A newly reconciled dataset for identifying sea level rise and variability in Dublin Bay

Abstract

We provide an updated sea level dataset for Dublin for the period 1938-2016 at yearly resolution. Using a newly collated sea level record for Dublin Port, as well as two nearby tide gauges at Arklow and Howth Harbour, we perform data quality checks and calibration of the Dublin Port record by adjusting the biased high water level measurements that affect the overall calculation of mean sea level (MSL). To correct these MSL values, we use a novel Bayesian linear regression that includes the mean low water values as a predictor in the model. We validate the re-created MSL dataset and show its consistency with other nearby tide gauge datasets. Using our new corrected dataset, we estimate a rate of sea level rise of 1.1gmmgyr-1 during 1953-2016 (95g% credible interval from 0.6 to 1.6gmmgyr-1), and a rate of 7gmmgyr-1 during 1997-2016 (95g% credible interval from 5 to 8.8gmmgyr-1). The overall sea level rise is in line with expected trends, but large multidecadal variability has led to higher rates of rise in recent years.