RADIOACTIVITY IN PRECIPITATION: CASE STUDIES
FROM THE 1964 SPRING SEASON
SAMUEL J, HALL
University of Oklahoma, Norman, Oklahoma
ABSTRACT
Four case studies are presented of convective storms in which time
samples. of rainfall were collected. The profiles obtained from these
collections are analyzed showing time variations of total betaradioactivity content, rainfall rate, and ratio of particulate to dissolved
beta activity, These data, with their respective radar data analyses,
indicate the temporal changes of beta concentration as well as areal
distributions in convective storms, For mature storms a minimum of
beta concentration is associated with maximum rainfall rates. For
dissipating storms a maximum of beta concentration is associated with
maximum rainfall rates.
INTRODUCTION
During the springtime maximum of severe convective storms in
Oklahoma, data were collected for storms of varying nature and
intensity. Case studies of four storm situations of differing natures
and stages of development are presented. One case, occurring on
April 23, 1964, was an isolated cell, whereas the other three cases,
on April 17, May 9, and May 10, were squall lines, The squall-line
storms of May 9 and May 10 were parts of the same synoptic situation;
therefore they are investigated and compared accordingly.
The observation and rainfall-collection program is discussed
elsewhere,* but I will mention here that data were taken for storms
*See paper by Walter J. Saucier, Samuel J. Hall, and Robert Y. Nelson,
this volume.
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