Select a start year and end year from the date slider below to see a graph of annual Mean Sea Level (MSL) and it's associated annual rate of change. If a end year in the future is selected, i.e. beyond which there is available observed data, then the linear (black line) and polynomial (purple line) trendlines will show an estimate of MSL from the year which the observed data ends up to the year selected by the user.

The average annual rate of Mean Sea Level change corrected for subsidence for Tuvalu between and is approximately mm per year with a Standard Error of +/- mm. The acceleration over this period is mm/year2.

Data represented by the blue line in the above graph is the observed annual Mean Sea Level for the selected period corrected for subsidence. This is given as a height above RLR. The black line is the linear trendline for the selected period and indicates the overall direction of the data. It's gradient is the average annual rate of MSL change and is shown in the legend at the top right hand corner of the graph in the form of the straight line equation 'y = mx + c'. The purple line is the corresponding quadratic or second degree polynomial trendline.

Hover over the blue line to see individual annual MSL values in the tooltip with values corresponding to +/- one standard deviation given alongside in brackets. Hover over the legend at the top of the graph to see each trendline's equation and it's corresponding coefficient of determination, R2 value in the tooltip.

Please note that Mean Sea Level predicted from the facility to project the above trendlines into the future are estimates only.

I've created an R Shiny app which fits various degree (1-4) polynomials to the above data and also produces p-Values, R-Squared, F-Statistic and t-statistic error parameters which you can find here.

Station Documentation

Data for 1994 - 2018 retrieved September 2019 from Permanent Service for Mean Sea Level.

Cumulative subsidence correction of -1.69 mm per year from 1994 applied to above MSL data. Source: Permanent Service for Mean Sea Level.