Spectra of four different records for the period 300−9400 years BP. a) ¹⁰Be from the GRIP ice core in Greenland (Vonmoos et al. 2006). b) ¹⁴C production rate derived from the ¹⁴C INTCAL09 record (Reimer et al. 2009). c) φ record based on ¹⁰Be records from GRIP (Greenland) and Drowning Maud Land (Antarctica) and the ¹⁴C production rate (Steinhilber et al. 2012). d) Calculated torque based on planetary positions.