GEOLOGY

Detailed explanation-1: -Between 130, 000 and 114, 000 years ago, the ice retreated during the Eemian interglacial – and then advanced again to create the glacial that most people know as “the ice age”.

Detailed explanation-2: -During an interglacial, sea levels rise as ice sheets and glaciers melt with the increase in temperature, thus resulting in an increase in volume of the ocean as water is heated.

Detailed explanation-3: -Within an ice age are multiple shorter-term periods of warmer temperatures when glaciers retreat (called interglacials or interglacial cycles) and colder temperatures when glaciers advance (called glacials or glacial cycles).

Detailed explanation-4: -The fluctuations between glacial and interglacial states are driven by changes in Earth’s orbit around the sun-called Milankovitch Cycles-that change the amount of incoming solar radiation called insolation (Figure 2a) (Hays et al.

Detailed explanation-5: -During this last glacial period, alternating episodes of glacier advance, and retreat occurred. Within the last glacial period, the Last Glacial Maximum was approximately 22, 000 years ago.