Shaviv (2008) begins a most intriguing paper by noting, as background material, that "climatic variations synchronized with solar variations do exist, whether over the solar cycle or over longer time-scales," citing numerous references in support of this fact, many more of which can be found under the general heading of Solar Effects in our Subject Index.
However, it is difficult for certain people (such as climate alarmists) to accept the logical derivative of this fact, i.e., that solar variations are driving major climate changes, the prime problem being that measured or reconstructed variations in total solar irradiance seem far too small to be able to produce the observed climatic changes.