If you haven't already seen Lubos' article about Milankovitch theory, then it is well worth a read, http://motls.blogspot.com/2010/07/in-de ... erard.html. It turns out that if one compares the rate of change of ice volume with the 65N insolation (rather than the ice volume itself), then the insolation changes are indeed convincingly able to explain the ice ages all by themselves - hurrah. I've noticed elsewhere, http://wattsupwiththat.com/2009/02/23/i ... sea-level/, that changes in 65N insolation are also able to explain the decrease in temperature during the Holocene. As Lubos suggests, these explanations mean that the amount of sunshine near the Arctic circle is in fact important for the global climate, which is hence determined by the residual impact of local variations, instead of the other way around. If I have understood correctly, this is a point that Mike has tried to make in several other threads on the forum.