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Data stewardship scholarship project

PALSEA was awarded a Data Stewardship Scholarship in May 2021.

Data steward

Sebastian Garzon, University of Münster 
John M. Doherty, The Chinese University of Hong Kong 


We had two main goals for this Data Stewardship Scholarship, shared between two ECRs:

1)    Filling the Holocene data into the MySQL WALIS template
2)    Expanding/improving upon the existing visualization interfaces

The work is based on the WALIS (World Atlas of Last Interglacial Shorelines) interface built in the framework of the European Research Council Starting Grant “WARMCOASTS” (PI A. Rovere). The interface was initially dedicated to Last Interglacial (and more in general, Pleistocene) sea-level proxies. Thanks to the DSS scholarship, we had the impulse to modify it to allow inserting Holocene sea-level data. As of December 2021, the web interface includes such function, built upon the template of Khan et al., 2020. We have already implemented an interface to visualize Last Interglacial sea-level data, and we are working towards including also Holocene data in the visualization.

John M. Doherty has been working towards integrating previously organized Holocene sea-level reconstructions (via HOLSEA) into the World Atlas of Last Interglacial Shorelines (WALIS) database framework. The first component of this work is to recalibrate thousands of radiocarbon-dated data points to the most recent calibration curves (IntCal20 and Marine20). We have modified an existing calibration algorithm, IOSACal, in Python. The second part of this project is to organize Holocene data into an appropriate spreadsheet format for mass recalibration. Most, if not all, of the publically accessible Holocene data, have been downloaded and organised in this way as of March 2022.

Sebastian Garzon is working on the visualization interface to the database. This part of the project consists in developing a reproducible Shiny app platform that facilitates the exploration of WALIS. During this project, the DSS has focused on two main areas:  developing tools to summarize the content of WALIS and improving the reproducibility and interaction of the platform. On the first component, a methodology was developed to merge sea-level index points with multiple temporal and relative sea-level constraints in a single constraint (Cloudpoint). This aims to facilitate the integration and comparison of sea-level indicators with other types of sea-level information (e.g., models). On the second component, the DSS has improved the backend and frontend of the initial Shiny application by including additional documentation and reducing the code complexity. This aims to facilitate code readability and guarantee the Shiny application's reproducibility.


The WALIS database the code for the visualization interface are stored in Zenodo. A page summarizing the data and code available so far for WALIS is available here:
Note that the data and visualization interface have their own DOI, as the stable versions are archived in Zenodo.

Final product

A visualization interface available through a website to query sea-level data and download the results.