Simulated and ERA5 fields showing the PL on 25 March 2019 at 0000 UTC.

The colourmap represents the 1000-500 hPa thickness (dam), the black isobars represent the SLP (hPa, contours every 2 hPa) and the red dashed lines represent the geopotential height at 500 hPa (dam, contours every 2 dam). The black outlining represents the coastline, and the white dashed line represents the sea ice edge, which is defined as the 0.15 contour of the sea ice concentration. ERA5 fields have been interpolated to the grid of the simulation using bicubic interpolation for the SLP, 1000-500 hPa thickness, and geopotential height, and bilinear interpolation for the sea ice concentration. The sea ice edge in ERA5 corresponds to the 25 March 2019 at 1200 UTC. The dataset used to plot the geographic contours has been obtained from the GSHHG [33] under a CC BY license, with permission from Dr. Paul Wessel.