At the world's first major geoengineering conference, two separate scientists put forward proposals to use lasers to modify the Earth's climate and fight global warming, from space. One suggested that a satellite equipped with a high-powered laser could grow clouds in the atmosphere below; the other proposed lasers that would blast greenhouse gases from orbit to effectively erase the agents of climate change. — Vice Motherboard
For those unaware, geoengineering, in this context, refers to large-scale, intentional interventions in the Earth's climate, particularly towards the end of fighting global warming. There are two main categories of proposed technologies: carbon-dioxide removal and solar radiation management. In general, many in the scientific community and general public reject most proposed geoengineering projects for various technical reasons, as well as feasibility, cost, and their potentially devastating repercussions. Moreover, one could contend that the hubris behind the idea that humans can tinker with delicate systems that we don't fully understand is exactly what got us in this "mess." On the other hand, the other two ways to potentially combat climate change or reduce future devastation – mitigation and adaptation – aren't exactly going accordingly to plan.
While generally sounding more like science fiction than reality, weather manipulation has actually been going on for decades although not on the scale of global climate. For example, before the Beijing Olympics, the Chinese government attempted to seed clouds and produce better weather in the notoriously polluted city. Actually, city of Beijing has a special unit exclusively dedicated to weather manipulation, the aptly-titled Beijing Weather Modification Office. For the most part, they fire rockets and shells loaded with silver iodide into clouds to prevent hailstorms or produce rain. The American entrepreneur Russ George has actual geoengineering ambitions – and has been subject to a storm of controversy (and some praise) following his past attempts. In July of 2012, George led a ship that dumped iron into the Pacific Ocean in the hopes that it would produce a plankton bloom. Plankton consumes carbon dioxide and then potentially buries it underwater as it dies. George also claims the project could rejuvenate dying salmon populations. Alternatively, the plankton would just re-release the carbon back into the atmosphere.
And on Youtube videos and online chat rooms, a massive community contends that governments are already manipulating the climate using commercial jets. They identify contrails, the white condensation that sometimes follows jets, that are "thicker" and "longer lasting" as evidence. Believers of these so-called "chemtrails" say that scientists are dumping aluminum and barium into the atmosphere to reflect solar radiation, despite risks of poisoning soil and water. Others assert that chemtrails are meant for population control or even mass mind control. But most scientists contend that chemtrails are just a conspiracy theory.