- Surveyed the Tonga volcanic eruption site on its way home…“findings will help reveal the mechanism behind one the biggest eruptions of the century” -

The Ministry of Oceans and Fisheries (MOF; Minister MOON, Seong-Hyeok) announced the return of the icebreaker research vessel Araon at the Busan Port on May 3^rd (Tuesday), marking the safe completion of its 195-day voyage to the Antarctic.

During the exploration, Araon succeeded in observing the sea below the Thwaites Ice Shelf of West Antarctica, a location known to be the most vulnerable to global warming in Antarctica. The West Antarctic Ocean is a region where external warm currents flow into Antarctica below the ice shelves and thereby accelerate their disintegration and eventual collapse. The hard-to-access region, which features ice floating on the surface of the ocean, made conducting research much more difficult despite the urgent need to explore the area. Such challenges were resolved on this journey by exploring key observation points by helicopter and by attaching observation equipment on seals.

Moreover, the expedition also conducted ecological surveys of the major marine life in the world’s largest marine reserve—the Ross Sea Region Marine Protected Area. The study included penguins and seals, which are the top predators of the Antarctic marine ecosystem that feed on krill and fish. The findings from this study will be used to evaluate the health of the marine ecosystem. Furthermore, seawater was collected from the West Antarctic Ocean to analyze the carbon storage capacity of the Antarctic, which faces the looming danger of global warming. As seawater traps carbon and sinks to the bottom of the polar regions as it circulates around the globe, such circulation may be disturbed by the warming of the polar oceans. Thus, it is critical to continue monitoring the carbon cycle processes through the study of the seawater in the West Antarctic.

This Araon expedition was made even more unique in that it explored the site of the Hunga Tonga-Hunga Ha’apai submarine eruption, which reached its climax on 15^th January in the Kingdom of Tonga. With the expectation that onsite investigation conducted at the right point in time would play a pivotal role in determining the cause of the volcanic eruption, the Ministry of Oceans and Fisheries had instructed the Araon, on its way back home from the Antarctic expedition, to survey the area. K-HEART, a team of researchers led by Dr. Park Sung-Hyun of the Korea Polar Research Institute, conducted a field survey over a period of 10 days starting from April 8^th, exactly 80 days after the eruption. The Korean research team was the first to visit the site of the Tongan volcanic eruption consisting of a large investigation vessel and exploration team.

During the exploration, the team successfully secured a topographical map of the Hunga Ha’apai volcanic edifice, where the eruption had taken place. The edifice is an underwater mountain, consisting of the conduit, which vents underground magma, and other volcanic deposits. In particular, the topographical map created can be used as foundational data for uncovering the mechanism of volcanic eruptions.

The center of the Hunga Ha’apai volcanic body, which lay 150m below sea level before the explosion, was confirmed at 820m below sea level during the exploration. The eruption created a hole about 2.5x the size of the island of Yeouido in Seoul with a depth of about 700m. The new volcanic center, located 820m below the sea level, is estimated as the deepest among all submarine volcanos. Moreover, underwater drones were mobilized to the outskirts of the collapsed caldera, which showed signs of life and the resilience of the ecosystem that followed the volcanic eruption.

Araon, currently anchored at Busan Port, will once again travel to Gwangyang Port for repairs and operational maintenance, and plans to depart for its next expedition to the North Pole in July.

Director General Hong Jong Wook, the Head of the Marine Policy Bureau at the Ministry of Oceans and Fisheries, pointed out that “Araon has travelled from the hottest point (volcano) to the coldest point (Antarctic) on Earth in just over half a year” and added, “we will continue to build on the research to ensure the exploration findings brought back by Araon bears real fruit that enhances the scientific capabilities of Korea.”