Experimental data of neutron super monitors, solar wind velocity and components of the interplanetary magnetic field (IMF) have been used to study a relationship between the temporal changes of the energy spectrum of the Forbush effects of galactic cosmic rays (GCR) and the power spectral density (PSD) of the IMF's strength fluctuations. Based on the energy spectrum of the Forbush effects of GCR a structure of the IMF's fluctuations is determined in the disturbed vicinity of the interplanetary space when the direct (in situ) measurements of the IMF are absent. In order to study anisotropic diffusion propagation of GCR a second order four dimensional Fokker--Plank's type partial differential equation has been numerically solved. Diffusion, convection, drift due to the regular component of the IMF and adiabatic energy changes of the GCR particles because of the interaction with the diverged solar wind inhomogeneities are included in the transport equation. The spatial distributions of the density, radial, heliolatitudinal and heliolongitudinal gradients during the Forbush effect of GCR intensity have been found for the positive (qA > 0) period of solar magnetic cycle. It is shown that a stationary diffusion--convection--drift approximation of GCR transport is an acceptable model for describing the recurrent Forbush effects of GCR associated with the established corotating disturbances in the inner heliosphere.

PACS numbers: 96.40.Cd, 96.50.Ci, 96.50.Fm