Milankovitch, Milutin

Much of the variation in these time series for the past 700 kyr can be described by a combination of a 100 kyr cycle plus additional cycles with periods of 20 and 40 kyr. This result immediately suggests that the ice-age cycles are caused by variations in the amount and seasonality of solar radiation reaching the Earth (insolation), because the 20, 40, and 100 kyr periods of climate history match the periods of cyclic variations in Earth s orbit and axial tilt, line hypothesis that these factors control climate was proposed by Milutin Milankovitch in the early part of the 20th century and is widely known as "Milankovitch Theory." It is now generally accepted that the Milankovitch variations are the root cause of the important 20 and 40 kyr climate cycles. The 100 kyr cycle, however, proves to be a puzzle. The magnitude of the insolation variation at this periodicity is relatively trivial, but the 100 kyr cycle dominates the climate history of the last 700 kyr. Further,... 

How is it possible to explain these dramatic changes in Earth s climate The answer to that question was provided by the Serbian mathematician Milutin Milankovitch (1879-1958). Over a period of... 

Geologists in the nineteenth century deduced that the Earth has experienced several ice ages, during which the ice sheets that cover the poles today reached much farther afield. In 1930 the Serbian mathematician Milutin Milankovitch showed how changes in the shape of the Earth s orbit around the Sun could trigger an ice age by altering the seasonal distribution of sunlight at the planet s surface. There are three cyclic variations in the orbit, with periods of 23,000, 41,000, and 100,000 years. The interplay of these Milankovitch cycles produces a complex but predictable and slow variation in climate over hundreds of thousands of years. 

The climatic cycles caused by these orbital factors are called Milankovitch cycles after the Serbian mathematician Milutin Milankovitch, who first described them in 1920. Superimposed on the Milankovitch cycles are changes in the Sun that occur over days or months or a few years. 

First, Earth s tilt changes from 22° to 24.5° and back again every 41,000 years. Second, the month when Earth is closest to the Sun also varies over cycles of 19,000 and 24,000 years. Currently, Earth is closest to the Sun in January. This month-of-closest-approach factor can make a difference of 10% in the amount of solar radiation reaching a particular location in a given season. Last, the shape of Earth s orbit varies from being nearly circular to being more elliptical with a period of 1(X),000 years. The climatic cycles caused by these orbital factors are called Milankovitch cycles after the Serbian mathematician Milutin Milankovitch, who first described them in 1920. Superimposed on the Milankovitch cycles are changes in the Sun that occur over days or months or a few years. Over the period 1979 to 1990, for example, total solar irradiance varied by about 0.1 % (Hickey et al., 1988 Willson and Hudson, 1988). 

Milutin Milankovitch was of Serbian origin, born in 1879. He obtained his PhD in Vienna in 1904 and... 

Milankovic, Milutin (1879-1958) Serbian civil engineer and geophysicist, best known for his theory of ice ages, relating variations of the earth s orbit and long-term climate change, now known as Milankovitch cycles. 

I Serbian astronomer Milutin Milankovitch developed the astronomical hypothesis in 1938 by observing that glacial and interglacial periods were related to insolation variations caused by small cycles in the Earth s axial rotation and orbit about the Sun. 

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