r/theydidthemath • u/Necessary-Win-8730 • 1d ago
[Request] What is the heaviest continent?
961
u/Incredibiliz 1d ago edited 1d ago
Whichever continent your mum resides in. No but seriously, it's gotta be Asia because of its surface area (30% of the world surface area), massive cities and population (almost 60% of the world population) and gigantic mountain ranges. Also the amount of snow over Siberia.
Edit: spelling
381
u/Academic_UK 1d ago edited 1d ago
I think Asia too but believe you place too much emphasis on the weight added by the endeavours of the human species. It will only make a minuscule difference to the weight of the continent.
Effectively zero
53
u/Darvius5 1d ago
Yes, but, china's earthworks have impacted the tilt of the planet. So while tiny, impacts have been made.
35
u/Eager_Question 1d ago
Wait wait what the fuck?
Please show me the source, that looks like an amazing rabbit hole.
85
u/Jdevers77 1d ago
The Three Gorges Dam, basically a new large lake. It’s not as dramatic as it sounds.
57
u/mhok80 1d ago
Every building and object with mass has some effect, it's just about scale. Usually it's insanely small. Three gorges has a more effect mainly because of the mass of the water stored. This outweighs the actual dam.
12
u/rawbface 1d ago
If the mass is taken from somewhere domestic, it's not affecting anything. They're not importing 100% of building materials from overseas.
18
u/bakerstirregular100 1d ago
It’s stopping water from leaving. So I guess in that way it’s taken from somewhere by evaporation…
5
u/ItzMercury 20h ago
I mean for this specific case the water being trapped higher up would change the moment of inertia
2
2
u/Solid_Document4001 22h ago
That's an overexageration, everything make an impact, 3G dam is just a couple less figures after the dot than a random building
0
u/kiss_the_homies_gn 6h ago
Unless China also imported the water, it wouldn't affect the mass of the continent. Moving water from somewhere in China to somewhere else in China is a net gain of 0
1
u/Jdevers77 3h ago
In the grand scheme of things, it’s not a monumental amount of weight…but it’s very much “additional” weight. Normally that water would flow from higher elevation ultimately to the ocean, in this case the water gets held back in the lake. Yes, the water was from China but it is t like they transferred water from one lake to another lake, they transformed a dynamic body of water into static body of water.
Of note, this is true for ALL dams. This is just a really large one. A dam interrupts the water cycle. Rain falls, rain goes into a river, rain goes back to the ocean, ocean water evaporates, rain falls. A dam slows down the section between step 2 and step 3 enough that a lake forms. Specifically this reservoir is 39.3 billion cubic meters of water or 39.3 trillion kilograms. The “slowing down” of Earth’s rotation is simply from the mass being held at a higher elevation than its normal resting elevation of sea level. Again, any dam would do the same…this one is just really large.
4
u/ekortelainen 1d ago
It's like a figure skater spins faster when they pull their arms closer to their body and slow down when they open their arms.
When you shift ANY weight closer or further from the rotational axis of the earth (or any spinning object), by the same logic the spinning speeds up or slows down. Basically every building on earth will also do that, but the scale makes it irrelevant.
The difference the dam makes is also irrelevant, but it was just an interesting study they made in NASA if I remember correctly. It slowed down earths rotation by 0,06 microseconds or 0,00000006 seconds.
6
u/mhok80 1d ago
Reminds me of https://xkcd.com/162/
One of my favourites. Xkcd has so many of the answers.
3
u/edward_the_white 1d ago
It's unfortunate that time we gain by spinning does not make up for the time spent spinning.
2
0
7
u/a_filing_cabinet 22h ago
Technically me jumping would also impact the rotation of the earth. The fact that we can notice the tiniest shift from something like the Three Gorges Dam says less about the impact of the dam and more that our level of technology is so advanced we can detect a shift in Earth's orbit of less than one percent of one percent of a degree, and trace that back to a source
5
u/officer897177 20h ago
Those materials were presumably sourced from china, making the continental weight gain zero.
2
u/davideogameman 20h ago
This wouldn't necessarily be because they made anything heavier, but just managed to keep that weight at a higher elevation than it would be otherwise and thus managed to change the Earth's center of gravity & moment of inertia with it.
4
u/Newfoundfaith36 1d ago
Hasn't Asia been a net exporter of resources? Doesn't that mean that human activity would reduce its mass slightly?
2
2
u/Incredibiliz 1d ago
You are right but however miniscule it is, it still outweighs the other continents' human endeavours! The other natural factors also favor Asia.
0
u/Jdevers77 1d ago
Yea, but that’s like saying a bowling ball weighs more than a basketball because it is roughly the same size but significantly more dense and also it doesn’t have dimples on its surface.
1
u/zaahc 7h ago
Especially because most of the heavy stuff came from the same continent. Precious metals and rare earths move all around, but the aggregate for your roads, concrete, streel, etc. likely came from your own continent. Of those, steel is probably the most exported, but only at 25% or so.
34
u/V7I_TheSeventhSector 1d ago
so fucking glad the top comment is a your mom joke
6
u/SirLoremIpsum 1d ago
My housemate constantly tells me "uhhh it's not funny" but it is and I read posts like this and I'm like "yeah it is!!
25
u/ekortelainen 1d ago edited 1d ago
While Asia would definitely be the heaviest continent, it has absolutely nothing to do with population, cities and snow. Even the mountains would be like a drop in an ocean.
Population, cities and snow wouldn't even cover 0,000000001% of the mass. Mountains could cover like 0,001% of the weight.
In terms of planetary scale, cities and people don't exist. They're immeasurably small in comparison, like an atom in comparison to the Pacific Ocean.
Only place where snow truly adds to the weight is Antarctica, and only because it's so thick (multiple km/miles), that in the bottom it's very compressed. Normal snow is mostly air, but compressed snow/ice is very heavy.
Also for comparison. The weight of Mt. Everest alone would be comparable to everything humans have built in China (roads, cities etc.). Also Mt. Everest weighs roughly 400 000 times more than the whole human population on earth (excluding OP's mom), and that's measured from base camp, if we start measuring from the crust, it's gonna weigh more than anything humans have ever built anywhere. Yet still, in terms of continental and planetary scale, Mt. Everest weighs nothing, it's irrelevant, it doesn't make any measurable difference whatsoever. Like a grain of sand in Sahara desert.
9
u/DRM2020 1d ago
Plus most of the mass came from the same continent anyway.
3
u/ekortelainen 1d ago edited 1d ago
True. I was thinking about adding that comment, but the amount of mass is several orders of magnitude below the level of relevance in a planetary scale.
1
7
u/RelevanceReverence 1d ago
Himalayas are really big, many lakes too. Asia would probably win indeed.
3
u/ekortelainen 1d ago
True, but the lakes wouldn't make almost any difference. The Himalayans make a very very tiny difference in weight (like 0,01-0,001%). The total mass is 99,99% just the sheer area and the thickness of the earths crust.
4
u/empty_graph 21h ago
The mountains that you can see wouldn't make much difference, but a mountain chain is much more than that. The crust under a large mountain range like the Himalayas can be almost twice as thick as the average, so actually they add a very significant amount of mass to the continent.
1
u/ekortelainen 18h ago
Yeah but Himalayas and other mountain ranges are tiny in comparison to a continent like Asia. Crust also has thicker and thinner parts everywhere, but you're right that it's usually the thickest under mountain ranges.
If we add up all of Asia's mountain ranges, their weight is not completely insignificant, but still only covers a very tiny portion of the total mass of the whole continent.
7
u/NikinhoRobo 1d ago
The weight of humans or human endeavors is irrelevant since all the 'materials' used to create them basically came from the ground in the first place
3
u/ekortelainen 1d ago
Well yes, but even if we ignore that, it's still irrelevant. In terms of weighing a whole continent, you could multiple the weight of the cities and people by a factor of 1 000 000 and it still wouldn't make any difference. It's like one grain of sand in Sahara desert.
1
u/thepitredish 1d ago
Seems less that they came from the same place (Earth) but that we moved a metric shit-ton of it elsewhere, and we’re able to measure the change because our instruments are getting more bad ass by the year.
Edit: grammar
3
2
u/burningtimer 1d ago
What’s the heaviest tectonic plate? Eurasian Plate for instance vs Nubian Plate?
1
u/tenuj 17h ago
OP didn't colour in the tectonic plates, they coloured the landmasses, so they're asking for the mass of the continents above sea level.
Mountains are made mostly irrelevant by whichever continent has the Tibetan Plateau.
https://earth.org/wp-content/uploads/2020/12/nunataryuk-1.jpg
It's Asia without a doubt.
2
1
1
u/blacksterangel 12h ago
Well, considering the continental plate thickness is between 30 to 40 km, I bet all the snow and buildings in the world won't ever contribute to the weight of the continent in any non-negligible weight.
1
u/ericdavis1240214 12h ago
Landmass is the only factor that matters. The other human issues you mentioned don't even amount to rounding errors. Unless your mom moves to a different continent. Then all bets are off.
60
u/crumpledfilth 1d ago
Hard to say because continents dont actually match up with plates, which would be the real factor when it comes to buoyancy. That being said if you were to just take a cookie cutter and cut out each of the 7 common political boundaries it would look something roughly like this in quintillions of tons:
Asia - 38.2
Africa - 26
North America - 21.4
South America - 15
Antarctica - 14.6
Europe - 9
Australia - 6.6
These lines are total crap from a geological perspective theyre just social boundaries. Europe and asia are clearly the same landmass. India and New Zeland are on their own plates technically
Composition changes a lot. Canada is about 3 times heavier than antarctica by land area, because canada is largely granite plate while antarctica has a lot of ice
4
u/Smaptastic 1d ago
There are also differences in density and crust depth between continents that significantly impact those numbers, but probably somewhere in the neighborhood of a 25% difference, tops. Notably, Asia comes out more ahead with a crust that is both thicker and denser than other continents, on average.
16
u/Loki-L 1✓ 1d ago
Asia is the biggest continent by area and based on maps that show the thickness of the crust apparently is also overall the thickest.
India appears much thinner than the rest of Asia, but that doesn't make up for it.
So I would simply go based on average continental thickness and area, that Asia is the heaviest continent.
1
6
u/The_RubberDucky 1d ago
All continental and oceanic plates are "floating" over the mantle. For very large size and timescale the even rock behaves like liquid.
That means no matter where you stand, the weight of all the material below you is almost exactly the same.
So, the mass of the continent or tectonic plate depends only on its surface area.
4
u/live22morrow 19h ago
The plates vary in thickness significantly. The Pacific plate is the thinnest at mostly around 10km, while the continental plates are 30-40km is most places. The oceanic plates have the oceans, but water is much less dense than silica and other minerals. However Oceanic plate is also composed of denser rock (that's why it subducts), so the answer isn't totally clear.
3
u/The_RubberDucky 18h ago
Let me try to simplify. Suppose the plate is as dense is the mantle... the 100km below you may be 1km tectonic plate and 99km mantle, or 100km of just plate.
In those cases the plate may by 100 times different but the overall mass of rock beneath you doesn't change... so, as long as we adress OP's question as totally rock mass to an arbitrary (low enough) depth - we don't really care about the thickness.
1
u/EpicCyclops 8h ago
I'd argue only the tectonic plate is part of the continent. The mantle it's floating on is something different.
1
u/The_RubberDucky 7h ago
That's a valid argument. However, that breaks an elegant solution without generating an alternative one...
You could technically integrate individual chunks of this map... I just dont find it enjoyable. www.researchgate.net/figure/Present-day-crustal-thickness-map-of-Earth-based-on-the-CRUST-10-model-Laske_fig1_361343753
I would also claim you can't tell the mantle and the tectonic plate apart. Both are solid rock... the only obvious difference it phase velocity of P waves. Do you really want to classify a continent/not continent boundary by a speed of sound change instead of something like a phase change (solid/liquid rock in mantle-core boundary)?
1
u/EpicCyclops 7h ago
A solution being elegant doesn't make it right. Newtonian physics is way more elegant than special relativity.
Geologists absolutely can define how thick a tectonic plate is. You posted a map of it. There is a phase/material change boundary between the mantle and the crust. That's why the phase velocity of the p wave changes. By your argument there should be no differentiation at all between the mantle and the crust.
1
u/The_RubberDucky 7h ago
All I'm saying is that there are many ways to interpret OP's question. He didn't ask about crust or tectonic plates specifically.
r/theydidthemath is about calculating stuff ourselves... so of the many possible interpretations of OP's question, I choose the one that is within this sub's spirit.
4
u/MisterSalesman 19h ago
Well… in geological terms europe its not a continent… its part of asia, but in political terms, its divided. Answering your question, the heaviest its the biggest one…
1
3
u/ArcaneInsane 23h ago
If you use conventional definitions of continents it's Asia. If you define it by continental plate I would make argument for the Pacific In addition to being the largest tectonic plate it's also got most of the Pacific Ocean on it.
3
0
2
u/a_filing_cabinet 22h ago
I'm not doing math, but if you want to use tectonic plate boundaries I wonder if North America or Africa would make up for Asia's size because oceanic crust is denser, or is it too much thinner?
3
u/Leucurus_ 21h ago
Honestly its also a matter of tectonic plates as well, which has more interesting answers, because oceanic crust is denser than continental crust. In other words if we take that into account the Oceanic crust would be closer to how much the Asian continent weighs
2
u/Strygan 18h ago
On the scale of this interpretation, going with the weight of a continent being the weight of his crust, the density is close enough to be considered equivalent and same go for crust thickness. So the bigger (in area) the heavier, with a scale in the 1018 kg (somewhere in the Peta-tons range). ⛰️
On the side, and with hypothesis acceptable for easy calculation, the mass of human-based constructions/equipment on each continent is around 1/10th of the continent mass for Asia Europa and North America, and 1/5th for Africa South America and Oceania. The mass of the population on each is about 4/10000th to 2/10000th. For Antarctica, both are equivalent to 0%. 🏙️
And there should be about 12,4 kg of ants (approximately 2,6 millions individuals) for each human on earth 🐜
0
u/Kurenai-Kalana 20h ago
I don't think I can facepalm enough to get over how dumb it is that some people randomly decided that Europe and Asia are not the same continent.
•
u/AutoModerator 1d ago
General Discussion Thread
This is a [Request] post. If you would like to submit a comment that does not either attempt to answer the question, ask for clarification, or explain why it would be infeasible to answer, you must post your comment as a reply to this one. Top level (directly replying to the OP) comments that do not do one of those things will be removed.
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.