I find this growing ignorance about the implications of nuclear warfare disturbing, especially in a time where I hear serious talk by experts about the feasibility of so-called “tactical” nuclear weapons, and in which the news that North Korea now has the bomb is overshadowed by the latest developments in Britain's Got Talent. So I am devoting this blog entry to the rather depressing subject of nuclear holocaust. It is surprisingly hard to find much decent literature on the subject that has been written after the 1980s, which explains why the sources I provide seem a bit dated. Also, I apologise in advance to non-American readers for not providing figures in metric units, but unfortunately most of the literature is American.
The following scenario describes the likely effects of a 1-megaton blast striking a large American city with a population of around 1 million people, and a population density of 13,000 people per square mile. To give some scale, a megaton is equivalent to 1 million tons of TNT, where the bomb that was dropped on Hiroshima was about 12 kilotons (i.e. 12,000 tons of TNT). In describing the effects of such a nuclear blast, we must also distinguish between a ground burst and an air burst, the latter being capable of more damage.
In a ground burst directed at the city centre, all buildings up to 2 miles from ground zero (an area of 10 square miles) will be completely demolished. This means that almost everyone In this area will likely be killed by having their bodies collide with material objects.
A further mile out from the centre, more buildings will be destroyed and around 50 % of the population will be killed by collision, with a further 40% seriously injured. Thus, in the 3 mile radius from the centre of the blast we can expect the total dead to be around 250,000 people. An air burst would increase this lethality by about 50%, making for a total of 350,000 to 450,000.
Whether a ground burst or an air burst, the strike would produce a mile-wide fireball as hot as the surface of the sun, with a 10-second burst of intense radiant heat. Almost everything within 5 miles of a ground burst (75 square miles) will die of third-degree burns. Scores of thousands more will be badly burned. Besides burns from the immediate blast, additional people will be burned by ignited combustibles. While processing these numbers, keep in mind that there are only around 2000 burn beds in the entire US.
Within one and a half miles of ground zero, anyone in the open would be killed by an initial pulse of gamma radiation, but this is gratuitous, since heat and blast will have killed them anyway.
Dust and debris sucked up in the blast will be irradiated and in a few minutes these will begin to spread as visible fallout. Depending on prevailing weather conditions, radiation during the first 24 hours could lethally dose 100,000 of those remaining. In any case, the city would be rendered lethal to enter, so any “survivors” would have no hope of rescue.
THUS, A ONE-MEGATON AIR BURST CAN BE EXPECTED TO KILL AROUND 500,000 PEOPLE, OR HALF THE POPULATION.
Unfortunately, this scenario is conservative, for the following reasons. First, it assumes a population density of 13,000 people per square mile, but many major US cities are much more densely populated than this. Second, it assumes only one direct hit on the city. But most strategic planning would call for multiple strikes on targeted cities, more in the neighbourhood of six to eight one-megaton warheads, plus more warheads of smaller size. Third, a one-megaton warhead is not nearly the most powerful weapon in the US or Russian nuclear arsenals. For example, the now phased-out Titan IIs yielded 9 megatons, and there are still other weapons with a similar yield. Fourth, the scenario assumes that only the one city is hit. With simultaneous strikes on other cities, the hope of outside help or rescue becomes diminishingly plausible.
In short, a strategically realistic 100-megaton attack on the 16 major US metropolitan areas could be expected to kill 90% of inhabitants. A 200-megaton attack on only military targets in Britain, keeping in mind the proximity of such targets to civilian population centres, would likely kill around two-thirds of that country’s population.
It gets worse. Following the initial nuclear strikes, the skies would be darkened fro three weeks or so by vast clouds of smog created by burning cities, forests, and uncapped oil and gas wells, causing temperatures in the northern hemisphere to drop precipitously. The National Research Council, in a 1985 report to the US Defense Department, estimated a 99% reduction in sunlight, making it 50 degrees Fahrenheit cooler, enough to freeze lakes and reservoirs, cutting off water supplies in many areas. And it’s easy to imagine the effects this change would have on crops.
Radioactive fallout would continue to spread, contaminating people, natural life, and food supplies. Damaged infrastructure would make it impossible to move food supplies (assuming the existence of an undamaged reserve) to areas where it is needed. Thus, many can be expected to starve. Large areas will be further polluted by damaged nuclear, chemical, and other industrial facilities.
With high altitude air bursts we can also expect deterioration of the earth’s protective ozone layer, exposing survivors to larger doses of UV rays, causing blindness, cancers, and burned crops.
Finally, millions of unburied corpses would provide food for rats and radiation-resistant insects, as well as a vector for diseases.
Portraying people staring up calmly at mushroom clouds — unincinerated and unsickened by radiation — is an insult to those of us who spent much of our childhoods worrying about a coming nuclear holocaust, and whose sleeping lives were haunted by recurrent nuclear nightmares. Such ignorantly cavalier portrayals are not so different from those old “information” films from the 1950s we now like to laugh at, in which children are taught that their school desks will shelter them from the warheads raining down on them.
As a North American, I remember losing many nights’ sleep after seeing The Day After (1983). Although frightening enough, even The Day After was more optimistic than the facts warranted. Those who are interested in a more realistic depiction of a nuclear-stricken world might want to watch the 1984 British made-for-television movie Threads.
FINNIS, John, Joseph M. BOYLE, and Germain GRISEZ. Nuclear Deterrence, Morality and Realism. Oxford: Clarendon Press, 1987.
KATZ, Arthur M. Life After Nuclear War: The Economic and Social Impact of Nuclear Attacks on the United States. Cambridge, MA: Ballinger, 1982.
Office of Technology Assessment, US Congress. The Effects of Nuclear War (1979). London: Croom Helm, 1980.