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A large amount of geomagnetic data of Intermagnet network observatories for 1991—2014 years have been processed and time series of induction vector components for every month were obtained. This paper presents the results of processing of eight observatories, located in different parts of the globe. For these observatories graphs of monthly values of induction vector components for four intervals of periods from the range 5—60 minutes are shown. Periodic changes in vector components (from semiannual to 11-years) are detected, as well as trends. After 2007 some increase of annual variations is seen. The most intense variations are at high geomagnetic latitudes and in the equatorial zone; they arc minimal in the middle latitudes. The nature of variations is affected both by global and regional/local factors. Investigation of these periodic changes can give an unique information on the substance and the structural features of the Earth's interior. At Polish observatories long aperiodic variation is obtained after 2008, clarifying the nature of which requires further research.

In this study we show that correspondence of the main structures of geomagnetic field, near surface air temperature and surface pressure in the mid-latitudes, reported previously in the 1st part of the paper, has its physical foundation. The similar pattern, found in latitude-longitude distribution of the lower stratospheric ozone and specific humidity, allows us to close the chain of causal links, and to offer a mechanism through which geomagnetic field could influence on the Earth’s climate. It starts with a geomagnetic modulation of galactic cosmic rays (GCR) and ozone production in the lower stratosphere through ion-molecular reactions initiated by GCR. The alteration of the near tropopause temperature (by O3 variations at these levels) changes the amount of water vapour in the driest part of the upper troposphere/lower stratosphere (UTLS), influencing in such a way on the radiation balance of the planet. This forcing on the climatic parameters is non-uniformly distributed over the globe, due to the heterogeneous geomagnetic field controlling energetic particles entering the Earth’s atmosphere.