Global Oceans

Annual average global mean sea level (GMSL) from satellite altimetry (1993–present; Beckley et al. 2021) reached a new high in 2023, rising to 101.4 mm above 1993 (Fig. 3.15a). This marks the 12th consecutive year (and 28th out of the last 30) that GMSL increased relative to the previous year, continuing a multi-decadal trend of 3.2±0.4 mm yr−1 and acceleration of 0.075±0.025 mm yr−2 in GMSL during the satellite altimetry era (Fig. 3.15a). A quadratic fit with corrections for the eruption of Mount Pinatubo (Fasullo et al. 2016) yields a climate-driven trend of 3.1±0.4 mm yr−1 and acceleration of 0.092±0.025 mm yr−2 (updated from Nerem et al. 2018).