__? geo glaciers

Glacial & Interglacial Periods

The earth has experienced many periods in which temperatures were much colder than they are

currently. Aside from an ice age around 300 million years ago, the most recent major ice age

occured in the Pleistocene era. The period spanned from around 2.5 million years ago

to 11,700 years ago.

During this ice age, there were many fluctuations in global temperatures:

● Glacial period: colder temperatures, causing glacial advances and sea levels to fall.

● Interglacial period: warmer temperatures, causing glacial retreats and sea levels to rise.

The most recent period of glacial advance ( Last Glacial Maximum ) was around 21,000 years

ago, and the present distribution of cold environments is much more isolated in comparison to this

period.

The world is currently in an interglacial period, meaning temperatures are higher and the majority

of our glaciers are retreating.

Historical Periods of Glacial Advance and Retreat

Glaciers have advanced

and retreated in

correlation with the

world’s glacial and

interglacial periods.

Currently, the majority of

glaciers are thought to be

retreating due to

increased temperatures. Historically, global temperatures have been increasing since Last Glacial Maximum. However,

there have been smaller global coolings in recent history that have affected the mass balance of

glaciers. The ‘Little Ice Age ’ - between 1300 and 1870 has been the most significant global

cooling in recent history.