Sea level trajectories and recent records at Australian tide gauges

Australian mean sea levels are rising faster than in the past. We find that sea level is accelerating by 0.113 ± 0.065 mm year−2, based on national tide gauge-based composite mean sea level anomalies from 1966 to 2022. Half of all Australian tide gauges recorded their highest-on-record annual mean sea levels in either 2021 or 2022 and 77% of all current monthly mean sea level records were set since 2010. Record flood levels were set 2.4 times more frequently since 2010 than would be expected without sea level rise and variability. Assuming recent accelerations persist, established methods can be used to estimate that Australian mean sea level will be 0.26 ± 0.03 m above 1995–2014 levels for 2050. This trajectory suggests that higher sea-level rise scenarios represent pathways more consistent with the observed sea-level rise trajectory over the past 50 years.