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Earth's subsurface may hold up to 5.6 × 10⁶ million metric tons of hydrogen
- pfdietz 2y agoIf extracted and fully oxidized, the water would raise ocean levels maybe 4 cm. The Earth also includes vast quantities of reduced metals like iron, more than enough to react with all the oxygen in the atmosphere. Perhaps some way could be found to exploit that, at least a little bit.
- foundart 2y agoWell there's an idea for a sci-fi disaster book: "Rustpocalypse" (if too much of that iron were to be oxidized.)
- suprfsat 2y agoRust Evangelion Strike Force
- FredPret 2y agoApocalypse (written in Rust)
- seangrogg 2y ago*rewritten in Rust
- pfdietz 2y agoAll it would take would be for photosynthesis to be terminated, and then wait a few million years for erosion and volcanism to expose enough reduced material to soak up the atmosphere's oxygen. What's weird is that, as far as I know, there's no feedback mechanism that's been identified that keeps the atmosphere's O2 level stable. It may have been stable since the Cambrian just because if it hadn't been, we wouldn't have evolved, an anthropic argument.
- Earw0rm 2y agoFire must surely have a role to play there? Too much O2 and plants burn easily, too little and fires won't take hold. And we don't know AFAIK that it's been entirely stable. There's some debate over what the level was in the Cretaceous for example.
- pfdietz 2y agoIf anything, fire would be a positive feedback. That's because fire produces charcoal, and charcoal doesn't decompose. Instead, it gets washed into the ocean and eventually buried. It's not photosynthesis itself that causes O2 accumulation in the atmosphere, it's the burial and sequestration of reduced material from photosynthesis.
- ryao 2y agoIf the metal is reduced, then it should not be reactive. How does this become relevant to all of the oxygen in the atmosphere?
- pfdietz 2y agoWhat? Carbon is reduced. Hydrogen is reduced. Any fossil fuel is reduced. All can give up electrons to oxygen and so be oxidized, liberating energy.
- ryao 2y agoI went with what you wrote since it has been a while since I took general chemistry, but upon doing a simple lookup, I found that your terminology is wrong. In redox reactions, the oxidizing agent is reduced while the reducing agent is oxidized: https://en.wikipedia.org/wiki/Redox https://en.wikipedia.org/wiki/Redox Here, the metal is the reducing agent. If it were somehow reduced in redox reactions, there not much chance of it being oxidized as that would make the metal an oxidizing agent that wants electrons, not a reducing agent that gives electrons. That said, these things have already been oxidized (not reduced) and thus there is no chance to have them consume oxygen. You need the pre-oxidized material in order to be able to consume oxygen. Finally, you failed to answer my question regarding the relevance of these metals to atmospheric oxygen. They should be inert having been oxidized long ago. That is why rocks are full of oxides, such as silicon dioxide and aluminum oxide, despite being composed of metal.
- pfdietz 2y agoI think there's confusion here between "is reduced" meaning "has been reduced" vs. "and is then reduced". Iron in the Earth is mostly in a reduced state (either Fe(+2) or even elemental iron). Upon exposure to the atmosphere it is oxidized to Fe(+3), changing from a more reduced to a more oxidized state (and similarly for other things in reduced states, such as manganese and sulfur and organics).
- ryao 2y ago
- tolciho 2y agoBanded Iron Formation: the reunion tour.
- blindriver 2y agoIf the hydrogen gas escaped and left the atmosphere, would it affect the orbit around the sun, possibly causing the Earth to cool too much?
- deleted 2y ago[deleted]
- tzs 2y agoI'd expect not, for 2 reasons. • I can't think offhand of any mechanism by which it would escape in some preferred direction. I'd expect to be pretty much evenly spread in all directions, so any effects on the orbit of what remains caused by the hydrogen leaving in any particular direction would be cancelled out by the effects of hydrogen leaving in the opposite direction. • We are talking about 5.6 x 10^12 tons of hydrogen. The mass of the Earth is 5.972 x 10^21 tons. The mass of the hydrogen is about 1 billionth the mass of Earth. That's about the ratio of the mass of a grain of rice to the mass of the International Space Station. Tossing that small of mass away, even if it was all in one direction, is not going to do anything significant to your orbit unless you tossed it away with very very very high velocity. A naive calculation just using Newtonian mechanics suggests it would have to be much faster than the speed of light to carry enough momentum away to matter. I'll leave it to others to figure out what fraction of the speed of light it would have to be going to have equivalent momentum.
- Someone 2y ago> I can't think offhand of any mechanism by which it would escape in some preferred direction. I think the sun’s heat would give it a slight preference to escape from the sunny side of earth.
- hollerith 2y agoNo because the escaping gas would on average have the same velocity as the (lighter) Earth does.
- ngcc_hk 2y agoIf two mass separated, it will affect their velocity. But does this hydrogen escapee like a rocket gas. Or it is just a restructure or a bit move of CoG. One also note if it not too fast escape as earth rotate the overall effect depend upon the uniformity of the “escape” as the net effect can be zero or more depends upon its location on earth. Mostly as it is not align with the tangent of travel, it will affect. How much as point out relates also the mass. But even the minor variations make the polar star changes. It will have affect.
- sebastianmestre 2y agoThe figure in the title expressed in normal units 5.6 * 10^15 kilograms
- WorkerBee28474 2y agoI think you meant to say 1.1 trillion elephants
- acchow 2y ago2.24 billion olympic sized swimming pools
- adonovan 2y agoThanks, I didn’t notice the second million and wondered why a day’s supply of energy would be scientific news.
- peeters 2y agoThey wasted an opportunity to get a third thing meaning "million" into the same number with 5.6 x 10^6 million megagrams.
- ars 2y agoThere is around 1 trillion tons of oxygen in the atmosphere, if you burned all the hydrogen you would deplete all of the oxygen on earth. Let's not. Although realistically we only need a tiny fraction of the hydrogen.
- stouset 2y agoOn the plus side if we use up all the oxygen, we’ll have solved the problem of burning fossil fuels producing CO2!
- shiroiushi 2y agoIf we use up all the oxygen, we'll have solved every social or political problem that currently plagues humanity. I think it's a good strategy.
- dmichulke 2y agoFWIW, I consider extinction avoidance also a political problem
- selimthegrim 2y agoThis is like the Bojack Horseman prescription to solve America’s gun problem (Watch the show, I won’t spoil it)
- hgomersall 2y agoCloser to 10^15 tonnes, so a few orders of magnitude out.
- shwouchk 2y agoIf siblings are to be believed, there is nothing we can do about it aside from being very careful not to release the hydrogen into the atmosphere (at which point it will “burn” whether we want to or not)
- m3047 2y agoPurple Earth hypothesis. The first (AFAWK) photosynthetic critters were cyanobacteria. They produced enough oxygen to kill off everything which couldn't withstand its reductive effects. Oxygen levels have been much higher than they are today, presumably this is what made e.g. 6 foot centipedes a possibility.
- fulafel 2y agoThis article the crux, is this about extractable hydrogen or some proxy about it (vs just "interesting number"), to the last sentence. The abstract is again the best summary: "[...] Given the associated uncertainty, stochastic model results predict a wide range of values for the potential in-place hydrogen resource [103 to 1010 million metric tons (Mt)] with the most probable value of ~5.6 × 106 Mt. Although most of this hydrogen is likely to be impractical to recover, a small fraction (e.g., 1 × 105 Mt) would supply the projected hydrogen needed to reach net-zero carbon emissions for ~200 years."
- Animats 2y agoThe Albanian mine: "The researchers found that the gas bubbling from the pool was more than 80 per cent hydrogen, with methane and a small amount of nitrogen mixed in. It was flowing at a rate of 11 tonnes per year, almost an order of magnitude greater than any other flows of hydrogen gas measured from single-point sources elsewhere on Earth’s surface. To determine the source of the gas, the researchers also modelled different geological scenarios that could produce such a flow. They found the most likely scenario was that the gas was coming from a deeper reservoir of hydrogen accumulated in a fault beneath the mine. Based on the geometry of the fault, they estimate this reservoir contains at least 5000 to 50,000 tonnes of hydrogen. “It’s one of the largest volumes of natural hydrogen that has ever been measured,” says Eric Gaucher, an independent geochemist focused on natural hydrogen. But it still isn’t a huge amount, says Geoffrey Ellis at the US Geological Survey." This is the second or third time someone found modest amounts of hydrogen underground, and then started making claims of vast quantities being available. There's been so much well-drilling worldwide for other materials that if hydrogen was anywhere near the surface, it would have been found by now. The "gold hydrogen" enthusiasts claim well depths of a few kilometers are enough. Oil and natural gas wells routinely go that deep. So far, nobody has a "natural hydrogen" well producing. Even though this startup [1] said they would have one by the end of 2024. Their "news" releases are all about going to meetings, making deals, and such. Not much mention of drilling, unlike the statements they made a few years ago. There's one well in Mali which yields enough hydrogen to run an auto engine driving a generator. That's it for actual output. That deposit been known since the late 1980s, and invested in since 2012. Exploratory wells were drilled in 2018. Results from that are, somehow, hazy.[2] Not finding followups since 2018. The hype is strong here.[3] [1] https://helios-aragon.com/news/ https://helios-aragon.com/news/ [2] https://www.sciencedirect.com/science/article/abs/pii/S0360319918327861 https://www.sciencedirect.com/science/article/abs/pii/S03603... [3] https://www.scopus.com/record/display.uri?eid=2-s2.0-85186957751 https://www.scopus.com/record/display.uri?eid=2-s2.0-8518695...
- roenxi 2y ago> There's been so much well-drilling worldwide for other materials that if hydrogen was anywhere near the surface, it would have been found by now. I'd believe it because geologists are thorough. I'd also not be that shocked if nobody was testing for hydrogen because it is a gas. I'd imagine it is possible to drill through a hydrogen deposit and not even notice it is there. Are we sure that the prospectors were checking for hydrogen? All over the globe? I suppose if they found a real lode of the stuff it might accidentally blow up the drilling crew. That'd make headlines.
- oefrha 2y ago> stochastic model results predict a wide range of values for the potential in-place hydrogen resource [10^3 to 10^10 million metric tons (Mt)] with the most probable value of ~5.6 × 10^6 Mt. As a former physicist, I find it hard to take anyone who dares to give two significant figures on such a terrible estimate seriously. At the very least tells me they don’t know shit about statistics. And whoever is clueless enough to repeat the figure in such a misleading title should be banned from scientific publishing.
- phtrivier 2y agoWhen I started doing math seriously, I also feel strongly in love with "existence proof", where you were asked to prove that "something" existed, and any logical reasoning was considered fair game, even if you never found the "something". Then, I started doing applied maths, where proving the existence of a solution is a nice bonus, but finding an approximate solution is the goal. Here, we have an example of a funny proof of existence that does not tell you where to drill. Some carbon was emitted during the publishing of this model - that will be so much more carbon to offset if we ever end up actually finding some real hydrogen.
- h_tbob 2y agoCO2 has its problems but at least nature automatically recycles it and produces O2 again. But what about hydrogen? Wouldn’t burning it consume our oxygen supply with no way to replenish without large scale electrolysis? Seems like this could be a worse disaster since nature doesn’t do that by default.
- dvh 2y agoIt's only 0.000001 of the mass of Earth's atmosphere (assuming 5e18kg)
- philipkglass 2y agoNo, photosynthesis turns water into oxygen and hydrogen-containing organic compounds. https://en.wikipedia.org/wiki/Photosynthesis#Refinements https://en.wikipedia.org/wiki/Photosynthesis#Refinements Samuel Ruben and Martin Kamen used radioactive isotopes to determine that the oxygen liberated in photosynthesis came from the water.
- johnea 2y agoAlright! More stuff to set on fire!!!
- Eddy_Viscosity2 2y agoIS this alot alot? Like how much hydrogen would be needed to capture all of the atmospheric oxygen and how much water would that make?