Milankovitch Cycles

http://www.eoearth.org/article/Milankovitch_cycles

Scotsman James Croll combined the eccentricity of the orbit and the precession and in the 1860s and 1870s presented his ideas on the effects of the cycles and how they might influence climate, especially the colder winters when they correspond with the aphelion. In fact, what are typically called ‘Milankovitch Cycles’ are sometimes referred to as ‘Croll-Milankovitch Cycles.’