Cloud seeding 101

Clouds are made up of tiny water droplets. For precipitation (such as rain or snow) to happen, you need particles of dust or salt in the atmosphere, a constituent scientists call condensation nuclei.

Cloud seeding is a type of weathermodification technology that increases a cloud’s ability to produce rain or snow by artificially adding condensation nuclei to the atmosphere. Cloud seeding mainly happens using ground-based generators or aircraft. The former are usually positioned on elevated areas such as mountain tops, from where flares loaded with salt crystals are shot into the sky.

Scientists say that cloud-seeding operations can enhance rainfall by as much as 35 per cent in a clear atmosphere, and up to 15 per cent in a turbid atmosphere. However, in spite of these reports, there’s still much debate around the topic of whether cloud seeding actually works. There’s no way to tell if the ensuing rain is the direct result of the cloud-seeding mission.

New technologies, incorporating artificial intelligence and machine learning, are being used in combination with more powerful computers and instruments to help understand the potential of cloud seeding. According to Dr Deon Terblanche, an atmospheric scientist who is also the vice chair of the World Meteorological Organization, innovative research will help guide weather augmentation going forward, and will ultimately secure our future water. ‘We will reach a stage in a few decades where we have much better control over the weather,’ he says. ‘We have to, because it’s one of the biggest threats we are facing.’

The primary goal of cloud seeding is rain enhancement, as water scarcity is a crucial concern for the future.