A surface explosion will produce much more early fallout than a similarly sized air burst where the fireball never touches the ground. This is because a surface explosion produces radioactive particles from the ground as well as from the weapon. The early fallout will drift back to earth on the prevailing wind, creating an elliptical pattern stretching from ground zero out into Long Island. Because the wind will be relatively light, the fallout will be highly concentrated in the area of Manhattan just to the east of the blast. Predicting levels of radiation is difficult and depends on many factors like bomb size, design, the ground surface and soil type.
|5-20||Possible late effects; possible chromosomal damage.|
|20-100||Temporary reduction in white blood cells.|
|100-200||Mild radiation sickness within a few hours: vomiting, diarrhea, fatigue; reduction in resistance to infection.|
|200-300||Serious radiation sickness effects as in 100-200 rem and hemorrhage; exposure is a Lethal Dose to 10-35% of the population after 30 days (LD 10-35/30).|
|300-400||Serious radiation sickness; also marrow and intestine destruction; LD 50-70/30.|
|400-1000||Acute illness, early death; LD 60-95/30.|
|1000-5000||Acute illness, early death in days; LD 100/10.|