evidence: Washington, DC— Well-understood physical and chemical processes can easily explain the alleged evidence of a secret, large-scale atmospheric spraying program, commonly referred to as "chemtrails" or "covert geoengineering," concludes a new study from Carnegie Science, University of California Irvine, and the nonprofit organization Near Zero. [...] The authors of this study, including Carnegie’s Ken Caldeira, conducted a survey of the world’s leading atmospheric scientists, who categorically rejected the existence of a secret spraying program. The team’s findings, published by Environmental Research Letters, are based on a survey of two groups of experts: atmospheric chemists who specialize in condensation trails and geochemists working on atmospheric deposition of dust and pollution. [...] "Despite the persistence of erroneous theories about atmospheric chemical spraying programs, until now there were no peer-reviewed academic studies showing that what some people think are ‘chemtrails’ are just ordinary contrails, which are becoming more abundant as air travel expands. Also, it is possible that climate change is causing contrails to persist for longer periods than they used to." Caldeira said. "I felt it was important to definitively show what real experts in contrails and aerosols think. We might not convince die-hard believers that their beloved secret spraying program is just a paranoid fantasy, but hopefully their friends will accept the facts."