Two pendulums swinging side by side gradually begin to influence each other. The same happens with two plasma flows inside the Sun. One flows closer to the surface, the other deeper, and each has its own rhythm: 12.05 and 9.52 years. When the two oscillations combine, a slow beat emerges: the strength of the combined rhythm rises and falls every 89 years. This explains the Gleissberg cycle, the long wave in solar activity.
The same approach explains the ocean as well. El Niño has two oscillations: 5.35 and 3.55 years. Their sum produces a slow beat with a period of 21.5 years. That is exactly the signal found in the rings of the Yakushima cedar, which has been growing on Yakushima Island since 1924. So the 22-year rhythm in the wood was left not by the Sun but by the warm current of the Pacific Ocean. This used to be a puzzle, but now it all fits: two pendulums in the sky and two in the sea leave a common mark on the Earth.
The Yakushima cedar, whose rings revealed the 22-year signal, lives on Yakushima Island, where annual precipitation reaches 4000–10000 mm, making it one of the wettest places in Japan.