
In theory, rocks from Oman could store hundreds of years of human CO2 emissions - subliminalpanda
https://www.nytimes.com/interactive/2018/04/26/climate/oman-rocks.html
======
DrPhish
The best long-term carbon sequestration medium we have is wood.

It is the slow and unsexy algorithm of:

Plant trees, and then build things with them. Be careful not to burn them.
Repeat

~~~
lbenes
Your theory sounds good until you consider the practical aspects of the last
step:

> Be careful not to burn them. Repeat

So what do you do with the wood? A billion years ago, your plan would have
worked out brilliantly. Some say it's where our oil came from. But now we have
fungus among us that evolved to rapidly turn your wood right back into CO2.

Unless you sterilize the wood and bury it deep in the ground where it will
never be exposed to air or spores, you're right back to square one. Also
there's the logistics and carbon footprint of burying and sterilizing the
wood.

You're not the first person to think of this:

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266747/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266747/)

~~~
mrfusion
Could we mass pressure treat wood to prevent it from being eaten?

~~~
lettergram
That only works for a period of time depending on conditions. In this case,
even a few hundred years wouldn't be good enough.

~~~
lbenes
Hundred? If the wood is touching soil, try a few decades at best. I just
replaced an old rotted out deck that was all pressure treated lumber. Also EPA
considers it a hazardous waste.

[https://www.epa.gov/ingredients-used-pesticide-
products/chro...](https://www.epa.gov/ingredients-used-pesticide-
products/chromated-arsenicals-cca)

------
opportune
How dangerous is it to breathe in particulate matter from peridotite? There's
another approach to making sequestration within these rocks economical - we
could use underground explosives to simultaneously disperse peridotite
particles into the air and uncover formations that haven't been exposed to CO2
yet. This would drastically increase the surface area and hence absorptive
power of the rocks.

Even if this could be done in a manner that keeps the air safe to continue
breathing, the other problem from doing too much of this is that it could
increase the Earth's albedo and have a global cooling effect (akin to when
volcanic eruptions on earth have caused famines, skipped summers/growing
seasons). But in some ways, that may make this the perfect worst-case-scenario
solution to runaway global warming. We could periodically use "clean" nuclear
detonations to put enough particulates in the air to reduce the global
temperature _and_ sequester carbon. Once the particulates settle, if there is
still too much CO2, we could do another round of detonations, etc.

~~~
legostormtroopr
This is how apocalypse movies start.

~~~
opportune
Well, I'm sure in a limited case it wouldn't be that dangerous. But yeah,
regarding the nuclear detonations, that's why I think it would have to be a
last resort. Like, last resort as in a situation where humanity is in danger
of extinction or in making Earth mostly uninhabitable.

~~~
dflock
So, now then.

~~~
zeth___
More like 30 years ago.

But yes, now would be good too.

~~~
matte_black
In that case we should adopt a more cavalier attitude toward nuclear weapons.
If we allow at least one nuclear exchange between two nations we could help
offset the effects of global warming for a good while longer.

~~~
zeth___
Ocean acidification isn't helped by nuclear weapons.

------
tim333
It seems to me there is much promise in influencing the natural carbon cycle
in these kind of ways. Apparently natural processes release and absorb about
800 gigatons of CO2 annually against human emissions of 29 gigatons or so, so
there seems a lot of scope to try to tip the natural balance a few percent.
Especially if we go carbon neutral and are then looking to reabsorb a bit.

[https://www.skepticalscience.com/human-co2-smaller-than-
natu...](https://www.skepticalscience.com/human-co2-smaller-than-natural-
emissions.htm)

~~~
coldtea
> _processes release and absorb about 800 gigatons of CO2 annually against
> human emissions of 29 gigatons or so_

We don't see to be growing more trees anytime soon, and we aren't adding any
new oceans either.

~~~
tim333
There's this kind of thing "Surge in plant growth explains slower CO2 rise
over past decade" [https://www.carbonbrief.org/surge-in-plant-growth-
explains-s...](https://www.carbonbrief.org/surge-in-plant-growth-explains-
slower-co2-rise-over-past-decade)

which has happened without really any planning. It's just that sort of stuff
could be actively encouraged.

------
anoncoward1234
I remember reading this article waiting for my haircut this morning.

Here was my biggest takeaway:

> More realistically, he said, Oman could store at least a billion tons of CO2
> annually. (Current yearly worldwide emissions are close to 40 billion tons.)

So we're looking at 2.5% sequestration of what we're _currently_ adding, from
the largest deposits in the world. Best case, realistically.

The whole thing sounds like a total non-starter.

~~~
simonh
Sometimes the way you solve a big complex distributed global problem is a bit
at a time. It’s unlikely we’re going to find one single global solution to
carbon sequestration.

~~~
coldtea
> _Sometimes the way you solve a big complex distributed global problem is a
> bit at a time._

An example of such a time, from various available such historical "sometimes"?

~~~
simonh
There are so many examples I don't even know where to start. Disease
eradication (through education, sanitation improvement, suppressing disease
vectors, vaccination, etc), then there's poverty reduction, the way piracy was
eradicated in the 19th Century, the way ozone depletion was tackled. There are
endless examples.

Anyway, what are you actually saying other than taking a cheap shot?

------
valw
Or, you know, maybe we could just emit less CO2 to start with.

To be clear, I'm all for research about carbon sequestration, but it should
not be an excuse to keep polluting irresponsibly. On the long term, we simply
can't get away with compensating all our big negative impacts with big
positive ones - how about introducing some moderation in our lifestyles
instead?

~~~
FreeFull
If we want to avert a bad scenario, we need to both drastically reduce CO2
emissions and find a way to sequester the CO2 currently in the air (either
through technological means, or through something like making big tracts of
land into forests). Just sequestering is unlikely to be enough, unless it is
extremely efficient.

------
DoctorOetker
"Fake" or rather misleading news!

So:

Geologists for a long time assumed the carbonates found with igneous rocks
resulted from CO2 reacting with these igneous rocks were formed very very long
ago.

A scientists uses carbon dating and discovers that the carbon in these
carbonates was in fact formed relatively recently.

This should prompt 2 questions, but seemingly only prompted the first:

1) If unreacted pyroxenes and olivine in these rocks can capture CO2 to form
carbonates relatively fast on geological timescales, can we help this natural
process speed up?

Answer: yes, but unclear at what energetic cost, and unclear what to do with
these carbonates afterwards.

2) WHERE do the carbonates end up, if the carbonates from older carbon are
mysteriously MISSING???

Answer: reacting back to CO2 upon rainfall, or by erosion and weather ended up
in seas and lakes!

One does not need rocks to create cabronates: simply expose water with CO2 and
CO2 will both absorb as (CO2)_gas and also react with water to form carbonic
acid H2CO3:

(H2O)l + (CO2)g <=> (H2CO3)l

If we take the resulting say magnesiumcarbonate from the rock that has
captured CO2, and put it in water, it will first dissociate like all salts
(metal, non-metal compounds) resulting in free mobile Magnesium ions and free
mobile carbonate ions. You might as well just let CO2 in the air react with
the sea acidifying it...

They pretend the carbonate form is a sink where we can dump our CO2, while in
fact this very interpretation is inconsistent with the original discovery that
the carbon in these carbonates is young. If it was truely stable the
carbonates would predominantly contain old carbon.

So unless they have a plan to store these carbonates and protect it from
rainfall, and prevent it from flowing into bigger bodies of water, I see no
solution, only excuses to appear green such that banks can invest "green
money" into these mining companies again, or perhaps to get "green subsidies"
or perhaps to escape carbon taxes...

------
lafar6502
Plants are pretty good at capturing carbon, why would anyone want something
more expensive and difficult?

~~~
pfdietz
The area of plants needed to capture current CO2 emissions would be impossibly
large. The energy efficiency of photosynthesis is horrible. In contrast,
mineral carbonation is an exothermic process, in principle requiring no energy
input.

------
mirimir
It's an intriguing idea. But you'd need to move humongous quantities of sone,
air and water. Without releasing so much CO2 to negate advantages.

~~~
cperciva
Which is why we need nuclear power.

~~~
mirimir
Perhaps so. With inherently safe designs, though.

Not some simplistic scale-up of Rickover's submarine engine.

~~~
coldtea
> _With inherently safe designs, though._

Funny how with reactors always the new designs are "safer" or "100% safe".
Until time passes, and those are the "old unsafe designs". It's like there's
an industry selling and promoting them each time (no, wait...)

------
mrfusion
Could we do this on Venus to start terraforming?

~~~
shasheene
[https://en.wikipedia.org/wiki/Terraforming_of_Venus#Capture_...](https://en.wikipedia.org/wiki/Terraforming_of_Venus#Capture_in_carbonates)

Sounds like it could more than halve the atmosphere (from 93 times Earth
atmosphere to 43 times).

Though worth remembering that the surface of Venus is an untouched wilderness
region containing billions of years of geologically significant information.
I'm all for walking around a balmy Venus, but if it involves pulverising the
surface, we need to be extracting all the scientific information from the
untouched wilderness area as we do it, because a lot will be lost forever
otherwise.

------
voidmain
Find a way to extract enough energy from this reaction (it has to be at least
slightly exothermic) to pay for it, and we're good.

------
ggm
I think Yogi Berra said it best:

 _In theory there is no difference between theory and practice - in practice
there is_

[https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Min...](https://en.wikipedia.org/wiki/Carbon_capture_and_storage#Mineral_storage)

~~~
dang
Not Yogi Berra, nor any of the other celebrities quotes end up sticking to,
but one Benjamin Brewster:

[https://quoteinvestigator.com/2018/04/14/theory/](https://quoteinvestigator.com/2018/04/14/theory/)

~~~
ggm
in _theory_ said by Yogi Berra.. but in _practice_ ...

------
spodek
It could store even more years' worth if we decrease our emissions.

I don't mean a general "we." I mean you, reading these words, and me. You can
decrease your emissions, plastic pollution, etc. No technology needed. No loss
in quality of life.

~~~
simonh
The problem with that is that most of the CO2 emissions we depend on as
individuals are beyond our control. Things like the emissions generated in
growing, processing, packaging and transporting the goods we buy, our food and
clothing, our mail, the utility resources we consume, the services we depend
on, public transport. Yes we can do thing in our daily lives but in reality
it’s a tiny fraction of our actual CO2 footprint. That’s why societal and
industrial level action, and therefor public policy is so important.

The biggest environmental issue we can affect in our daily lifestyle is
recycling and reducing household rubbish. It’s another important issue and one
where we really can make a difference in our everyday behaviour.

~~~
comicjk
You bring up "public transport" as one of the emissions sources beyond
people's control, without bringing up the biggest source which is under our
control: cars. US per capita CO2 emissions are 20 tons/year, of which a
typical passenger car is 5 tons/year. If you're worried about the carbon
footprint of your stuff...it is possible to buy less stuff.

~~~
simonh
There was a journalist in the UK that lives for 3 months, with his family,
doing everything they could manage to reduce their carbon footprint, and they
got it down by about 5%.

There are roughly 2 passenger cars per person in the US, so cars are about 12%
of emission, but even if you had no car you’d still need to travel somehow.
You’d never get your travel footprint to zero. I am not saying don’t try or
don’t bother, I’m just saying firstly we are not going to solve this with
public policy action. And second, sometimes there are other valid
environmental issues we can focus on in our personal behaviour.

~~~
FartyMcFarter
Did that journalist ever do plane trips? I recall reading that for many people
that is the single biggest thing that accounts for their emissions.

