Scientists find massive reserves of mercury in permafrost
news.agu.org
news.agu.org
>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.
It is volume. The density of mercury is 13.69 g/cm3 and thus 793E9 grams is 5.8E7 litres, or 1.5E7 gallons. "more than 15 million gallons" is correct.
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.
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.
> 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?
Gigagram just seems exotic in the same way that megameter does - it's perfectly correct and understandable, it's just rarely necessary.
https://en.m.wikipedia.org/wiki/Centimetre%E2%80%93gram%E2%8...
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.
Also common: micrograms and microliters.
Per my latter comment, it's because we don't really deal with everyday words for masses smaller than a gram, but we do for those bigger. It still holds that as far as I can think, people will go to the closest 'common term' word and then use prefixes to bridge the remaining gap (milligram, megatonne)
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!
[1] https://www.duden.de/suchen/dudenonline/Liter
[2] http://slovniky.korpus.sk/?w=liter
I think it's the same in Slovenian, Hungarian, Serbian (litar?), Norwegian and Swedish.
This question of whether there's a meaningful send in which the base unit is the kilogram and not the gram really confuses people and I don't know what the answer is. People eagerly proclaim (a) it has something to do with French historical convention (but, they admit when pressed, this gives it no non-trivial meaning today) or (b) it has to do with the size of the actual reference weight in France (which doesn't make sense because the second was never an object, and a meter no longer is represented by an object yet we still call it a base unit).
The only non-trivial interpretation I've heard (although it is still silly) is that the kilogram is the base unit in the sense that adding "kilo" to gram makes the derived units like the Newton the simplest. (You could define a Newton in terms of grams and, say, kilometers and seconds, or meters and milliseconds, but this would end up disturbing the other derived units even worse.) But of course, this is just a statement about the derived units.
"The kilogram is the International System of Units (SI) unit for mass. It is the only remaining base unit to be defined by a physical object. All standards of mass must ultimately be traceable to this one object, a cylinder of platinum-iridium alloy kept at the International Bureau of Weights and Measures (BIPM) in France"
If the President issues a statement that says "the base unit of the US is the furlong", but nothing else about the US or its system of measurements changes, this is a contentless statement. If someone else asks "but what does it actually mean for the furlong, as opposed to the inch, to be the base unit?", pointing them to the President's statement does not help.
(Remember, saying "the kilogram is the base unit" cannot refer to the fact that the mass object in France weighs a kilogram, not a gram, because people also say "the meter and the second are base units", neither of which are physically instantiated anywhere.)
As an mechanical engineer educated in the UK the base unit would be kg but you would use ax10^n [kg] to denote mass.
Love the last paragraph:
The decision of the Republican government may have been politically motivated; after all, these were the same people who condemned Lavoisier to the guillotine. In any case, we are now stuck with the infelicity of a base unit whose name has a "prefix".
Hey, it's still simpler than the American system.
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)
Could an order of magnitude less actually be a lot if you look at it that way? Since the permafrost would just be passively accumulating, as opposed to actively in a way which only something living can do.
Yes. This is called biomagnification. Basically, animals absorb heavy metals that are in the food they eat, but don't have an efficient way of excreting it again. Mainly since these metals are bound so they're fat soluble, not water soluble. The higher up in the food chain, the worse it gets.
Well from the one part is sounds like the concentration is normal:
>> Schuster and his colleagues found their measurements were consistent with published data on mercury in non-permafrost and permafrost soils from thousands of other sites worldwide.
Once you realize that, the whole thing becomes a big alarmist scare. If the arctic melts that doesn't mean the mercury is going to suddenly migrate into the rest of the world. It will probably be taken up in arctic plants and wildlife in the same proportions it exists everywhere else. But they seem to want us to think this is some new lurking scary demon of climate change that's going to come get us.
I was hoping to read something interesting, like a hypothesis about why mercury was concentrated in the arctic but all I got was a finding that it's the same as everywhere else.
I am curious if you are an expert in this field and know this to be true, or if you are making a quick assumption from a layman's understanding.
Reading the full text: http://onlinelibrary.wiley.com/doi/10.1002/2017GL075571/full Where there is more context to the quote about their measurements being consistent with non permafrost sites, and the discussion about active layer vs permafrost layers and mercury cycles, it is not clear to me that you take is correct.
It would be wonderful if someone knowledgeable could chime in.
I was just going mainly on that one paragraph which seems rather benign. It would be really nice to understand why they think it's not.
That 30-50ng/g is the concentration in uncontaminated temperate soil.
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.
You just need the density of permafrost and then you can compute the volume from the exagram value, and depending on how thick you make it you get back either the surface of northern Canada and Siberia or you get a really really tall tower of permafrost that reaches into low earth orbit :-).
> I wonder how they have any confidence in the error range.
It is my understanding that there are many many core samples at various locations in the permafrost to understand its nature and make up. My guess would be that they derive the error ranges using the change in concentrations between all of the sample points leading them to a median and mean difference in concentration samples as their base set.
> "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
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.
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.
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.
[1]https://en.wikipedia.org/wiki/Methylmercury#Environmental_so...
I'm not sure that the bismuth and tungsten and other heavier than steel shot that has partly replaced lead is a whole lot better, though...
Edit for a plug: Don't throw away NiCd batteries folks! Recycle them properly!
I bought these nickel free stainless steel pans, because apparently stainless steel has nickel in it to make it shinier. I had to buy three different "nickel free" belt buckles (don't trust random Amazon products to be free of an allergen, even if they claim it!) before I got one that doesn't make my skin break out, and I have to wear plastic glasses because my skin and the metal on glasses doesn't play nice. Even the rivets in some jeans cause problems.
Nickel is just too useful (and pre-existing in a lot of metal ores, I think) to stop using it, despite the fact that a large percentage of people are allergic to it.
> 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.”
> Mercury accumulates in aquatic and terrestrial food chains [...]
and:
> [...] trapped in permafrost [...] since the last Ice Age.
But in permafrost, it is quickly fixed by humidity and ice, and it isn't returned to the oceans by a constant flow of water?
> Environmental scientists at Harvard have discovered that the Arctic accumulation of mercury ... is caused by both atmospheric forces and the flow of circumpolar rivers that carry the element north into the Arctic Ocean.
[1] also is a pretty good article on the effects of mercury on wildlife.
There also is mentioning of possible pathways to the north here: [3] - unlike [2] they claim it's mostly through the atmosphere though.
> From our observation site north of Alaska’s Brooks Range, we determined that gaseous elemental mercury in the atmosphere is the dominant source of Arctic mercury. We calculated that it accounted for 70 percent of the mercury that finds its way into tundra soil.
[0] https://news.nationalgeographic.com/news/2010/12/101203-homo...
[1] http://e360.yale.edu/features/mercurys_silent_toll_on_the_wo...
[2] https://www.hsph.harvard.edu/news/press-releases/arctic-rive...
[3] https://www.scientificamerican.com/article/mercury-from-indu...
"If the mercury is transported across waterways, it could be taken up by microorganisms and transformed into methylmercury, he said."
"Mercury released into the atmosphere can travel large distances and could affect communities and ecosystems thousands of miles away from the release site, he said."
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.
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?
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
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.
This information is easy to get for anyone who wants it, particularly if someone has posted a link to it. There's no need to inline the content.
Just share a link and a part of the abstract, or do a summary.
p.s. We really do appreciate the intent.
BTW, good job on your blog randomdrake!
I just recently read about iron fertilization as a potential tool to fight climate change, can't believe I'd never read about it before. Potential downsides but still very interesting, especially if economical.
https://en.m.wikipedia.org/wiki/Iron_fertilization
I strayed far away from the research side of things back in school, but I wish we had more bold disrupters or shapers in the field. I know it's antithetical to the personality, skills, structure, and honestly the traits to succeed in the field but someone who'd be bold, sway the media, public opinion and congress with visions for deep funding and just dive in and trailblaze and get stuff done instead of so much research. I dont keep up with the field and Im sure this is extremely naive but just my thoughts.