Why do icebergs melt and break apart as they travel south in the Labrador Current?

As icebergs travel south in the Labrador Current, they undergo a continuous process of deterioration caused by both melting and mechanical break-up.1

The primary factors contributing to their decline include:

• Melting: As icebergs drift into more temperate regions, they are exposed to warmer water temperatures. The rate of melt is dependent on the water's temperature and salinity, as well as the velocity of the iceberg relative to the surrounding water.2
• Mechanical Erosion: Wave action and turbulence around the iceberg's edges and existing irregularities, such as cracks and crevasses, accelerate erosion. This can lead to the formation of caves and the eventual collapse of unsupported sections.2
• Structural Instability: Arctic icebergs often suffer from repeated capsizes as they lose mass and stability. When an iceberg fragments into smaller pieces, it melts even faster because a larger proportion of its surface area is exposed to the water.2
• Grounding: Icebergs may run aground in shallow areas, which often leads to further structural break-up.1

Ultimately, these processes significantly reduce the mass of surviving icebergs before they reach the warmer waters of the Gulf Stream.1