The good people of Toowoomba, Australia, a town of about 90,000 that sits atop the Great Dividing Range in southeast Queensland, have a branding problem on their hands. Residents of the nation's "Garden City" have not been able to use their sprinklers for nearly three years. Handheld hoses got the kibosh two years ago, and in 2006, watering the lawn by bucket was also banned.
Why? Toowoomba's residents are slowly running out of water, and have been for the last 15 years, along with nearly everyone else in this corner of eastern Australia. It's the region's worst and longest-lasting drought in over a century, and dead flower beds and brown football fields are the least of their worries. Toowoomba was the go-to city for a large rural area, including nearby Darling Downs, a fertile farmland, until the rain went away and never came back. "We've been in water restriction in Toowoomba since 1992," says Dianne Thorley, the city's mayor of eight years. "Australia [is] drying up, a little bit like a dried apple."
Toowoomba and its environs might be in luck. This week, scientists in the area got one step closer to launching what could be the world's most advanced experiment in rainmaking or, as it's known in weather circles, cloud seeding. It's the practice of injecting clouds with a foreign substance, usually silver iodide, salt or dry ice, to make the the cloud's water or ice particles bigger and yield more rain. The technique has been used in different parts of the world for more than 60 years, with varying success. But the improvement of weather technology and an enduring human interest in trying to play with the sky has kept the practice afloat during times of hard skepticism and dwindling funds. Now this thirsty corner of Australia could be on the path to prove, once and for all, whether we can help make rain or not.
The trial couldn't happen in a place that needs it more. Queensland's government has budgeted 7.6 million Australian dollars ($6.7 million U.S.) in public money into the four-year, multipartner experiment, part of a larger initiative to fight the crushing drought, including a desalination plant and a controversial program to recycle waste into drinking water. "We're in uncharted territory as far as rainfall goes," says Craig Wallace, the state's Natural Resources and Water Minister. Wallace acknowledges that going out on a limb with cloud seeding which still has its naysayers in the scientific community may raise some eyebrows. "You'll always get skeptics, but we owe it to the people of Queensland to try everything we can."
Cloud seeding was invented in 1946 by Bernard Vonnegut, older brother to essayist and novelist Kurt. Since then, it has enjoyed a colorful history. Countries around the world quickly adopted the technology, and over the three decades following its introduction, the U.S. spent many millions of dollars a year on weather modification. It was even used during the Vietnam War to increase rainfall on the Ho Chi Minh trail to hamper supply movement, until word got out and the U.S. agreed not to play with the weather while making war. In the 1970s, the science of cloud seeding acquired a whiff of the snake oil, as disreputable private companies tried hawking it to desperate, drought-ridden communities. And by the following decade, it had fallen out of favor (its use in Vietnam, which reminded some people of Agent Orange, probably didn't help much), and funding fell off with it.
According to Roelof Bruintjes, a cloud seeding expert with the U.S. National Center for Atmospheric Research, what's different about the Queensland project is that for the first time, scientists will be able to take full advantage of a simple premise: some clouds are better for seeding than others. Up to now, the right weather-measuring tools have never been in the right program at the right time. Starting in November, they will be. A project staff of about 30 will use a recently installed CP2 Doppler radar to analyze what's happening in the regions' clouds before, during and after silver iodide "seeds" are sprayed into them from planes. Working in tandem with other ground radars and forecasting equipment, the technology will be able to take a 3-D read of the atmosphere similar to a body scan. Not only will this mean better information about when conditions are right to send the seeding planes, but they will enable scientists to "watch" how the water and ice particles in the cloud are affected by the chemical. "This has not been done in any program anywhere in the world before," Bruintjes says. "Once we know what nature is producing in a specific region, we can determine how we can optimize this."
The farmers around Toowoomba already know what nature is producing in their specific region: zilch. More specifically, zilch, with no end in sight and it has pushed many local farmers past the point of coping. "The rural communities have suffered the most," says Toowoomba Mayor Thorley. "When things get really bad, people get depressed and anxious about what's happening. It makes it difficult for families." In the 1990s, an outreach group called the Bush Connection was established to ease the the social impact of the drought: alcoholism, domestic violence and suicide.
Whether or not the Toowoomba project brings rain, it is at least offering an oasis of hope for the people of southeast Queensland. Like the state, Toowoomba has explored several options to get more water to people, from tapping into natural underground aquifers to pumping water some 700 meters up the mountainside. Thorley estimates her city has invested 600 million Australian dollars in its water infrastructure, and thinks for the state to shell out $7.6 million on a cloud seeding experiment is a worthwhile risk. "If it proves to do something, then it has to have some benefit," she says. "If we're seeing such weird weather if we're going to have to pump water all over Australia via huge pipelines wouldn't it be wiser to find another way?" she asks. "It would be worth a go."