Copernicus Sentinel-2 accelerates emergency response to Tonga volcano crisis - Sentinel Success Stories
Copernicus Sentinel-2 accelerates emergency response to Tonga volcano crisis
10 February 2022
Europe’s flagship Earth observation programme is supporting the rapid international response to a violent series of tsunamis that was provoked by a powerful underwater volcano eruption in the southern Pacific Ocean.
High-resolution imagery from the Sentinel-2 mission of the European Union’s Copernicus Programme helped to activate a global collaboration – that of The International Charter on Space and Major Disasters – which accelerates crisis management efforts by making satellite data freely available to the humanitarian community.
The Hunga Tonga–Hunga Haʻapai volcano – which is located about 30 kilometres southeast of Tonga's Fonuafo'ou island – first erupted on the morning of 14 January, with a second explosion taking place on 15 January at around 5:26pm local time, according to local reports. Thought to be one of the most powerful eruptions in the past 30 years, the blast fired plumes of ash, dust and steam 20 kilometres into the air, and gave rise to damaging tsunamis that hit Tonga's island groups, as well as Hawaii and Japan.
The island nation’s capital of Nukuʻalofa – located on the north coast of the island of Tongatapu – was engulfed by the tsunami and ash clouds caused by the eruption, resulting in extensive damage to vital infrastructure, including water supplies, transport routes and communications networks.
Requested by the UN Institute for Training and Research on behalf of UN’s Office for the Coordination of Humanitarian Affairs (UNITAR), the disaster charter was activated on 15 January, just over 24 hours after the first eruption.
The activation was managed by the United Nations Satellite Centre (UNOSAT) team of UNITAR, as well as a group of value-adding partners, including providers from the Copernicus Emergency Management Service (CEMS) with whom the International Charter has a cooperation scheme. It drew on data generated by numerous international Earth observation missions – including Copernicus Sentinel-2 – to deliver detailed pictures of how the disaster impacted Tonga.
The Copernicus Sentinel-2 satellites carry a single multi-spectral instrument (MSI) that samples 13 spectral bands with a swath of 290 kilometres and spatial resolutions of down to 10 metres, depending on the spectral band used. Information collected by the MSI contributed strongly to the Charter; a previous image – captured by the US Worldview-2 mission in May 2020 – was contrasted with images generated two to three days after the disaster by Copernicus Sentinel-2 and the Chinese missions Gaofen-1B/D and Jilin-1.
Using a similar method, Copernicus Sentinel-2 data were compared with WorldView-3 and Pleiades data to assess the damage to infrastructure in different areas of the Eua island, which is about 100 kilometres away from the eruption. The analysis revealed extensive damage to coastal parts of the island, with settlements and transport routes being destroyed. Less serious damage was also incurred on inland areas.
The ability of Copernicus Sentinel-2 to provide repeat observations fosters improved understanding of the impact of disasters through image analysis and change detection. Beyond the immediate crisis response, satellite imagery can also be used for recovery, rehabilitation and reconstruction.
Ferran Gascon, ESA’s Mission Manager for Copernicus Sentinel-2, says, "The Copernicus Programme in general, and the Copernicus Sentinel-2 mission in particular, have once more demonstrated their great value in helping local communities around the world through the prompt provision of open and free data for the better management of major disasters."
About the Copernicus Sentinels
The Copernicus Sentinels are a fleet of dedicated EU-owned satellites, designed to deliver the wealth of data and imagery that are central to the European Union's Copernicus environmental programme. The European Commission leads and coordinates this programme, to improve the management of the environment, safeguarding lives every day. ESA is in charge of the space component, responsible for developing the family of Copernicus Sentinel satellites on behalf of the European Union and ensuring the flow of data for the Copernicus services, while the operations of the Copernicus Sentinels have been entrusted to ESA and EUMETSAT.
Did you know that?
Earth observation data from the Copernicus Sentinel satellites are fed into the Copernicus Services. First launched in 2012, with the Land Monitoring and Emergency Management services, these services provide free and open support, in six different thematic areas. The Copernicus Emergency Management Service (Copernicus EMS) provides all operators involved in the management of Major Disasters, man-made emergency situations, and humanitarian crises with timely and accurate geo-spatial information derived from satellite remote sensing and completed by available in situ or open data sources.