Glaciers
Glaciers are present year-round, but vary in their rate of melting. For a pack of ice to qualify as a glacier, it exist continually rather than just seasonally. For reasons that are not completely clear, the planet has experienced several major Ice Ages in its history, when glaciers extended as far south as New York, USA and Paris, France. So many glaciers piled up that the sea level was lowered by 100 m (328 ft), opening up large areas of land such as the North Sea, the Bering strait, and connecting New Guinea to the Southeast Asian mainland.
At one point in the distant past, about 700 million years ago, during the Cryogenian Period, some scientists believe glaciation may have been so severe than the entire planet was covered in an ice sheet. This has been called the Snowball Earth Hypothesis, and it is controversial, especially among scientists who doubt the geophysical feasibility of a completely frozen ocean. What is known is that the glaciers at this time were extremely large in extent, reaching the Equator in at least some areas. Interesting to note is that the first complex multicellular organisms, the Edicaran biota, appear in the fossil record almost immediately after the glaciations of the Cryogenian.
Glaciers are one of the many amazing landforms on this Earth. They affect many things in many different ways. Glaciers also form in a unique way.
Certain things must occur in order for a glacier to form. Glaciers for where there are many large snowfalls and the temperatures remain very cold all year. They form in high mountains where the snow that falls in the winter does not completely melt in the summer, while other glaciers form in the Polar Regions or the world. The snow builds up over the years and then gradually turns to ice. Repeated thawing and refreezing first transforms the snowflakes into a mass of small ice granules called firn or neve. As more snow piles on top of it, the firn becomes more and more tightly packed. Eventually, the weight
At one point in the distant past, about 700 million years ago, during the Cryogenian Period, some scientists believe glaciation may have been so severe than the entire planet was covered in an ice sheet. This has been called the Snowball Earth Hypothesis, and it is controversial, especially among scientists who doubt the geophysical feasibility of a completely frozen ocean. What is known is that the glaciers at this time were extremely large in extent, reaching the Equator in at least some areas. Interesting to note is that the first complex multicellular organisms, the Edicaran biota, appear in the fossil record almost immediately after the glaciations of the Cryogenian.
Glaciers are one of the many amazing landforms on this Earth. They affect many things in many different ways. Glaciers also form in a unique way.
Certain things must occur in order for a glacier to form. Glaciers for where there are many large snowfalls and the temperatures remain very cold all year. They form in high mountains where the snow that falls in the winter does not completely melt in the summer, while other glaciers form in the Polar Regions or the world. The snow builds up over the years and then gradually turns to ice. Repeated thawing and refreezing first transforms the snowflakes into a mass of small ice granules called firn or neve. As more snow piles on top of it, the firn becomes more and more tightly packed. Eventually, the weight