Rain made from Saharan dust
The rain-making power of Saharan dust may soon be harnessed to bring vital rain to drought-stricken south-eastern Turkey.
Radio Netherlands reports that the dust which blows from the hot dry Saharan desert is particularly good for improving snow and rainfall. This apparent paradox was discovered recently when Professor Cemal Saydam of the Turkish science institution, TUBI-TAK, used Saharan dust in the laboratory to make ice particles.
It has been known for some time that dust and water droplets can interact to form snow crystals. When dust in the atmosphere encounters a cloud, ice crystals will form and cause rain or snow to fall if the conditions are right.
Saharan dust has special properties when it comes to rain-making, said Professor Ogurcan Oraltay, a colleague of Professor Saydam's.
"If we use Saharan dust to grow ice crystals [in the laboratory], it's about 50 per cent more effective compared to ordinary dust," he said. He points out that the ice crystals formed using Sahran dust are around four times larger than normal.
Snow measurements taken across Turkey show that the more dust is in the air, the more snow falls. Conversely, the presence of snow usually correlates with a cloud of dust recently blown from the Sahara.
Researchers suspect the dust's high organic and iron content are the key to its super rainmaking qualities and they plan to seed clouds over Turkey with Saharan dust spread from an aeroplane or a hot air balloon.
To avoid the possibility of flash flooding, the research team is currently waiting for cold weather to ensure any precipitation created will fall as snow.