(Left column): the same as Figure 2, except showing at temporal higher resolution only the period of 20° of L_S centered on the winter solstice for the northern hemisphere (A), (C), (E) and the southern hemisphere (G), (I), (K). Snow generation amounts are shown for the total atmospheric column (A), (G), the upper layer (C), (I), and the lower layer (E), (K). (Right column): Fourier amplitude spectra of the time series in the left column.