Examples of (a, b) GOES-16 and (c, d) GOES-17 RO EDPs as compared with collocated ground-based ionosonde profiles. Each example also shows EDP (green line) derived from the IRI-2020 model. For ionosonde-based profiles, solid line part shows the measured bottom side part of profile, and dashed part shows the modeled topside part of Ne profile. For each panel, left plot shows a geographical map with the ionosonde location and RO tangent points projections; right plots show RO and ionosonde Ne profiles for two colocation events.