The world’s largest iceberg, a one trillion tonne so-called “megaberg", is posing a huge disaster risk, as it drifts into warmer and shallower waters of the South Atlantic Ocean. It is feared it could break into large sized chunks and block access to food for the region’s animals. Sky science and technology editor Tom Clarke flew over the iceberg, known as "A-23-a", to get a birds-eye view of the scale. Read more: https://news.sky.com/story/what-we-learn-flying-over-the-worlds-largest-iceberg-