Nuclear winter is the theory that severe and prolonged global climatic cooling will happen after a large-scale nuclear war. This assumes that fires can inject soot into the stratosphere. This would block some direct sunlight from reaching the surface of the Earth. This would then lead to widespread crop failure and famine. Nuclear-winter scenario researchers use the conventional bombing of Hamburm and the Hiroshima firestorm in World War II as example cases where soot might have been injected into the stratosphere.
The stratosphere is 6.2 miles up to an altitude of 31 miles (50 kilometers).
There is a 71 page analysis of firestorms from 1965 by Stanford Research Institute.
The nuclear winter case is predicated on getting 10 to 150 million tons (10 to 150 teragram case) of soot, smoke into the stratosphere and having it stay there for decades.
Natural ore manmade firestorms are capable of injecting soot smoke/aerosols into the stratosphere. The stratosphere has been cleared of any weather affecting soot from large forest fires in 2 to 8 months. Volcanioes have caused cooling for a couple of years.
The assumption seems to be that the cities will be targeted and the cities will burn in massive firestorms.
The Steps needed to prove nuclear winter:
1. Prove that enough cities will have firestorms.
2. Prove that when enough cities in a sufficient area have firestorms 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 fire storm created by a 20 kt weapon at Hiroshima burned out an area of over four square miles, and 68,C00 of Hiroshima’s 75,000 buildings were destroyed or damaged. The severely burned out area from the Hamburg fire storm was about the same size as that at Hiroshima; some 40,000-5O,000 people were killed by effects of the fire alone.
Nagasaki did not have a firestorm. Hiroshima did because of mostly paper walled buildings and bbq cookers.
Large city firestorm criteria are:
Fuel loading of over 8 pounds of combustibles per square foot of fire area
Fire density over 50% of structures in fire storm area on fire simultaneously (for practical purposes, initial fire density)
Surface wind less than 8 miles per hour it time of attack
Fire storm area over 0.5 square miles
Fuel loading is less and building density is less.
No firestorm is possible in any suburban or rural area. Three large houses per acre is less than 25% building coverage of land.
We would need cities with high multi-family units to get over 50% structures have fires at the same time. Multi-units tend to be built more of brick, stone and cement which are not as flammable.
There is less paper usage. Paper use has declined about 20%. There are fewer people getting newspapers and magazines via print editions.
Nuclear bombs do not add fuel, they just can ignite whatever is already there.
There have been plenty of large forest fires in California and across the USA.
There have been some fires with flammagenitus, pyrocumulus cloud, or fire clouds. There were about eight known incidents of these type of high altitude clouds formed from large fires.
There were dozens of fires in California and hundreds in the US and world but only eight had high altitude clouds over about 80 years.
Cities in the western world are more spread out. The materials used for buildings are less flammable. There is less paper and flammables in peoples houses. There is less likelihood for firestorms to occur. There would be virtually no firestorms.
The Kuwait oil fires burned 4-6 million barrels of oil per day and over 1 billion barrels of oil but did not trigger any major injection of soot into the stratoshere.
The nuclear winter people are stopped at proving there will be firestorms and proving there will be a lot of firestorms.
The next two steps also look bad. If there are a lot of firestorms (city and forest) then prove there will be a lot of soot injected into the stratosphere.
If there is a lot of soot in the stratosphere prove that it will stay up there for many years or decades instead of a few months like we are seeing now.
India and Pakistan use mostly buildigs with thin walls made of red burnt clay bricks and roofs are made of concrete.
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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