Did cloud seeding cause Dubai flooding? What to know about the science
The United Arab Emirates (UAE) capital of Dubai remains flooded after a deluge of rain that fell earlier this week.
By Tuesday, 142 millimetres had fallen in about 48 hours – which is about 50 per cent more than the annual total precipitation.
The Dubai International Airport is the world’s busiest for international travel and arrivals remain halted. Officials estimate it will take days to return to normal.
Several unconfirmed reports suggested cloud seeding could have played a role in the flood. But what is cloud seeding, how is it used, and is there a more likely reason for the deluge?
Clouds are made of suspended water vapour. Rain occurs when that water vapour comes together around a very small particle, called a nuclei, to form drops. This can happen around ice particles but other substances, like silver iodide, attract vapour more than ice.
Humans can spray the substance from planes or drones, or project particles from the ground using cannons, to infuse the clouds.
“When it’s in a cloud, then water molecules will see that surface and think that it’s like ice,” Canada Research Chair in Atmospheric Science Rachel Chang told Global News.
“(Water will) start condensing or freezing on to that silver iodide particle and then basically build ice up,” she said.
Chang said the ice crystals can grow rapidly until they’re large enough to fall as snow. If the temperature is warm enough, they’ll turn to rain.
Cloud seeding was invented in the 1940s and became popular in the United States in the 1960s. Dozens of countries, including Canada, use the method, sometimes to fight forest fires or drought or to create snowor to limit the size of potentially damaging hail.
The U.S. Bureau of Reclamation spent $2.4 million last year on
Read more on globalnews.ca
