Solar activity and climate change are characterized by specific oscillations. The most relevant ones are known in the literature as the cycles of Bray±Hallstatt (2100±2500 year), Eddy (800±1200 year), Suess±de Vries (200±250 year), Jose (155±185 year), Gleissberg (80±100 year), the 55±65 year cluster, the 40±50 year cluster plus bidecadal and decadal oscillations, and others.
Herein I review some of my publications on this topic and show that these oscillations emerge from a specific set of planetary harmonics – the orbital invariant inequalities – produced by the Jovian planets (Jupiter, Saturn, Uranus, and Neptune) and other basic astronomical frequencies related to the soli-lunar tides and orbital period of the planets. The result suggests that both solar activity and climatic changes are modulated by harmonic planetary forcings. Since these same harmonics are also found in the climate system, they can be used, in first approximation, to model and forecast climate change.
As an example, I briefly comment and update a semi-empirical model for climate change proposed 8 years ago by the author (Scafetta, Earth-Science Reviews 126, 321, 2013), which uses some of the above astronomically determined oscillations in addition to volcanic and anthropogenic compoments. The proposed model’s result continues to surpass the performance of the CMIP5 models used by the IPCC, in particular after 2000, in reconstructing the global surface temperature record.
Continue reading: Planetary, Solar and Climatic Oscillations: An Overview. By Nicola Scafetta.