Provides tools for analysing annual average ocean water level time series,
estimating mean sea level trends, velocities, and accelerations using Singular
Spectrum Analysis (SSA). The detailed methodology for resolving mean sea level
with improved temporal resolution follows Watson (2018)
"Improved Techniques to Estimate Mean Sea Level, Velocity and Acceleration from
Long Ocean Water Level Time Series to Augment Sea Level (and Climate Change)
Research" < https://unsworks.unsw.edu.au/entities/publication/5e835c87-aa0a-4457-807e-29d354e91d45>.
Additional methodological developments and applications are described in Watson (2020)
"Status of Mean Sea Level Rise around the USA"