Editing Nuclear winter (section)

=== Early work ===
[[File:Nukecloud.png|thumb|upright=2|The mushroom cloud height as a function of [[TNT equivalent|explosive yield]] detonated as [[surface burst]]s.<ref name="Figure 1">{{cite magazine |author=Martin |first=Brian |date=December 1982 |title=The global health effects of nuclear war |url=http://www.bmartin.cc/pubs/82cab/ |url-status=live |magazine=Current Affairs Bulletin |volume=59 |issue=7 |pages=14–26 |archive-url=https://web.archive.org/web/20141006093303/http://www.bmartin.cc/pubs/82cab/ |archive-date=2014-10-06 |access-date=2014-10-03 |via=www.bmartin.cc}}</ref>{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions|1985 |loc="Chapter: 4 Dust" pp. 20–21, figure 4.2 & 4.3}} As charted, yields at least in the megaton range are required to lift dust/[[fallout]] into the stratosphere. Ozone reaches its maximum concentration at about 25 km (c. 82,000 ft) in altitude.<ref name="Figure 1"/> Another means of stratospheric entry is from [[High-altitude nuclear explosion|high altitude nuclear detonations]], one example of which includes the 10.5 kiloton Soviet ''test [[1961 Soviet nuclear tests|no.#88]]'' of 1961, detonated at 22.7 km.<ref>{{cite web |url=http://www.futurescience.com/emp/test184.html|title=Electromagnetic Pulse - Soviet Test 184 - EMP |website=www.futurescience.com|access-date=2015-07-20|url-status=live|archive-url=https://web.archive.org/web/20150718124742/http://www.futurescience.com/emp/test184.html|archive-date=2015-07-18}}</ref><ref>{{cite web |url=http://www.iss-atom.ru/sssr2/1_9.htm|archive-url=https://web.archive.org/web/20140406175913/http://www.iss-atom.ru/sssr2/1_9.htm|archive-date=6 April 2014|title=ЯДЕРНЫЕ ИСПЫТАНИЯ В СССР, ТОМ II, глава 1|date=6 April 2014}}</ref> US high-yield upper atmospheric tests, ''Teak'' and ''Orange'' were also assessed for their ozone destruction potential.<ref>{{cite web |url=https://www.fas.org/sgp/othergov/doe/lanl/docs1/00322994.pdf|title=United States High-Altitude Test Experiences – A Review Emphasizing the Impact on the Environment 1976. Herman Hoerlin. LASL |access-date=2016-10-28|archive-url=https://web.archive.org/web/20161006125252/https://fas.org/sgp/othergov/doe/lanl/docs1/00322994.pdf |archive-date=2016-10-06|url-status=live}}</ref><ref>{{cite journal|title=Review of Nuclear Weapons Effects |journal=[[Annual Review of Nuclear Science]] |volume=18 |pages=153–202 |year=1968 |last1=Brode |first1=H. L. |bibcode=1968ARNPS..18..153B|doi=10.1146/annurev.ns.18.120168.001101}}</ref><br /> 0 = Approx altitude commercial aircraft operate<br />1 = [[Fat Man]]<br />2 = [[Castle Bravo]]]]

In 1952, a few weeks prior to the [[Ivy Mike]] (10.4 [[Megatons|megaton]]) bomb test on [[Elugelab]] Island, there were concerns that the aerosols lifted by the explosion might cool the Earth. Major Norair Lulejian, [[USAF]], and astronomer Natarajan Visvanathan studied this possibility, reporting their findings in ''Effects of Superweapons Upon the Climate of the World'', the distribution of which was tightly controlled. This report is described in a 2013 report by the [[Defense Threat Reduction Agency]] as the initial study of the "nuclear winter" concept. It indicated no appreciable chance of explosion-induced climate change.<ref>{{cite Q|Q63070323}}</ref>

The implications for civil defense of numerous surface bursts of high yield [[hydrogen bomb]] explosions on [[Pacific Proving Ground]] islands such as those of Ivy Mike in 1952 and Castle Bravo (15 Mt) in 1954 were described in a 1957 report on ''The Effects of Nuclear Weapons'', edited by [[Samuel Glasstone]]. A section in that book entitled "Nuclear Bombs and the Weather" states: "The dust raised in severe [[volcanic eruptions]], such as that at [[1883 eruption of Krakatoa|Krakatoa]] in 1883, is known to cause a noticeable reduction in the sunlight reaching the earth ... The amount of [soil or other surface] debris remaining in the atmosphere after the explosion of even the largest nuclear weapons is probably not more than about one percent or so of that raised by the Krakatoa eruption. Further, solar radiation records reveal that none of the nuclear explosions to date has resulted in any detectable change in the direct sunlight recorded on the ground."<ref>[http://babel.hathitrust.org/cgi/pt?seq=9&view=image&size=100&id=mdp.39015010999814&u=1&num=69 The Effects of Nuclear Weapons] {{Webarchive|url=https://web.archive.org/web/20140824081908/http://babel.hathitrust.org/cgi/pt?seq=9&view=image&size=100&id=mdp.39015010999814&u=1&num=69|date=2014-08-24}} Samuel Glasstone, Washington DC, Government Printing Office, 1956, p. 69071. A similar report had been issued in 1950 under a slightly different title: {{cite Q|Q63133275}}. This earlier version seems not to have discussed Krakatoa nor other climate change possibilities.</ref> The US [[Weather Bureau]] in 1956 regarded it as conceivable that a large enough nuclear war with megaton-range surface detonations could lift enough soil to cause a new [[ice age]].<ref>{{cite journal | doi = 10.1086/661272 | pmid=21936194 | volume=26 | title=The Politics of Atmospheric Sciences: "Nuclear Winter" and Global Climate Change | journal=Osiris | pages=198–223 | year=2011 | last1 = Dörries | first1 = Matthias| s2cid=23719340 | url=https://univoak.eu/islandora/object/islandora%3A62598 }}</ref>

The 1966 [[RAND corporation]] memorandum ''The Effects of Nuclear War on the Weather and Climate'' by E. S. Batten, while primarily analysing potential dust effects from surface bursts,{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions|1985|p=185}} notes that "in addition to the effects of the debris, extensive fires ignited by nuclear detonations might change the surface characteristics of the area and modify local weather patterns ... however, a more thorough knowledge of the atmosphere is necessary to determine their exact nature, extent, and magnitude."<ref>{{Cite web |author=Batten |first=E. S. |date=August 1966 |title=The Effects of Nuclear War on the Weather and Climate |url=https://www.rand.org/content/dam/rand/pubs/research_memoranda/2008/RM4989.pdf |url-status=live |archive-url=https://web.archive.org/web/20160304061417/http://www.rand.org/content/dam/rand/pubs/research_memoranda/2008/RM4989.pdf |archive-date=2016-03-04 |access-date=2016-06-04}}</ref>

In the [[United States National Research Council]] (NRC) book ''Long-Term Worldwide Effects of Multiple Nuclear-Weapons Detonations'' published in 1975, it states that a nuclear war involving 4,000 Mt from ''present arsenals'' would probably deposit much less dust in the stratosphere than the Krakatoa eruption, judging that the effect of dust and oxides of nitrogen would probably be slight climatic cooling which "would probably lie within normal global climatic variability, but the possibility of climatic changes of a more dramatic nature cannot be ruled out".<ref name="Figure 1"/>{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions |1985|p={{page needed|date=September 2021}}}}<ref>{{Cite book |author=National Research Council |title=Long-term worldwide effects of multiple nuclear weapons detonations |place=Washington DC |publisher=National Academy of Sciences |page=38 |isbn=978-0-309-02418-1 |year=1975 |access-date=2016-06-04 |url=https://books.google.com/books?id=JVArAAAAYAAJ&q=%22Long-term%20worldwide%20effects%20of%20multiple%20nuclear%20weapons%20detonations%22&pg=PA25}}</ref>

In the 1985 report, ''The Effects on the Atmosphere of a Major Nuclear Exchange'', the Committee on the Atmospheric Effects of Nuclear Explosions argues that a "plausible" estimate on the amount of stratospheric dust injected following a surface burst of 1 Mt is 0.3 teragrams, of which 8 percent would be in the [[Micrometre|micrometer]] range.{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions|1985 |loc="Chapter: 4 Dust" pp. 17–25}} The potential cooling from soil dust was again looked at in 1992, in a US [[National Academy of Sciences]] (NAS)<ref name="Sciences 1992, pp. 433">{{cite book |author=National Academy of Sciences |title=Policy implications of greenhouse warming: Mitigation, adaptation and the science base |publisher=National Academy Press |place=Washington DC |year=1992 |pages=433–464}}</ref> report on [[climate engineering|geoengineering]], which estimated that about 10<sup>10</sup> kg (10 teragrams) of stratospheric injected soil dust with [[particulate matter|particulate grain]] dimensions of 0.1 to 1 micrometer would be required to mitigate the warming from a [[climate sensitivity|doubling of atmospheric]] carbon dioxide, that is, to produce ~2&nbsp;°C of cooling.<ref>{{cite journal |author=Bala |first=G. |date=10 January 2009 |title=Problems with geoengineering schemes to combat climate change |journal=Current Science |volume=96 |issue=1}}</ref>

In 1969, [[Paul Crutzen]] discovered that [[NOx|oxides of nitrogen]] (NOx) could be an efficient catalyst for the destruction of the ozone layer/[[stratospheric ozone]]. Following studies on the potential effects of NOx generated by engine heat in stratosphere flying [[Supersonic Transport]] (SST) airplanes in the 1970s, in 1974, John Hampson suggested in the journal ''[[Nature (journal)|Nature]]'' that due to the creation of atmospheric NOx by [[nuclear fireball]]s, a full-scale nuclear exchange could result in depletion of the ozone shield, possibly subjecting the earth to ultraviolet radiation for a year or more.{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions |1985|p={{page needed|date=September 2021}}}}<ref>{{cite journal |author=Hampson |first=John |date=1974 |title=Photochemical war on the atmosphere |journal=Nature |volume=250 |issue=5463 |pages=189–191 |bibcode=1974Natur.250..189H |doi=10.1038/250189a0 |s2cid=4167666}}</ref> In 1975, Hampson's hypothesis "led directly"<ref name="bmartin.cc1" /> to the [[United States National Research Council]] (NRC) reporting on the models of ozone depletion following nuclear war in the book ''Long-Term Worldwide Effects of Multiple Nuclear-Weapons Detonations''.{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions |1985|p={{page needed|date=September 2021}}}}

In the section of this 1975 NRC book pertaining to the issue of fireball generated NOx and ozone layer loss therefrom, the NRC presented model calculations from the early-to-mid 1970s on the effects of a nuclear war with the use of large numbers of multi-megaton yield detonations, which returned conclusions that this could reduce ozone levels by 50 percent or more in the northern hemisphere.<ref name="Figure 1"/>{{sfn|Committee on the Atmospheric Effects of Nuclear Explosions|1985|p=186}}

However, independent of the computer models presented in the 1975 NRC works, a paper in 1973 in the journal ''[[Nature (journal)|Nature]]'' depicts the stratospheric ozone levels worldwide overlaid upon the number of nuclear detonations during the era of atmospheric testing. The authors conclude that neither the data nor their models show any correlation between the approximate 500 Mt in historical atmospheric testing and an increase or decrease of ozone concentration.<ref name="Goldsmith 1973">{{cite journal |last1=Goldsmith |first1=P. |last2=Tuck|first2=A. F. |last3=Foot|first3=J. S. |last4=Simmons|first4=E. L. |last5=Newson |first5=R. L. |year=1973 |title=Nitrogen Oxides, Nuclear Weapon Testing, Concorde and Stratospheric Ozone |journal=Nature |volume=244 |issue=5418 |pages=545–551 |doi=10.1038/244545a0 |bibcode=1973Natur.244..545G |s2cid=4222122 |url=http://www.uow.edu.au/~bmartin/pubs/79bias/Goldsmith.pdf|access-date=2016-10-26|archive-url=https://web.archive.org/web/20161208052639/http://www.uow.edu.au/~bmartin/pubs/79bias/Goldsmith.pdf |archive-date=2016-12-08 }}</ref> In 1976, a study on the experimental measurements of an earlier atmospheric nuclear test as it affected the ozone layer also found that nuclear detonations are exonerated of depleting ozone, after the at first alarming model calculations of the time.<ref>{{cite journal |last=Christie |first=J. D. |date=1976-05-20 |title=Atmospheric ozone depletion by nuclear weapons testing |journal=Journal of Geophysical Research |volume=81 |issue=15 |pages=2583–2594 |bibcode=1976JGR....81.2583C |doi=10.1029/JC081i015p02583}}</ref> Similarly, a 1981 paper found that the models on ozone destruction from one test and the physical measurements taken were in disagreement, as no destruction was observed.<ref name=":2">{{cite journal |doi=10.1029/JC086iC02p01167 |bibcode=1981JGR....86.1167M |volume=86 |issue=C2 |title=Measurements of nitric oxide after a nuclear burst |journal=Journal of Geophysical Research |page=1167 |year=1981 |last1=McGhan |first1=M.}}</ref>

In total, about 500 Mt were atmospherically detonated between 1945 and 1971,<ref>{{cite book |title=Atmospheric Nuclear Tests|first=O. A.|last=Pavlovski|date=13 September 1998|publisher=Springer Berlin Heidelberg |pages=219–260 |doi=10.1007/978-3-662-03610-5_17|chapter = Radiological Consequences of Nuclear Testing for the Population of the Former USSR (Input Information, Models, Dose, and Risk Estimates) |isbn=978-3-642-08359-4}}</ref> peaking in 1961–1962, when 340 Mt were detonated in the atmosphere by the United States and Soviet Union.<ref>{{cite web|title=Worldwide Effects of Nuclear War – Radioactive Fallout |website=www.atomicarchive.com |url=http://www.atomicarchive.com/Docs/Effects/wenw_chp2.shtml |access-date=2014-10-03|archive-url=https://web.archive.org/web/20141006131515/http://www.atomicarchive.com/Docs/Effects/wenw_chp2.shtml |archive-date=2014-10-06|url-status=live}}</ref> During this peak, with the multi-megaton range detonations of the two nations nuclear test series, in exclusive examination, a total yield estimated at 300 Mt of energy was released. Due to this, 3 × 10<sup>34</sup> additional molecules of [[nitric oxide]] (about 5,000 [[Tonne|tons]] per Mt, 5 × 10<sup>9</sup> grams per megaton)<ref name="Goldsmith 1973"/><ref>[http://nuclearweaponarchive.org/Nwfaq/Nfaq5.html Nuclear weapons archive, Carey Mark Sublette 5.2.2.1] {{Webarchive|url=https://web.archive.org/web/20140428174041/http://nuclearweaponarchive.org/Nwfaq/Nfaq5.html |date=2014-04-28 }} "The high temperatures of the nuclear fireball, followed by rapid expansion and cooling, cause large amounts of nitrogen oxides to form from the oxygen and nitrogen in the atmosphere (very similar to what happens in combustion engines). Each megaton of yield will produce some 5000 tons of nitrogen oxides."</ref> are believed to have entered the stratosphere, and while ozone depletion of 2.2 percent was noted in 1963, the decline had started prior to 1961 and is believed to have been [[Ozone depletion|caused by other meteorological effects]].<ref name="Goldsmith 1973"/>

In 1982 journalist [[Jonathan Schell]] in his popular and influential book ''[[The Fate of the Earth]]'', introduced the public to the belief that fireball generated NOx would destroy the ozone layer to such an extent that crops would fail from solar UV radiation and then similarly painted the fate of the Earth, as plant and aquatic life going extinct. In the same year, 1982, Australian physicist [[Brian Martin (social scientist)|Brian Martin]], who frequently corresponded with John Hampson who had been greatly responsible for much of the examination of NOx generation,<ref name="bmartin.cc1" /> penned a short historical synopsis on the history of interest in the effects of the direct NOx generated by nuclear fireballs, and in doing so, also outlined Hampson's other non-mainstream viewpoints, particularly those relating to greater ozone destruction from upper-atmospheric detonations as a result of any widely used [[anti-ballistic missile]] ([[ABM-1 Galosh]]) system.<ref>{{Cite web |author=Martin |first=Brian |date=1988 |title=John Hampson's warnings of disaster |url=http://www.bmartin.cc/pubs/88Hampson.html |url-status=live |archive-url=https://web.archive.org/web/20141130145905/http://www.bmartin.cc/pubs/88Hampson.html |archive-date=2014-11-30 |access-date=2014-10-03 |quote=Crutzen of course knew of Hampson's work, and also had received correspondence from Hampson around 1980. His own impression was that nuclear explosions above the stratosphere probably wouldn't lead to nitrogen oxides at a low enough altitude to destroy a lot of ozone.}}</ref> However, Martin ultimately concludes that it is "unlikely that in the context of a major nuclear war" ozone degradation would be of serious concern. Martin describes views about potential ozone loss and therefore increases in [[Ultraviolet|ultraviolet light]] leading to the widespread destruction of crops, as advocated by Jonathan Schell in ''[[The Fate of the Earth]]'', as highly unlikely.<ref name="Figure 1" />

More recent accounts on the specific ozone layer destruction potential of NOx species are much less than earlier assumed from simplistic calculations, as "about 1.2 million tons" of natural and [[wikt:anthropogenic|anthropogenic]] generated stratospheric NOx is believed to be formed each year according to Robert P. Parson in the 1990s.<ref>{{cite web|url=http://stason.org/TULARC/science-engineering/ozone-depletion-intro/24-Will-commercial-supersonic-aircraft-damage-the-ozone-laye.html |title=24 Will commercial supersonic aircraft damage the ozone layer?|first=Stas |last=Bekman |website=stason.org|access-date=2014-10-03|url-status=live|archive-url=https://web.archive.org/web/20160606051736/http://stason.org/TULARC/science-engineering/ozone-depletion-intro/24-Will-commercial-supersonic-aircraft-damage-the-ozone-laye.html|archive-date=2016-06-06}}</ref>

==== Science fiction ====
The first published suggestion that cooling of the climate could be an effect of a nuclear war, appears to have been originally put forth by [[Poul Anderson]] and F. N. Waldrop in their story "Tomorrow's Children", in the March 1947 issue of the ''[[Astounding Science Fiction]]'' magazine. The story, primarily about a team of scientists hunting down [[mutant (fiction)|mutants]],<ref>{{cite book |author=Ashley |first=Michael |title=The History of the Science Fiction Magazine |volume=1 |page=186 |language=en-us}}</ref> warns of a "[[Fimbulwinter]]" caused by dust that blocked sunlight after a recent nuclear war and speculated that it may even trigger a new Ice Age.<ref>{{Cite encyclopedia |title=Nuclear Winter|encyclopedia=Science Fiction Encyclopedia |url=http://www.sf-encyclopedia.com/entry/nuclear_winter#sthash.x25SIeys.dpuf|access-date=2018-09-13 |archive-url=https://web.archive.org/web/20180728074452/http://www.sf-encyclopedia.com/entry/nuclear_winter#sthash.x25SIeys.dpuf|archive-date=2018-07-28|url-status=live}}</ref><ref name=autogenerated5>{{cite web|url=http://www.aip.org/history/climate/Winter.htm#N_1_|title=Wintry Doom |website=www.aip.org|access-date=2014-09-23|archive-url=https://web.archive.org/web/20140929134255/http://www.aip.org/history/climate/Winter.htm#N_1_|archive-date=2014-09-29|url-status=live}}</ref> Anderson went on to publish a novel based partly on this story in 1961, titling it ''Twilight World''.<ref name=autogenerated5 /> Similarly in 1985 it was noted by T. G. Parsons that the story "Torch" by C. Anvil, which also appeared in ''Astounding Science Fiction'' magazine, but in the April 1957 edition, contains the essence of the "Twilight at Noon"/"nuclear winter" hypothesis. In the story, a nuclear warhead ignites an oil field, and the soot produced "screens out part of the sun's radiation", resulting in Arctic temperatures for much of the population of North America and the Soviet Union.<ref name="babel.hathitrust.org" />