Past sea level

Sea level variations over geological time scales

Global or barystatic sea level has fluctuated significantly over Earth's history. Over geologic time scales, the primary factors affecting sea level are the volume of available water due to growth or melting of ice caps, and the storage volume of the ocean basins due to plate tectonics. The secondary and tertiary influences on water volume are sedimentation, oceanic plume volcanism, the temperature of the seawater, which affects density, and the amounts of water retained in other reservoirs like aquifers, glaciers, lakes, and rivers.

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