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How do advancing glaciers cause global sea level to fall?

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continental shelf The broad, gentle pitch of the continental shelf gives way to the relatively steep continental slope. The more gradual transition to the abyssal plain is a sediment-filled region called the continental rise. The continental shelf, slope, and rise are collectively called the continental margin.

Advancing glaciers cause global sea levels to fall because the ocean serves as the primary source of water for the formation of glacial ice. As global temperatures drop and glaciers grow, water is evaporated from the oceans and sequestered on land in the form of massive ice sheets and glaciers.123

Because this water is effectively removed from the ocean basins and stored on the continents, the total volume of liquid water in the sea decreases, leading to a drop in global mean sea level. During peak glacial stages, such as the last glacial maximum approximately 18,000 years ago, this process caused sea levels to be significantly lower—by as much as 120 to 130 meters—than they are today. This reduction in sea level exposes areas of the continental shelf that are typically submerged, effectively increasing the amount of exposed landmass.231