- The Earth’s oceans used to be green — and could one day turn purple, scientists say Live Science
- Earth was once a “Green Marble” before its oceans turned blue Earth.com
- Earth’s Oceans Were Once Green, Says Study of Volcanic Waters ScienceAlert
- ‘Green, red, even purple’: The true colors of Earth’s past and future oceans Business Today
- Earth’s ocean might turn PURPLE one day – and scientists say it used to be a totally different colour too The Sun