (or dissolve into the magma ocean and be released later), while the metallic iron sank toward the core.

Key takeaway

Earth’s oceans weren’t delivered ready- made by icy comets or asteroids in this model. Instead, dry rocky pebbles and a hydrogen atmosphere and heat produced the water in place during the planet’s assembly. This makes water formation a natural byproduct of how Earth- sized rocky planets grow.

Scanning electron microscope images showing surface morphology of materials annealed at 1,300 °C for 3 hours (a) and 1,250 °C for 1 hour (b), with scale bars of 50 µm.
a) This scanning electron microscope image shows rounded metal droplets formed through heating phosphorus-containing rock in a hydrogen atmosphere at 1,300°C for three hours. The spherical shape indicates that the metal melted, even though the temperature was below the melting point of pure iron (1,538°C). b, In contrast, after one hour of heating a phosphorus-free sample at 1,250°C, the iron oxide is reduced to solid iron crystals rather than rounded droplets. Credit: Nature Geoscience (2026). DOI: 10.1038/s41561-026-02118-7

Experimental simulation of water formation on Earth from dry pebble rain

“Experimental simulation of water formation on Earth from dry pebble rain” is a 2026 paper in Nature Geoscience by Susmita Garai, Zachary D. Sharp, Peter L. Olson, and Anthony M. Gargano (primarily University of New Mexico, with affiliation to the Lunar and Planetary Institute). DOI: 10.1038/s41561-026-02118-7.

It experimentally tests the idea that much of Earth’s water formed in situ during planetary growth via pebble accretion, rather than (or in addition to) being delivered later by water- rich asteroids or comets.

Core hypothesis

In the pebble accretion model, a growing proto-Earth accretes millimetre- to centimetre-sized silicate “pebbles.” Once the body is massive enough, it retains a thick, hot, H₂-rich primordial atmosphere captured from the solar nebula. Basal temperatures in this atmosphere exceed the silicate liquidus, so falling pebbles melt as they settle through it. Iron oxide (FeO) in the molten silicate reacts with atmospheric hydrogen:

FeO (in silicate) +H2 ​→ Fe (metal) + H2​O (vapor)

This produces water vapor while reducing iron oxide to metal. The process is rapid (minutes to hours under experimental conditions) and can generate large quantities of water endogenously.

Experimental methods and results

The team melted anhydrous (water- free) samples of mid- ocean ridge basalt (MORB), picrobasalt, and synthetic MORB in flowing hydrogen gas streams at 1,200- 1,400 °C (and control experiments in helium). Run durations ranged from 15 minutes to 3 hours.

Key outcomes:

  • A substantial fraction of FeO (up to ~70- 80% under optimal conditions) was reduced to iron- rich metal, generating water vapor.
  • Moderately volatile elements such as Na and S evaporated from the melt.
  • The newly formed metal strongly sequestered phosphorus, stripping it from the silicate.
  • No comparable reduction occurred in helium, confirming the role of hydrogen.

Extrapolation suggests this mechanism could produce hundreds of oceans’ worth of water during Earth’s formation. The metal would eventually sink to the core, helping explain Earth’s mantle Fe/Mg ratio and its relatively low phosphorus content compared with Mars.

Broader implications

  • Provides a massive endogenous (internally generated) water source that does not require delivery of icy material from beyond the snow line.
  • Aligns with pebble accretion solving several compositional and timing issues in terrestrial planet formation.
  • Suggests Earth- sized exoplanets that form via pebble accretion in hydrogen-rich environments could routinely inherit substantial water inventories, aiding habitability.

The authors note that while the experiments demonstrate an efficient water-producing pathway, quantifying the exact contribution to Earth’s present- day water budget (surface oceans plus mantle reservoirs) requires further modeling and constraints (including isotopic considerations such as D/H ratios after later hydrogen loss). The work adds a chemically grounded alternative or complements to traditional exogenous delivery models.

Journal: Nature Geoscience, (2026)

DOI: 10.1038/s41561-026-02118-7

Provided: University of New Mexico

Published: 24 September 2026

Authors: Susmita Garai,
Zachary D. Sharp,
Peter L. Olson &
Anthony M. Gargano

Abstract

Water is vital to planet habitability. However, the sources of water for terrestrial planets and timing of delivery remain controversial. Here we show experimentally how oceans of water can be produced within the high-temperature H2-rich atmosphere above a terrestrial planet growing by capture of millimetre-to-centimetre-size silicate pebbles. We simulate this process by melting anhydrous mafic lithologies in H2 streams. Measurements show large amounts of water generated by hydrogen reduction of iron oxide to iron metal within several hours. We also find that the produced metal strongly sequesters phosphorus, stripping it from the silicate. Our experimental results imply that silicate pebbles settling through a hot H2-rich atmosphere experience volatile loss, iron reduction to iron metal and H2O vapour production. Transfer of this metal to the core offers an explanation of the low phosphorus content of Earth’s mantle relative to Mars as well as the low Fe/Mg ratio of Earth’s primitive mantle. Atmospheric reduction of iron oxide under pebble accretion represents an endogenous source of water, and Earth-sized exoplanets built from pebbles may inherit oceans of water this way, representing a step towards habitability.

Where did Earth’s water come from?

Infographic titled 'Where Did Earth's Water Come From?' illustrating the origins of Earth's water from molten infancy to modern oceans, including key milestones like the Young Sun, Young Molten Earth, and the role of asteroids and comets.
AI generated by Grok

Earth’s water most likely came from a combination of sources, with no single definitive answer yet.

The leading ideas involve delivery by water- rich asteroids (and lesser contributions from comets), inheritance from the planet’s original building blocks, and or endogenous production during formation.

The early inner Solar System was hot, so free water or ice would have been vaporized and lost. Scientists therefore look at isotopic ratios, especially deuterium- to- hydrogen (D/H), plus the total water budget (oceans plus substantial amounts in the mantle and possibly the core) and the timing of liquid water’s appearance (evidence from zircons indicates it existed by ~4.4 billion years ago).

Main Hypotheses

Asteroid (and minor comet) delivery

Carbonaceous chondrite meteorites (especially CI and CM types, linked to outer- asteroid- belt C- type asteroids) have D/H and other isotopic ratios that closely match Earth’s oceans.

Samples from asteroids Ryugu (Hayabusa2) and Bennu (OSIRIS-REx) reinforce this chemical similarity. Dynamical models show that giant- planet growth and migration could have scattered water- bearing planetesimals inward during Earth’s accretion.

Comets were once favored but generally show higher D/H ratios; some recent measurements are closer, yet they are still considered a secondary source at best.

Inheritance from building materials

Enstatite chondrites, thought to represent much of the material that formed Earth, contain enough hydrogen (often bound in minerals or organics) to account for several times the mass of the present oceans.

Some studies argue that Earth accreted substantial water locally or retained it through the Moon- forming impact, reducing the need for a later “veneer” of outer- Solar- System material.

Endogenous production during planet formation

Laboratory experiments (published around 2025- 2026) show that hydrogen-rich atmospheres reacting with magma oceans or iron- oxide- bearing rocks can rapidly generate large quantities of water. In high- temperature, high-pressure tests that mimic early- Earth conditions, iron oxide is reduced to metal while water vapor forms efficiently, potentially enough for hundreds of ocean equivalents.

This process could operate on many rocky planets and does not require external delivery. Complementary models explore “pebble rain” or hydrogen dissolution into silicate melts.

Current Picture

Most researchers view the sources as complementary rather than mutually exclusive.

Asteroids remain a strong candidate for a major fraction of the surface and near- surface water on isotopic grounds, while endogenous reactions and original building- block hydrogen can readily supply the rest (and help explain water in the deep interior).

The exact proportions are still debated, and ongoing sample analyses plus exoplanet observations continue to refine the picture.

In short, Earth did not form completely dry and then receive all its water in a single late delivery; water was incorporated, generated, and/or delivered throughout the planet’s assembly.

Aldi ditched plastic bags: Does that actually help the environment?

In January 2024, Aldi announced the removal of plastic shopping bags at more than 2,300 U.S. stores by the end of 2023 as part of an overarching goal to “be the most sustainable grocer in the country.” The company pointed to the nearly nine million pounds of plastic the decision would save annually. It sounds impressive, and most shoppers probably take that figure at face value.

Entrance of an ALDI supermarket with shoppers entering.
Warsaw, Poland. 3 March 2026. The underground passage hall at Warszawa Zachodnia train station. Neon sign with the inscription: Aldi.

From CFACT

By Melanie Collette

In January 2024, Aldi announced the removal of plastic shopping bags at more than 2,300 U.S. stores by the end of 2023 as part of an overarching goal to “be the most sustainable grocer in the country.” The company pointed to the nearly nine million pounds of plastic the decision would save annually. It sounds impressive, and most shoppers probably take that figure at face value.

But I have a few questions.

What are customers using instead?

How much material goes into making those replacements?

And are we actually reducing waste, or just changing what people buy?

Plastic grocery bags often do more than carry groceries. People reuse them in various ways from lining small trash cans to picking up after their dogs. Without them, shoppers may buy bags for those jobs, plus paper or reusable bags to get their groceries home. Making and shipping those replacements takes materials and energy, too. Aldi should count that before claiming an environmental win.

Here in New Jersey, we have reason to ask those questions.

Following New Jersey’s May 2022 ban, Freedonia Custom Research reported that plastic consumption associated with shopping bags had nearly tripled, even as the number of bags used fell by more than 60%.

The Freedonia report estimated that most replacement bags in New Jersey were reused only two or three times before being discarded. It also reported that non-woven polypropylene bags used substantially more plastic per bag than the lightweight bags they replaced.

The report was commissioned by the American Recyclable Plastic Bag Alliance, a plastic-bag industry group. Its estimate of bag reuse came from market data rather than tracking shoppers’ habits. Travis Wagner, a professor emeritus at the University of Southern Maine, questioned its data sources and reuse estimate and noted that it had not been peer-reviewed. Those limitations deserve acknowledgment. So, does the underlying question: How often are shoppers using these bags? Calling a bag reusable doesn’t tell us whether people reuse it enough to reduce its environmental impact.

Further, a 2019 peer-reviewed study by economist Rebecca Taylor found that when plastic grocery bag use fell by about 40 million pounds a year, purchases of plastic trash bags rose by roughly 12 million pounds. The result was a 120% increase in the sale of small trash bags and a 64% increase in the sale of medium-sized bags. In other words, consumers bought back about 30% of the weight of the grocery bags eliminated in the form of new trash bags they would not have had to purchase.

Paper and reusable bags raise questions, too. Making paper bags takes materials and energy. They’re also much heavier than lightweight plastic bags, which adds to emissions from shipping them. Cotton has to be grown, watered, and processed into fabric, all of which takes resources. And polypropylene bags are still plastic. These bags have environmental costs, too.

A 2011 lifecycle assessment by Britain’s Environment Agency helps put the trade-offs in perspective. It estimated that a paper bag needed to be used three times, a non-woven polypropylene bag 11 times, and a cotton bag 131 times to have a lower global-warming impact than a conventional plastic bag used just once. That comparison assumed the plastic bag wasn’t reused as a trash liner.

Those estimates apply to the bags and assumptions examined in that assessment. They aren’t a universal rule for every bag on the market, and they concern global-warming impact rather than every environmental measure. But they make a practical point: A reusable bag has to be reused enough to justify the resources that went into making it.

Aldi says it eliminated nine million pounds of plastic. But what are shoppers using instead? An independent study, with the results made public, could show whether the switch actually reduced waste and emissions. If it did, Aldi would have a stronger case, and shoppers would have more than the company’s word for it.

Finally, there is an economic lesson here. People still need bags, even when stores stop selling them. Rebecca Taylor’s 2019 study found that shoppers bought more trash bags after grocery bag restrictions took effect. If you used those grocery bags for your trash, you now have another item on your shopping list. That expense matters, especially to families watching every dollar.

Aldi is free to choose which bags it sells. But its environmental claims deserve the same scrutiny as any other sales pitch designed to positively influence their consumer base. Greater transparency should include factors that influence how much the removal of plastic bags really affects reduced waste and emissions overall. Until then, nine million pounds tells us how much plastic Aldi stopped selling, not how much better off the environment is as a result.

Earth’s Climate Thermostat Flipped During the Age of Pangea

A University of Chicago- led study (published in Nature Communications in 2026) suggests Earth’s long- term climate “thermostat”, driven by silicate weathering that regulates atmospheric CO₂, operated primarily in a temperature- dominated mode for most of the past ~480 million years, but briefly switched to a hydrology (water and rainfall)- dominated mode during the Pangea supercontinent era (~295- 200 million years ago), then switched back.

Infographic illustrating the shift in Earth's climate control from temperature regulation to hydrology control during the Age of Pangea, featuring diagrams of CO2 outgassing, carbon uptake, and the water cycle.
AI generated by Grok

A University of Chicago- led study (published in Nature Communications in 2026) suggests Earth’s long- term climate “thermostat”, driven by silicate weathering that regulates atmospheric CO₂, operated primarily in a temperature- dominated mode for most of the past ~480 million years, but briefly switched to a hydrology (water and rainfall)- dominated mode during the Pangea supercontinent era (~295- 200 million years ago), then switched back.

Earth has stayed habitable for billions of years partly because of negative feedback in the carbon cycle. Atmospheric CO₂ reacts with rainwater to form a weak acid that weathers silicate rocks; the dissolved minerals and carbon wash into oceans and eventually form carbonate rocks.

Over geologic time these are subducted, and volcanoes return CO₂ to the atmosphere. Faster weathering cools the planet (by drawing down CO₂); slower weathering allows CO₂ to build up and warm it.

Scientists have long debated whether temperature (chemical reactions speed up when warmer) or hydrology (the amount of water available to dissolve and transport minerals) is the main control on weathering rates. The water-limited (hydrologic) mode is considered a weaker, less efficient thermostat that could permit larger climate swings while still balancing carbon fluxes.

R.J. Graham (first author, UChicago postdoc), with colleagues including Dorian Abbot and B.B. Cael (UChicago) and collaborators from the University of Southampton, ran ~120 climate- model simulations that were identical except for randomly generated continent layouts. They calculated weathering under both temperature- driven and hydrology- driven assumptions and looked for geographic “fingerprints”:

  • Temperature- controlled weathering correlates with the amount of land in the tropics (hotter but not necessarily wetter, because extra rain can evaporate).
  • Hydrology- controlled weathering correlates with how fragmented or consolidated the continents are (more coastlines and runoff favor greater water availability).⁠

Because stronger weathering cools the climate, each mode predicts an anti-correlation between global temperature and its controlling geographic variable.

The team then compared a 480- million- year temperature reconstruction with paleogeographic maps of ancient continents.

For most of the interval, temperatures anti- correlated with tropical land fraction, consistent with temperature- dominated weathering.

For roughly 100 million years overlapping the existence of Pangea, the pattern flipped to anti- correlation with continental fragmentation (i.e., the hydrology signature). The researchers attribute this to Pangea’s extensive arid interior, which limited water flow through soils so that water availability, rather than temperature, became the primary limit on weathering.

The modeling used idealized conditions (no mountain ranges, varying rock types, vegetation, etc.), relied on particular paleogeographic reconstructions, and assumed relatively steady volcanic CO₂ output. Ancient soil records from the Pangea interval could help test the idea further.⁠

If the thermostat can switch modes, it has broader relevance: a less efficient (hydrology- limited) feedback could affect the width of the “Goldilocks” (habitable) zone around stars, because the CO₂- weathering feedback is a key assumption in defining the range of orbits where liquid water, and potentially life, can persist.⁠

The paper is “Paleogeographic controls on Phanerozoic weathering rates and implications for climate regulation” (Graham, Cael, Fu, Abbot et al., Nature Communications, 2026; DOI: 10.1038/s41467-026-77289-3), with NASA funding. The University of Chicago News piece summarizing it was written by Maureen Searcy.

A grid of eight global maps displaying hydrology-controlled weathering, showcasing variations in TLF (Total Landscape Fragmentation) values and corresponding weathering fluxes in Tmol yr-1. The maps illustrate an increase in TLF from 0.16 to 0.42 and varying fragmentation levels. A color gradient indicates weathering flux intensity.
Fig. 1: Example continental configurations and hydrology-controlled weathering outputs from the global climate model (GCM) ensemble. | Nature Communications | Nature Communications

Pangea’s vast arid interior limited water availability, which made silicate weathering primarily hydrology- controlled (limited by water supply) rather than temperature- controlled.

In the UChicago- led study, this aridity is the proposed reason the climate “thermostat” briefly switched modes for roughly 100 million years while the supercontinent existed.

With much of the landmass far from ocean moisture sources, large interior regions experienced low rainfall and reduced water flow through soils. As a result, water (or the lack of it) became the main limiting factor on the chemical breakdown of silicate rocks that draws down atmospheric CO₂, rather than reaction rates speeding up with heat.

This hydrologic limitation produces a weaker, less efficient negative feedback than temperature- driven weathering. It is consistent with the geologic temperature record showing an anti- correlation with continental fragmentation (rather than tropical land area) during the Pangea interval.

Broader paleoclimate context supports the idea of an arid interior: the supercontinent’s size created strong continental climates with extensive deserts, extreme seasonal contrasts, and limited moisture penetration inland, even while coastal and equatorial margins could be wetter.

A grid of world maps showing temperature-controlled weathering with varying TLF (Temperature Limiting Factor) values and fragmentation levels. Each map illustrates weathering flux, indicated in Tmol yr-1, with a color gradient representing different flux values.
Fig. 2: Example continental configurations and temperature-controlled weathering outputs from the global climate model (GCM) ensemble. | Nature Communications | Nature Communications

Paleogeographic controls on Phanerozoic weathering rates and implications for climate regulation

Earth’s long- term climate stability is widely attributed to negative feedback from silicate weathering, which consumes atmospheric CO₂ faster as the climate warms.

A key uncertainty remains: is this feedback driven primarily by temperature (kinetic control on mineral dissolution rates) or by hydrology (runoff and water flux through the weathering zone)?

The authors ran a large ensemble of idealized global climate model (GCM) simulations that were identical except for randomized continental configurations. They then calculated global silicate weathering rates under two end-member assumptions:

  • Temperature- controlled weathering (exponential dependence on temperature, no direct runoff dependence)
  • Hydrology- controlled weathering (linear dependence on runoff, no direct temperature dependence)

They identified distinct geographic “fingerprints”:

  • Temperature- controlled weathering correlates strongly with tropical land fraction (TLF; land between 15°N/S).
  • Hydrology- controlled weathering correlates strongly with continental fragmentation (continental perimeter divided by area).

Because stronger weathering draws down CO₂ and cools the planet, each regime predicts an anti- correlation between global mean surface temperature (GMST) and its controlling geographic variable.

They compared a 480- million- year GMST reconstruction with paleogeographic reconstructions:

  • For most of the past 480 million years, GMST is anti- correlated with tropical land fraction → consistent with temperature- dominated control.
  • From roughly 295 to 200 million years ago (overlapping the existence of the supercontinent Pangea), the relationship flips: GMST becomes anti- correlated with continental fragmentation → consistent with hydrology-dominated control.
  • After ~200 Ma the temperature- controlled signature returns.

The authors suggest Pangea’s extensive arid interior reduced water availability across large areas of land, so that runoff (or the lack of it) became the primary limit on weathering rates rather than temperature.

Implications and caveats

  • The hydrology- limited regime is a weaker thermostat, potentially allowing larger climate swings.
  • The result relies on assumptions including relatively steady volcanic outgassing, a tight CO₂- temperature link, and the accuracy of paleogeographic reconstructions.
  • The GCM experiments are idealized (flat topography, no mountains, uniform lithology, no vegetation effects, no seafloor weathering, etc.).

The study provides evidence that the dominant control on Earth’s silicate-weathering thermostat may have shifted during the Phanerozoic, with temperature control dominant for most of the interval examined but hydrology control temporarily dominant during the Pangea era.

Journal: Nature Communications

DOI: 10.1038/s41467-026-77289-3

Provided: University of Chicago

Authors: R. J. Graham,
B. B. Cael,
M. Fu &
D. S. Abbot

Abstract

Earth’s climate has remained habitable for billions of years, a stability usually attributed to a negative feedback from silicate weathering – the chemical breakdown of silicate rocks on land, which consumes atmospheric carbon dioxide faster as climate warms. However, whether temperature or hydrology primarily drives this feedback remains uncertain. Here we show the two controls leave geographic fingerprints: in an ensemble of climate simulations with randomized continents, temperature-controlled weathering depends on tropical land fraction, whereas hydrology-controlled weathering depends on continental fragmentation. Stronger weathering removes more carbon dioxide, cooling the planet, so each regime predicts anti-correlation between temperature and its controlling geography. Reconstructed global temperatures spanning 480 million years are anti-correlated with tropical land fraction, except from roughly 295 to 200 million years ago – overlapping the supercontinent Pangea – when they anti-correlate with continental fragmentation. The mechanism stabilizing Earth’s climate may thus have evolved, with temperature control apparently dominant for most of this period.

On El Hierro Island, At Least They Kept The Diesel Backup

On El Hierro Island in Spain, they set out to build an electricity system powered only by wind, with backup from a pumped-storage hydroelectric plant. The relevant statistics for El Hierro are: average electricity demand: 5 MW; nameplate capacity of the wind turbines: 11.5 MW (i.e., 2.3x “overbuild” compared to average usage); storage capacity of the pumped storage system: 70 MWh (i.e., 14 hours of average usage).

A panoramic view of El Hierro Island, showcasing wind turbines on a mountainous landscape with a coastal view. A power facility is visible in the foreground, with a pool of water and a pipeline leading to the structure.
AI generated by Meta

From The Manhattan Contrarian

By Francis Menton

On El Hierro Island in Spain, they set out to build an electricity system powered only by wind, with backup from a pumped-storage hydroelectric plant. The relevant statistics for El Hierro are: average electricity demand: 5 MW; nameplate capacity of the wind turbines: 11.5 MW (i.e., 2.3x “overbuild” compared to average usage); storage capacity of the pumped storage system: 70 MWh (i.e., 14 hours of average usage). The operator of the facility has provided eight years of operating data for the system. I reported on the results in my last post on October 23. In summary, the wind/storage system provided 56% of the island’s electricity use in the best year, and only 35% in the worst year.

During these years, the remainder of the island’s electricity — ranging from 44% in the “best” year for the wind system to 65% in the worst year — has been provided by a diesel generator. The wind/storage system has fallen far short of its stated goal of supplying all the electricity for the island. But at least they have kept the diesel generator around. The diesel generator has sufficient capacity to meet the full electricity demand of the island, even when the wind is calm and the storage reservoir is empty. As a result, the system operators have been able to continue to provide electricity to the residents despite the total failure of the wind/storage system to meet its promises.

But here’s some important information you may not be aware of. Here in the U.S., during the Obama and Biden administrations, the regulators took the opposite approach. Rather than proceeding like El Hierro, and building out a wind/storage (or a wind/solar/storage) system first, and only then reducing fossil-fuel backup capacity as that became feasible, they instead ordered that the fossil-fuel capacity must be shut on a fixed schedule without any knowledge or assurance that there would be sufficient wind, solar, storage, or anything else to replace it.

And this was for the whole country, not just for a small island of 11,000 people. All 340+ million Americans were to be enlisted as involuntary guinea pigs in this wild adventure.

Nor is this ancient history. After the Supreme Court’s 2022 West Virginia v. EPA decision struck down a prior Obama administration effort to force the closure of fossil fuel power plants, the Biden administration came back with a new version in April 2024. This Biden EPA Rule was finalized on April 24, 2024 with the incredibly verbose title “New Source Performance Standards for Greenhouse Gas Emissions from New, Modified, and Reconstructed Fossil Fuel-Fired Electric Generating Units; Emission Guidelines for Greenhouse Gas Emissions from Existing Fossil Fuel-Fired Electric Generating Units; and Repeal of the Affordable Clean Energy Rule.” I covered the issuance of this Rule in a post on May 1, 2024 titled “The Biden Administration Ever More Delusional On Energy.”

A commenter on that post suggested that because the title of the Rule was so long I should shorten it into an acronym using just the initials, NSPSFGGEFNMARFFFEGUEGFGGFEFFFEGUAROTACER.

From the Executive Summary of the NSPSFGGEFN. . . (you can fill in the rest):

In 2009, the EPA concluded that GHG emissions endanger our nation’s public health and welfare. Since that time, the evidence of the harms posed by GHG emissions has only grown, and Americans experience the destructive and worsening effects of climate change every day. Fossil fuel-fired EGUs are the nation’s largest stationary source of GHG emissions, representing 25 percent of the United States’ total GHG emissions in 2021. At the same time, a range of cost-effective technologies and approaches to reduce GHG emissions from these sources is available to the power sector—including carbon capture and sequestration/storage (CCS), co-firing with less GHG-intensive fuels, and more efficient generation. Congress has also acted to provide funding and other incentives to encourage the deployment of various technologies, including CCS, to achieve reductions in GHG emissions from the power sector.

The full Rule is over 1000 pages long, so it impossible to describe all its details in a short blog post. But the gist of the Rule was to set standards for power plants for maximum emissions of “greenhouse gases” in units of pounds of CO2 per MWh of energy output. The standards were such that over time no fossil fuel power plant could comply, except perhaps if it could somehow capture most of its CO2 emissions in a process called “Carbon Capture and Storage,” or CCS. You can see the Rule’s introduction there describing CCS as a “cost-effective technology.” But was it then? Or is it now?

The problem with CCS is that after many, many attempts there has never been a fully successful demonstration that it is cost-effective and functional at scale. Multiple well-informed commenters on the 2024 Rule provided detailed information on that subject, all of which the Biden EPA chose to ignore when it adopted the Rule. For example, here is a quote from the comment submitted by the Attorney General of Ohio in August 2023:

A study of 263 carbon-capture-and-sequestration projects undertaken between 1995 and 2018 found that the majority failed and 78% of the largest projects were cancelled or put on hold.  After the study was published in May 2021, the only other coal plant with a carbon-capture-and-sequestration attachment in the world, Petra Nova, shuttered after facing 367 outages in its three years of operation. . . . [T]his [SaskPower] facility is the world’s only [remaining] operating commercial carbon capture facility at a coal-fired power plant.   And it has never achieved its maximum capacity.  It also battled significant technical issues throughout 2021—to the point that the plant idled the equipment for weeks at a time.  As a result, the plant achieved less than 37% carbon capture that year despite having an official target of 90% . . . .

The SaskPower facility discussed in that comment is a small plant (115 MW) and has continued to face significant technical challenges since the time of the comment in 2023. Here is a report on that facility from December 2025 at something called the International CCS Knowledge Center. Excerpt:

The BD3 CCS Facility began operation in the fall of 2014 and, in its early days, focused on addressing design deficiencies. Many of the most valuable lessons came from unforeseen operational challenges that surfaced over time, which were addressed through hands-on experience. As the first facility of its kind to implement CCS technologies to significantly reduce emissions from a coal-fired power plant, it faced numerous engineering challenges that needed to be resolved to achieve the operational success it enjoys today.

The report is all about the “design deficiencies” and alleged “solutions” that have supposedly been implemented in the 13 years of operation. Missing from the report is any information on the wholesale cost of power from the facility, and how that might compare to the cost of wholesale power from the plant if they just disconnected the CCS part and let it run that way.

Meanwhile, I asked Google Gemini if any new CCS facilities at large power plants have gone into operation in the three years (2024-2026) since the comments on the Biden-era Rule were submitted. The answer:

No large-scale carbon capture and storage (CCS) systems attached to major fossil-fuel power plants have gone into commercial operation and successfully started up between 2024 and 2026.

I invite any reader to come up with an example of such a facility that has started up and operated successfully. From my research, I don’t think that it exists.

In the absence of a commercially reasonable CCS technology that can be attached to essentially all fossil fuel power plants, the Biden era NSPSFGG. . . Rule functionally amounted to an order to shut down the existing mostly-fossil-fuel based electricity system in this country, without any proven system capable of replacing it in the time period required. We would put up huge numbers of wind and solar generators (with massive taxpayer subsidies to support them), and no idea whether the system would work when the fossil fuel plants shut down. If that didn’t work, we could all just freeze.

Actually, as time goes on it is becoming more and more clear what the limits are for intermittent wind and solar electricity generation for powering a big electrical grid. Germany is the poster child for the wind/solar buildout. Germany’s total consumption of electricity for 2023 (latest year I can find) was 476 TWh, which would make its average usage about 54 GW. According to Germany’s Federal Network Agency, the country’s nameplate capacity of wind and solar generation facilities as of early 2026 was 210 GW. That’s an “overbuild” of almost 4x. Meanwhile, Germany has almost zero meaningful amount of energy storage to back up the wind and solar generation and compensate for intermittency. And the percent of electricity consumption from wind and solar that Germany was able to achieve in 2025 with that 4x capacity overbuild was (drumroll!!!!!) about 44%, according to a Report from Yale Environment 360.

You can buy more and more of these things, but they just produce more and more electricity that you don’t need (and must discard) on a breezy summer day, and nothing on a cold winter night when you need it the most. This is not really very complicated. When are they finally going to figure it out?

The North Sea Green Paradox

One of the most curious responses to the ongoing controversy around North Sea oil and gas is that permission for developments should not be granted because the wells are drying up.

After a great deal of delay, the Jackdaw field has finally been given consent by the Government, though the Rosebank field looks set to be denied. This has increased the volume of chatter from green quarters, the angry flurrying of which further exposes its departure from reality.

Oil rig platform silhouetted against a colorful sunset over the ocean.
AI generated

From The Daily Sceptic

By Ben Pile

One of the most curious responses to the ongoing controversy around North Sea oil and gas is that permission for developments should not be granted because the wells are drying up. I’ve long argued that the authors of green arguments owe little to their maths teachers, but any sense of logic or proportion is often conspicuously absent. After a great deal of delay, the Jackdaw field has finally been given consent by the Government, though the Rosebank field looks set to be denied. This has increased the volume of chatter from green quarters, the angry flurrying of which further exposes its departure from reality.

Ahead of the Government’s Jackdaw decision, it was the Guardian that claimed that “Heat pumps and insulation would cut UK living costs more than new oilfields, study suggests.” The ‘study’, however, seemed to be merely a blog post published on the website of the influential green think tank E3G a week earlier. Rather than presenting any new research, the post collected some anti-North Sea development talking points, most of which were themselves scraped from other green blob-funded fake civil society organisations.

“North Sea revenues are declining dramatically,” claims E3G. In support of this claim, it produces the following alarming chart, which does indeed look volatile. It shows a precipitous decline in revenues at the start of the preceding decade, spiking again during the post-lockdown era, followed by a projection back to zero. “New licences cannot restore these revenues,” it asserts.

Graph showing the historical volatility of North Sea oil and gas revenues in the UK, with projected declines from 2025 to 2031. Key points include a net loss in 2016-17 and projected revenue collapse within five years.

But E3G’s chart is misleading. Yes, revenues are volatile. But the causes of this volatility and its tendency towards zero are not direct representations of geological reality. This is shown by a chart of the same data on an axis that spans the history of North Sea oil and gas.

Line graph depicting oil prices and UK revenue from 1970 to 2024, showing trends in revenue in millions (£), WTI and Brent crude prices, with distinct color lines representing each data series.

In 1984, the Treasury made £40 billion from North Sea oil and gas revenues in today’s money. These revenues diminished into the 1990s to levels we have today, before increasing through the 2000s, into the precipitous decline seen in the 2010s. So E3G’s argument is falsified by data of which it shows only a small window.

But what caused that volatility? There is obvious correspondence between oil prices and revenues. Revenue tracks oil prices through the 1980s and 2000s. Yet high prices did not produce big revenues in the 2010s. Another part of this story is the tax policy context. The Institute for Fiscal Studies (IFS) provides the data.

Line graph showing tax rates on North Sea profits from 1973 to 2030, with different lines representing oil and gas fields approved before and after 1993. Highlights include tax rate changes before and after an Autumn Statement, including projected additional revenue.

The IFS’s chart is slightly outdated – the Labour Government increased and extended the ‘Autumn Statement’ oil and gas tax regime, such that the figure is now 78%. But that’s not important to understanding the historical picture. It also puts the current regime in context: the North Sea has often been subject to quite punitive taxes – above 80% for nearly the entire 1980s. Wells developed after 1993 were taxed at increasing rates – from 30% in the early 2000s to over 60% by the early 2010s – mostly under the Labour government but topped off by Chancellor George Osborne in 2011.

High tax rates didn’t dissuade record levels of investment, driven by rising energy prices. According to a 2017 UK government analysis, between 2010 and 2014, capital expenditure nearly doubled. But very little of this went on exploration and appraisal; most went on developing existing assets. A 2015 analysis by Professor Alexander Kemp at the University of Aberdeen for the Scottish Government suggested that the 2011 tax rises “by reducing full cycle returns to investors could also have played a role in curtailing exploration and appraisal”. The subsequent collapse in energy prices then undermined business plans, and turned revenue net negative for the years 2015 and 2016.

A bar chart illustrating upstream oil and gas expenditure in billion pounds from 2000 to 2017, displaying categories for decommissioning costs, operating costs, capital expenditure, and exploration & appraisal spend.

Rising costs and diminishing geological prospects may certainly have played their roles. But with little more than 5% of total expenditure going on exploration at peak prices, the image painted by green organisations of a desperate scrabbling around for the last drops of oil and gas is hardly supported. The viability of North Sea prospects is a much more complex story, and one that is as much affected by politics as by the state of the resources. And it is notable, moreover, that this episode coincided with the shale gas and oil controversy, in which green blob-funded organisations launched high-profile anti-fracking campaigns to sour the public mood against hydrocarbon resources of all kinds.

With fracking and conventional energy production, the green claim is a curious paradox. At the same time as they demand the prohibition of further licensing, they argue that the resources are exhausted, or not economically recoverable. But if they are not viable, then why the panic about their exploitation bringing about ‘Thermogeddon’? They can’t claim that they’re concerned for the poor investors behind Jackdaw and Rosebank, who might lose their shirts.

The paradox doesn’t stop there. “Tax revenues from the North Sea were about £4 billion in 2025–26, but upstream tax relief and support measures amounted to an estimated £3.26 billion,” claims the Guardian. The issue upsetting the newspaper and the green lobbying outfit is that firms are able to write off costs for decommissioning, such as capping well heads. As decommissioning costs rise, the taxpayer may be left as the underwriter if energy companies find themselves underwater at the end of their projects’ lifecycles.

Decommissioning costs are rising. According to Offshore Energies UK, “Decommissioning accounted for 15% of total oil and gas expenditure in the [North Sea] in 2024 and is expected to rise beyond 30% by the end of the decade,” and “decommissioning spend could potentially overtake capital expenditure as early as 2028”. But caution, again, is needed before rushing to the conclusion that this is owed to inherent issues with oil and gas production or with geology.

For a start, all forms of construction (of which decommissioning is a subset) are increasing in cost. This has become a fetter on all forms of development, green or otherwise, and this drag on growth has become the focus of a new wave of civil society organisations (or think tanks), some of which are green blob-funded, but which invariably pin the blame on regulation.

Perhaps the most notorious example of cost explosion has been the Botley Road railway bridge at the edge of Oxford’s city centre. With an initial cost estimate of an already eye-watering £161 million, construction began in 2023 but hit problems. It was completed last month amid global controversy. “Why does it cost £237 million to build a railway bridge?” asked Sam Dumitriu, Head of Policy at Britain Remade, in the Spectator.

But Dumitriu’s question might be better asked of Britain Remade’s major funder, the European Climate Foundation (ECF). ECF and its parent organisation, the Climateworks Foundation, take credit for, among many other things, leading the development of the European Union’s 2050 roadmap – an agenda that was all but explicit in its ambition for the deindustrialisation of the entire continent, including Britain. That agenda required the dismantling of coal-fired power stations, and it required the dismantling of oil and gas production, not merely emissions-reduction.

Deindustrialisation costs, and in turn increases the costs of everything that industrial society depends on, including bog-standard railway bridges. And that takes us to the second point. The decline of the North Sea is a policy decision. It was signalled extremely clearly by the incoming Labour Government that no more licences were to be issued. And that included the fields that had been explored, but had not yet been fully developed. Most notably, this held up the Jackdaw and Rosebank fields, which were discovered in 2005 and 2004 respectively, and had not yet received full consent by the time of the change of government. That is to say that it was government policy to prevent the fruits of two decades of oil and gas exploration coming onstream. Moreover, those two decades have been years in which governments of all parties have made clear their intention to ultimately destroy the hydrocarbon sector. And that is almost certainly reflected in the economic data pertaining to North Sea capital expenditure, including the relative proportions of exploration of new fields vs expanding existing concerns, and vs decommissioning costs.

But perhaps simple greed motivates this irrational environmentalism. The Guardian offers no evidence but claims that “The Government’s £15 billion warm homes plan […] would slash £1 billion a year from household energy bills across the UK” and “would draw in a further £15 billion in private investment”. But private investment in the North Sea – and indeed in fracking – would easily rival that annually, and would moreover create the possibility of returning prices to their 2003 lows – and lowering domestic energy prices accordingly, by far more than taxpayer-funded subsidies. Even if it were free money, £30 billion would buy only something like two million heat pumps – a far cry from the 28 million homes and countless commercial and public buildings that need heating too. Deindustrialisation costs, and there’s a lot of money needed to meet green policy objectives.

If green policy, advanced on bullshit spun by fake charities like E3G and pumped into the public sphere by the Guardian, forces homes into spending £tens of thousands each, then £trillions of finance will be required from financial institutions. It can only be a coincidence, then, that the funders of the green blob, including the ECF’s and the Guardian’s ‘philanthropic’ grantors, are typically hedge funds and their proprietors with interests in ‘low carbon finance’ and suchlike. And if it wasn’t merely a coincidence – which it certainly was – that would make the green movement in toto nothing more than an extremely cost-effective financial services marketing and lobbying operation.

New Open Database Unifies 24 Years of Satellite Data to Track Earth’s Water Cycle

WISO- SAT is a new open- access database that standardizes and harmonizes ~24 years (2002- 2024) of satellite measurements of stable hydrogen isotopes (mainly δD, the deuterium- to- hydrogen ratio) in atmospheric water vapor from eight missions.

Water isotopes act as natural tracers or “fingerprint”. Their ratios reveal where water vapor originated and the processes (evaporation, condensation, transport) it experienced.

A global overview of the water cycle illustrating 24 years of satellite measurements, featuring satellite icons for NASA missions including AQ, GPM, SMAP, GRACE-FO, ICESat-2, and ESA's SMOS, along with data streams showing evaporation, precipitation, water vapor transport, and cloud formation.
AI generated by Grok

WISO- SAT is a new open- access database that standardizes and harmonizes ~24 years (2002- 2024) of satellite measurements of stable hydrogen isotopes (mainly δD, the deuterium- to- hydrogen ratio) in atmospheric water vapor from eight missions.

It was developed by an international team led by Rice University researcher Mampi Sarkar (corresponding author), with Sylvia Dee (associate professor of Earth, environmental and planetary sciences at Rice) and collaborators from NASA/JPL, European institutions, Japan, and others.

The work is described in a paper published in Scientific Data (Nature). The Rice University news release covering it was written by media relations specialist Rachel Leeson (dated Oct. 26, 2026).

Water isotopes act as natural tracers or “fingerprint”. Their ratios reveal where water vapor originated and the processes (evaporation, condensation, transport) it experienced.

Satellites have measured these for decades, but each mission (SCIAMACHY, GOSAT, GOSAT- 2, TROPOMI, TES, AIRS, CrIS, IASI) used different instruments, formats, calibrations, grids, altitudes, and sampling strategies.

Combining datasets previously required up to a year of labor- intensive cleaning and reconciliation, and efforts were often duplicated worldwide.

WISO- SAT solves this by collecting the raw data, applying bias corrections across platforms, quantifying uncertainty, and distributing instrument-specific gridded NetCDF products at 1° × 1° and 5° × 5° resolutions (monthly δD and moisture concentration). The standardization pipeline itself is public, so new data can be added in a consistent way.

Researchers can now more readily study:

  • Moisture transport, cloud formation, precipitation, and atmospheric rivers
  • Decadal climate variability and seasonal- cycle changes
  • El Niño and La Niña influences
  • Land- atmosphere interactions (e.g., deforestation, soil moisture, evapotranspiration)
  • Evaluation and improvement of isotope- enabled climate models (GCMs)

Satellites provide coverage of remote regions (oceans, poles) that ground instruments cannot easily reach and offer consistent long-term records.

The project was supported by the U.S. National Science Foundation and NASA.

The public database and processing code lower barriers for the broader scientific community, students, and others studying Earth’s water cycle.

_______________________________________________

WISO-SAT: A global database of stable hydrogen isotopes in water vapor from eight satellite missions

Overview

This is an open- access Data Descriptor paper introducing WISO- SAT, a harmonized multi- instrument database of monthly δD (deuterium excess and stable hydrogen isotope ratio, HDO/H₂O) and moisture concentration retrievals in atmospheric water vapor.

It compiles and standardizes data from eight satellite missions spanning 2002–2024:

  • SCIAMACHY
  • GOSAT
  • GOSAT-2
  • TROPOMI
  • TES
  • AIRS
  • CrIS
  • IASI

Key features

  • Products: Instrument- specific gridded NetCDF files at 1° × 1° and 5° × 5° horizontal resolutions.
  • Standardization innovations: Cross- platform bias correction and uncertainty quantification to enable intercomparison despite differences in time periods, altitudes, formats, and instrument characteristics.
  • Open resources: Public repository with the NetCDF files and preprocessing and standardization codes. Example notebooks and scripts are included for model–satellite averaging-kernel application and regression- based bias correction (e.g., for surface δD comparisons).

Scientific motivation and applications

Stable hydrogen isotopes (especially δD) serve as tracers of the hydrological cycle and climate dynamics. Prior satellite records were fragmented, making multi- mission analysis labor- intensive. WISO- SAT fills observational gaps (especially remote regions) and supports:

  • Studies of decadal climate variability and seasonal- cycle changes
  • Process- level research on moisture transport, rain formation and evaporation, atmospheric rivers, etc.
  • Evaluation and development of isotope-enabled general circulation models (GCMs)
  • Broader atmospheric science and hydrology applications

Authors and funding

Corresponding author: Mampi Sarkar (Rice University).

Key co- authors include Sylvia Dee and Michelle Frazer (Rice University), plus collaborators from the University of Michigan, Oregon State University, SRON (Netherlands), University of Bremen, Karlsruhe Institute of Technology, NASA GISS, Jet Propulsion Laboratory (California Institute of Technology), and University of Bergen.⁠

Funding includes U.S. National Science Foundation awards (CAREER 2338861, SCI- SWIM 2513024) and NASA support (including the NEWS SPICE project and JPL contract).

Access

  • Article page: https://www.nature.com/articles/s41597-026-08218-8 (Open Access under CC BY-NC-ND 4.0).
  • PDF download link is available on the page.
  • Supplementary information PDF is also provided.
  • The actual data repository (NetCDFs and code) is referenced in the paper as open-access.

This is the primary scientific publication behind the recent Rice University press coverage on the open water-isotope database.

Journal: Scientific Data (Nature)

DOI: 10.1038/s41597-026-08218-8

Published: 8 September 2026 (early access / accepted version)

Provided: Rice University

Authors: Mampi Sarkar,
Sylvia Dee,
Michelle Frazer,
Adriana Bailey,
Stephen Good,
Soumyajit Mandal,
Stefan Noël,
Matthias Schneider,
Hayoung Bong,
Kevin Bowman,
Hans Christian Steen-Larsen,
Marja Haagsma &
John Worden

Abstract

Stable isotopes of hydrogen, including deuterium (δD), provide a critical tracer for understanding Earth’s hydrological cycle and climate dynamics. Recognizing this, the last two decades have seen a number of remote sensing missions geared towards measuring the ratio of HDO/H2O in water vapor. At present, however, observational gaps persist in remote regions and across satellite platforms. Furthermore, these data span different time periods, altitudes, and are inconsistently formatted, complicating intercomparison. To address this, we describe WISO-SAT, a harmonized multi-instrument database of monthly δ D and moisture concentration retrievals from eight satellite missions (SCIAMACHY, GOSAT, GOSAT-2, TROPOMI, TES, AIRS, CrIS, IASI) distributed as instrument-specific gridded NetCDF products at 1° × 1° and 5° × 5° horizontal resolutions. Key innovations and standardization of these 8 data products are made through bias correction across platforms and by providing uncertainty quantification. The dataset spans 2002–2024, enabling studies of decadal climate variability and changes in the seasonal cycle. These standardized and publicly available water vapor isotope products address a critical gap in isotopic observations from satellites across different timelines, supports climate model evaluation and development (e.g., isotope-enabled GCMs), and process-level studies of atmospheric phenomena such as moisture transport, rain formation and evaporation, and atmospheric rivers. An open-access repository includes NetCDF files and preprocessing codes used to format each dataset. We also provide example notebooks and scripts demonstrating model-satellite averaging kernel application and regression-based bias correction for surface δ D comparison. WISO-SAT enables novel applications in atmospheric science and hydrology, and provides an open data product that can be used to validate the simulation of Earth’s water cycle in GCMs.