REPORTS OF RAIN DURING BRAVO FALLOUT
Transcripts of post-cetonation briefings suggest that seif-induced rainout
oevurred for a short time after Bravo was detonated.
The crew of the Japanese
fishing ship, No. 5 Fukura Maru (Lucky Dragon), while fishing downwind just outsice
the exclusion zone, noted that the initial fallout on their ship was accompanied by "a
light
rain or drizzle.t 7)
It
is unlikely that
this was a continuation of the
self-induced rainout, some two or more hours after Bravo's cetonation; it was
orobabdly a natural rain system superimposed on the debris cloud.
Another report of rain during Bravo fallout was made by a group of Rongelap
natives after evacuation.
(8] They lived in Rongelap Village, on the southern part
of Rongelap Atoll, and stated that it "rained a little" during the afternoon of March
Ist.
Another interview with an American Air Foree radio operator (8] who had
2een on Rongerik Atoll prior to evacuation disclosed that "rain commenced about
2100 [LST] and continued for 30 minutes."
Finally, the S. S. Roque, owned by Micronesian Lines, left Kwajalein at 0945
LST and arrived at Utirik at about noon on March 2, 1954.
The ship left Utirik
(apparently a few days later) and arrive at Majuro Atoll on March 7. A radiological
survey at Majuro disclosed radiation readings of 10 to 30 mr/h on March 7.
The
ship's captain mentioned that he had encountered rain squalls during his voyage, but
was not specific about where or when.
It appears certain that the S. S. Roque
encountered Bravo fallout, possioly accompanied by rain showers, either while
approaching or while in harbor at Utirik. If 10 mr/h are "grown back" to five or six
davs earlier (when the Bravo debris cloud passed near Utirik), the dose rate is
estimated at about 100 mr/h.