Abstrait

Discussion of timescales for detecting a significant acceleration in sea level rise by parabolic fittings of naturally oscillating time series

Albert Parker

The authors of[20] are only the last of a long series[21-26] to apply parabolic fitting with different time windows to the time series of relative sea levels from tide gauges to assess the presence of positive or negative accelerations. This method is wrong because this approach produces positive or negative accelerations even dealing with simple sinusoidal oscillations about a linear trend where the acceleration is clearly zero, as it is the case of purely oscillating tide gauges signals. This contribution proposes clear and strong concerns about the validity of any claim made on the basis of parabolic fittings and propose a better analysis methods clearing the trends of the multi-decadal variability.