Welcome to Sea Level New Zealand. A resource for New Zealand sea level rise information.
Below are the five New Zealand locations with the longest sea level records. Click on a location to see an interactive chart showing current and historical Mean Sea Level (MSL) for that location. You can choose a start and end year and then see a updated chart of annual Mean Sea Level along with the associated annual rate of Mean Sea Level rise for the selected period.
Below are some selected locations from outside of New Zealand to enable comparisons with the rest of the world. I'll be adding more as I get the time.
The below chart summarises the above five NZ locations in one chart. In the table below the chart, the mean annual rate of Relative Sea Level (RSL) rise for the selected period for each location is also provided, along with the corresponding Vertical Land Movement (VLM) and the resultant rate of Absolute Sea Level (ASL) change which is RSL corrected for VLM. The last row of the table gives the mean of RSL, VLM and ASL of the five locations for the selected period. Please use the date slider above the chart to select different start years and end years. The chart and the data in the table below the chart with then update automatically.
Click on the location name above or in the below table to see an individual chart for that location showing additional information such as annual Standard Deviations (for NZ locations) in annual Mean Sea Level, a facility to estimate future Mean Sea Level, corrections for Vertical Land Movement (VLM), acceleration and source data information.
| Location | RSL (mm/year) - | VLM (mm/year) | ASL (RSL+VLM) (mm/year) |
|---|---|---|---|
| Auckland | +/- | +/- | +/- |
| Taranaki | +/- | +/- | +/- |
| Wellington | +/- | +/- | +/- |
| Lyttelton | +/- | +/- | +/- |
| Dunedin | +/- | +/- | +/- |
| NZ Mean | +/- | +/- | +/- |
Please note when using the charts on this site that at least 50-60 years of Mean Sea Level data is required to establish a robust long term trend.
Check out the Extreme Tides page by clicking on the "Tides" link above which summarises the extreme tides recorded around NZ.
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 in the navigation menu at the top of this page.
Please use the above Contact page for any feedback.