Evidence that 1.6-year solar quasi-biennial oscillations are synchronous with maximum Sun-planet alignments (original) (raw)

2021, Cornell University - arXiv

Solar quasi-biennial oscillations, (QBOs), with period range 0.6-4 years, are prominent in records of solar activity. Here we show that the 1.6 year QBO in solar activity has the exceptional feature of phase inversion between each solar cycle in the sequence of four solar cycles, 20 to 23. The hypothesis advanced is that this feature is due to synchronicity between solar activity and planetary alignment. An index of alignment between Earth and Mercury, Venus, Jupiter and Saturn is shown to have dominant peaks of alignment separated by 1.6 years in each solar cycle with, however, peak alignments shifting by half a period, 0.8 years, between alternate solar cycles. Accepting that solar activity increases when planets align would explain the phase inversion in alternate solar cycles observed in the 1.6 year QBO. Two new methods were developed to test this hypothesis: (a) Narrow band filtering of solar activity with the pass band based on the frequency content of the planetary alignment index. (b) Superposing intervals of raw solar activity data centred on times of maximum planet alignment. Both methods provided strong support for the hypothesis. Planetary alignment is complex but predictable enabling the forecasting of solar QBO intermittency and future QBO spectral content. Highlights  1.6 year QBO in solar activity reverses phase between solar cycles  Evidence of increased solar activity when close planetary alignment occurs  Superposed raw solar activity data correlates with a planetary alignment index  Prediction of QBO intermittency based on mode change in planet alignment indices  Forecast of QBO spectral content in solar cycles 25 and 26 Keywords: Solar quasi-biennial oscillations; planetary alignments; forecasting intermittency; predicting solar activity; galactic cosmic rays; F10.7 cm radio flux 1990). These shorter term periodicities are generally known as Rieger periodicities. Later, mid-term periodicities were discovered in the period range 1 to 3 years, now referred to as quasi-biennial oscillations (QBOs), (Rouilliard and Lockwood 2004, Vecchio et al 2012). Subsequently, many studies, as reviewed by Bazilevskaya et al (2014), have been concerned with QBOs. The studies of QBOs fall into three categories: Studies that report the presence or re-emergence of specific QBO in each succeeding solar cycle, e.g. (Chowdhury and Kudela 2018, Maghrabi et al 2020); studies of the relationship between solar variables associated with a specific QBO, e.g. Rouilliard and Lockwood's (2004) study of the relationship between QBO of open solar magnetic flux and cosmic rays at 1.68 year period, and studies searching for the origin of the QBOs, e.g. Wang and Sheeley's (1995) assessment that QBOs derive from random variation of the Sun's large scale magnetic field, the Gurgenashvili et al (2016), Gachechiladze et al (2019), Zaqarashvili et al (2010), and Zaqarashvili et al (2021) assessments that QBOs are related to unstable magnetic Rossby waves in the solar tacholine, the Beaudoin et al (2016) simulation of QBOs associated with a secondary dynamo process operating in the solar convection zone, Scaffeta and Willson's (2013) evidence that the ~1.09 year periodicity in total solar irradiance is associated with Earth-Jupiter planetary alignments, and the Cionco et al (2021) assessment that periodicity in quantities like solar irradiance and F10.7 cm radio flux may be due to planetary induced variations in the Earth-Sun distance. The last category of study, the physical mechanism inducing the periodicities, is contradictory with some of the proposed mechanisms briefly reviewed by Bazilevskaya et al (2014). Interest in a planetary connection to oscillations in solar activity dates from the suggestion by Wolf (1859) that the ~decadal periodic variation in solar activity may be linked to the motion of Jupiter and Saturn. However, evidence supporting influence of planetary alignments on solar activity via a tidal influence, Scafetta (2013), or by planet torques on a non spherical tacholine, Abreu et al (2012), or by spin orbit coupling, Wilson (2013), is not mentioned in the Bazilevskaya et al (2014) review, possibly due to the planetary effect being assessed as too small, Callebaut et al (2012), or the correlations between solar activity cycles and planetary alignments assessed as statistically insignificant, Cameron and Schussler (2013), Poluianov and Usoskin (2014). However, Charbonneau (2013), suggested that sunspot-forming magnetic field concentrations, as described by Fisher et al (2000), may be subject to thresholds that could be susceptible to small planet-induced variations leading to the periodic emergence of sunspots at periods associated with planetary motions, a view supported Stefani et al (2019). Charbonneau (2013) points out that while such an effect seems unlikely, the effect, if proven, would provide a basis for forecasting (and backcasting) of solar activity. This paper is not concerned with the physical mechanism causing quasi-periodic variations in solar activity but tests the hypothesis that solar activity in the QBO period range is synchronous with planet alignments. Testing if solar activity is synchronous with planet alignment has a long and somewhat contentious history, (