Kind: captions Language: en could this little trailer help save the drought-stricken west by bringing more rain and snow to the region that's what these Engineers think they've parked the trailer up here in the mountains of Colorado in hopes of changing the weather and there's dozens of them just like this in use right now it might all sound like science fiction but it's a weather modification technique called cloud seeding and it was first done successfully as early as the 1940s Colorado some ski towns were cloud seeding as far back as the 70s and it's also been used around the globe China's cloud seeding program reportedly had a plan to make clouds rain before they had a chance to float over the Beijing Olympic Stadium you can find cloud seating from California to North Dakota but how does cloud seeding work to learn more I've come to Colorado to see how seating works up close and personal the night before I arrived the clouds above me were seated we are approaching the location of our cloud seating generator Scott grebling is a water resources engineer for the local Water Conservancy District the locations chosen for these sites have the right elevation and can reach the perfect clouds our district has come to the conclusion that cloud seeding and weather modification is a very safe and very cost effective way of increasing local Water Supplies so how do you see your remote generator Garrett Commons is president of a cloud seeding company that operates hundreds of cloud seeding sites and it sounds like you're terraforming or completely changing the climate of an area but that's not that's not how it works since clouds are basically water vapor the idea is to release particles into the clouds that will attract water making it easier for water droplets or snowflakes to form they get heavier and eventually fall to Earth instead of staying in the sky this Colorado team uses a solution with a chemical called Silver iodide which when burned splits into billions of particles per gram rice is the perfect either clouds eat themselves with ice crystals silver iodide is really the closest and similar structure as eyes so that's why we're using silver iodide here camons activates the flame it contains a silver iodized solution mixed with propane a series of tanks and Regulators manage the pressure and exact flow rate of the silver iodide solution a typical storm system will only drop about 10 percent of its moisture we're hoping that the storm system will drop 10 and a half to 11 and a half percent of its moisture okay but does cloud seeding actually work we would come out with research aircraft and with ground-based Radars and we would basically measure the atmosphere prior to cloud seeding and during cloud seeding The Landmark snowy project set out to discover just that at pretty clever approach a plane flying back and forth dropped chemicals into the clouds when the team studied the resulting precipitation they found it had snowed in a zigzag pattern matching the path of the seating agent's flow could it have all just been a fluke we were in shock or in disbelief and then of course we say okay we saw it one day can we can be repeated they did the same experiment several more times as the wind blew the seating agent the same zigzag line of precipitation appeared which you would never see in a natural snowfall this is revolutionary because we have a hard time quantifying what really comes out from from cloud sailing so at least in some situations cloud seeding can increase precipitation but is up against challenging odds concerned about Reservoir levels over the last 43 years snowpack has only been this low or lower seven times [Music] I'm in a creek snow is crucial to the Rockies because as it gradually melts water runs Downstream replenishing bodies of water for nearby towns that's why Colorado's water conservation board partnered with a Water Conservancy District to share the cost of hiring a cloud-seeding company to seed in the area but is cloud seeding safe silver iodide has been used since the 19th century in photo development and also has an antiseptic in medicine exposure to a large amount of it could even lead to skin and eye irritation high levels of silver iodide in one area could be toxic to organisms in our water and soil for these reasons and others State cloud seeding efforts are reported to federal agencies we want to be conscious we don't really want to put a lot of silver into the atmosphere over the years another big concern about cloud seeding has been that it could cause too much precipitation such as this massive flood in the small town in the UK which destroyed homes and killed more than 30 people while circumstantial some linked it to a nearby cloud seeding program s actually have to play by the rules as soon as they have a certain snow depth they stop seeding and in order to prevent floods today canvas's company has hundreds of seating sites and across the globe several other nations are testing the technology in fact nearly every meteorologist I spoke with told me to get ready as they expect cloud seeding once a big question mark to increase in frequency as for the potential to impact drought it may be a long time before scientists know for sure even if widely used it's still difficult to quantify exactly how much additional precipitation comes from seeding a cloud we all know about the greenhouse effect but how many of us understand why it happens our friends have reactions uncover what's so unique about carbon dioxide that has allowed it to transform our entire planet check out the link in the description and let them know Nova sent you [Music] foreign