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Movie illustrating the nominal 100,000-year cycle

This movie illustrates the general concept of glacial cycles. The movie shows only one cycle, the most recent 100,000-year cycle. The 40,000-year and 20,000-year cycles are not shown. The figures for cycle length are nominal. For example, the 20,000 year cycle is closer to 23,000 years in length and varies slightly.

The movie shows sea level falling and rising in pace with the growth and decline of glaciers, thus illustrating glacio-eustatic change in sea level. In the movie sea level rises at a constant rate, however the evidence shows that the rate was not constant. The rate of rise in sea level was greatest between 15,000 and 8,000 years before the present (BP).

This is not the whole story. Changes in relative sea level result from a combination of factors, including both eustatic sea level and vertical movement of the land. Parts of eastern and southern Sundaland are still rising relatively rapidly as mountain-building continues. By contrast, the Thai-Malay Peninsula has been relatively stable for millions of years.

Select the small movie if you have a slow internet connection.

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