Cecil, great stuff.
Brings up an interesting side-thing, if there are so many more of us today, than say, 3 million years ago, than the surface of the earth has more weight on it, and the insides have less.?. I know, I know, it’s very insignificant, but still…
There are more of us, but a heck of a lot less bison, passanger pigeons, mastadons, rhinos, and Madagascar silver cloud-rats. Kinda balances off in terms of biomass, eh?
Uh, im no expert, (cough, cough) but I would guess, that people are made from stuff on the earth already, and grow bigger when we eat food created out of elements here on earth, and thus the amount of people on earth have no effect on the planets weight.
However, we are constantly being bombarded by meteors, space dust, and (according to x-files) aliens and their spacecraft. This, of course would make the earth heavier.
Depends, really, on how much weight we humans are sending into space, though. (rockets, satellites, etc) If forced to guess, i would say earth is getting hevier, due to all the space dust and meteors being drawn into the atmosphere by the earths gravity.
Then again, one must consider portals into other diminsions, gifts from heaven, etc.
can get confusing for a feeb.
Well no because you cant make a planet heavier by recombing the molecules and atoms already there. For instance, take a block of clay, make 100 balls. Seems like a lot more things but it’s still the same amount of clay (Sorry, thats the only analogy i could think of at the moment). But, i would gamble that the earth is getting heavier because of all the space junk we pick up while we travel through space.
ugh…damn typos…recombing = recombining
Ok, for clarity, the Earth is getting heavier, some of the replys seem to feel this post is in debate of that fact.
Now in reference to the secondary question you want to discuss. The amount of biomass is likely much lower today than in the past. Not because of bison, owls, whales and such, because the expansion of people is probably close to equating that. The true loss is in the reduction of dense forests and rainforests. Their biomass is staggering compared to any density of animal populace.
To the meat of the question.
Correcting this question for accuracy; Does a larger amount of biomas on the surface equate to less mass inside it?
Well, that is a question of definition. Do you consider the crust as the outside and the mantle and in the inside? Or do you just consider those things above the plane of the soil as being on it? Makes for a difficult assessment of the plant life, eh?
If you consider the plane of the soil being things “on the surface” then yes, there is less stuff on the inside and more on the outside, and vice versa.
The interesting question is the other perspective. Now no one can say for certain, if this is true, but heres a theory, that is pretty well founded. If you consider the crust the outside and the mantle/core the inside then no the mass doesn’t change. If you neglect the effects of the Earths cooling (in respect to the inside), the thickness of the crust stays the same. The crust “floats” on the mantle and is governed by the effects of Archemedes Principle. So if the mass on the surface of the crust (from people, biomass, or space debris) changes the crust floats higher or lower in that mantle. The greater submerged volume will be melted and returned to the mantle.
The facts expressed here belong to everybody, the opinions to me. The distinction is yours to draw…
Omniscient; BAG
Omni - nice text. I was thinking of the Crust / Multen Lava as outside and inside. It’s nice to know it floats, that way we don’t have to wory about drowning in extremely hot liquid.
It is an interesting thing, that we only reshape the very thin layer of the surface of the earth, and we are not reaching for anything too deep.
Archimedes Principle: I think that’s the whole why-boats-float weight displacement thing, right? Just making sure (damned failing memory).
anyway, i think the total biomass is probably the same as before, or perhaps slightly higher. you’re right that vegetation greatly outweighs animals, of course, but their biomass is simply recycled into other forms (microbes, replacement vegetation, etc.) when they die. in general, ‘edible’ biomolecules that aren’t in living things are eventually grabbed up by organisms and made into biomass again.
i think that the earth’s biomass is probably increasing due to biomolecules in space debris falling on the earth. unless you’re right about the earth’s crust remaining the same thickness, in which case biomass near the bottom the of the crust falls into the way-too-hot mantle and dies, therefore keeping the biomass the same.
come to think of it, it’s probably a function of the earth’s average temperature, since the higher it is (to a point, of course) the more landmass there is that can sustain life. case in point: i’m guessing antarctica has lots of ‘unused’ biomass because so few things live there.
yeah, i think i’ll stick with that one
My thoughts on biomass, halfway informed:
Someone suggested that “edible” molecules – i.e., those in living organisms – get grabbed up pretty quickly when those organisms die. There are some exceptions to this rule:
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Petroleum and other fossil-fuels. The plants and critters that died some tens of millions of years ago went from On Top of the planet to Under the Surface of the planet. Petroleum reserves seem to be common-sensibly inside the earth; the death of those dinosaurs, therefore, made the earth heavier.
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Some death at sea (although rarely): when fish and plankton and other sealife die, they usually sink. And usually something gobbles them up before they land, and usually if they land something crawls over and gobbles them up. But sometimes they can die over deep deep ocean trenches, and (I believe) we don’t know of any life that lives on the floor of the deepest trenches.
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I’m not certain about this one, how it plays out. Large-scale agricultural practices result in massive erosion – viz. the Dust Bowl of the 1930s. And, bizarre as it might seem, your average prairie contains more biomass than your average rainforest: prairie soil runs extremely deep, unlike rainforest soil, and is chock full of life. Now, I’m not sure what happens when that soil eventually reaches the sea: does it suffocate sea life? or does the sea life chow down on the ex-prairie?
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There’s some (not definitive, but some) evidence that depletions in ozone are resulting in increased UV damage to phytoplankton. Phytoplankton act as a massive carbon sink – which is to say, they gobble up lots of those organic compounds mentioned earlier. Their death isn’t, I think, significant in itself, but is very important in combination with
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Finally, as someone mentioned, the earth is losing significant biomass through the burning of rainforests. The carbon in these trees is converted into carbon dioxide, and currently no one is sure what’s happening with all that CO2. Is it gonna be eaten by phytoplankton and result in big algal blooms at sea? Are the dead phytoplankton going to be revived by a breath of fresh (to them) air? Or will the CO2’s release trigger a vicious circle – as more trees are burned, there are fewer trees to absorb CO2? If something like the latter happens, then we’re definitely talking a reduction in biomass.
Just my thoughts.
Wow, you two sure muddled this thing up. I’m sorry to say that most of your guesses are wrong based on my definitions.
Lets clear a couple of things up. First biomass is defined as living material by M-W. Now some biologists and geologist may refine this abit, but for this discussion i’m gonna stick with that. So guys this eliminates any discussion of fossil fuels. (Not to mention according to the definition stated before they are included in the crust, ergo are “on” the earth.)
FYI, Archimedes Principle states that the mass of the volume of fluid displaced is equal to the mass of the object suspended.
I’m gonna assume that the amount of animal life is constant, and I believe that that is relatively accurate. Also I’ll estimate that the vegetable matter is 10 times greater than animal (probably low, but it allows me to ignore animals).
Im fairly certain that this is wrong, I won’t claim Cecilesque certainty, but I know it is based on my understanding. Heres why. First there is no biomass on any cosmic matter. The thought that there is is simply X-files stuff. Fossils, maybe, biomatter…no. Second we need to seperate biomass from surface (crust) mass. The mass increases substantially because of space debris, and part of the crust melts. Third there is likely no biomatter below the top soil. This means that no biomass is lost to the mantle.
In summary, the biomass on the earth is simply governed by the number of living things at any point in time. Therefore the alternate definition of the plane of soil being “on” is the only time on would consider it.
Another point overlooked before is that the amount of biomass has no effect on the Archimedes effect. Even if this biomass is burned off and becomes gasses the mass on the crust is equal. Everything above the plane of the mantle acts as mass acting downward reguardless of physical state. Therefore the only change influencing the bouyancy of the crust is the addition of mass from space and the negligable loss of gas at the upper limits of the stratosphere. There are likely a few other sourses such as solar particles and such but they are low.
Withrow I don’t know how you deviated to a greenhouse discussion, but I’d like to avoid that losing battle at all costs. Also there are animals and bacteria at the lowest depths of the ocean and all dead sea life is eventually returned to biomass, generally speaking. I highly doubt that prarie even comes close to the biomass as rainforests. there is more soil, but soil is not filled with enough living matter to offset the huge density of life in the rainforest. I’d be open to supported claims, but for now I’ll disregard this.
This is all true except one point. A significant amount of biomass (wood) is preserved and removed from the life cycle. This is a loss of biomass according to the M-W definition.
I’m exhausted and likely missing some points. But I’m finished for now.
The facts expressed here belong to everybody, the opinions to me. The distinction is yours to draw…
Omniscient; BAG
I’m having a hell of a time with these quote things. I’m gonna repost to try and clear things up.
Wow, you two sure muddled this thing up. I’m sorry to say that most of your guesses
are wrong based on my definitions.
Lets clear a couple of things up. First biomass is defined as living material by M-W.
Now some biologists and geologist may refine this abit, but for this discussion i'm
gonna stick with that. So guys this eliminates any discussion of fossil fuels. (Not to
mention according to the definition stated before they are included in the crust, ergo
are "on" the earth.)
FYI, Archimedes Principle states that the mass of the volume of fluid displaced is equal
to the mass of the object suspended.
I'm gonna assume that the amount of animal life is constant, and I believe that that is
relatively accurate. Also I'll estimate that the vegetable matter is 10 times greater
than animal (probably low, but it allows me to ignore animals).
Im fairly certain that this is wrong, I won't claim Cecilesque certainty, but I know it is
based on my understanding. Heres why. First there is no biomass on any cosmic
matter. The thought that there is is simply X-files stuff. Fossils, maybe,
biomatter...no. Second we need to seperate biomass from surface (crust) mass. The
mass increases substantially because of space debris, and part of the crust melts.
Third there is likely no biomatter below the top soil. This means that no biomass is lost
to the mantle.
In summary, the biomass on the earth is simply governed by the number of living things
at any point in time. Therefore the alternate definition of the plane of soil being "on" is
the only time on would consider it.
Another point overlooked before is that the amount of biomass has no effect on the
Archimedes effect. Even if this biomass is burned off and becomes gasses the mass on
the crust is equal. Everything above the plane of the mantle acts as mass acting
downward reguardless of physical state. Therefore the only change influencing the
bouyancy of the crust is the addition of mass from space and the negligable loss of
gas at the upper limits of the stratosphere. There are likely a few other sourses such
as solar particles and such but they are low.
Withrow I don't know how you deviated to a greenhouse discussion, but I'd like to
avoid that losing battle at all costs. Also there are animals and bacteria at the lowest
depths of the ocean and all dead sea life is eventually returned to biomass, generally
speaking. I highly doubt that prarie even comes close to the biomass as rainforests.
there is more soil, but soil is not filled with enough living matter to offset the huge
density of life in the rainforest. I'd be open to supported claims, but for now I'll
disregard this.
This is all true except one point. A significant amount of biomass (wood) is preserved
and removed from the life cycle. This is a loss of biomass according to the M-W
definition.
I'm exhausted and likely missing some points. But I'm finished for now.
The facts expressed here belong to everybody, the opinions to me. The distinction is
yours to draw…
Omniscient; BAG
-
Let’s not forget relativity–the more speed, the more mass, and biomass, or the planet Earth not consisting of photons, the closer you get to the speed of light, the closer to infinite mass. The rotational speed of the Earth is absolute slowing down–I don’t know if it becomes tide-locked prior to the expansion of the sun into a red giant star–and I leave into the astronomical types wheter the expansion of the universe is slowing down. So, the Earth is losing some mass through speed loss, and outgassing. I don’t know if this offsets the additional of space junk swept up by the Earth.
Or, is this just too far off the point? -
Of course biomass is increasing. Life converts non-biomass stuff into biomass. If you take a sufficient long look at it, you start at zero biomass. Now, have we reached some steady state point for the last couple hundred million years or so? I doubt it. You’ve got several billion years of evolutionary pressure demanding that life convert non-biomass into biomass.
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Forget the rainforests. Think oceans.
That’s where the biomass is. Just as there’s a lot more ant biomass than human biomass, don’t underestimate the amount of plankton/algae/krill et cetera biomass.
Biomass is irrelevant. If Biomass increases, there is a corresponding decrease in non-biomass. And vice-versa.
Archimedes Principle is irrelevant. What matter floats where has no bearing on the total. Makes no difference to the Earth’s mass whether some subset of Earth’s matter floats on the mantle or sinks through it.
Gutrender got half the relevant equation right by considering the dust, gas, and meteorite infall on Earth.
The other half of the equation is mass lost from the upper atmosphere as energetic gas molecules (mostly hydrogen) achieve escape velocity, and as a certain amount of gas is blown free by the solar wind.
I don’t know if infall exceeds gassout, but I suspect it does. If so, the Earth is growing heavier.
Have you thanked a legitimate businessman lately?
Mark, you haven’t been reading any of this have you?
The facts expressed here belong to everybody, the opinions to me. The distinction is
yours to draw…
Omniscient; BAG
I read all of it. A question is posed in the title but is never really addressed except tangentially -notably by Omniscient. Instead the thread goes off onto the tangent proposed in the first post about human biomass, quickly expanded to all biomass, on the mistaken assumption that the fraction of the planet’s mass made up of biomass has any relevance whatsoever to the total mass of the planet. Not to mention the digression into mantle floatation.
Topic drift is a common feature such discussions, as are a digressions. If the discussion can split off into tangents that have nothing to do with the stated topic, then surely a digression that directly addresses the topic isn’t out of order.
In this case the topic was related to Cecil’s column http://www.straightdope.com/classics/a3_355.html where he dismisses human biomass as part of the equation but does consider infall from space. My contribution was to point out that there is a significant amount of mass lost to outfall of gasses from the upper atmosphere, a fact that Cecil ignores in his column. I doubt that makes any difference in his conclusion since I doubt outfall losses are even of the same order of magnitude as infall gains… but I don’t know.
My apologies of my posting on topic upset the flow of discussion.
Have you thanked a legitimate businessman lately?
Cecil did not ignore that fact in his column. He stated very concisely, (infall from space) “far exceeds any losses.” I would venture to say Unca Cece considered outgassing along with the 36 Hasselblad cameras and untold bags of poop those clowns left on the moon.
Yep, he did. That’s good enough for me. 
Have you thanked a legitimate businessman lately?
Damn it Mark, your making this difficult.
The reason the question was posed in the title and not answered is because this entire thread is a follow up to Cecils column in which he completely and accurately answered that question. This is intended as a discussion of your “digression” as you called it. And since that was the goal it doesn’t really qualify as a digression.
The reason i critcised you is because you are trying to answer a different question than we are and in turn discounting facts we state. We fully realize that these issues don’t relate to the mass of the earth, but thats not the question at hand.
The facts expressed here belong to everybody, the opinions to me. The distinction is
yours to draw…
Omniscient; BAG
IN response to Omniscient’s rebuttal to my points:
Well, I’m not able to find some of the backup material that I seek, and in other places I used words fuzzily. Lemme see if I can rectify the situation.
First, in regards to petroleum not being biomass: I don’t think you understood the point I was making. True, biomass is (according to my ecological soil chemistry text from college) “the total mass of living material of a specified type . . . in a given environment,” and by that definition, petroleum isn’t biomass. That’s not really relevant to my point, however, which was that if we consider petroleum to be under the surface of the earth, then the transfer of mass from biomass on the earth’s outside to petroleummass on the inside makes the earth heavier (assuming we only weigh the insides, which is what this thread is about).
As for the greater biomass in grasslands than in rainforests – during my Ecological Agriculture class last year, this was one of the factoids a prof used to get our attention. I can’t find the supporting evidence, but think about his: the process of agriculture is the removal of organic compounds (a more accurate term, since it includes former biomass that’s now dead) from a patch of land. You with me? You grows your corn, you harvests your corn, you takes it somewhere else. Now. If you practice “slash and burn” agriculture on a rainforest, you get productive land for about five years, after which point you have a patch of useless desert. If you use fire to burn a patch of grassland, you get a patch of agricultural land that is productive for several centuries (viz. the Central US). This is because grasslands can contain several meters of organic soil, as opposed to the centimeters that rainforests have. Most of the organic material in a prairie is below the ground: it accumulates over centuries, whereas in a rainforest, nutrients are snatched up almost as soon as they fall. Again, I don’t intend this to be a proof; I’m unable to find my notes that have supporting evidence. It’s just something to think about. And it only figured in my original point as a factoid related to a question: does eroding soil squelch life in estuaries and in the ocean shallows? I don’t know.
I think you are confusing the greenhouse effect with the hole in the ozone layer. There is some small overlap between the problems, both in their causes and in their effects, but they are distinct issues, and the phytoplankton problem is specifically an ozone hole issue. If you’re unclear why I brought it up, please reread: phytoplankton make up a significant amount of the ocean’s biomass, and if there are significant phytoplankton die-offs, the earth’s biomass will probably decrease. Such a die-off will have implications for the greenhouse effect, but those implications are immaterial to my point.
Incidentally, as for the greenhouse effect’s being a losing argument, please help me out: show me one respected scientific body that isn’t funded by the petroleum industry that denies that the Greenhouse Effect is currently taking place. The National Academy of Sciences, NASA, NOAA, and every other scientific body I could find in a recent Internet search either didn’t mention the Greenhouse Effect or had articles talking about it as a foregone conclusion. After literally thousands of studies, it’s not a losing argument in the scientific community anymore; it’s not even an argument.
Oh! You may have thought that my last point, regarding the burning of rainforests, was addressing the greenhouse effect. Again, it’s a related issue, but the validity of the greenhouse effect is irrelevant to my point. If the earth is losing biomass through the burning of rainforests (which is certainly is, unless you consider smoke to be alive), the question is simply whether the los is temproary or permanent. If other organisms – phytoplankton, other rainforests, or other vegetation – are converting that smoke back into biomass, then the loss is temporary, and we shouldn’t consider it. If the phytoplankton has a fatal case of sunburn, however, and if the rainforests have a fatal case of slash&burn, however, there may not be sufficient vegetation to make the conversion back into biomass. That was my point. The effects of that CO2 on the greenhouse effect weren’t factored in.
I hope this clarifies what I was trying to say. I would appreciate your not calling my points “muddled” unless you can express your understanding of them more clearly.
Regards,
Daniel Withrow
So if the earth gains between 10,000 and 100,000 tons of weight every year from space junk falling to earth we are slowly but surely gaining weight.
So given the fact that the more mass an object has the more gravity it exerts,
1.) How much is gravity increasing on earth as time passes?
2.) Are we humans getting stronger to compensate?
3.) How long will it be before humans will not be able to live on earth because our bodies will not be able to take the excessive gravity
More importantly, would I be able to hop in a time machine, travel back to ancient Egypt and impress all the girls by bench-pressing a 900 lb. pyramid stone.