# Nuclear Winter



## Zipper730 (Jul 21, 2019)

Nuclear winter - Wikipedia



> In 1952, a few weeks prior to the Ivy Mike (10.4 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_, whose distribution 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.[67]
> 
> 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 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 1 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."[68] 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.[69]


I'm curious when they say "tightly controlled" in the first paragraph (1952) if this included the President or Secretary of Defense? It sounds ridiculous but there are security clearance levels higher than the President of the United States, as weird as that sounds...

As for the 1956-57 reports: Would this have reached the Secretary of Defense or President of the United States?


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## tyrodtom (Jul 22, 2019)

What would make you think the President wouldn't have access to " tightly controlled" information ?
Saying something is " tightly controlled " really tells you nothing about how it was classified .

There's confidential, secret, then top secret, you'll only allowed to see information your cleared for, then another requirement is that you have the " need to know".
Just because you have a Top Secret clearance doesn't mean you can see all top secret and below information, in addition to the clearance you have to have to need the information to do whatever job you're assigned to do.
Then above Top Secret, there's Top Secret Cryto, which deals with codes, and just people who deal with codes have access to that.
There may be other clearances I know nothing about, because I didn't need to know of them.

I had a Top Secret clearance myself for about 2 years in the USAF, it took about 6 months to get it.
They did a national agency check, and the FBI came around and interviewed my old high school teachers, old employers, neighbors, but not anyone kin to me.
But after moving to a job that didn't require a TS clearance, my TS clearance wasn't renewed, and I was downgraded to a secret clearance

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## Zipper730 (Jul 22, 2019)

tyrodtom said:


> What would make you think the President wouldn't have access to "tightly controlled" information?


Well, there were security clearance levels that went above the President of the United States (crazy as that sounds), and people periodically hide information from superiors for all sorts of reasons. I'm not a totally distrusting, but, well, some people are self-serving dicks, who don't care about the greater good.


> Saying something is " tightly controlled " really tells you nothing about how it was classified.


True enough, Confidential, Secret, Top Secret, I didn't know there was Top Secret Crypto, but I know there's TS/SCI, and of course "Need to Know" which is self explanatory.


> I had a Top Secret clearance myself for about 2 years in the USAF, it took about 6 months to get it. They did a national agency check, and the FBI came around and interviewed my old high school teachers, old employers, neighbors, but not anyone kin to me.


I'm guessing they didn't ask family because family usually side with each other.


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## MIflyer (Jul 22, 2019)

We now know that the Nuclear Winter concerns that were raised back in the 1980's and that attracted so much concern from people such as Carl Sagan were in fact Soviet propaganda. They cooked the books in hope of weakening our nuclear weapons programs, the idea being advanced amounted to, "Why shoot back if it means the end of the world, anyway?"

As for classification of material, let's just say there are multiple levels of security classification that differ according to the type of material being protected. Some classifications "Do Not Exist." The Dept of Energy has its own classifications, and having a DoD security clearance does not convey the same degree of clearance at DoE.


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## Zipper730 (Jul 23, 2019)

MIflyer said:


> We now know that the Nuclear Winter concerns that were raised back in the 1980's and that attracted so much concern from people such as Carl Sagan were in fact Soviet propaganda.


The data came from a program code that was used in 1983. I wouldn't be surprised if the data was exploited for all sorts of reasons. 

Disinformation would be an obvious one
It would generate public opposition against nuclear weapons programs
While I'm not for censoring disinformation (from both a civil liberties and practicality standpoint -- it can be seen as a coverup): Disinformation should be countered quickly, or it'll spread. Saying "I'm not going to dignify that with a response", doesn't do it: Such failure to respond results in the whole matter being seen as evidence of guilt. Consider this: Many people still believe that Fort Detrick created HIV to kill off homosexuals, and African Americans.

People opposed to nuclear war would be another group: There are quite a number of people who would hop on the bandwagon, including...
Scientists: Many were not proponents of nuclear war, and had some reasons to be this way... 
Nuclear weapons can cause an amazing amount of destruction very quickly (basically each bomb does the damage of a WWII air-raid) and, while air-bursts don't produce much persistent radiation; some warheads were to be detonated as ground-bursts, which would produce persistent radiation.
They likely saw the US military (in particular the USAF and USN) as being far too eager to use them.
If they were had become aware of studies made in the 1950's and 1960's (something that does happen periodically as, stuff is usually classified for a limited period of time and, for various reasons, people do sometimes disclose information): This would definitely add concern over the threat to the environment
During nuclear tests in the Pacific, there were cases where radiation scattered over large areas.

Environmentalists: They were quite concern with the state of environmental pollution, whether caused by business or government
Radioactive materials were known to cause birth defects, to cause cancer, and to be fatal to human beings
Most people don't realize that the bulk of harm caused by radiation were released in the uncontrolled fission reaction that also produced the fires and blast-wave: Since the bomb was detonated in an air-burst, there was little persistent radiation except from precip (black rain as it was called); that said: Ground bursts do cause persistent radiation release.


Among both scientists and environmentalists is an attitude among some that, if the cause is justified, one can exaggerate or lie for the greater good.


> Some classifications "Do Not Exist."


Understood

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## tyrodtom (Jul 23, 2019)

Most nuclear test were air burst, and then several below ground test ( well below ground level).
But how many, if any, test were done at ground level, or just slightly below ground, like you'd get if you were trying to destroy a below ground missile silo?

So how do we know how much dust could be lofted into the air from a real nuclear exchange, where a good proportion might be targeted at underground installations?

Sagan did admit to error in his assessment in how much world wide temperatures might drop from the Kuwait oil fires set after Desert Storm 1.
Not everyone who thinks nuclear war might be bad for humanity's future is a communists dupe.

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## Greg Boeser (Jul 23, 2019)

Zipper730 said:


> The data came from a program code that was used in 1983. I wouldn't be surprised if the data was exploited for all sorts of reasons.
> 
> 
> Among both scientists and environmentalists is an attitude among some that, if the cause is justified, one can exaggerate or lie for the greater good.


And politicians, and professional military...

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## michael rauls (Jul 23, 2019)

The nuclear winter thing sounds quite plausible as large volcano eruptions that spewed debris into the atmosphere have resulted in a season of cooler than normal temperatures. I don't know that I buy that it would last years though. 
I suppose that it is somewhat academic though as a large scale nuclear exchange would make for a really bad day nuclear winter or no nuclear winter.


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## Zipper730 (Jul 24, 2019)

I'm curious how much debris (non-radioactive from burning cities, and radiation from bomb detonation or ground-bursts where applicable) would be pumped up into the atmosphere and how much of an effect this would produce to our environment.

South East Asia as Proposed by LeMay
Vietnam
Kep airfield struck; additional fields stuck as need be
Petroleum, oil, and lubrication hammered
Mining of Haiphong
Raids executed on Hanoi and Haiphong at the minimum like done in Linebacker II, and at maximum as incendiary area raids turning each city into blowtorches
Raids executed on a few of the smaller cities

China
Cratering of airfields in China
Firebombing of cities in China
Attack on Lop Nor nuclear plant with conventional or nuclear ordinance
A total of 5-10 nuclear bombs expended


Korean War Scenario gone Nuclear
30-50 cities in China, or China & North Korea were struck with nuclear bombs of the Mark 3-4 types: I'm not sure what targets would have been attacked as Ground Bursts or not
B-29's would deliver the payloads

1949 Bombing Plans as Proposed by LeMay
133 nuclear bombs to be delivered to cities, military targets, or industrial sites as LeMay would have dictated most likely
Firebombing to be executed when nuclear bombs were available.

Consider a few degrees of global temperature may have significant climate effects, at least from what I've been told. This should be on the science only, not into the political area.

Yes, I know this is morbid, but I'm simply curious if any of these scenarios would have rendered us extinct.


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## GrauGeist (Jul 24, 2019)

Nothing man-made (so far) can equal volcanic eruptions, and it's been verified that major volcanic events can and have altered weather patterns for a year and up to several years.

A major volcanic eruption immediately thrusts thousands of metric tons of ash and pumice into the stratosphere, where it's dispersed globally by the jet stream. This in turn has spawned "mini ice ages" within human history.

Archaeologic evidence has shown that the Super Caldera eruptions have gone as far as to alter climate.

So a "Nuclear Winter" is not all that far fetched of a notion...


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## mikewint (Jul 24, 2019)

On April 5, 1815, the Mount Tambora volcano began a four month eruption that ended when the volcano exploded in the largest volcanic explosion in recorded history, 10 times more powerful than Krakatoa. Thousands of people near the volcano were killed outright by the force of the explosion and the resulting pyroclastic cloud. While in the East Indian region 90,000 would soon die. During the eruption Mount Tambora ejected so much (100 cubic kilometers) ash and aerosols (sulfur dioxide) into the atmosphere that the sky darkened and the Sun was blocked from view for months. Larger particles fell to the ground nearby, covering towns with enough ash to collapse homes. Several feet of this ash covered the surface of the ocean and ships had to plow through it to get from place to place.

The smaller particles and aerosols ejected by the volcano reached into the stratosphere,where they were distributed around the world. Far more important than the particulate matter is the sulfur dioxide. Sulfur dioxide gets converted into sulfuric acid, which then forms aerosols high up in the atmosphere that also serve to block incoming solar radiation for several years after the eruption. The resulting long term blockage of the sun’s rays reaching the Earth dropped the average global temperature by three to six degrees Celsius.

In the eastern United States summer temperatures fell back below freezing, and communities from New England to Virginia experienced heavy snowfalls and crop-killing frost during June, July and August. Many of these Easterners moved further south and west to escape the cold. The influx of people triggered the western expansion of the US.

The crop failures caused grain prices to soar. Some poorer Americans were even reduced to eating hedgehogs and scrounging for wild turnips. In New England, 1816 was nicknamed “Eighteen-Hundred-and-Froze-to-Death”. On July 4th of that year, for instance, the high temperature in Savannah, Georgia, was only 46° F. As far south as Pennsylvania, lakes, and rivers were frozen over during July and August.

In Europe winter snows refused to melt, and between April and September, some parts of the Continent were drenched by as many as many as 130 days of rain. Harvests perished in frost and drought or were washed away by flooding rains. Crop failures across Europe and China caused deadly famines and outbreaks of typhus and other diseases. Germans would call 1817 “The Year of the Beggar”. In India, the disturbances gave rise to a virulent new strains of cholera and typhus that eventually killed millions.

Mary Shelley, her husband, the poet Percy Bysshe Shelley, and poet Lord Byron were on vacation at Lake Geneva. While trapped indoors for days by constant rain and gloomy skies, Mary Shelley wrote Frankenstein, a horror novel set in an often stormy environment. Lord Byron wrote the poem Darkness, which begins, “I had a dream, which was not all a dream. The bright sun was extinguish’d.” John Polidori was inspired to write The Vampyre, which later influenced Bram Stoker's Dracula.

Because the price of oats increased, it was more expensive for people to feed their horses so with expensive oats, the cost of travel increased. A German named Karl Drais invented a way to get around without a horse: the bicycle (Fred Flintstone style) was born.

Thomas Jefferson’s Mount Vernon was an income producing farm. That year’s extreme weather caused Jefferson’s crops to fail for several years afterward, heavily contributing to the Jefferson’s already-considerable debt. Jefferson never recovered financially, and he lived the rest of his life deeply in debt.

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## Zipper730 (Jul 24, 2019)

Greg Boeser said:


> And politicians, and professional military...


Yeah, but politicians can go either way, and the military would be likely to under-rate such things.


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## Greg Boeser (Jul 24, 2019)

Depends on what they are selling...
Never pass up an opportunity to exploit a crisis, even a theoretical one.

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## MIflyer (Jul 25, 2019)

The last full-fledged Ice Age ended in 9600 BC. It seems that it ended due to a massive outpouring of energy from the Sun that all by itself wrecked civilizations as well as causing the melting of the ice sheets that covered most of the land.

The period of about 1300 -1800 is known as the Little Ice Age. We know from records of sunspots that Solar output was lower then. In contrast, the last half of the 20th Century was marked by more Solar activity than in the last 10,000 years. Around the year 2000 scientists observing the Sun noted that solar surface currents were lower than they ever have been since such observations began in the 1890's. The prediction was that circa 2020 Solar sunspots - and energy output - would drop off, and that has occurred.


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## Barrett (Jul 25, 2019)

A late friend and colleague, retired VADM, specialized in Naval Nukes. He said he was a-mazed at what Ikenhower did not know about the subject, and apparently was not overly concerned about tracking the inventory. In context, that could help explain the 1960 campaign issue in which the Democrats (!) complained about a Nuke Gap, whether it existed or not. It's hardly as if We revealed Our Numbers or publicly discussed Their Numbers--the flail had to be taken on faith, which of course is a rare commodity in politics.


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## MIflyer (Jul 25, 2019)

Hard to believe that JFK attacked the Republicans from the Right, complaining about them not doing enough to stop Communism both in terms of nuclear capabilities as well as in the Third World. But Ike's Admin was like a duck, serenely cruising on the surface while paddling like mad below; they knew things they were not saying out loud. Both JFK and RMN were dedicated cold warriors. The night before his election to President, JFK told some close friends, "If I were not running myself, tomorrow I would be voting for Nixon."


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## Zipper730 (Jul 25, 2019)

Greg Boeser said:


> Depends on what they are selling... Never pass up an opportunity to exploit a crisis, even a theoretical one.


That's unfortunately, a sad fact.



MIflyer said:


> The prediction was that circa 2020 Solar sunspots - and energy output - would drop off, and that has occurred.


Sunspots worry me a bit, as that can result in coronal mass ejections. There was one in 1859, the Carrington Event, which produced some interesting results. 1972 saw some amazingly bad activity (it was arguably as bad as the Carrington event, it's just that we were grazed instead of directly clobbered) that caused outages, in 1989 saw some outages in Canada, and July 23, 2012 saw us miss a massive CME.



Barrett said:


> A late friend and colleague, retired VADM, specialized in Naval Nukes. He said he was a-mazed at what Ikenhower did not know about the subject, and apparently was not overly concerned about tracking the inventory.


That's kind of amazing. I assume the USN & USAF probably did their best to keep track of the inventory?


> In context, that could help explain the 1960 campaign issue in which the Democrats (!) complained about a Nuke Gap, whether it existed or not.


First there was the bomber gap, then the missile gap.


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## GreenKnight121 (Jul 25, 2019)

As for the findings of the report discussed in the first post, that report was considering the environmental effects of a SINGLE weapon - therefore it is not surprising that the conclusion was "no appreciable effects".

It is only when we get into the hundreds, and even thousands of warheads that the effects become "appreciable" and even "significant" - as noted in the final quoted sentence.


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## RCAFson (Jul 25, 2019)

GreenKnight121 said:


> As for the findings of the report discussed in the first post, that report was considering the environmental effects of a SINGLE weapon - therefore it is not surprising that the conclusion was "no appreciable effects".
> 
> It is only when we get into the hundreds, and even thousands of warheads that the effects become "appreciable" and even "significant" - as noted in the final quoted sentence.



Yes, and then we have to consider the effects of hundreds or thousands of cities burning uncontrollably for days and the potential for massive forest fires as well.


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## Zipper730 (Jul 26, 2019)

GreenKnight121 said:


> As for the findings of the report discussed in the first post, that report was considering the environmental effects of a SINGLE weapon - therefore it is not surprising that the conclusion was "no appreciable effects".


Which report are we talking about? There were a few mentioned just in the opening post. Regardless, it seems to make sense that a couple of hundred nuclear weapons going off would have substantial effects on the environment.



RCAFson said:


> Yes, and then we have to consider the effects of hundreds or thousands of cities burning uncontrollably for days


I figure it could be burning for weeks. From what I remember the fires in Hamburg were still burning all the way into August of 1943, from what I recall.


> and the potential for massive forest fires as well.


If they were near enough to the blasts, yeah, that would produce considerable soot. I'm not sure which would do more, that or a city.

There's also two other factors I was thinking of, which I'm not sure were ever addressed

Low-Altitude/Ground-Bursts/Subterranian Detonations
If I recall, air-burst maximize blast and fire-damage to un-hardened structures: The fire damage would produce a lot of combustion that would proceed for quite a while
Ground bursts might not have as much blast and fire damage over the largest area, but blast damage might have a higher overpressure right where the bomb went off: It would produce a lot of persistent radiation
Subterranean Detonations: I would imagine it would scatter huge amounts of debris into the air, and much of it appears to be radioactive.

Nuclear Reactor Attacks: I could just imagine that would produce some spectacular fall out. I know to some extent you'd see quite a lot of fission, but the heat of that blast would just vaporize so much material and scatter it.


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## GrauGeist (Jul 26, 2019)

The most damaging nukes are the ones of high yield, which churn up debris and broadcast that matter into the stratosphere (like a volcano).
While an air-burst type detonation has it's strategic value, it won't present a significant threat to weather/climate.
It's the nukes that burrow and detonate or ground-burst, that present a problem globally.


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## Zipper730 (Jul 26, 2019)

GrauGeist said:


> The most damaging nukes are the ones of high yield, which churn up debris and broadcast that matter into the stratosphere (like a volcano).


That's correct, and there were warheads that were designed for lay-down delivery. There was also some war-plans from the 1950's that revealed proposals to use ground-bursts in some cases: Probably to produce a tremendous overpressure on a small area (like a hardened target) versus a large amount over a large area (area-target). 

What really struck people as surprising was that "population" was sometimes specified as a target (I gotta say, I'm impressed with their candidness -- usually there's various euphemisms that obscure the nature of stuff like that), though I'm not sure if it was needed (several nukes would often be assigned to nearby targets).


> It's the nukes that burrow and detonate or ground-burst, that present a problem globally.


I assume the ones that penetrate would probably be the worst, the B53 was designed to be able to dig into the ground before detonating. I'm not sure how far down it'd go, but if you could dig in 280 feet and detonate with just 5MT of force, you could make Meteor crater.


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## mikewint (Jul 26, 2019)

In 1982, the journal of the Royal Swedish Academy of Sciences, Ambio, published an article that discussed the issue of smoke generated by the nuclear-ignited burning of forests and grasslands. The article discussed the effect of the smoke generated causing changes in continental weather patterns. As bad as that was, later studies found that the smoke from urban fires posed an even greater global hazard in the form of a “Nuclear Winter” that was capable of causing a worldwide collapse of agriculture. Modern climate models not only show that the nuclear winter theory is correct, but also that the effects would last for more than a decade because of an unexpected phenomenon: Smoke would rise to altitudes of 40 kilometers (25 miles). At such a height it would be protected from rain and would therefore take more than a decade to clear completely. Thus the smoke’s climate impacts would be more extreme than had once been thought.

The new models show that a full-scale nuclear conflict, in which 150 million tons of smoke are lofted into the upper atmosphere, would drastically reduce precipitation by 45 percent gloabally, while temperatures would fall for several years by 7 to 8C (12 to 14F) and would remain depressed by 4C (7F) after a decade. Global temperatures have not been this low since the last ice age. In important grain-growing regions of the northern mid-latitudes, precipitation would decline by up to 90 percent, and temperatures would fall below freezing and remain there for one or more years.

For instance in a nuclear exchange between the major powers, the use of 4,000 weapons (the rough total for US and Russian arsenals in 2017 under New START), each with a yield of 100 kilotons (a typical yield for submarine weapons, but at the low end for most nuclear weapons), against urban or industrial targets would produce about 180 million tons of soot. A single US submarine carrying 144 weapons of 100-kiloton yield could produce 23 million tons of smoke if these weapons were used on densely populated Chinese cities.

Let’s now consider a smaller scale regional nuclear war (India – Pakistan) involving the use of just 100 Hiroshima-size weapons. In these simulations, more than five million tons of smoke is lofted to high altitude, where it absorbs sunlight before the light can reach the lower atmosphere. As a result, surface temperatures fall and precipitation declines. The calculated results show a 10 percent global drop in precipitation, with the largest losses in the low latitudes due to failure of the monsoons. The predicted climate model also shows global average temperatures colder than any experienced on Earth in the past 1,000 years and growing seasons shortened by two to three weeks in the main mid-latitude agricultural areas of both hemispheres. These effects would persist for several years, threatening a significant fraction of the world’s food supply. At present at least a billion people are now only marginally fed as it is. New simulations of the effects of these climate changes on crop production predict reductions of soybean and corn production in the US Midwest, and of rice production in China, of 20 percent for several years and 10 percent even after a decade. The smoke would also heat the upper atmosphere by as much as 50 degrees Celsius for several years. As a consequence, ozone levels over the mid-latitudes of both hemispheres would be reduced to values now found only in the Antarctic ozone hole allowing large amounts of UV-radiation to reach the surface.


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## Zipper730 (Jul 26, 2019)

mikewint said:


> For instance in a nuclear exchange between the major powers, the use of 4,000 weapons . . . . each with a yield of 100 kilotons


The bombs we had in 1962 were well above that on average.


> The smoke would also heat the upper atmosphere by as much as 50 degrees Celsius for several years. As a consequence, ozone levels over the mid-latitudes of both hemispheres would be reduced to values now found only in the Antarctic ozone hole allowing large amounts of UV-radiation to reach the surface.


So there'd be radiation from the blasts, and radiation from the ozone depletion. I assume that would contribute to massive cancer deaths...


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## mikewint (Jul 27, 2019)

The only real Nuclear Bomb data remains the effects of the bombs dropped on Hiroshima and Nagasaki. There were, of course only two bombs involved and they were, by today's standards, small low yield bombs: Little Boy 13-18 kt TNT and Fat Man 20-22 kt TNT. By comparison the USSR's Tsar Bomb, as tested with a lead damper yielded 500,000 kt TNT and with a depleted uranium damper should reach 100 Mega tons of TNT.

Approximately 200,000 people died in the bombings and their immediate aftermath, mainly from the explosive blast, the firestorm it sparked, and from acute radiation poisoning. Around half of those who survived subsequently took part in studies tracking their health over their entire lifespan. These studies began in 1947 and are now conducted by a dedicated agency, the Radiation Effects Research Foundation, The project has followed approximately 100,000 survivors, 77,000 of their children, plus 20,000 people who were not exposed to radiation.

Cancer rates among survivors were higher compared to rates in those who had been out of town at the time. The relative risk increased according to how close the person was to the detonation site, their age (younger people faced a greater lifetime risk), and their sex (greater risk for women than men). However, most survivors did not develop cancer. Incidence of solid cancers between 1958 and 1998 among the survivors were 10% higher, which corresponds to approximately 848 additional cases among 44,635 survivors in this part of the study. However, most of the survivors received a relatively modest dose of radiation. In contrast, those exposed to a higher radiation dose of 1 Gray (approximately 1000 times higher than current safety limits for the general public) bore a 44% greater risk of cancer over the same time span (1958-1998). Taking into consideration all causes of death, this relatively high dose reduced average lifespan by approximately 1.3 years.

Although no differences in health or mutations rates have yet been detected among children of survivors, However, more subtle effects might one day become evident, perhaps through more detailed sequencing analysis of their genomes. For the present it seems clear that even if the children of survivors do in fact face additional health risks, those risks must be very small.


*The Gray*_ is the unit of absorbed radiation dose and has replaced the rad. 1 Gray = 1 Joule/kilogram and also equals 100 rad. The Gray can be used for any type of radiation (e.g., alpha, beta, neutron, gamma), but it does not describe the biological effects of different radiations.
Biological effects of radiation are measured in units of "sievert" (or the older designation "rem").
Sievert is calculated as follows: gray multiplied by the "radiation weighting factor" (also known as the "quality factor") associated with a specific type of radiation.
To cause death within hours of exposure to radiation, the dose needs to be very high, 10Gy or higher, while 4-5Gy will kill within 60 days, and less than 1.5-2Gy will not be lethal in the short term._

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## swampyankee (Jul 27, 2019)

There is also limited data from US servicemen exposed during testing (see Other Studies of Radiation Exposure of Military Personnel - The Five Series Study - NCBI Bookshelf) and accidents, such as the _Lucky Dragon No. 5_ (Godzilla: The "Lucky Dragon" of Bikini Atoll | Naval Historical Foundation). Some data on the behavior of smoke can be obtained from the Kuwait War Oil FIeld fires (Environmental impact of Kuwait oil fires: upper atmosphere) and forest fires.


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## fubar57 (Jul 31, 2019)

The bombing of Hamburg lasted until Aug. 3 '43 so I'm sure it would have burned into August.


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