Summary: | The impact of elastic vertical land movement (VLM) on relative sea levels along the world's coastlines is significant. In Northern Europe, VLM is mainly due to the effect of Glacial Isostatic Adjustment (GIA). However, the rapid melting of ice in the Arctic is causing a substantial elastic uplift with both a local, but also a long-range footprint of 1000-3000 km from the point of ice loss. When VLM estimates from GNSS are unavailable, sea-level studies based on tide gauges often rely on a GIA-only VLM model to correct any ongoing uplift, but in Arctic regions, this can lead to underestimation of the uplift or overestimation of the absolute sea-level change due to significant changes in present-day ice loading (PDIL). Here, a high-resolution time-varying elastic VLM model (5x5 km) is developed from high-resolution estimates of glacial and Greenland Ice Sheet mass balance is presented. The elastic VLM model is combined with a GIA model to create a complete VLM model that is comparable with GNSS-measured VLM rates (in a center of mass frame). Additionally, far-field elastic effects from the Antarctic and Terrestrial Water Storage are included to create a complete vertical deformation map for the Northern Hemisphere, that can complement sea level studies in areas with few or no GNSS measurements.
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