What is Cloud Seeding?
Cloud Seeding is an artificial weather modification that aims to change the precipitation that falls from the clouds by dropping the crystal chemicals into the clouds to cause rain whenever and wherever needed. It is also known as rain-making, man-made precipitation enhancement, and so on.
History of Cloud Seeding
The basic idea of Cloud Seeding or weather modification has begun in the 1940s in Schenectady, New York. When American scientist Vince Schaefer, working at General Electric (G.E), dropped crushed dry ice into a super-cooled cloud and watched the world’s first artificial snowfall, after discovering that adding dry ice to the right mix of super-cooled water drops, causes precipitation. Ever since that, Schaefer was known as the Snow Man.
Later Bernie Vonnegut, a college of Schaefer at G.E, searched for chemical materials with a crystallographic structure similar to ice and found that silver iodide particles are similar to dry ice at temperatures below -20C. He then improved Schaefer’s method by using silver iodide instead of dry ice to create artificial snow.
Since then, this method has been used for Cloud Seeding, in creating artificial snow, and also for rain enhancement.
How Cloud Seeding is done?
Cloud Seeding can be done in three methods:
- Static Cloud Seeding: It is done by seeding supercooled clouds with dry ice or silver iodide, which condenses the moisture in the clouds, and further induces snow or rain.
- Dynamic Cloud Seeding: It is done by seeding the clouds, depending on a sequence of events, making the process more complex than Static Cloud Seeding. Because if an error occurs in any of the stages, then the whole process will be affected.
- Hygroscopic Cloud Seeding: This method involves hygroscopic materials like salt particles, which are dispersed into the clouds through explosives. These salt particles upon joining with water grow in size, resulting in faster falls.
Global Impact
After the basic idea of Cloud Seeding is introduced, many companies that are water-dependent, started spending 3 to 5 million dollars per year on these Cloud Seeding projects.
According to the reports of the World Meteorological Organization in 2017, more than 50 countries including India, Russia, Israel, Thailand, Australia, South Africa, China, Caribbean nations, etc. sowed the seeds in the field of artificial weather enhancement.
Despite all the suspicions about Cloud Seeding, China is moving forward with many projects on it, spending about $90 million dollars on weather enhancement projects. The Chinese Government’s goal is to produce about 50 billion cubic meters of rain a year through the projects.
The drought condition in Sri Lanka encouraged the government to take up a project on Cloud Seeding, which only ended up with no result. Despite facing criticism for spending so much money on this project, the government did not back out and continued to move further with the project.
Potential Threats
- The precipitation from the clouds that are seeded with chemicals like silver iodide is a threat to the environment, as silver iodide is proved to be toxic to the aquatic life.
- The Cloud Seeding in certain areas may result in droughts in the areas surrounding them.
- Overdoing the Cloud Seeding would result in an excessive drop in the temperatures, which leads to the weather imbalance
- Without proper measures taken during Cloud Seeding, it results in floods.
Conclusion
Even with all the theories and claims, Scientists from all over the world couldn’t provide answers to the questions that are raised against rain enhancement. Though it would be great if the rain volume gets increased, investing money on a project which has no 100% guarantee, affects the country’s economy.
Agreed, Cloud Seeding is a great weather modification technology, playing God to induce rain and snow whenever and wherever we needed is not a good option. So let us leave nature’s work to nature, instead of trying to modify it manually.