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Golden State Weather Warriors
California, parched by drought and shrinking mountain snowpacks, hopes cloudseeding (yes, cloudseeding) could help quench its driest year on record.

A small flurry of “who knew?” news reports accompanied last week’s opening of California’s annual cloudseeding season. The Sacramento Bee, in a widely distributed feature, outlined active weather modification projects in 15 California watersheds, citing a state report estimating that cloudseeding adds 400,000 acre-feet of water annually to California’s reserves—enough to supply three out of every ten households in the Bay Area for a year. The San Jose Mercury News noted that water managers across the state fear the impacts of drought, and with good reason: San Francisco has just experienced its driest year on record. Grist quickly weighed in, opining that cloudseeding was “certainly not a real fix for climate change.”

Perhaps not, but Jeff Tilley, director of weather modification at the Desert Research Institute, welcomed the public’s apparent embrace of cloudseeding as a weapon in the war on drought, declaring: “The message is starting to sink in that this is a cost-effective tool.”

If so, the sinking-in has been a long time coming. As I reported in the Fall 2013 issue of OnEarth, the practice of seeding clouds with silver iodide to increase rain or snowfall was pioneered by GE in 1946 and has been in use ever since, particularly in the arid West. Utilities in California started seeding high Sierra watersheds in 1948. Today there are weather modification programs operating in ten Western states, including hail reduction efforts in North Dakota, rain enhancement in Texas and Kansas, and snowpack augmentation in Wyoming, Idaho, Colorado, Utah, and Nevada.

But California remains perhaps the best example of how cloudseeding can potentially help fight droughts. Not only is the state perpetually in need of more water, but its geography and climate come together to make cloudseeding over the Sierra Nevada especially effective. Moisture-laden clouds roll off the Pacific and hang up on the Sierra’s peaks. Those clouds represent an untapped water resource if they don’t precipitate on their own.

Contrary to science fiction and conspiracy theories, rainmakers cannot “make rain.” What they can do is help existing clouds precipitate. Clouds do not always release their stored water vapor—in fact the majority of it never falls, partly because water droplets in clouds are often supercooled, meaning they remain liquid even at temperatures well below freezing. Without forming ice crystals, they are too tiny to fall. “Rainmaking” provides a nucleus to which the cloud’s supercooled water droplets can adhere until they grow heavy enough to fall to the ground as rain or snow. Silver iodide, with a crystalline structure similar to that of water, is most commonly used; it is aerosolized and dispersed via burners on the ground or mounted on airplanes.

Weather modifiers call what they do “precipitation enhancement,” and declare that it bolsters cloud efficiency—sometimes “downstream” as well as in the target area. It does not, as many fear, rob Peter to pay Paul, though public understanding of that fact has lagged behind the science from the beginning. (As reader comments on some of the articles noted above demonstrate, there’s no shortage of ill-informed paranoia about weather modification.)

Immediately after inventing the process in 1946, GE scientists teamed up with the military on Project Cirrus, an ambitious series of cloudseeding experiments aimed at ending droughts, controlling snowfall (more for ski resorts, less for cities), preventing forest fires, averting hail, and even busting hurricanes. The popular press, caught up in the excitement, announced the dawn of a new era of weather control. Man was finally going to do something about the weather.

That never happened. Concerned about legal ramifications and unclear profit potential, GE got out of weather control in the early fifties, and although a series of government and private experiments ensued, the irrational exuberance of weather modification’s early years caused the shadow of junk science to blight it for decades. By the eighties, interest had died down so much that even the U.S. Bureau of Reclamation—whose motto is “Managing Water in the West”—largely ceased work in the field. Rainmakers point out that this lack of enthusiasm coincided with an exceptionally wet period in the United States. They have a saying for this phenomenon: “Interest in cloudseeding is soluble in rainwater.”

There’s no shortage of ill-informed paranoia about weather modification.

Today, however, as climate uncertainty grows, the West languishes in an epic drought, and wildfires rage, interest in cloudseeding is resurgent. A rigorous study being done in Wyoming, spearheaded by the National Center for Atmospheric Research, will publish its results in summer 2014. At the annual meeting of the Weather Modification Association this year, a scientist on the study reported that they expect to report precipitation increases of around 10 percent, with 95-percent confidence, in seeded clouds. That’s not quite a climate-control bonanza. But it is significant to states that depend heavily on water stored in mountain snowpacks. And for states making hydropower from run-off, 10 percent more water through their turbines adds up to real money.

Weather modification strikes some people as creepy, a form of tampering with nature. But in a state where hydro projects have already dammed and diverted all the state’s major rivers, turned a breathtaking valley into a reservoir, made a dust bowl of a former inland sea, and—by accident—created the state’s largest lake, wringing a little extra precipitation from the winter clouds seems minor in comparison.

Cloudseeding will not, of course, solve California’s water problems. What it should do is draw attention to the fact that our rapid development of the West, with no regard for the drain on its natural resources, is already forcing us to take extreme measures—and things are only getting worse.

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image of Ginger Strand
Ginger Strand is the author of a novel, Flight, and two books of nonfiction: Inventing Niagara: Beauty, Power, and Lies and Killer on the Road: Violence and the American Interstate. She writes for a variety of magazines, including Harper’s, Wired, and Orion, where she is a contributing editor. MORE STORIES ➔
Comments (3)
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"Tell the PUC: No new dirty gas plants! Every year, more than 70,000 California kids are rushed to the hospital because they can’t breathe, due to air pollution in Calfiornia. Unfortunately the Governor and the Public Utilities Commission (PUC) are considering huge new gas-fired power plants to replace the San Onofre Nuclear Generating Station. Dirty gas plants will make our air worse and just aren't needed. We can't sit by and let our air get dirtier and our kids even sicker, when we've got cheaper, cleaner, safer options like Renewable Energy." Sierra Club California, there is enough Residential Solar to power 2.25 San Onofres, couple that with a Residential and Commercial Feed in Tariff and we can solve some of these environmental and electrical generating problems. The Southwest is in the midst of a record drought, some 14 years in the making, which means the water supply for many Western states - California, Arizona, Utah, Nevada - is drying up. Last month the Bureau of Reclamation announced they're cutting the flow of water into Lake Mead, which has already lost 100 feet of water since the drought began. What happens if the Southwest drought does not end soon? Will we keep using 3 to 6 million gallons of Clean Water per Fracked well, to extract natural gas? This petition will ask the California Regulators and Law makers to allocate Renewable Portfolio Standards to Ca. Home Owners for a Residential Feed in Tariff, the RPS is the allocation method that is used to set aside a certain percentage of electrical generation for Renewable Energy in the the State. The State of California has mandated that 33% of its Energy come from Renewable Energy by 2020. The state currently produces about 71% of the electricity it consumes, while it imports 8% from the Pacific Northwest and 21% from the Southwest. This is how we generate our electricity in 2011, natural gas was burned to make 45.3% of electrical power generated in-state. Nuclear power from Diablo Canyon in San Luis Obispo County accounted for 9.15%, large hydropower 18.3%, Renewable 16.6% and coal 1.6%. There is 9% missing from San Onofre and with the current South Western drought, how long before the 18.3% hydro will be effected? Another generator of power that jumps out is natural gas, 45.3%, that is a lot of Fracked Wells poisoning our ground water, 3 to 6 million gallons of water are used per well. If Fracking is safe why did Vice Pres Cheney lobby and win Executive, Congressional, and Judicial exemptions from: Clean Water Act. Safe Drinking Water. Act Clean Air Act. Resource Conservation and Recovery Act. Emergency Planning Community Right to Know Act. National Environmental Policy Act. "Americans should not have to accept unsafe drinking water just because natural gas is cheaper than Coal. the Industry has used its political power to escape accountability, leaving the American people unprotected, and no Industry can claim to be part of the solution if it supports exemptions from the basic Laws designed to ensure that we have Clean Water and Clean Air" Natural Resources Defense Council. We have to change how we generate our electricity, with are current drought conditions and using our pure clean water for Fracking, there has to be a better way to generate electricity, and there is, a proven stimulating policy. The Feed in Tariff is a policy mechanism designed to accelerate investment in Renewable Energy, the California FiT allows eligible customers generators to enter into 10- 15- 20- year contracts with their utility company to sell the electricity produced by renewable energy, and guarantees that anyone who generates electricity from R E source, whether Homeowner, small business, or large utility, is able to sell that electricity. It is mandated by the State to produce 33% R E by 2020. FIT policies can be implemented to support all renewable technologies including: Wind Photovoltaics (PV) Solar thermal Geothermal Biogas Biomass Fuel cells Tidal and wave power. There is currently 3 utilities using a Commercial Feed in Tariff in California Counties, Los Angeles, Palo Alto, and Sacramento, are paying their businesses 17 cents per kilowatt hour for the Renewable Energy they generate. We can get our Law makers and Regulators to implement a Residential Feed in Tariff, to help us weather Global Warming, insulate our communities from grid failures, generate a fair revenue stream for the Homeowners and protect our Water. The 17 cents per kilowatt hour allows the Commercial Business owner and the Utility to make a profit. Commercial Ca. rates are 17 - 24 cents per kilowatt hour. Implementing a Residential Feed in Tariff at 13 cents per kilowatt hour for the first 2,300 MW, and then allow no more than -3 cents reduction in kilowatts per hour, for what ever the first tier Residential rate is in you area, for the remaining capacity of Residential Solar . A game changer for the Voting, Tax Paying Home Owner and a Fair Profit for The Utility, a win for our Children, Utilities, and Our Planet. We also need to change a current law, California law does not allow Homeowners to oversize their Renewable Energy systems. Campaign to allow Californian residents to sell electricity obtained by renewable energy for a fair pro-business market price. Will you read, sign, and share this petition?
Yeah! Right! (Two positives=negative!) GE also designed the three Fukushima, JP power plants that have now melted down and are spewing intense radiation into our environment. For just weapons grade 239-plutonium in reactor 3's MOX fuel, wherever that core has gone, this won't be safe for 241,000 years (10 half-lives), even if the contamination were to stop today, there being no end in sight, and that is just one of the less, long-lived isoptopes being spewed from the MOX fuel in one of three melted down reactors, wherever those other nuclear core are! Nuclear power is safe? Cheap? Hogwash, not when one considers the costs of monitoring wastes, and their health consequences! Tell that to the Japanese who are, for all practical purposes, forever banned from their $1M/acre property, and probably without relief from their mortgages. You aren't robbing Peter to pay Paul? Bull! Water that falls in California is not carried by the winds/jet stream to locations farther east! Check the jet stream and ocean currents! Southern California already taps into the downhill water as far away as Colorado to feed its ravenous consumption and waste of water. Count the private swimming pools in California and....Grunt! Grunt! I won't be buying California unlabeld-GMO produce...ever!! Signed, Lives without indoor plumbing near the Gasbuggy experiment (Operation Plowshare)! Galen P.S. Is YOUR natural gas contaminated with radiation? Did you know they are putting radioisotopes in fracking operations to trace results? Read the congressional reports about the 750 chemicals, including carcinogenic and radioactive ones, that have been or are being used in fracking!
Crop-dusting the state with sliver iodide? Really? The solution is more surface water storage in California. Yes, sorry, dams & reservoirs. Capturing more of the water that lands in California NATRURALLY rather than sending it roaring out to sea would dilute many if not all of the State's current water problems. Wildlife would benefit, salts and pollutants would become more dilute and the state would return to being a garden than becoming a toxic dessert. Water conservation begins in lakes, ponds & streams, not water meters & misting shower heads.