How did rising sea levels separate Great Britain from mainland Europe?

Great Britain was separated from mainland Europe primarily due to rising sea levels following the end of the last ice age, which caused the melting of glaciers and the subsequent inundation of low-lying land bridges.12

Between approximately 9,000 and 7,000 years ago, rising waters began to submerge "Doggerland," a land bridge that connected Great Britain to Denmark and the Netherlands. Simultaneously, the land bridge across the Strait of Dover, which had previously served as an exposed river valley linking England to the European continent, was finally submerged about 8,000 years ago.314

Some scientists also suggest that catastrophic tsunamis triggered by the Storegga slides—a series of massive submarine landslides that occurred between 8,400 and 7,800 years ago—may have played a role in washing away the remaining land connections between Great Britain and the continent. These geological and climatic shifts transformed the region into the island nation known today.35