I want to model future coastal flooding caused by sea-level rise under the latest IPCC scenarios at global scale. To this end, I use the **Copernicus Digital Elevation Model** (Copernicus DEM: <https://spacedata.copernicus.eu/web/cscda/dataset-details?articleId=394198>). Silly me, I thought that the **elevation height of 0m** of the Copernicus DEM was the **mean sea level** of the data acquisition period of this DEM, but I have been told that it might not be the case.

Does the elevation height of 0m of the Copernicus DEM correspond to mean sea level of the **data acquisition period** of this DEM (*i.e.*, 2011-2015)? Does it correspond to mean sea level of the **vertical reference datum** of this DEM (*i.e.*, Earth Gravitational Model 2008 - EGM 2008)? Or does it correspond to an **older historical reference**?

In the Copernicus DEM metadata it is written: "Ocean water bodies are set to the elevation height of 0m, including all seas, inlets, fjords and any other extensions of the ocean."

**I need to know what this 0m elevation height corresponds to and at what elevation is the mean sea level on this DEM.**

Thank you!