260 Health Physics 158° E 164° E T 442 N pedecm August 2010, Volume 99, Number 2 170° E ! T enna Peecamercma macnn 4 14°N Bikini MO, “4 aff ° : 10° N 0: 4. Ree bovseeetensBeecceeeeeeeeee gaffes + 10°N Ujelang % y P FY e we . ,. gf k & iy aLanaboRen : . . i l T T e i T 14° N eeefovsscecesssecenscesenseeeennaesees fevseccsesseecensscecensnecensaceetenfeccenssceeanaass + 14°N Bikini ~ MS. eh % 10° N g 8: | 4. oo besseeeceeeRvvesemseennes gai + 10°N % . oe maa 4 5 q . k » ¢ , fm oy BN bo ppp: eactnaonsntnsnormact ans ssc astanecanecas Bynes 4 6° N . . L I 158° E 164° E ° L 170° E Fig. 1. Top Panel: HYSPLIT-predicted fallout pattern near Ujelang Atoll resulting from the Dog test. Bottom Panel: HYSPLIT-predicted fallout pattern at Ujelang Atoll resulting from the Item test. importance of accurate upper-air wind data whichlargely influence the trajectory of the radioactive cap cloud that contains over 80% of the radioactivity. There were, however, only a few weather stations in the Marshall Islands during the years of nuclear testing (1946-1958) and they were located at significant distances from the nuclear weapons test sites. Thus, there were limited meteorological data collected that were directly relevant.