The Ice Age

The current Ice Age began around 2.6 million years ago, although the climate had been gradually cooling for almost 50 million years before then. The intensification of the cooling and the onset of the Ice Age mark the start of the present geological period, the Quaternary.

Blowing hot and cold

During the Ice Age, the climate has swung regularly back and forth between warm and cold conditions. In the colder episodes (glacials), glaciers existed in Scotland; during the warmer periods (interglacials), the climate was more like it is today and may even have been warmer.

It's still the Ice Age!

During the more intense glacials, ice sheets covered all of Scotland apart from the very highest summits. This probably occurred five or six times during the last 750,000 years, and during the many less cold episodes, smaller mountain glaciers existed in the corries and glens of the Highlands.

Today we are still in the Ice Age, albeit in a warmer, interglacial phase.

What we see today

Each successive glaciation not only helped to shape the landscape, but also removed most of the deposits of earlier glaciations. Therefore much of the evidence we see today dates from the time of the last major glacial period (the 'Late Devensian').

This last period began around 33,000 years ago and peaked about 22,000 year ago, when a large ice sheet covered all of Scotland and extended southwards to the Midlands of England.

Warming up

Around 15,000 years ago, the climate warmed rapidly, producing dramatic landscape changes as the glaciers melted, moraines were deposited, vast volumes of meltwater poured across the landscape and unstable slopes collapsed.

The climate warming was short-lived, however, and intensely cold conditions returned briefly after about 12,900 years ago when an ice cap developed in western Scotland, extending from Torridon to Loch Lomond, and small corrie glaciers formed in the high mountains.

This re-advance of the glaciers is known as the 'Loch Lomond Readvance' because evidence for it was first described from the Loch Lomond area.

Finally, around 11,500 years ago, rapid climate warming initiated the present Holocene interglacial.