A pumice raft drifts amid the South Pacific near Tongas

Sentinel-1 CSAR IW acquired on 11 August 2019 at 17:08:00 UTC
Sentinel-2 MSI acquired on 11 August 2019 at 21:59:19 UTC
Sentinel-2 MSI acquired on 16 August 2019 at 21:59:21 UTC
Sentinel-2 MSI acquired on 21 August 2019 at 21:59:19 UTC
Author(s): Sentinel Vision team, VisioTerra, France - svp@visioterra.fr
Keyword(s): Water colour, volcanoes, geohazard, marine traffic, ship security, Tonga islands, Pacific Ocean
Fig. 1 - S2 (11.08.2019) - 11,8,2 colour composite - A pumice raft formed near Tonga Islands after a submarine eruption on 07.08.19.
The same volcano is already responsible for several occurrences of this rare event in the past.
Fig. 2 - S1 (11.08.2019) - vv,vh,ndi(vh,vv) colour composite - A radar acquisition the same day confirms its heterogeneity in density.
Fig. 3 - S2 (16.08.2019) - 11,8,2 colour composite - Measuring over 150 km², it looses its density as it drifts and widens.
Fig. 4 - S2 (21.08.2019) - 11,8,2 colour composite - Denser areas show in brown on this composite.