# Total Mass: Atoms & Human Population? **URL:** \ **Category:** Factual Questions\ **Created:** [November 5, 2012, 5:34am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929 "2012-11-05T05:34:47Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [November 5, 2012, 5:34am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/1 "2012-11-05T05:34:47Z")
Do we know how many carbon atoms are on earth? Or, can estimates from known mass of the earth, percent composition for each elements, etc., be calculated? And, if so…would conservation of mass eventually limit the human population esp. as we live longer and longer lives? (Perhaps some extrapolation to human population figures may be necessary here?) One day, could we face a carbon shortage on earth??? ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 5, 2012, 5:39am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/2 "2012-11-05T05:39:47Z")
We’d run out of food before we need to worry about a carbon shortage, because food is made of the same stuff we are. Then we’d all die. And get eaten by something. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [November 5, 2012, 5:40am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/3 "2012-11-05T05:40:26Z")
All living matter has carbon in it. Even if every human became a vegan, and there were no other animals on earth, we’d need an enormous amount of plant matter to produce all the oxygen for us to breathe. In addition, carbon is not the bottleneck element. Isaac Asimov had a column on this back in the day when he wrote monthly columns for Analog. I think phosphorous was the element that was the one that was most overrepresented in living matter compared to its abundance. I’ll try to see if I can find a cite. Here’s one: [Encyclopedia Asimova: "Life's Bottleneck," part 2](http://encyclopediaasimova.blogspot.com/2011/03/lifes-bottleneck-part-2.html) ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [November 5, 2012, 5:42am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/4 "2012-11-05T05:42:10Z")
> [@](#): > > Carbon is the [fourth most abundant chemical element](https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements) in the universe by mass after hydrogen, helium, and oxygen. Carbon is abundant in the [Sun](https://en.wikipedia.org/wiki/Sun), [stars](https://en.wikipedia.org/wiki/Star), [comets](https://en.wikipedia.org/wiki/Comet), and in the [atmospheres](https://en.wikipedia.org/wiki/Celestial_body%27s_atmosphere) of most [planets](https://en.wikipedia.org/wiki/Planet). Some [meteorites](https://en.wikipedia.org/wiki/Meteorite) contain microscopic diamonds that were formed when the [solar system](https://en.wikipedia.org/wiki/Solar_system) was still a [protoplanetary disk](https://en.wikipedia.org/wiki/Protoplanetary_disk). Microscopic diamonds may also be formed by the intense pressure and high temperature at the sites of meteorite impacts.[[39]](https://en.wikipedia.org/wiki/Carbon#cite_note-38) > In combination with [oxygen](https://en.wikipedia.org/wiki/Oxygen) in [carbon dioxide](https://en.wikipedia.org/wiki/Carbon_dioxide), carbon is found in the Earth’s atmosphere (approximately 810 [gigatonnes](https://en.wikipedia.org/wiki/Gigatonne) of carbon) and dissolved in all water bodies (approximately 36,000 gigatonnes of carbon). Around 1,900 gigatonnes of carbon are present in the [biosphere](https://en.wikipedia.org/wiki/Biosphere). [Hydrocarbons](https://en.wikipedia.org/wiki/Hydrocarbons) (such as [coal](https://en.wikipedia.org/wiki/Coal), [petroleum](https://en.wikipedia.org/wiki/Petroleum), and [natural gas](https://en.wikipedia.org/wiki/Natural_gas)) contain carbon as well—[coal](https://en.wikipedia.org/wiki/Coal) [“reserves” (not “resources”)](https://en.wikipedia.org/wiki/Mineral_resource_classification) amount to around 900 gigatonnes, and [oil reserves](https://en.wikipedia.org/wiki/Oil_reserves) around 150 gigatonnes. Proven sources of natural gas are about 175 1012 cubic metres (representing about 105 gigatonnes carbon), but it is estimated that there are also about 900 1012 cubic metres of “unconventional” gas such as [shale gas](https://en.wikipedia.org/wiki/Shale_gas), representing about 540 gigatonnes of carbon.[[40]](https://en.wikipedia.org/wiki/Carbon#cite_note-39) (In the past, quantities of hydrocarbons were greater. In the period from 1751 to 2008 about 347 gigatonnes of carbon were released as carbon dioxide to the atmosphere from burning of fossil fuels.[[41]](https://en.wikipedia.org/wiki/Carbon#cite_note-40)) Carbon is also locked up as [methane](https://en.wikipedia.org/wiki/Methane) and [methane hydrates](https://en.wikipedia.org/wiki/Methane_hydrates) in polar regions. It is estimated that at least 1,400 [Gt](https://en.wikipedia.org/wiki/Gigatonne) of carbon is in this form just in (and under) the submarine [permafrost](https://en.wikipedia.org/wiki/Permafrost) of the [Siberian Shelf](https://en.wikipedia.org/wiki/Siberian_Shelf).[[42]](https://en.wikipedia.org/wiki/Carbon#cite_note-41) > Carbon is a major component in very large masses of [carbonate](https://en.wikipedia.org/wiki/Carbonate) rock ([limestone](https://en.wikipedia.org/wiki/Limestone), [dolomite](https://en.wikipedia.org/wiki/Dolomite), [marble](https://en.wikipedia.org/wiki/Marble) and so on). [Coal](https://en.wikipedia.org/wiki/Coal) is the largest commercial source of mineral carbon, accounting for 4,000 gigatonnes or 80% of fossil carbon fuel.[[43]](https://en.wikipedia.org/wiki/Carbon#cite_note-42) It is also rich in carbon – for example, [anthracite](https://en.wikipedia.org/wiki/Anthracite) contains 92–98%.[[44]](https://en.wikipedia.org/wiki/Carbon#cite_note-43) > As for individual carbon allotropes, graphite is found in large quantities in the [United States](https://en.wikipedia.org/wiki/United_States) (mostly in [New York](https://en.wikipedia.org/wiki/New_York) and [Texas](https://en.wikipedia.org/wiki/Texas)), [Russia](https://en.wikipedia.org/wiki/Russia), [Mexico](https://en.wikipedia.org/wiki/Mexico), [Greenland](https://en.wikipedia.org/wiki/Greenland), and [India](https://en.wikipedia.org/wiki/India). Natural diamonds occur in the rock [kimberlite](https://en.wikipedia.org/wiki/Kimberlite), found in ancient [volcanic](https://en.wikipedia.org/wiki/Volcano) “necks”, or “pipes”. Most diamond deposits are in [Africa](https://en.wikipedia.org/wiki/Africa), notably in [South Africa](https://en.wikipedia.org/wiki/South_Africa), [Namibia](https://en.wikipedia.org/wiki/Namibia), [Botswana](https://en.wikipedia.org/wiki/Botswana), the [Republic of the Congo](https://en.wikipedia.org/wiki/Republic_of_the_Congo), and [Sierra Leone](https://en.wikipedia.org/wiki/Sierra_Leone). There are also deposits in [Arkansas](https://en.wikipedia.org/wiki/Arkansas), [Canada](https://en.wikipedia.org/wiki/Canada), the Russian [Arctic](https://en.wikipedia.org/wiki/Arctic), [Brazil](https://en.wikipedia.org/wiki/Brazil) and in Northern and Western [Australia](https://en.wikipedia.org/wiki/Australia). Diamonds are now also being recovered from the ocean floor off the [Cape of Good Hope](https://en.wikipedia.org/wiki/Cape_of_Good_Hope). However, though diamonds are found naturally, about 30% of all industrial diamonds used in the U.S. are now made synthetically. [Carbon - Wikipedia](https://en.wikipedia.org/wiki/Carbon) ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [November 5, 2012, 5:43am UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/5 "2012-11-05T05:43:51Z")
OldGuy, that’d be great if you could find a cite! “Isaac Asimov had a column on this back in the day when he wrote monthly columns for Analog. I think phosphorous was the element that was the one that was most overrepresented in living matter compared to its abundance.” See? I’m not crazy! Well…that’s a matter for Great Debates! 😉 ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [November 5, 2012, 3:53pm UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/6 "2012-11-05T15:53:02Z")
> [@OldGuy](#): > > Isaac Asimov had a column on this back in the day when he wrote monthly columns for Analog. Actually, the monthly columns were for The Magazine of Fantasy and Science Fiction. That one was “Life’s Bottleneck” in the April, 1959 issue. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [November 5, 2012, 4:05pm UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/7 "2012-11-05T16:05:16Z")
> [@Exapno\_Mapcase](#): > > Actually, the monthly columns were for The Magazine of Fantasy and Science Fiction. That one was “Life’s Bottleneck” in the April, 1959 issue. Thanks for the correction. Also this essay was reprinted in one of his books that reprinted the columns – probably Fact and Fancy since I recall it so well and that was the one I owned as a child. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [November 5, 2012, 5:02pm UTC](https://boards.straightdope.com/t/total-mass-atoms-human-population/639929/8 "2012-11-05T17:02:14Z")
> [@OldGuy](#): > > Thanks for the correction. Also this essay was reprinted in one of his books that reprinted the columns – probably Fact and Fancy since I recall it so well and that was the one I owned as a child. Yep, _Fact and Fancy_. The only reprint that I can find. Asimov did 399 monthly columns for _F&SF_, dying just before he could churn out the magic #400 which I’m sure pissed him no end, if he knew. They’re mostly all reprinted, but the very first one, “Dust of Ages” in the November 1958 _F&SF_, never has been that I know of. He did do a few essays before that for _Astounding Science Fiction_. That was several years before it changed its name to _Analog Science Fiction/Science Fact_, though. He wasn’t getting along well with John W. Campbell by that time and so he was happy to switch to the much more congenial people at _F&SF_. I think he was proudest of those essays of all his nonfiction work. More than you needed, but I grew up on these.