Bf. Ryan et Wd. King, A CRITICAL-REVIEW OF THE AUSTRALIAN EXPERIENCE IN-CLOUD SEEDING, Bulletin of the American Meteorological Society, 78(2), 1997, pp. 239-254
From 1947 to 1994 a number of cloud-seeding experiments were done in A
ustralia based on the static cloud-seeding hypothesis. A critical anal
ysis of these successive cloud-seeding experiments, coupled with micro
physical observations of the clouds, showed that the static cloud-seed
ing hypothesis is not effective in enhancing winter rainfall in the pl
ains area of Australia. However, there is evidence to suggest that clo
ud seeding is effective for limited meteorological conditions in strat
iform clouds undergoing orographic uplift. In particular, two successi
ve experiments in Tasmania show strong statistical evidence for rainfa
ll enhancement when cloud-top temperatures are between -10 degrees and
-12 degrees C in a southwesterly stream. The evidence for similar eff
ects on the Australian mainland is more controversial. In the summer r
ainfall regions of northern Australia, the extreme rainfall variabilit
y makes it impossible to design a statistical experiment that can to b
e evaluated in a reasonable time using currently available techniques.
Rainfall enhancement in these regions remains inconclusive.