Context

The world's (former) largest iceberg continues to break apart into smaller pieces on the doorstep of a major marine wildlife haven and home to millions of macaroni and king penguins in Antarctica. It has now split into 4 distinct pieces.

About

What is iceberg A68?

• A68a became the world's largest iceberg when it split from Antarctica's Larsen C ice shelf in July 2017. A68a is an iceberg roughly the size of the state of Delaware.
• The massive chunk of ice has been drifting northward ever since. As recently as April, it measured 2,000 square miles (5,100 square kilometers), or just over the size of the state of Delaware. 
• Since then it has been drifting towards the remote island of South Georgia, which is a British Overseas Territory (BOT).
• On its journey, smaller icebergs have calved from the iceberg and right now, the biggest section of the iceberg is called A68a and spans an area of roughly 2,600 sq. km. 

Areas of the new fragments A-68a: 1,004 square miles (2,600 square km) A-68d: 56 square miles (144 square km) A-68e: 253 square miles (655 square km) A-68f: 87 square miles (225 square km)

What are icebergs?

• Icebergs are pieces of ice that formed on land and float in an ocean or lake. Icebergs come in all shapes and sizes, from ice-cube-sized chunks to ice islands the size of a small country.
  • The term "iceberg" refers to chunks of ice larger than 5 meters (16 feet) across.
  • Smaller icebergs, known as bergy bitsand growlers, can be especially dangerous for ships because they are harder to spot.
• The North Atlantic and the cold waters surrounding Antarctica are home to most of the icebergs on Earth.

Iceberg calving

• Icebergs form when chunks of ice calve, or break off, from glaciers, ice shelves, or a larger iceberg.
• Icebergs travel with ocean currents, sometimes smashing up against the shore or getting caught in shallow waters.
• The iceberg’s calving is thought to be a natural event and not a result of climate change.
• However, some models predict that a warming Antarctica in the future could mean more calving events as ice shelves and glaciers retreat.

What’s next?

• It is now hoped that the biggest pieces will be carried north of the island on a fast-moving current known as the Southern Antarctic Circumpolar Current Front.
• However, if any of the pieces, or any potential new pieces, were to get caught on the shelves, they could still be big enough to cause disruption to the local wildlife.