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Can nuclear weapons destroy the world?

  1. Aug 12, 2018 #1
    Hi guys,

    we have all heard that the world has enough nuclear weapons do destroy the human kind. But is this true?
    I made a small research on wikipedia and it mentions:
    https://en.wikipedia.org/wiki/List_of_states_with_nuclear_weapons
    the total available nuclear warheads in the world are at the most 14800
    will take an worst case scenario and and assume that all of them have a yield of 1Mt (in reality most of them are bellow 500kt)
    https://en.wikipedia.org/wiki/Effects_of_nuclear_explosions
    mentions that 1Mt will cause second degree burns to a radius of 15km (second degree burns are usually not leathal). So 1Mt will destroy 706km2 and
    14800 x 706 = 10456200 km2
    this is approximately the area of Europe and definitely not the area of the whole world.

    Can you please let me know if anything in my logic is wrong?

    Thank you
     
  2. jcsd
  3. Aug 12, 2018 #2

    .Scott

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    There are other effects.
    In particular, nuclear detonations will start firestorms and carry tons of soot and dust into the atmosphere.
    That would reduce the amount of sunlight reaching the ground - perhaps enough to ruin crops.
    https://en.wikipedia.org/wiki/Nuclear_winter
     
  4. Aug 12, 2018 #3
    In addition, loss of electrical power, loss of petroleum, loss of manufacturing capability, loss of transportation systems, loss of fertilizer, etc. Think loss of over half the world's population and a preindustrial economy. It would take some years to get there, during which time we would be depleting the remaining industrial capital. If enough people died soon enough, we might only regress to a horse, blacksmith, and steam economy.

    I may sound pessimistic, but look inside your local grocery store in the morning, then again in the evening. Then ask yourself where next week's food is coming from when we run out of diesel for farm equipment, locomotives, and trucks. Consider that a city of 1,000,000 people needs 1000 tons per day of food.
     
  5. Aug 12, 2018 #4

    jim hardy

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  6. Aug 13, 2018 #5
    #jim hardy
    today's nuclear weapons are mostly hydrogen bombs due to higher yields. There will not be any nuclear fallout from a hydrogen bomb.

    #jrmichler
    No one disagrees that will be a huge disaster and the world will fall some years behind. But this will not be the end of the world. Humans will bounce back relatively quickly.
     
  7. Aug 13, 2018 #6
    When that phrase was invented big fat three phase bombs were the expectation and some sickos were just started to consider using cobalt to 'salt' some bombs.
    Also there was far more of those devices than today.

    For now, I think we have enough (which are small/clean enough) to send back the survivors to the middle ages.
     
    Last edited: Aug 13, 2018
  8. Aug 13, 2018 #7

    mfb

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    Hydrogen bombs use a fission bomb for ignition, and often most of the yield comes from a third fission stage or from combined fission/fusion. Per yield fusion bombs have a smaller fallout than fission bombs, but they are not clean by any means.
    Where is your evidence for that claim?
     
  9. Aug 13, 2018 #8

    jim hardy

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    that's plain wrong.

     
    Last edited: Aug 13, 2018
  10. Aug 13, 2018 #9
    #mfb
    This is my logical assumption. What I can prove is that the world will not be leveled out with the nuclear weapons that are available.

    #jim hardy
    I correct that with :"there will not be a significant nuclear fallout from a hydrogen bomb"

    I'm just trying to prove that the world will not come to an end
     
  11. Aug 13, 2018 #10

    berkeman

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    Quick tip for you, @peterlars -- use the "@" symbol to tag other users, not the "#" symbol. If you type @ and start typing the user's name, you will see a pop-up window with their username which you can click on to finish filling out the tagged username. :smile:
     
  12. Aug 13, 2018 #11
    Wiki is not necessarily the definitive reference (YMMV)...
    https://en.wikipedia.org/wiki/Nuclear_winter
    ... but combining such massive stratospheric injection with circumstantial evidence from mass extinctions triggered by toxic out-gassing from Large Igneous Provinces (LIPs) such as Siberian and Deccan Traps, the dysergic effects are seriously scary.

    There may be a loophole: IIRC, when there is sufficient coastline to allow weathering to reach and cleanse the continental interior, oxygenate the oceans etc, LIPs have much less effect. The N & S Atlantics' opening, the Ontong Java plateau etc seem to have had scant effect on extinction rates.

    That said, a major nuclear exchange would probably throw most survivors back to 'Feudal' or beyond...
    Be Not There.
     
  13. Aug 13, 2018 #12

    jim hardy

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  14. Aug 13, 2018 #13

    jim mcnamara

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    @peterlars we are still waiting for a scientific citation for this claim:
    Please provide one.
     
  15. Aug 13, 2018 #14
    @jim mcnamara my question is if the nuclear war can destroy the world.
    The question was made to see if there are any mistakes in my logic.
    If my calculations are correct earth will not be level out (please keep in mind that my calculation are an overestimation). I didn't take into account the proposed nuclear winter and nuclear fallout. I have corrected the "There will not be any nuclear fallout from a hydrogen bomb." with "there will not be a significant nuclear fallout from a hydrogen bomb". @jim hardy has provided more information of accidental nuclear fallout from a hydrogen bomb but this was an isolated example. Please provide more info for a nuclear fallout from a hydrogen bomb if you have and will be happy to accept that.
     
    Last edited: Aug 13, 2018
  16. Aug 13, 2018 #15

    Bystander

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    "Politically, or 'Star Wars-ly?' "
     
  17. Aug 13, 2018 #16

    mfb

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    @peterlars: This is not how the forum works. You can't just make up claims and, when shown to be wrong, modify them a bit to still fit your narrative, and then wait to be shown wrong again.
    If you make a claim, back it by references - the latest when asked for them. If the claim is not backed by the scientific literature, do not make it.
    While that is correct: No one claimed otherwise. The dangers of a global nuclear war are not from leveling everything.
     
  18. Aug 13, 2018 #17
    @mfb my question is if a nuclear war can destroy the world. I'm not convinced that it will. Please see the forest here not the tree.
    @Bystander I mean Star wars-ly.
     
  19. Aug 13, 2018 #18

    berkeman

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    Then the answer is clearly No. Thread is done.
     
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