
Scientists find massive reserves of mercury in permafrost - carapace
https://news.agu.org/press-release/scientists-find-massive-reserves-of-mercury-hidden-in-permafrost/
======
yesenadam
>"The study found approximately 793 gigagrams, or more than 15 million
gallons, of mercury is frozen in northern permafrost soil. That is roughly 10
times the amount of all human-caused mercury emissions over the last 30 years,
based on emissions estimates from 2016.

>The study also found all frozen and unfrozen soil in northern permafrost
regions contains a combined 1,656 gigagrams of mercury, making it the largest
known reservoir of mercury on the planet. This pool houses nearly twice as
much mercury as soils outside of the northern permafrost region, the ocean and
the atmosphere combined.

Gigagram? Never heard that one before.. uh a billion (US) grams? So.. a
million kilos..a thousand tonnes..a kilotonne. or 1,656 gigagrams = 1.656
million tonnes, I think. (Weird that the imperial unit is gallons, a measure
of volume I thought)

This doesn't sound good. Also I'm surprised that human mercury emissions in
the last 30 years were so high. Since the late 80s..sheesh.

~~~
infogulch
You're recalling correctly, gallon is a measure of volume. I would assume they
used density conversions just to make it into a "relatable" measure for US
readers.

But there is no US-gram. The SI unit for mass is the kilogram, (for which
"kilo" is shorthand), where kilo- and giga- are standard SI prefixes. Units
and prefixes are designed to be mixed and matched, so gigagram is just as
valid as kilogram, even if it's more rare.

Edit: thank you userbinator for the base unit correction. I've edited above to
not be blatantly wrong.

~~~
userbinator
_The SI unit for mass is the gram, (not "kilo" which is just shorthand for
kilogram, which is just commonly used because it's relatable)_

The SI base unit for mass _is_ actually the kilogram. It is memorable and
notable for being the only base unit that already has a prefix.

~~~
infogulch
Oh, thank you for the correction, not sure why I forgot that.

> the only base unit that already has a prefix.

That is interesting. So is kg actually _not_ designed to work with other
prefixes? Is it supposed to be megakilogram vs gigagram? Or are you just
supposed to convert to something else or always use scientific notation? Or am
I right about gigagram being valid, but for the wrong reasons?

~~~
NamTaf
No, it's supposed to be used just like others, it just has a prefix at its
'base' unit. Milligram and Megagram would indeed be technically right, but no
one uses it (edit: in the case of megagram, thanks daveguy).

I suspect this is because, sort of like length, there's many different names
for essentailly different orders of magnitude and you'd first go to the
largest (a tonne, 1000 kg) before adding on prefixes. I suspect this many-
names factor is in turn because they're such historical things that humans
have measured and quantified since prehistory, because distance and mass are
the first 'quantities' we begin to encounter.

So instead of 793 gigagrams, I'd say 793 thousand tonnes, or 793 kilotonnes.

~~~
yesenadam
No-one uses milligram?! hehe uh.. Maybe that was a typo. What do you call that
amount?

Also, 'liter' is used only in the US I believe. You guys just won't play with
the other children, huh. :-)

edit: ah ok sorry NamTaf. Get some sleep!

~~~
feikname
I do not have any sources, but I'm pretty sure litre (or liter) is used very
extensively, across the ocidental world at least, including Australia. What
country are you from?

~~~
yesenadam
Yes, liter or litre is used across the world. 'Liter' is used only in the US I
believe.

~~~
knicholes
I'm pretty sure that the only time I use 'liter' is for soda pop. I'm from the
US.

------
azeotropic
793 gigagrams in how many grams of permafrost?

From the paper's estimate of the concentration in soil (43ng mercury per gram
of soil) this mercury is dispersed in 18 exagrams of soil.

For scale, the concentration of mercury in permafrost is about an order of
magnitude less than what is found in tuna, and about the same as what is found
in haddock or mackerel. (At least according to Wikipedia:
[https://en.m.wikipedia.org/wiki/Mercury_in_fish](https://en.m.wikipedia.org/wiki/Mercury_in_fish))

~~~
yesenadam
Does an 'exagram' mean anything to you? Doesn't to me. Those weights are
meaningless in that format, except to geologists I suppose. (Please no-one
explain to me what 'exa-' means, I don't mean that!)

Anyway, it says the median is 43±30ng/g, the mean 62±35ng/g. Why wouldn't they
use the mean in the main results? That's what I imagine would give the
'concentration of mercury', the average (mean) concentration.

Reading the method, it's a huge guesstimate in a dozen ways, even much further
than I would have thought. Guess that's how they get 13-73ng/g. I wonder how
they have any confidence in the error range.

~~~
yesenadam
late edit: Could downvoters please explain why? Thanks.

~~~
yesenadam
Wow, ok, I give up. Fuck trying to understand why people downvote on here.

~~~
grzm
Dunno about the other ones, but this one (the one you're responding to) could
be because it's against the guidelines:

> _" Please don't comment about the voting on comments. It never does any
> good, and it makes boring reading."_

[https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)

It's best to just roll with it, I think. Follow the guidelines and post as
substantively as you can. The population of HN is large and diverse and you're
unlikely to be able to figure out why each and every downvote (or upvote, for
that matter) is handed out, and even if you could, you may not agree with why
they did so or think it’s fair. They can be useful as a guide and an
opportunity to imagine how the comment may come across differently than you
intend. But at the end of the day, it's the nature of the beast. Use what you
find useful and let the rest slide.

------
rfujikawa
Sounds like a job for Cody of Codyslab. I see "Recovering Mercury From
Permafrost" videos in our future...

~~~
ageofwant
Cody extracts mercury by roasting cinnabar which is a mineral rich in HgS - or
maybe HgS is called cinnabar - I forget.

I'm assuming this mercury is also bounded, and not lying around in pools of
Hg. Hg is less toxic than Pb, and yet the government is OK with people
shooting thousands of kilograms of the stuff over swamps and waterways and
food crop fields.

~~~
madaxe_again
It's going to be biological mercury - from bioaccumulation in top predator
tissue which ends up frozen and inert in the permafrost when the top predators
die.

The thing that makes this _really_ nasty is that biological mercury is most
commonly methylmercury - which makes free mercury look like delicious gravy.
It's very readily absorbed by tissues, and doesn't leave.

God help us if it's acquired a second methyl group through tens of thousands
of years of incredibly slow decomposition - dimethylmercury is pretty much the
most toxic thing we know of.

~~~
refurb
I think inferring bioaccumulation is the biggest source is a bit of a stretch.
Naturally occurring processes can result in organomercury compounds in soil as
well.[1]

[1][https://en.wikipedia.org/wiki/Methylmercury#Environmental_so...](https://en.wikipedia.org/wiki/Methylmercury#Environmental_sources)

------
jwfxpr
Well, climate scientists have been predicting it for years, but the evidence
is finally in: the mercury is definitely rising.

------
EarthIsHome
Scary stuff:

> The study reveals northern permafrost soils are the largest reservoir of
> mercury on the planet, storing nearly twice as much mercury as all other
> soils, the ocean and the atmosphere combined.

And the permafrost is thawing thanks to climate change.

> “There’s a significant social and human health aspect to this study,”
> Sebestyen said. “The consequences of this mercury being released into the
> environment are potentially huge because mercury has health effects on
> organisms and can travel up the food chain, adversely affecting native and
> other communities.”

------
darfo
How did it get there? I was disappointed that wasn't mentioned.

~~~
madaxe_again
Dead predators (seals, cats, etc.), which fed on other predators - probably
fish - which accumulate mercury through eating other aquatic organisms. This
is why tuna has relatively high levels of mercury, and humans moreso - once
it's in you, it tends not to leave. The higher up the food chain you are, the
more mercury you consume and retain.

The reason there's such an accumulation in the permafrost is that predators
which die up there don't decompose, they just freeze. Sure, they might get
snacked on by scavengers before they freeze, but those scavengers then get
eaten by predators, resulting in the vast majority of organic tissue and
therefore mercury in the arctic ending up as frozen organic matter. The
permafrost comprises incredibly vast quantities of organic material, animal
and plant, and not much else. Elsewhere on earth, decomposition happens, flies
eat the rotting meat, the mercury gets scattered to the four winds, and goes
back into the food chain.

It's also the same reason for the vast quantities of methane that are
beginning to be released - huge quantities of organic matter that's been in
the deep freeze, decomposing.

The arctic is going to be the biggest charnel pit the earth has ever seen.

~~~
jxub
Scary but amazing stuff, thanks for taking time to explain!

------
Someone
”mercury is _frozen_ in northern permafrost soil”

Is it? From a quick scan, I couldn’t find any reference to mercury compounds
in the paper, and pure Mercury has a freezing point of -38,83 °C.

Seems you could crush the frozen ground, and the Mercury would drop out. Also,
if that’s the case, how much of it would simply drop deeper into the ground
when the permafrost thaws?

~~~
MattHeard
Even if the mercury remains a liquid, it could still pose a risk if it is
currently trapped within ice but flows into waterways when released from the
thawed ice.

~~~
aardvark291
It's almost certainly not in the form of elemental mercury (which would be a
liquid), but a solid mercury compound.

------
johnalamos
Just change it to Gold. $_$

[https://www.wikihow.com/Make-Gold-from-Mercury](https://www.wikihow.com/Make-
Gold-from-Mercury)

------
xq3000
Does it mean that as the global warming progresses all that mercury will
mobilize and Earth will poison itself...?

------
randomdrake
Study: Permafrost Stores a Globally Significant Amount of Mercury

Citation: Schuster, Paul F.; Schaefer, Kevin M.; Aiken, George R.; Antweiler,
Ronald C.; Dewild, John F.; Gryziec, Joshua D.; Gusmeroli, Alessio; Hugelius,
Gustaf; Jafarov, Elchin; Krabbenhoft, David P.; Liu, Lin; Herman-Mercer,
Nicole; Mu, Cuicui; Roth, David A.; Schaefer, Tim; Striegl, Robert G.;
Wickland, Kimberly P.; Zhang, Tingjun. Geophysical Research Letters, 45.

Link:
[https://doi.org/10.1002/2017GL075571](https://doi.org/10.1002/2017GL075571)

DOI: 10.1002/2017GL075571

Abstract: Changing climate in northern regions is causing permafrost to thaw
with major implications for the global mercury (Hg) cycle. We estimated Hg in
permafrost regions based on in situ measurements of sediment total mercury
(STHg), soil organic carbon (SOC), and the Hg to carbon ratio (RHgC) combined
with maps of soil carbon. We measured a median STHg of 43 ± 30 ng Hg g soil−1
and a median RHgC of 1.6 ± 0.9 μg Hg g C−1, consistent with published results
of STHg for tundra soils and 11,000 measurements from 4,926 temperate,
nonpermafrost sites in North America and Eurasia. We estimate that the
Northern Hemisphere permafrost regions contain 1,656 ± 962 Gg Hg, of which 793
± 461 Gg Hg is frozen in permafrost. Permafrost soils store nearly twice as
much Hg as all other soils, the ocean, and the atmosphere combined, and this
Hg is vulnerable to release as permafrost thaws over the next century.
Existing estimates greatly underestimate Hg in permafrost soils, indicating a
need to reevaluate the role of the Arctic regions in the global Hg cycle.

~~~
dang
It's fine to post links to the relevant paper, but could you please stop
pasting bibliographic boilerplate into HN threads? I'm sure your intention is
good, but the purpose of HN threads is thoughtful conversation, and this is
not that.

~~~
randomdrake
Sure. Thoughtful conversation and adding to it is definitely part of the
intention; not trying to be a bother. Happy to adjust and try to keep
contributing if you could be so kind as to let me know what would be preferred
instead of a citation like this.

~~~
dizzystar
I think the poster was irritated with the long citation list and other
extraneous items.

Just share a link and a part of the abstract, or do a summary.

------
blubb-fish
using gallons as a unit - that's ri-di-cu-lous

------
GEBBL
To be honest, at this stage, it's just another thing to add to the ever
growing list of things that could potentially kill us.

~~~
joantune
this one is avoidable though

