Recurrence plot techniques for the investigation of recurring phenomena in the system earth The habilitation deals with the numerical analysis of the recurrence properties of geological and climatic processes. The recurrence of states of dynamical processes can be analysed with recurrence plots and various recurrence quantification options. In the present work the meaning of the structures and information contained in recurrence plots are examined and described. New developments have led to extensions that can be used to describe the recurring patterns in both space and time. Other important developments include recurrence plot based approaches to identify abrupt changes in the systems dynamics to detect and investigate external influences on the dynamics of a system the couplings between different systems as well as a combination of recurrence plots with the methodology of complex networks. Typical problems in geoscientific data analysis such as irregular sampling and uncertainties are tackled by specific modifications and additions. The development of a significance test allows the statistical evaluation of ...