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Explore the Milankovitch Theory of orbital forcing on ice sheets through variations in tilt, eccentricity, and precession, impacting summer and winter insolation that drive ice growth and retreat over millennia.
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Milankovitch Theory of orbital forcing of ice sheets Tilt variations eccentricity variations precession of perihelion
Low High Latitude NH summer insolation Allows ice sheets to grow from year to year
Milankovitch Theory: Variations in high latitude (65 N) summer insolation combine with climate system feednack processes drives ice sheet growth and retreat on time scales of 10,000 yrs to 100,000 yrs.
High insolation Low insolation
Solar insolation Surface temp albedo Ice volume Bedrock sinking Southern edge Ice height Base ablation
When high latitude NH summer insolation is below the threshold ice sheets grow slowly. When high latitude NH summer insolation is above the threshold ice sheets quickly retreat. a sawtooth pattern. Gradual buildup and rapid deglaciation.