the last three phases of the PDO since 1947
By studying tropical corals it was possible to recompose the index of the P.D.O. as there is a correlation between the latter and the isotopic composition of oxygen in corals collected in Fiji islands. And several trees ring resulted it also.
The evolution of the PDO on a long-term
maturity calculated from 17 tree
The P.D.O. index is defined as the monthly variability of the surface temperature of the North Pacific. Is calculated every 2 to 3 months.
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The P.D.O. experienced a cold phase from 1900 to 1924 and then a warm
phase from 1925 to 1946 followed by a cold phase from 1947 to 1976
and then another warm phase from 1977 to 1998 and a cold phase
began around since 1999. This graphic is created and updated with :
Joint Institute for the Study of the Atmosphere and Ocean (JISAO)