Cloud seeding, although decades old, is still controversial in the weather community, mostly because it has been hard to prove that it does very much. No one reports the type of flooding that on Tuesday doused the UAE, which often deploys the technology in an attempt to squeeze every drop of moisture from a sky that usually gives less than 4 or 5 inches (10 to 13 centimeters) of rain a year. "It's most certainly not cloud seeding," said private meteorologist Ryan Maue, former chief scientist at the U.S. National Oceanic and Atmospheric Administration. "If that occurred with cloud seeding, they'd have water all the time. You can't create rain out of thin air per se and get 6 inches of water. That's akin to perpetual motion technology." Meteorologists and climate scientists said the extreme rainfall is akin to what the world expects with human-caused climate change, and one way to know for certain that it was not caused by tinkering with clouds is that it was forecast days in advance. Atmospheric science researcher Tomer Burg pointed to computer models that six days earlier forecast several inches of rain—the typical amount for an entire year in the UAE. Three low-pressure systems formed a train of storms slowly moving along the jet stream—the river of air that moves weather systems—toward the Persian Gulf, said University of Pennsylvania climate scientist Michael Mann. Blaming cloud seeding ignores the forecasts and the cause, he said. Many of the people pointing to cloud seeding are also climate change deniers who are trying to divert attention from what's really happening, Mann and other scientists said. "When we talk about heavy rainfall, we need to talk about climate change. Focusing on cloud seeding is misleading," said Imperial College of London climate scientist Friederike Otto, who heads a team that does rapid attribution of weather extremes to see if they were caused by global warming or not. "Rainfall is... |