Effects of Nuclear Earth-Penetrator and Other Weapons (2005) / Chapter Skim
Currently Skimming:
8 Uncertainty in Estimates of Effects
8 Uncertainty in Estimates of Effects
Pages 103-109
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 103... ...
, surface-burst weapons, and conventional weapons, the performance of the weapons, the extent of target destruction, related prompt effects and effects of fallout, and the resultant health and environmental effects. For the model calculations, a range of boundary conditions has been assumed.
|
From page 104... ...
In addition, Figures 6.9 and 6.11 show that estimates of total casualties can vary by factors as large as 101 to 102, depending on wind direction.1 The general conclusion derived from such comparisons is that the estimated reductions in casualties from a nuclear EPW as opposed to a surface burst of 25-times-higher yield are about 2 to 50 times larger for rural than for urban targets, but the casualty estimates are also more variable by factors of 1 to 2 orders of magnitude in absolute values for the rural than the urban targets. To be sure, all else being equal, use of a weapon with a lower yield is always expected to result in fewer casualties than use of a weapon with a higher yield, for a given set of weather conditions.
|
From page 105... ...
Chapter 5 does note that the integrated dose contours reproduce to within a factor of two the nuclear test results from which the empirical models were derived; however, it is important to acknowledge that the nuclear tests were conducted in good weather and under relatively stable atmospheric conditions.3 Additional sources of uncertainty listed in Chapter 4 include the hardness of the target, the effects of the accuracy of weapons delivery (circular error probable, CEP) , and details of fallout assessment (e.g., the relationship between amount of radioactivity and size for particles in the fallout)
|
From page 106... ...
In terms of absolute numbers of fatalities and injuries, however, attacks on urban targets dominate overwhelmingly. That is, estimated casualties from the use of a nuclear weapon in an urban area are typically in the 105 to 106 range, whereas casualties from the rural targets considered in this study can be as low as in the 101 to 102 range (albeit potentially extending to the 105 range, depending on circumstances and assumptions)
|
From page 107... ...
.7,8 Similarly, mean absolute-value errors of ±30 to 40 degrees are documented for a model applied to the Savannah River Site in South Carolina, though with excursions reaching 60 to 70 degrees at 12 to 24 hours into the forecast.9 Not surprisingly, the statistics can be somewhat worse for topographically complex areas, such as the region around Salt Lake City, Utah, although mean absolute errors of ±40 to 50 degrees remain possible in many specific locations when extensive modeling and updating are pursued.10,11 In general, wind directions are more poorly forecast at lower than at higher wind speeds, and at lower (near-surface) than higher levels of the atmosphere.
|
From page 108... ...
Given that uncertainties in wind direction additionally cause variations of one order of magnitude or more, the aggregate uncertainty for calculations of casualties caused by the range of nuclear attack scenarios considered here must be squarely placed in the range of 101 to 102 (factors of 10 to 100) , with the lower range applying to urban targets for which casualties will with little doubt be very high.
|
From page 109... ...
Fast, 2003, "An Evaluation of the MM5, RAMS, and Meso-Eta Models at SubKilometer Resolution Using VTMX Field Campaign Data in the Salt Lake Valley," Monthly Weather Review, Vol.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.