Introduction

Question 1

What is a brief history of glaciation in Britain? (intro)

Answer 1

Covered by several “Ice Ages” over the last 500,000 years.

Most recent one ended only 10,000 years.

Glaciers and ice sheets scoured the landscape, wearing away rocks to form glacial landscapes in the Scottish Highlands, Lake Distract and N. Wales.

In the coldest periods, the ice would have been hundreds of metres thick, and reached as far south as London.

Question 2

What were the two extensive glaciations in Britain?

Anglian Glaciation

Answer 2

Anglian Glaciation 450 ka

Largest glaciation to affect us during the Quaternary with ice extending across two-thirds of Britain and Ireland down to Oxfordshire and north London, and laterally to the edge of the continental margin from western Ireland around to Norway.

Both the North Sea and Irish Sea were land and occupied by glacier ice.

Question 3

What were the two extensive glaciations in Britain?

Late Devensian

Answer 3

The second glaciation with a maximum ice sheet extent (Last Glacial Maximum) achieved at around 27ka ago.

British North Sea ice reached the Wash but there is no direct evidence for ice ever reaching into the East Midlands or beyond.

Both the North Sea and Irish Sea were land and occupied by glacier ice.

Question 4

What global climate was present during the Anglian Glaciation?

Answer 4

‘Mid-Pleistocene Transition’

Smaller, more frequent, ‘precession’ and ‘obliquity’ orbital cycles –> higher magnitude 100ka ‘eccentricity cycles’.

Far colder during ‘cold stages’ and reduce ‘seasonality’.

Pushed Polar Front further southwards and for much longer periods of time leading to parts of Britain becoming arctic tundra with the ground frequently becoming either permanently or seasonally frozen (permafrost).

Question 5

What global climate was present during the Late Devensian?

Answer 5

100ka ‘eccentricity’ orbital cycle dominates and drives big oscillations in climate between 5 warm temperate interglacial stages and 6 cold glacial stages.

During cold stages, the effect of this climate forcing is to promote the rapid build-up of ice volume within high and mid-latitude areas.