One of the most geologically dramatic events in the history of the Channel Islands was the sea-level rise that followed the end of the last Ice Age.

As global temperatures increased after approximately 18,000 years ago, the great ice sheets of the Northern Hemisphere began to melt.

The enormous quantities of water they had sequestered — water that had been removed from the ocean through evaporation and precipitated as snow and ice over thousands of years — returned to the oceans.

Sea level rose, globally, over the subsequent millennia.

The rise was not uniform in rate: there were periods of rapid rise, periods of slower rise, and complex local effects from the removal of ice mass that had been depressing the land beneath it.