Cloud seeding, will it save us from drought? – OpEd
By Dr. Michael A. Bengwayan, Fellow of Echoing Green Foundation of New York City
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The absence or shortage of rainfall has been of increasing concern since the 1970s. One of the most popular weather modification discoveries is cloud seeding. This method initiates rainfall by targeting clouds. Seeding can occur from an aircraft or from the ground with silver iodide, dry ice and salt.
But if cloud seeding works, why isn’t it implemented in many of the world’s regions that are water scarce? “Simple, there aren’t enough clouds or there is unfavorable cloud formation. Cloud seeding cannot happen without clouds”, a scientist from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), said.
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A World Meteorological Organization (WMO) primer explains that not all types of cloud favor cloud seeding. The most likely to allow artificial rainmaking are Cumulus Clouds, a cauliflower-like type of clouds.
The cloud forms from updrafts of warm, moist air into an atmosphere that is unstable. Intense daytime heating of the near-surface layer of air, or a wedge of cold air moving across the state (as a cold front), usually triggers the formation of convective clouds.
Normally, a small percentage of cumulus clouds are needed to yield an appreciable amount of rainfall. But these clouds that do produce rainwater are often inefficient.
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