A global chronologically standardised database of high-resolution proxy sea-level reconstructions since 1800 CE

Area of Science:

• Paleoceanography and Climate Science
• Sea-Level Research
• Geochronology

Background:

• Accurate relative sea-level (RSL) data is crucial for understanding modern trends and future projections.
• Existing RSL databases often use outdated radiocarbon calibration, hindering data integration and comparison.
• A unified, chronologically consistent RSL dataset is needed for the post-industrial period.

Purpose of the Study:

• To present the Post-1800 CE Sea Level Database (P-1800SLD), a global compilation of high-resolution RSL reconstructions.
• To provide a centralized, chronologically consistent dataset of sea-level index points (SLIPs) from 1800 to 2025 CE.
• To improve the accuracy and inter-comparability of RSL data by recalibrating ages and using a standardized modeling framework.

Main Methods:

• Compilation of ¹⁴C, ²¹⁰Pb, and chronostratigraphic marker data from diverse sources.
• Recalibration of 932 SLIP ages using the IntCal20 or SHCal20 radiocarbon calibration curves.
• Application of a Bayesian framework for modeling RSL reconstructions and validation against tide-gauge records.

Main Results:

• The P-1800SLD contains 932 quality-controlled SLIPs from 41 sites, with 95% derived from microfossil-based reconstructions.
• Recalibrated ages generally agree with original publications, ensuring chronological consistency.
• The database shows strong agreement with tide-gauge records (average r² = 0.82, RMSE = 0.10 m), validating its accuracy.

Conclusions:

• The P-1800SLD provides a valuable, chronologically consistent resource for studying RSL change since 1800 CE.
• This database facilitates better contextualization of modern sea-level trends and enhances future RSL projections.
• Detailed metadata support further research, database updates, and alternative modeling approaches.