Reconstruction of gaps in the past history of solar wind parameters

The historical (1972–2013) gaps of the solar wind parameters are filled‐in by smooth modes of covariability using the continuous geomagnetic indices with Singular Spectrum Analysis (SSA). A systematic study using experiments with synthetic gaps has been performed to determine optimal SSA parameters for reconstruction of gaps over full solar cycle and to assess the reconstruction skill. We assessed the accuracy of the SSA gap‐filling for solar wind reconstruction in T96 and TS05 empirical magnetic field models by using GOES measurements at geostationary orbit, and compared it to the results based on parameters from existing Qin and Denton interpolation. The SSA gap‐filling method does improve accuracy of empirical magnetic field models, especially when gaps are large and in particular for the TS05 magnetic field model. Key PointsSSA gap‐filling significantly improves accuracy of TS05 model in large gapsSSA provides for most improvement in correlation in large gapsSSA‐reconstructed 1972–2013 solar wind data set is included in SI