Antarctica’s oldest iceberg is turning blue and about to disintegrate

The world’s largest iceberg, A23a, in the Scotia Sea between Antarctica and South Georgia (Juergen Brand/shutterstock.com)

Iceberg A-23A has been around since 1986, when it broke off from Antarctica at nearly twice the size of Rhode Island. It spent more than 30 years grounded in the shallow waters of the Weddell Sea before breaking free in 2020, then go…