Icebergs in GreenlandMichael Baynes Photography/Getty ImagesA research project experimenting with using glass beads to reflect sunlight away from the Arctic has been cancelled after test results suggested it was a threat to the food chain.The Arctic Ice Project had been testing the use of silica beads to increase the reflectivity of young sea ice, helping to preserve it through the Arctic summer.The non-profit scheme, founded in 2007 and based in California, had previously deployed the glass beads at test sites in the