evidence: As the industry grows, so have conspiracy theories. BBC Weather has seen a large increase in social media comments around geo-engineering since January, accusing us of covering up secret projects and wrongly blaming geo-engineering for the cool and wet weather we’ve recently had. Worldwide, there have been twice as many mentions of geo-engineering this year on X, formerly known as Twitter, than over the last six months of 2023. [...] This method of geo-engineering involves artificially adding aerosols such as sulphate into the stratosphere, which extends from 6-12 miles (10-20km) to 31 miles (50km) above the Earth. These aerosols would reflect some solar radiation, reducing the amount reaching our planet’s surface and theoretically cause a global cooling. [...] Contrails at this height actually absorb solar radiation and warm the planet and are therefore nothing to do with geo-engineering techniques currently being explored.