In the skies of the United States, aircraft sprinkle silver iodide to make it fall even more

Aircraft with missiles to pollinate clouds / Wikipedia

A technique known since the 1940s to alter the structure of clouds and increase precipitation, is experiencing a strong recovery in the United States, where drought is increasing dramatically. This practice, called rain clouds (or rain clouds in English), dispersion exploits to draw out chemicals such as silver iodide, a compound with a structure that catalyzes the freezing water vapor reaction. In other words, to increase the amount of snowfall in certain areas, and thus to obtain additional water reserves in the spring and summer, the transiting clouds are stimulated over some areas of the USA by planting chemical compounds inside them by the use of aircraft transportation Rockets loaded with silver iodide.

Just last winter, in the state of Wyomingwhere is the rain clouds Funded under a federal program, 28 flight missions were carried out, not without controversy over the safety and environmental impact of silver iodide, whose prolonged exposure can cause temporary disability but not chronic damage. However, several studies over the years have shown the low toxicity of silver and its derivatives, possibly in relation to the amount dispersed in clouds, 100 times lower than industrial emissions in many parts of the world. On the other hand, accumulation in soil and vegetation has not been adequately studied, just as it is not clear whether this practice You just shift the spatial distribution Precipitation rather than causing more in general.

Currently, reports CNNThe rain clouds It is used in about 50 countries, but many climate scientists remain skeptical about the efficacy of this technique as well as the time and effort spent trying to manipulate the climate. Also noted is Daniel Swain, a climate scientist at the University of California, Los Angeles Difficulty designing scientific experiments To test technical efficiency. “How do we know how much rain would have fallen if the seeds had not been planted? Swain said. Distinguishing rainfall due to IVF is really uncontrollable“.

According to Swain, experiments rain clouds They typically deal with a narrow set of parameters, taking into account weather conditions including cloud cover, time of day and location. Moreover, I rapid climate change Add another layer to the list of variables, as with gradual global warming, weather patterns and clouds are constantly evolving, often in uncontrollable ways.

at Experiment – Experiment Conducted in 2017 over Payette Basin, Idaho, where silver iodide was planted in three rain cloudsselect scholars.Unmistakable dispersal patterns“In cloud banks that do not normally produce precipitation but, once processed, form ice crystals that reflect the flight pattern. Therefore, the scientists measured the amount of precipitation generated, using radar models and mathematics, although it has remained Various doubts About the real possibility that this technology is a tangible solution to drought, also reported by researchers involved in the research, including Sarah Tessendorf, a scientist at the National Center for Atmospheric Research in Boulder, Colorado. The expert said that this practice can “Over the years it helps to increase storage levels in the reservoirs but the amount of precipitation generated by cloud seeding – up to 10% Not enough at all to solve the problem“.

In general, part of the scientific community also points out that methods that require deploying fossil-fueled aircraft to disperse silver iodide into clouds are inconsistent with the climate goal of Reduce emissions from fossil fuels. However, according to Tessendorf, it would be easy to pay for improving technology: “The number of aircraft and the duration of these flights to conduct cloud seeding, as well as the programs that currently do so, pale in comparison to the number of commercial and air flights we have in the skies around the world at the moment. – says the researcher -. To me, it’s a drop in the bucket of extra fossil fuels being burned, but that doesn’t mean there’s no room for improvement in order to have a cleaner process.“.