A significant milestone in national oceanography has been achieved through the Indonesia-China marine research collaboration. During the eighth edition of the IMPOLSE (Indonesia Maritime and Pacific Ocean Longterm Scientific Expedition) 2025, the team successfully retrieved a high-frequency deep-sea mooring (observation buoy) in eastern Indonesian waters.

The expedition, which ran from late November to late December 2025, focused on new-generation instruments that had been deployed since November 2023 at three crucial points: the northern Lombok Strait, the Labani Channel in the Makassar Strait, and the western part of the Maluku Sea.

Detection of Giant Solitary Waves

The advantage of high-frequency mooring lies in its ability to record oceanic variability with a level of precision far exceeding conventional instruments. This achievement opens up high temporal resolution for studying fast ocean dynamics, such as internal solitary waves, which were previously difficult to detect in detail.

“The amplitude of internal solitary waves, previously estimated from satellite imagery to range between 40 and 80 meters, can actually exceed 100 meters according to mooring data. This value is comparable to the maximum amplitude observed in the Lombok Strait.”

Advanced Technology and Cross-Disciplinary Integration

The IMPOLSE 2025 expedition was divided into two stages: the retrieval of moorings and advanced data collection in the eastern Maluku Sea and the Lifamatola Passage. Measurements were conducted with sophisticated instruments, including a Vertical Microstructure Profiler (VMP) and a Conductivity Temperature Depth (CTD) device.

The use of the VMP in this research is highly significant, making it the only instrument of its kind used in Southeast Asia.

Beyond physical oceanography, this collaboration integrates cross-disciplinary studies, encompassing microplastic research, biofouling, and the microbiology of microplastic degradation. It is hoped that this high-resolution observational data will form a vital scientific foundation for global climate modeling, the advancement of marine science, and the sustainable management of marine resources in Indonesia and across the wider Asian region.

Lombok Strait

The Lombok Strait is a deep waterway separating the Indonesian islands of Bali and Lombok. Historically, it has been a vital maritime passage for trade and migration, notably serving as part of the “Wallace Line”—a significant biogeographical boundary identified by Alfred Russel Wallace that separates the distinct wildlife of Asia and Australasia. Today, it remains a crucial shipping lane and a popular route for marine tourism.

Labani Channel

The Labani Channel is a natural strait located in the Banggai Archipelago of Central Sulawesi, Indonesia, historically used as a vital shipping route. It separates the islands of Peleng and Banggai, facilitating local maritime trade and transportation for centuries. Today, it remains an important passageway and is known for its rich marine biodiversity.

Makassar Strait

The Makassar Strait is a major waterway in Indonesia, separating the islands of Borneo and Sulawesi. Historically, it has been a vital maritime trade route for centuries, particularly during the era of the spice trade, connecting the Java Sea to the Celebes Sea. Today, it remains a crucial channel for international shipping and is known for its rich marine biodiversity.

Maluku Sea

The Maluku Sea is a region of the Pacific Ocean in eastern Indonesia, historically known as the “Spice Islands” for its cloves and nutmeg. This maritime area was the epicenter of the global spice trade for centuries, fiercely contested by European powers like the Portuguese and Dutch. Today, it remains a vital seaway and is renowned for its rich marine biodiversity and coral reefs.

Lifamatola Passage

The Lifamatola Passage is a deep ocean trench located in the Molucca Sea, Indonesia, historically significant as a major migration route for marine species between the Pacific and Indian Oceans. Its formation is tied to the complex tectonic activity of the region, and it has long been a critical, though challenging, navigation corridor for regional seafarers.