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Ukraine Open Thread 2023-60
Only for news & views directly related to the Ukraine conflict.
The current open thread for other issues is here.
Please stick to the topic. Contribute facts. Do not attack other commentators.
@FieryButMostPeaceful | Mar 12 2023 20:02 utc | 108
@Mike R | Mar 12 2023 21:20 utc | 128
@irish al | Mar 12 2023 17:44 utc | 56
@Mike R | Mar 12 2023 23:35 utc | 158
Humans produce some 10,042 terawatt hours from coal each year. Given approximately 0.404 kg coal.kWh^-1 that implies burning 4.056968 Eg of coal per year, resulting in about 20 Eg of invisible CO2 being added to the atmosphere each year (other fuels produce another 15 Eg). However, all power stations are designed to burn their fuels in a neutral to oxidizing environment to ensure complete combustion and have scrubbers and filters on their exhausts (to eliminate particulate matter and to reduce sulfur and other emissions). Waste heat is used to heat feed water in order to increase efficiency, and this means that their exhausts tend to be at temperatures near 100C (the lower the exhaust temperature the higher the plants thermal efficiency). So you have high global warming potential, from the coal which releases methanes and employs huge amounts of legacy carbon in it’s supply chain, through CO2 to the enormous volumes of waste heat produced in the production and employment of electricity. However, there is little soot produced and little if any makes it 8nto the stratosphere.
Thermonuclear warfare is not the same thing at all. Assuming the targeting of a city of 5 million people, the people themselves, though comprising some 18500 g of carbon per 100kg human would make up a miniscule contribution to the total, with buildings and possessions at about 30,000 kg of carbon per person, or 30 Mg per person or some 150 Tg per city, comprising the major proportion of carbon supply. As the vast majority of this carbon would be vaporized (into carbon gas) rather than burned (combined with oxygen to form carbon monoxide, carbon dioxide or more complex compounds), it will condense out as soot as the product cools. Just as significantly, rather than 80 to 120 C of power station emissions, temperatures within a thermonuclear fireball reach 100 million Celsius (about the same temperature as the interior of the sun) within milliseconds, expanding and heating the air, reducing its density at a rate approximating to the ideal gas law of pV = nRT with the density decreasing by about 1% for every increase in temperature of 3C. This, together with air rushing in, results in an uplift, taking soot, dust and other products of the thermonuclear detonations directly into the stratosphere, where it never rains. There it will cool and precipitate out into dust particles that will remain in the stratosphere for decades, 9ccluding the sun and cooling the planet.
This is not a purely theoretical model. The experiment has been performed repeatedly. Perhaps the best illustration is the Permian-Triassic extinction event (End Permian) at c 252 MYBP, at the Permian-Triassic transition. This event, which combined comets and volcanoes causing widespread fires that injected dust and soot into the stratosphere, resulting in the decadal blocking of sunlight with a consequent reduction of photosynthesis which killed 57% of all families, 83% of all genera and 90% to 96% of all species (53% of marine families, 84% of marine genera, about 81% of all marine species and an estimated 70% of land species, including insects). Oxygen, which is a highly reactive gas, continuously replenished by photosynthesis since about 850 MYBP plummeted.
Were this to happen today as a result of thermonuclear activity, the impact would be similar, and there is no way that the keystone species, which always depend on the health of the entire underlying ecosystem, in current times humans and their livestock which makes up about 97% of all terrestrial mammals, could possibly survive, any more than trilobites, the keystone species of the late Devonian, survived those extinction events.
The impacts on temperature and photosynthesis of thermonuclear war at various scales have been modelled, and would result in human extinction at levels of a few hundred medium sized detonations over cities. On a planet with some 18,000 known Devices, and pits for perhaps another 50,000 that could be assembled in days or weeks, the only hope of avoiding an extinction event is to avoid a thermonuclear war.
See e.g. my monograph, Wars of Depopulation and associated footnotes.
Posted by: Hermit | Mar 13 2023 21:47 utc | 305
@FieryButMostPeaceful | Mar 15 2023 11:19 utc | 323
Those combustible things in the vicinity of a detonation that are not vaporized are burned and when there is fuel available to establish a fireball the resulting burn area exceeds even the light blast radius, because, as we saw in e.g. London’s Great Fire, the Chicago Fire, and the aforementioned Tokyo and Dresden fireballs, the heat of an urban fireball creates an expanding combustion area. For example, a US W80 with a 150 ktonne TNT equivalent explosion detonated at 1660m to optimize the 5km blast damage would be expected to vaporize 0.5 km² and incinerate everything flammable in an area of about 200 to 300 km^2. A 100 Mtonne detonation would be expected to vaporize around 120 km² and incinerate some 25,000 to 30,000 km². More than enough to result in the effects I mentioned.
The difference between an ordinary fire and a firestorm is heat which determines the products released into the atmosphere where they force warming, and the stratosphere, where they cause cooling. A sufficient level of heat injects products of combustion into the stratosphere. Nuclear detonations differ from fires in that all nuclear detonations release sufficient heat to ensure stratospheric injection.
I recommend Charles G. Bardeen, Douglas E. Kinnison, Owen B. Toon, Michael J. Mills, Francis Vitt, Lili Xia, Jonas Jägermeyr, Nicole S. Lovenduski, Kim J. N. Scherrer, Margot Clyne, Alan Robock (2021-09-10). Extreme Ozone Loss Following Nuclear War Results in Enhanced Surface Ultraviolet Radiation. Journal of Geophysical Research: Atmospheres. Volume 126, Issue 18 e2021JD035079. “>https://doi.org/10.1029/2021JD035079 to your attention.
From that we can see that “In this study, two types of wars are simulated: a regional nuclear war between India and Pakistan, and a global nuclear war between the United States and Russia. The regional war follows the 5 Tg of soot scenario described in Toon et al. (2019) using 44 15 kt-weapons with urban targets in a war lasting 3 days and is similar to that used by Mills et al. (2008, 2014). Smoke is emitted instantaneously when a target is attacked.
The global war follows Coupe et al. (2019) and is similar to that used by Robock, Oman, and Stenchikov (2007). It assumes that 150 Tg of soot is emitted uniformly over the continental US and Russia. The war lasts 7 days and the smoke emissions ramp down linearly during that time. As was done in previous studies, these wars are assumed to start on May 15th of the first year. Coupe et al. (2019) and Robock, Oman, and Stenchikov (2007) did not include weapon counts or yields needed for determining NOx emissions, so we have performed sensitivity tests with weapons inventories from: Toon et al. (2008), Kristensen and Korda (2020a, 2020b), and NRC (1985).”
…
” Plain Language Summary
Nuclear war would result in many immediate fatalities from the blast, heat, and radiation, but smoke from fires started by these weapons could also cause climate change lasting up to 15 years threatening food production. For the first time with a modern climate model, we have simulated the effects on ozone chemistry and surface ultraviolet (UV) light caused by absorption of sunlight by smoke from a global nuclear war. This could lead to a loss of most of our protective ozone layer taking a decade to recover and resulting in several years of extremely high UV light at the surface further endangering human health and food supplies.”
The earth is already a stressed biosphere, in the midst of the worst extinction event in it’s history (measured by known species loss per year) and approaching many tipping points. Which is why few existing species are likely to survive even a relatively small regional war involving limited numbers of atmospheric deployment of thermonuclear devices. No keystone species, which are uniquely dependent on the health of the entire 7nderlying ecosystem, has been known to survive such an extinction event.We have no reason to imagine that humans would be an exception.
Maybe you could try to restrain projecting your Dunning-Kruger with added obnoxiousness and try to recognize that scientists who understand and model such events, and risk managers who analyze the potential impact, might know more than you about their subjects.
Posted by: Hermit | Mar 15 2023 17:26 utc | 324
Your inability to differentiate between local and global, let alone between the atmosphere and the stratosphere precludes meaningful discussion on this issue
The math illiterate clearly can’t read numbers.
I’ll paste my comment one more time, though I still don’t think you’ll get it.
From that we can see that “In this study, two types of wars are simulated: a regional nuclear war between India and Pakistan, and a global nuclear war between the United States and Russia. The regional war follows the 5 Tg of soot scenario described in Toon et al. (2019) using 44 15 kt-weapons with urban targets in a war lasting 3 days and is similar to that used by Mills et al. (2008, 2014). Smoke is emitted instantaneously when a target is attacked.
The global war follows Coupe et al. (2019) and is similar to that used by Robock, Oman, and Stenchikov (2007). It assumes that 150 Tg of soot is emitted uniformly over the continental US and Russia. The war lasts 7 days and the smoke emissions ramp down linearly during that time. As was done in previous studies, these wars are assumed to start on May 15th of the first year. Coupe et al. (2019) and Robock, Oman, and Stenchikov (2007) did not include weapon counts or yields needed for determining NOx emissions, so we have performed sensitivity tests with weapons inventories from: Toon et al. (2008), Kristensen and Korda (2020a, 2020b), and NRC (1985).”
8Tg of soot emitted into atmosphere annually which is 5% of total anthropogenically produced aerosol
That’s 5% aerosol which is about 160 Tg. PER YEAR.
“Local or global” doesn’t matter when the net quantity is the same. In fact, if it’s “global”, I.e. spread across the global the effect is minimized.
I have to ask you even read your own citations or do you just not undertand numbers?
The ozone crisis was ameliorated by a concerted and very expensive global effort. If we had not addressed it, we would be in an unprecedented UV crisis as well as the myriad other existential threats we have created.
Once again, ozone spontaneously replenishes itself. Once the source of the depletion is gone i.e. bombs are done exploding, it eventually recovers . Plus, none of your citations predict human extinction. If only you read the stuff you post.
You don’t seem to know very much about nuclear weapons either. There is no theoretical limit to the size of a high-yield thermonuclear device. For example, the Tsar Bomba of 1961 was designed to yield some 420PJ (100 Mtonnes TNT equivalent). When tested, in order to limit fallout, they removed the uranium-238 fusion tamper. Even without this, the yield exceeded 250 PJ (over 50 Mtonne equivalent).
Ok, mister I-can-solve-multi-particle-nuclear-hamiltonian-expert-in-all-things-nuclear point to the country which has 100+ megaton war head deployed in strategic ICBMs and ready to go.
If not, I recommend “simulating” this million Tsar Bomba war in your imagination with the internet turned off because some of us live in the real world.
You appear to be basking in misplaced pride, while mistaking stupidity for common sense, ignorance for education and belligerence for wit. In Russian there is a lovely word that encapsulates this kind of pig-ignorance, некультурный (nekulturny uncivilized) which English lacks, but which appears to apply. Which part of the Southern USA do you call home? If you exemplify it, I want to be sure to avoid it.
Once again, quite a mouth for a math-illterate.
I’ll leave you to it.
Posted by: FieryButMostPeaceful | Mar 17 2023 17:11 utc | 328
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