3. Glaciers through time

The ‘glacial theory’ championed by Louis Agassiz in the 19th century saw the beginning of the geological community’s partial acceptance of the concept of multiple and more extensive glaciations. Formal recognition of multiple glaciations came in 1909 with Penck and Brückner’s Alpine model. Since then, research on the Earth’s climate record has established a firm understanding of the nature and pace of climate change over the last 2.6 million years and the impact these changes have had on glacier development and extent. ‘Glaciers through time’ considers the periods of ice ages, glacials, and interglacials, describing changes in ice sheets, mountain icefields, and the impact of melting glacier ice on sea level rise.