This has created another problem, as most authors have looked for the cycle in the North Atlantic area, following Bond’s steps. a) Percentage of ice-rafted detrital petrology in marine sediments. Interestingly the record not only displays a clear 1500-year periodicity in phase with the DO cycle (figure 71 d), but it also has a characteristic saw-tooth aspect quite similar to the reported proxy record from the last glacial period in the Norwegian Sea (figure 29).The result has been more confusion in the scientific literature and some claims that the 1500-year cycle was perhaps of solar origin. b) Sediment grain size as a proxy for ocean current intensity. d) Sodium flux in GISP2 ice core, a proxy for atmospheric circulation. The authors conclude from the wavelet analysis that the Holocene millennial variability is composed of three main periodicities, 1000, 1500, and 2500-year cycles. And again, we find a period between 9-8,000 years BP when the record displays a 180° phase shift (figure 71 d, black bar).
However, given the strength of the solar variability signal in the North Atlantic, proxy records from that area usually present mixed periodicities more difficult to interpret. Black boxes indicate the position of the ~ 1500-year periodicity. It is therefore very interesting that the Holocene 1500-year cycle displays the same manifestation, not only in the Northwest Pacific, but also in the Southern Ocean. (2009) determined thermocline water temperature changes during the Holocene at Murray Canyon (Great Australian Bight) using the oxygen isotopic signature of another thermocline foram, .The precision of this mechanism over time suggests an astronomical control.Wolfgang Berger and Ulrich von Rad (2002) proposed that the 1500-year cycle is a harmonic of the beat between the moon’s nodal and apsidal precessions, a hypothesis that fits not only the observed period, but also the required mechanism for vertical water mixing through tidal forcing.As described, DO events cannot take place during the Holocene.It is too warm, there is too little ice, and sea level is too high.