Total Mass: Atoms & Human Population?

[Jinx]

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???

[friedo]

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.

[OldGuy]

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

[Duckster]

Carbon is the fourth most abundant chemical element in the universe by mass after hydrogen, helium, and oxygen. Carbon is abundant in the Sun, stars, comets, and in the atmospheres of most planets. Some meteorites contain microscopic diamonds that were formed when the solar system was still a protoplanetary disk. Microscopic diamonds may also be formed by the intense pressure and high temperature at the sites of meteorite impacts.[39]
In combination with oxygen in carbon dioxide, carbon is found in the Earth’s atmosphere (approximately 810 gigatonnes 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. Hydrocarbons (such as coal, petroleum, and natural gas) contain carbon as well—coal “reserves” (not “resources”) amount to around 900 gigatonnes, and 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, representing about 540 gigatonnes of carbon.[40] (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]) Carbon is also locked up as methane and methane hydrates in polar regions. It is estimated that at least 1,400 Gt of carbon is in this form just in (and under) the submarine permafrost of the Siberian Shelf.[42]
Carbon is a major component in very large masses of carbonate rock (limestone, dolomite, marble and so on). Coal is the largest commercial source of mineral carbon, accounting for 4,000 gigatonnes or 80% of fossil carbon fuel.[43] It is also rich in carbon – for example, anthracite contains 92–98%.[44]
As for individual carbon allotropes, graphite is found in large quantities in the United States (mostly in New York and Texas), Russia, Mexico, Greenland, and India. Natural diamonds occur in the rock kimberlite, found in ancient volcanic “necks”, or “pipes”. Most diamond deposits are in Africa, notably in South Africa, Namibia, Botswana, the Republic of the Congo, and Sierra Leone. There are also deposits in Arkansas, Canada, the Russian Arctic, Brazil and in Northern and Western Australia. Diamonds are now also being recovered from the ocean floor off the 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

[Jinx]

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!

[Exapno_Mapcase]

@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.

[OldGuy]

@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.

[Exapno_Mapcase]

@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.