EOS-RS Damage Proxy Map: Tonga, Hunga Tonga-Hunga Ha'apai volcano, 22 Jan 2022, v0.5

The Earth Observatory of Singapore - Remote Sensing Lab (EOS-RS) created this preliminary Damage Proxy Map (DPM) depicting areas that are likely damaged in Tongatapu and southern Ha'apai islands of Tonga due to the eruption of Hunga Tonga-Hunga Ha'apai volcano on 15 Jan 2022. This map was derived from synthetic aperture radar (SAR) images acquired by ALOS-2 satellites operated by the Japan Aerospace Exploration Agency (JAXA) before (9 Mar 2019, 7 Mar 2020) and after (22 Jan 2022) the event.

The image covers an area indicated by the large white polygon. Each pixel measures about 30 meters across. The colour variation from yellow to red indicates increasingly more significant surface change. Preliminary validation was done by comparing with high-resolution optical imagery. This damage proxy map should be used as a guide to identify damaged areas, and may be less reliable over vegetated areas. Scattered pixels over vegetated areas may be false positives, and a lack of coloured pixels over vegetated areas may not mean no damage.

The Earth Observatory of Singapore (EOS) coordinated with Sentinel Asia to timely task the ALOS-2 satellite. Data was analyzed by the Earth Observatory of Singapore - Remote Sensing Lab (EOS-RS).

More map details and files at: http://eos-rs-products.earthobservatory.sg/EOS-RS_202201_Tonga_HungaTonga_Volcano