When I read the lon/lat coords from the shoreline change projections into geopandas and plot those on a map the locations are incorrect. In the source data, these are correct. So it appears that something went wrong in the conversion to Zarr.
import xarray as xr
import geopandas as gpd
data = xr.open_zarr("https://storage.googleapis.com/dgds-data-public/coclico/shoreline_change_projections.zarr")
lat = data["lat"].compute()
lon = data["lat"].compute()
coords = gpd.GeoDataFrame(geometry=gpd.GeoSeries.from_xy(lon, lat, crs=4326)).sample(2000)
coords.explore()