a) Evolution of the solar open magnetic flux. The black and red lines present the estimates of the open flux from the geomagentic aa-index and from observations of the interplanetary magnetic field (Lockwood et al. 2009a,b), respectively. The blue line displays the modeled open flux from SATIRE-T. b) ⁴⁴Ti activity in stony meteorites as a function of the time of fall (see Taricco et al. 2006, and references therein). Error bars refer to 1-sigma uncertainties. The red line corresponds to the modeled ⁴⁴Ti based on the SATIRE-T open flux according to Usoskin et al. (2006b). The ⁴⁴Ti activity is given in disintegrations per minute per kilogram (dpm kg^-1) of Ni  +  Fe. The dashed red lines correspond to the estimated 1-sigma uncertanty of the model.