ABSTRACT
For the investigation of a Sun-weather relationship, climate as well as solar change history has to be known in detail. A notable feature of solar change is the spottiness of the Sun which can be expressed at any time as the number and area of visible sunspots. Another expression of solar change is found in a variable distribution of charged particles in the interplanetary regions occupied by the solar wind plasma. The magnetic fields associated with these particles deflect a portion of the galactic cosmic ray flux directed towards the Earth. Because changes in the magnetic properties of the plasma originate at the Sun's surface, the intensity of cosmic rays measured on our planet depends on the surface conditions of the Sun. The relationship is such that cosmic ray intensity near our planet decreases when sunspot numbers increase. By monitoring the variable production rate of cosmogenic isotopes such as 14C in our atmosphere, a time history of solar change can be obtained.
