Delving into deep sea: China joins global scientists in exploring hadal zone

A pioneering international initiative for hadal zone exploration, led by Chinese scientists, has received official approval from the United Nations Decade of Ocean Science for Sustainable Development (2021-2030).

The Global Hadal Exploration Programme (GHEP), spearheaded by Institute of Deep-sea Science and Engineering (IDSSE) under the Chinese Academy of Sciences (CAS), aims to transform fragmented hadal research into a coordinated global mission to explore, understand and protect the planet's most inaccessible marine ecosystems.

The hadal zone comprises primarily of ocean trenches, particularly from a depth of 6,000 meters to the bottom of the ocean up to about 11,000 meters. The hadal environment is characterized by extreme depths and pressures, darkness, low temperatures, frequent earthquakes, and peculiar living forms.

For a long time, the hadal trenches have been among the most under-explored and mysterious areas on Earth due to technological limitations.

China has been a key driver of deep-sea exploration over the past decade through sustained sci-tech advancements. In 2014, the CAS launched the Hadal Science and Technology Program, followed by a historic dive to the Mariana Trench's 10,000-meter depths in 2016. By 2022, the CAS initiated the Global Trench Dive and Exploration Programme, leveraging its cutting-edge manned submersible Fendouzhe (Striver) and the Tansuo research vessels.

"Venturing deeper is about understanding our ocean so we can coexist with it," said Du Mengran, a lead researcher at IDSSE.

"Global cooperation in these 'untouched zones' will redefine the boundaries of marine science and provide critical knowledge for deep-sea conservation and sustainable use," she said.

To date, Chinese scientists have collaborated with 145 researchers from 10 countries, exploring nine hadal trenches worldwide, including the Mariana, the Kermadec and Puysegur trenches.

Starting from this year, GHEP will unify international research on extreme environments, life evolution, and geological processes in the hadal zone. The program will establish international research hubs, organize joint deep-diving expeditions, and host regular symposia while offering training and open access to samples, data, and facilities -- particularly for young scientists, Du added.

GHEP brings together research institutions from New Zealand, Denmark, Germany, Chile, France, Indonesia, Brazil, Russia, India, Cook Islands, Papua New Guinea, Singapore, Portugal and other countries.