Comparison of Astronomical Theory with Data
A comparison of the solar input to high northern latitudes to the plot of ice volume [v(t)] over the past 800,000 years is not very revealing. There is no obvious relationship except that on those occasions when the ice volume drops precipitously, the solar input is on the rise. However, when one compares the solar input to the SPECMAP dv/dt, there is an apparently clear relationship. It is found that dv/dt varies inversely with the solar input. This demonstrates that the solar input is a pacemaker for the Ice Age—Interglacial cycles. However, the SPECMAP data were tuned to the solar data in the first place, so this demonstration involves circular reasoning. A comparison of the HW04 dv/dt (which does not use tuning) to the solar curve is not as convincing. But the astronomical theory (in itself) cannot predict when Ice Ages will terminate, nor why terminations are so rapid. Spectral analysis of the patterns of ice core temperature versus time or of the ocean sediment data, clearly reveal frequencies corresponding to solar variation, which again supports the conclusion that solar input to high northern latitudes is the pacemaker for Ice Age—Interglacial cycles.