Reykjanes ground deformation from satellite radar

Sentinel-1 InSAR (ascending track 16). GPS from the Icelandic Met Office is used to separate vertical from horizontal motion.

 
No unwrapped radar pairs in this period:
values are interpolated
−+ cm

Time series

Click or tap the map to choose a point (or a GPS station). Red lines mark eruptions (approximate dates); shaded areas are data gaps.

About this

Data: Copernicus Sentinel-1, processed by COMET LiCSAR (unwrapped interferograms, frame 016A_02504_162118). Pairs of up to 120 days were inverted per pixel into a displacement time series (own processing, approx. 0.5 km pixels). GPS: Icelandic Met Office via Quake.run.

One look direction: the satellite measures only the change in distance along its line of sight. Uplift moves ground toward it (+), but so does motion to the west; sinking and motion to the east both move ground away (−). Around the Svartsengi inflation and the dike intrusions the GPS stations moved horizontally by 40–95 cm between April 2024 and July 2026 (west of the fissure to the west, east of it to the east), so the raw view shows a blue area east of Svartsengi that is mostly eastward motion, not subsidence.

Vertical view: the horizontal part is removed using a model fitted to the GPS stations (a deflating/inflating point source at about 5.5 km depth plus dike opening along a NE-striking fissure). Held-out GPS stations are predicted to about 3 cm. Compared with GPS vertical at 26 stations (4 Apr 2024 to 30 Jul 2026): correlation 0.99, RMS difference about 4 cm, InSAR about 10% high. The correction is least certain within a few km of the dike line, where the narrow blue strip may be partly an artefact. Coloured dots show the GPS vertical for comparison.

Limits: the vertical view starts on 4 Apr 2024. Before that, LiCSAR has no unwrapped pairs covering the first dike and eruption phase (Nov 2023 – Mar 2024), and the site's GPS data begins in Nov 2023, so only the raw line-of-sight view covers 2020–2023 (it has an interpolated gap Mar–Nov 2023). No atmospheric correction (a few cm of noise); no coherent data on fresh lava or in snow; the western tip of the peninsula is outside this frame. Eruption dates are approximate.

Keyboard: space = play/pause, ← → = step.