What is cloud seeding?

Cloud seeding is when tiny particles are added to clouds to help them produce more precipitation.

Clouds form from tiny, light water droplets or ice crystals. As they bump into each other, they merge to form larger drops. The water droplets fall as rain when they are too heavy to be supported by upward moving air currents.

Cloud seeding involves adding particles that act like seeds for water droplets to hang onto, encouraging clouds to form faster. The particles are usually released from aeroplanes.

Imagine a handful of small light balls. If something sticky is in the middle, they will stick together to form a bigger ball. Cloud seeding provides the sticky centre.

Which chemicals are added to clouds for cloud seeding

Silver iodide – this has a structure similar to ice, so water droplets attach to it more easily.

Dry ice – this is VERY cold and so freezes water droplets

Salt – attracts water, helping droplets grow.

Is cloud seeding safe?

The safety of cloud seeding is a complex issue and the subject of ongoing debate.

Chemicals used

Some people are concerned about silver iodide building up in the environment and possibly affecting aquatic life. We also don’t have any information about the long term effects and potential health risks.

Other people argue that the concentration of silver iodide used is low and poses minimal risk to human health and the environment.

Environmental Impacts

Some people are concerned that the chemicals used could build up in water supplies and soil over time.

There are concerns about disrupting natural weather patterns and that introducing precipitation in one area could lead to drought elsewhere.

Increased rainfall could damage crops and disrupt finely balanced ecosystems.

Excess rain could lead to flooding and landslides.

Overall, much more research is needed to fully understand the long term consequences of cloud seeding.

Find out more

Make a rain cloud in a jar.

Monitor rainfall with a DIY rain gauge.

Find out where rain comes from.

Cloud seeding in the news

Cloud seeding and the Dubai floods – 2024

Why cloud seeding cannot make or control the weather – ABC News

References

Huseynli, O. (2024, April 18). Cloud seeding: Advantages and disadvantages | Earth.Org. Earth.Org. https://earth.org/unleashing-the-power-of-cloud-seeding-navigating-potential-and-pitfalls/

Last Updated on April 24, 2025 by Emma Vanstone