Glaciers.

。A glacier is a huge river that has existed for many years and consists of ice. In year-round frozen mountains or polar regions, years of snow are squeezed into ice by gravity, which then slides down slopes to form glaciers. Glaciers in the polar regions, also known as continental glaciers, cover a wide range and are a legacy of the Ice Age. Glaciers are the largest freshwater resource on earth and the largest natural reservoir after the ocean. With the exception of Australia, glaciers are available on seven continents.

because glaciers form in permafrost areas, the study of glaciers can help us find geological information from ancient times. Because the greenhouse effect is particularly pronounced at high latitudes and at high altitudes, glaciers on Earth are disappearing at an alarming rate. For glaciers that flow directly into the sea, this represents an increase in the number of giant icebergs, rising sea levels and possible flooding in coastal areas;

as the glacier advances, it cuts the rocks on both sides of the valley and takes them downstream far. As the glacier retreated, the huge stones were left on the banks of the original glacier, including on both sides of the hillside. The valley through which the glacier flows will be sculpted from the original v-shaped cross-section into a u-shaped cross-section.

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