Virunga Volcanoes Supersite Biennial Report: 2020- 2021

The Virunga was established in November 2017 as a permanent Supersite with the aim of improving the geophysical scientific research and Geohazards assessment in support of Disaster Risk Reduction (DDR) in the Virunga Volcanic Province and the Lake Kivu basin. The CEOS guarantees a free access to Earth Observatory (EO) data, while the pool of collaboration built around the Supersite potentially supports the access to equipment for ground-based data collection and processing. From November 2017 to November 2019, in addition to implementing the Supersite; collaboration was built between the GVO and the world leading observatories and agencies, the free access to EO data with first steps towards collecting some ground-based data, training of some local scientists, and the adhesion to the Virunga Supersite of world top-level geoscientists in the field of active volcano monitoring and hazards assessment. The later allowed the assessment of volcanic hazards around Nyiragongo and Nyamulagira, which included the production of hazards maps for future volcanic eruptions management, the collection of ground-based data to produce Risk and Recovery mapping. On the evening of May 22nd 2021, Nyiragongo volcano suddenly erupted from three vents that opened along a system of fractures on the southern flanks of the volcano. Two major lava flows were produced with one having its direction toward Goma city. Fortunately, these lava flows stopped their run before reaching the densely populated areas, with one being only at ~1 km from the Goma international Airport. Still, the lava flows had already destroyed about 3,600 houses while another 1,000 were severely damaged causing at least 30,000 persons to be in the need of shelter and other humanitarian assistance. The volcanic eruption further caused the death of 38 persons, disrupted the water supply infrastructures in Goma and the surrounding: estimated 550,000 persons lost access to water. An intense seismic activity followed the eruption and persisted for ~2 weeks, and caused sever damages to houses and infrastructures such as roads, water and electricity networks. Furthermore, the earthquakes caused important ground deformation in Goma and Gisenyi cities, which brought the fear of magma rising and accumulating beneath Goma and Lake Kivu. This raised a scenario of a new eruption with active vents inside Goma city or Lake Kivu, and led local authorities to evacuate estimated 400,000 people. Virunga Supersite scientific team supported the response to the Nyiragongo 2021 volcanic crisis through data processing, which yielded the production of key information that was delivered to local authorities and supported the management of the volcanic and humanitarian crises. In September 2021 a new effusive activity began inside Nyiragongo main crater, along with a sustained seismic activity and ground deformation to the southern flank of the volcano. The fast renew of the activity denotes the strong and urgent need to starting prepare for the next Nyiragongo volcanic eruption; and the Virunga Supersite is willing to be part of this goal. This preparation strongly need an enhanced monitoring infrastructure that would permit follow up the complex Nyiragongo-Nyamulagira rift-zone volcanism, forecast the spatiotemporal extent of the next eruption which will reduce its impacts. Furthermore, a proper training of local scientists is part of the well properness to the next Nyiragongo crisis, which the Supersite has already started