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May 24, 2012

Nuclear Famine Fears based on Faulty Assumptions

There is a 19 page study that predicts a nuclear famine if a previous study of a nuclear autumn is correct. The nuclear autumn article is not correct.

1. I will repeat my case on why nuclear winter does not happen
2. They then try to build upon a slight drop in temperature (that will not happen) in order to say their will be a 10% drop in agricultural production
3. The agricultural production drop is assumed to hit everyone who gets marginal food by 10% so that they all drop into starvation and die.

Looking at the unique conditions in Hiroshima

I have examined the case for climate effects of an exchange of nuclear weapons in detail.

A nuclear winter is predicated on current cities all reacting to nuclear weapons the Hiroshima did and having a firestorm in order to put a lot of soot into the stratosphere. I will summarize the case I made then in the next section. there is significant additions based on my further research and email exchanges that I had with Prof Alan Robock and Brian Toon who wrote the nuclear winter research.

The Steps needed to prove nuclear winter:
1. Prove that enough cities will have firestorms or big enough fires (the claim here is that does not happen)
2. Prove that when enough cities in a sufficient area have big fire that enough smoke and soot gets into the stratosphere (trouble with this claim because of the Kuwait fires)
3. Prove that condition persists and effects climate as per models (others have questioned that but this issue is not addressed here

The nuclear winter case is predictated on getting 150 million tons (150 teragram case) of soot, smoke into the stratosphere and having it stay there. The assumption seemed to be that the cities will be targeted and the cities will burn in massive firestorms. Alan Robock indicated that they only included a fire based on the radius of ignition from the atmospheric blasts. However, in the scientific american article and in their 2007 paper the stated assumptions are:

assuming each fire would burn the same area that actually did burn in Hiroshima and assuming an amount of burnable material per person based on various studies.

The implicit assumption is that all buildings react the way the buildings in Hiroshima reacted on that day.

Therefore, the results of Hiroshima are assumed in the Nuclear Winter models.
* 27 days without rain
* with breakfast burners that overturned in the blast and set fires
* mostly wood and paper buildings
* Hiroshima had a firestorm and burned five times more than Nagasaki. Nagasaki was not the best fire resistant city. Nagasaki had the same wood and paper buildings and high population density.




The 2007 study by Toon considered the consequences of a possible nuclear war between India and Pakistan and showed that such a conflict would loft up to 6.6 Tg (6.6 teragrams or 6.6 million metric tons) of black carbon aerosol particles into the upper troposphere. Robock et al then calculated the effect that this injection of soot would have on global climate assuming a war in South Asia occurring in mid May.

Mushroom Clouds and size of Bombs

Here is a chart with the height of mushroom clouds based on the yield of the weapons.


Nuclear weapons do not loft the material into the stratosphere from the explosion. It is from the setting the cities on fire in a firestorm.

A low-altitude detonation produces a cloud with dust loading of 100 tons per megaton of yield. A ground detonation produces clouds with about three times as much dust. About 200 tons per kiloton of soil, for a ground detonation, gets melted and comes in contact with radioactivity.

It is difficult to determine the actual size and composition of India's and Pakistan's nuclear arsenals, but NRDC estimates that both countries have a total of 50 to 75 weapons. Contrary to the conventional wisdom, the NRDC believe India has about 30 to 35 nuclear warheads, slightly fewer than Pakistan, which may have as many as 48.

Both countries have fission weapons, similar to the early designs developed by the United States in the late 1940s and early 1950s. NRDC estimates their explosive yields are 5 to 25 kilotons (1 kiloton is equivalent to 1,000 tons of TNT). By comparison, the yield of the weapon the United States exploded over Hiroshima was 15 kilotons, while the bomb exploded over Nagasaki was 21 kilotons.

The paper was talking about a war between India and Pakistan that it would cause many firestorms which would cause 5 million tons of soot to go into the stratosphere which would cause temperatures to drop 1.5 degrees which would cause agriculture production to drop 10% which would put 925 million undernourished people to die.

The US mostly has retired all of its big bombs. The United States has dismantled its last B53 9 megaton nuclear bomb. The next biggest bomb is the B83 which is 1.2 megatons. The B53 weighed 10,000 pounds and was the size of a minivan.

Directly sending material into the Stratosphere takes a bomb with about 1-20 megatons of yield (depending upon the location, at the equator or elsewhere). This is why the nuclear winter articles talk about city firestorms.

Russia has about 2400 active strategic nuclear weapons.


The AS15 have about 250 kiloton yield and the AS16 have 350 kilotons. It appears that all of the big multi-megaton weapons were retired. Newer missiles are more accurate and do not need the high tonnage.

Fire and Details - India and Pakistan buildings more burnt brick

If there are not multiple citywide firestorms then there is no trigger for nuclear winter even if the later modeling (which is still uncertain) would even need to be considered.
- The Material of the Houses in India and Pakistan do not appear to be Right for Firestorms (mostly burnt brick and mud)

Firestorms have always required at least 50% of buildings to be ignited. High percentage of builtupness is also necessary Hiroshima had most fires from overturned breakfast charcoal braziers.

References that provide the basis of my case Problems of Fire in Nuclear Warfare, Jerome Hill, Rand, 1961
- Nagasaki had no firestorm

4.4 square miles Hiroshima actual burned area

0.9 square miles Nagasaki

13.5 square miles maximum theoretical .




India building census indicates that most of the buildings are made from Burnt Brick, mud which are non-combustible.
Exploratory Analysis of Fire Storms, Stanford Research Institute, 1965

The frequency of rain in India or Pakistan is important because of the effect of recent rain on burning of cities.

Quantitive - seasonal rainfall patterns for India and Pakistan

Fire Factors

"Mass fires and Fire Behaviors" which studies fires in cities and other places indicates that combustible roofing material is a major cause of fires spreading in cities. This document also discusses how to reduce fire risks and lessen spreading of fires. The usual vegetation management that is commonly mentioned for LA fires and having non-combustible roofing materials and gaps between buildings. These anti-fire measures would apply to lessoning fires ignited by nuclear bombs too.
http://www.fs.fed.us/psw/publications/documents/psw_rp019/psw_rp019_part1.pdf
http://www.fs.fed.us/psw/publications/documents/psw_rp019/psw_rp019_part2.pdf
http://www.fs.fed.us/psw/publications/documents/psw_rp019/psw_rp019_part3.pdf

Steps to Reduce Damage

Simple civil defence and building improvements would reduce damage from nuclear war and from hurricanes and earthquakes. Haiti and New Orleans show the importance of building better to greatly reduce problems.

Hurriquake nails, outside paint that reflects heat and other cheap retrofits would reduce the damage radius and roofing material that does not burn.

Further improvement for buildings

There are also some basic counter measures against city wide fire.

Mount Pinotubo

EPA - Most volcanoes do not penetrate the stratosphere. In fact, only a small number of eruptions have produced a significant amount of aerosols in this century. (Note that volcanic aerosols are totally unrelated to consumer aerosol products, like hair spray, that have not used ozone-depleting substances since the 1970s.) One example is Mt. Pinatubo, which injected 30 million tons of aerosols into the stratosphere during its 1991 eruption in the Philippines.

Note - I believe likewise that most city firestorms would not penetrate the stratosphere and I have indicated that the firestorms would mostly not form in the first place because of the mostly burnt brick buildings and lower builtupness of the cities in India and Pakistan.

In 1992 and 1993, the average temperature in the Northern Hemisphere was reduced 0.5 to 0.6°C and the entire planet was cooled 0.4 to 0.5°C. The maximum reduction in global temperature occurred in August 1992 with a reduction of 0.73°C.

There was no spike in prices in 1992 or 1993 and there was no drop off in food production.

Number of Starvation deaths in the World

Of 57 million deaths that occur each year worldwide, the actual number of deaths attributed to starvation and malnutrition.

All Nutritional Deficiences Deaths    485,004 deaths 2002
---Deaths from Starvation             260,210 deaths 2002
---Vitamin A Deficiency Deaths         22,892 deaths 2002
---Iron Deficiency Anaemia Deaths     136,915 deaths 2002
---Iodine Deficiency Deaths             6,536 deaths 2002

UNICEF does indicate that undernutrition contributes to the death of 5 million children.

According to United Nations Children's Fund (UNICEF) report, 27% of children under 5 years of age in developing countries suffer from wasting. This is against the background evidence that malnutrition contributes to 54% of all deaths among children under 5 years of age. In Ghana, malnutrition accounts for 40% of under 5 mortality. The contribution of malnutrition to morbidity and mortality has been shown to be synergistic rather than additive. Thus mortality increases exponentially with declining nutritional status.

The concept of Integrated Management of Childhood Illnesses (IMCI) is based on the premise that sick children usually present with more than one medical condition to health facilities. It is therefore expected of health practitioners that all children who present to health facilities are well assessed so that the child could be managed in a holistic manner. Surveys of management of sick children at these facilities revealed that many of these children are not properly assessed and treated. That only 15 (5.9%) out of the 251 malnourished children were so identified by the attending physician support this observation.

Yes there are a lot of hungry and undernourished people but it is rarely translating into starvation deaths. It is a problem to be fixed but the scenario described in the report is wrong in terms of the firestorm effect, the temperature effect, the agricultural effect and then in the starvation effect. There are real risks but this is not one of them.

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