Confirming the lack of any sea level acceleration around the Australian coastline

[摘要] Even if sea levels fluctuate with decadal and multi decadal periodicities about a linear trend without any positive acceleration component, many papers continue to compare different compilations of tide gauges of different length and different locations or assemble selected tide gauges of selected length and location to prove that sea levels are accelerating in Australia and elsewhere in the world when they are not. It is proposed here a novel procedure fitting the tide gauge data with linear and multiple sinus functions that also iteratively completes the gaps in the recorded data with subsequent guess of the fitted function. It is shown that the tide gauges of Sydney and Fremantle, the only two exceeding a century in Australia, are acceleration free and naturally oscillating with different periodicities, phases and amplitudes for the Indian and Pacific Ocean locations. It is also shown that tide gauge records of length smaller than 60 years have rates of rise differing considerably from the legitimate long term trends, and these values may change significantly from an update to the other because of the natural oscillations. It is definitively assessed that tide gauge records of length about 20 years, with a starting point at the time of a valley of one peak and valley multi decadal oscillation for the specific of the most part of the coastline of Australia, return completely unrealistic values for the rate of rise of sea levels. The only reliable assessment of sea level trends along the coastline of Australia continues to be the determination of the rate of rise by linear fitting of all the available data in all the available station, providing the total numbers of years recorded exceed at least 25 years to make the population significant, as historically done by theNational Tide Centre of theAustralian Bureau of Meteorology prior of the censored 2009 survey. While some changes are expected in the individual values of the rate of rise fromone of these surveys to the other, and the introduction of new stations satisfying the 25 years requirement could also affect the average tide gauge result, these sea level surveys conducted without cherry picking the station and the time window generally provide about same average sea level rates of rise survey after survey.