STRATOSPHERIC DISTRIBUTION
OF NUCLEAR DEBRIS
IN 1962, 1963, AND 1964
HERBERT W. FEELY and FERNANDO BAZAN
Isotopes, Inc., Westwood, New Jersey
ABSTRACT
An estimate may be made of the stratospheric distribution of nuclear
debris by using a combination of data from the balloon sampling pro-
gram and the WU-2 aircraft sampling program. The stratospheric "Sr
distributions from January 1962 through May 1964 have been estimated,
and from them the stratospheric burdens (ranging from 0.9 Mc before
the 1961 U.S.S.R. tests to perhaps over 7 Mc hy early 1963 and then
falling to about 4.4 Mc in late 1963) have been calculated.
The observed vertical distributions of "Sr and of certain tracer
nuclides, such as “Mn, indicate that little debris from the pre-1962
U.S.S.R. test series and even from events of very high yield had stabi-
lized at altitudes above 70,000 ft in the polar stratosphere and that only
a small fraction of the debris from the 1962 U.S.S.R. test series stabilized above that altitude.
Relatively little debris from either the 1961 U.S.5.R. tests or the
1962 United States tests reached the southern polar stratosphere during
1962, During 1963, however, large quantities of debris from the 1961
and 1962 test series did reach that region, as revealed by sampling in
the vicinity of Australia. This debris appeared in the 80,000- to
90,000-ft layer at Mildura during June to August 1963 (the southernhemisphere winter), and it was found by both balloon and WU-2
Sampling in the region below 80,000 ft from September through No-
vember 1963 (the southern-hemisphere spring). The rate of southward
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