Probability of exceedance of high tide levels above MLOS (metres) at Kaingaroa predicted for the 100 year period (2000 to 2099) assuming (1) no sea-level rise (heavy black line), 0.2 m rise in mean sea level by 2050 (solid blue line), and a 0.5 m rise in sea level by 2100 (light dashed line)
This suggests that the existing HAT (red line) would be exceeded by about 35% of tides assuming a 0.2 m sea-level rise spread over the 100 year period (solid blue line), and would be exceeded by all high tides assuming a 0.5 m rise in sea level (dashed line).
Text description of figure
The figure shows a line-graph of the high water height above MLOS (vertical axis) versus the log10 of the probability of exceedance of predictable high tides. The probability scale varies from 10-5 to 1. Three different scenarios are presented. In the case of no sea level rise, the graph is identical to Figure 4.2. The probability curve starts at the 10-5 end with a high water height of 0.73m above MLOS, dips only very slightly to a height of 0.69m above MLOS for a probability of 10-2, and then dips more rapidly to asymptote to a height of about 0.34m above MLOS at a probability of 1. The two other scenarios, for a 0.2m and 0.5m sea level rise respectively, essentially parallel the "no change" line except that they are 0.2m and 0.5m higher.