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A Journey to a New Land

First People
Post secondary Level Resources

Ancient Environment

The world was a much different place 20,000 years ago. Global temperatures were significantly colder than they are today, with northern oceans an average of 4 to 8 degrees colder than modern temperatures. Huge stretches of ice covered most of Northern Europe and all but the Southern tip of the British Isles. In North America, two large ice sheets the Laurentide and the Cordilleran covered Canada entirely during their largest stages, what geologists and Archaeologist call the Last Glacial Maximum (LGM).

Sea levels were also dramatically different during the LGM, due to the twin pressures of Eustacy and Isostacy. During periods of glaciations, precipitation becomes trapped in glaciers, preventing it from replenishing the Earth’s oceans. This results in a eustatic drop in sea levels. Isostatic sea level change results not from trapped water, but from the affects of ice weighing down on the Earth’s crust. This weight can affect sea levels in two ways.

Isostatic Depression is caused by the loading of the Earth’s crust in a localized area. During glacial periods, ice accumulates over a given area and its weight pushes down on the crust, causing the lowering of the land relative to sea level. When a glacier begins to melt the loss of weight results in a rising of the earth’s crust. This is known as Isostaic Rebound.

Reconstructions of both sea levels and paleoenvironments at the end of the LGM have lead archaeologists to suggest that the first people entered this new world from the west, across the unglaciated area between Siberia and Alaska, known as beringia. But how did people navigate through this difficult and unpredictable environment? When did these ancient explorers make this difficult and amazing journey?

Earliest Settlements