Computer Models of the Effects of Nuclear Attack on Britain: The Home Office and its Critics

Two computer models for predicting casualties in nuclear attacks on Britain are compared. One has been developed by the Scientific Research and Development Branch (SRDB) of the Home Office, the other by members of the organization Scientists Against Nuclear Arms (SANA), to which the author belongs. Both models take account of casualties from the effects of blast and fall‐out, and the SANA model also computes burns casualties from the direct effects of thermal radiation. The SANA model is very largely based on official American sources. There are no significant differences between the ways in which the two models predict the physical effects of nuclear explosions. However, there are large differences in casualty rates, by which these physical effects are translated into numbers of deaths and serious injuries. These differences all act in the same direction, to increase estimated casualties in the SANA model, relative to the predictions of the SRDB model, for similar attack patterns. The SANA model predicts, for attacks on Britain with up to 200 MT of nuclear weapons, 3–4 times more casualties from all causes than the SRDB model as it was described in Home Office publications in 1981 and 1982. Since that time the SRDB has it seems made changes to its casualty rates, which in some cases would narrow the differences between the two models. However, no revised casualty estimates have been published by the Home Office more recently.