Scientific Essay from the year 2023 in the subject Physics - Astronomy, , language: English, abstract: This work aims to investigate the phenomenon of unusual variations in cosmic ray intensity in the period 1981-1994, particularly in the context of interplanetary magnetic clouds and low-amplitude anisotropic wave trains. The text provides a detailed analysis of the relationship between low-amplitude anisotropic wave trains and interplanetary perturbations, particularly with respect to changes in cosmic ray intensity. By analysing data from the Deep River Neutron Monitor, the interaction between high solar wind velocities, the orientation of the interplanetary magnetic field and the proton density is highlighted.