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Mean Sea Level Trends
680-140 Sydney, Fort Denison 1 & 2, Australia

The mean sea level trend is 0.65 millimeters/year with a 95% confidence
interval of +/- 0.10 mm/yr based on monthly mean sea level data from
1886 to 2010 which is equivalent to a change of 0.21 feet in 100 years.

[Metadata: Data for 1886- May 1914 are based on high and low waters and on monthly mean tide levels plus a 1.7 mm correction]

Source Data & Additional Metadata
GLOSS Station Information

The plot shows the monthly mean sea level without the regular seasonal fluctuations due to coastal ocean temperatures, salinities, winds, atmospheric pressures, and ocean currents. The long-term linear trend is also shown, including its 95% confidence interval. The plotted values are relative to the Revised Local Reference (RLR) datum as established by the Permanent Service for Mean Sea Level (PSMSL). The calculated trends for all stations are available as a table in millimeters/year and in feet/century (0.3 meters = 1 foot).

If present, solid vertical lines indicate times of any major earthquakes in the vicinity of the station and dashed vertical lines bracket any periods of questionable data or datum shifts. Source data and additional metadata are noted below the plot.

Revised: 10/15/2013
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services