The phrase "year oscillation" refers to a repeating pattern or cycle that occurs over the course of one year. It means that something goes through regular ups and downs or back and forth movements within a year's time. Full definition
The phase of the 60 - year oscillation found in the tide gauge records is such that sea level in the North Atlantic, western North Pacific, Indian Ocean, and western South Pacific has been increasing since 1985 — 1990. (judithcurry.com)
Increasing since 1985 — 1990 with a 60 - year oscillation means we all get together sometime during 2045 - 2050 to watch it start rising again from a level lower than it is today? (judithcurry.com)
The assumption that a complete quasi-60 year oscillation just happens to be within the temperature range being studied is silly. (wattsupwiththat.com)