709 / 2024-09-19 09:48:59

Closing the budget of sea level rise trend and its acceleration from 1960 to 2023

sea level,acceleration,misclousre,climate change

Session 23 - Sea level rise: understanding, observing, and modelling

Ensuring the closure of the global mean sea level (GMSL) budget is essential to understand the causes of GMSL rise. Not only that, GMSL is also accelerating, but its closing of the acceleration budgets has remained challenging since 1960. This study accounts for the recent progress in GMSL, steric sea level and ocean mass estimates to assess the budget for the GMSL trend and its acceleration for the three key observational eras of 1960-2020, 1993-2020 and 2005-2020, respectively. For 1960-2020, the trend of GMSL is 1.83±0.40 mm yr^-1, closely matching contributions of 1.85±0.13 mm yr^-1, with the key contribution from steric sea level, followed by glacier. Additionally, the observed GMSL acceleration of 0.072±0.005 mm yr^-2 for 1960-2020 matches contributions of 0.071±0.000 mm yr^-2, dominated by steric sea level. From 1993 to 2020, the GMSL rise of 3.25±0.10 mm yr⁻¹, also aligns with contributions of 3.24±0.14 mm yr⁻¹. For 2005-2020, the observed GMSL acceleration is 0.108±0.026 mm yr^-2, mainly driven by steric sea level at 0.116±0.017 mm yr^-2. This study demonstrates that recent observations are capable of reconciling the observed GMSL with the sum of contributors, highlighting the importance of adequate data processing and bias corrections.