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SESSION IIIB DISCUSSION
more and that a jet-stream core can be traced from Washington back
across the sparse-data areas of the Pacific and Asia to a test site
over Russia?
GUDIKSEN: I am not stating that mass is conserved for this time
length but that at least some of the debris that is injected into the jet
stream at one point will be carried for long distances; however, a large
part of this debris will be lost along the way. About the second part of
your question, the Weather Bureau was able to produce rough trajec-
tories for a jet stream from Washington back across the Pacific.
MACHTA: Dr. Volchok, did you study the seasonal variations during the year 1960?
VOLCHOK: No.
MACHTA: This year is of special consequence because the seasonal variation was more evident in the southern hemisphere than in
other years. Furthermore, both the tropospheric and stratospheric
concentrations of the two hemispheres were about equal.
WALLACE: Dr. Volchok, do you have any explanation for the fact
that the spring maximums of radioactivity in tropospheric air in the
two hemispheres occur four months apart instead of six months apart?
VOLCHOK: Notright off. I think it is very interesting.
HERDE: I would like to hear again, I believe I have heard at one
time, the explanation of the origin of "Be, manganese, and some of the
other nonfission products. I think it very appropriate to identify the
origin of those that are relatively new.
REITER: Dr. Gustafson, would you like to comment on that?
GUSTAFSON: Beryllium-7 is actually produced by fissioning or
Spallation of oxygen and nitrogen by energetic cosmic rays by both
primary protons and secondary mesons. The amount of "Be produced
per gram of air increases with altitude up to at least 70,000 ft and
also with increasing geomagnetic latitude. There is a modest produc-
tion of this radionuclide in the troposphere, but its primary source is
in the low or middle stratosphere. (Editor’s note: There was further
discussion on this subject during the general discussion.]|
JONES (Illinois State Water Survey): Mr. Hall, how did you measure the duration of each sample?
HALL: By relating the rainfall traces on the rain-gauge charts,
the total amount of rainfall, and the number of samples, we were able
to estimate quite closely the time and the duration of each rain sample.
REITER: I have some doubts whether convective systems penetrating into the stratosphere, such as the ones you mentioned penetrat-