What lies beneath

Unlocking mysteries of the deep sea can help protect the planet and mankind

It is no secret that scientists and explorers believe the deep oceans are Earth's final frontier. While nearly all the land on Earth has been mapped by modern gadgets, more than 80 percent of the oceans remained unexplored as of last year, according to the National Ocean Service in the United States.

The oceans are more than the lifeblood of the Earth, driving weather, regulating temperature and ultimately supporting all living organisms. Throughout human history, they have also been a key source of sustenance, transportation, commerce, growth and inspiration.

During the National Science and Innovation Conference in 2016, President Xi Jinping said the deep sea is full of untapped treasures and potential, but accessing those treasures will require China to obtain key technologies in deep-sea access, deep-sea surveys and deep-sea development.

In 2015, the World Wide Fund for Nature estimated the economic value of the oceans to be more than $24 trillion, based on existing data at the time. Unlocking the mysteries of the deep seas can reveal new sources for medical drugs, food and energy resources.

It is also crucial for obtaining knowledge to predict natural disasters such as earthquakes and tsunamis, as well as understanding how to protect the marine environment and biosphere.

With these lofty goals in mind, eager inventors and explorers from a small pool of countries have been racing to dive into the unknown. In recent years, China has entered the race with a splash, hoping to become a maritime power as highlighted by Xi during the 19th National Congress of the Communist Party of China in 2017.

In June 2012, China's first deep-sea manned submersible, Jiaolong, named after a mythical sea dragon, set a world diving record for submersibles of its kind by plunging to 7,062 meters in the Mariana Trench in the Pacific Ocean.

The feat made China the fifth country, after the United States, Russia, France and Japan, to have the ability to send humans deep into the sea. This also meant the country is now capable of exploring more than 99.8 percent of the ocean floor, according to Liu Cigui, director of the State Oceanic Administration.

The administration said that next year Jiaolong will commence its first round-the-world voyage, which will last about a year, to survey and research the deep-sea environment and resources in the Pacific, Atlantic and Indian oceans. China is also building a new manned submersible that can reach a depth of 11,000 meters, and is using all domestically made components.

During a 2017 expedition in the Indian and Pacific oceans, Jiaolong undertook 30 dives, collecting more than 600 kilograms of seabed examples, along with 2,115 marine creatures.

Chinese scientists also discovered 27 thermal vents deep in the Indian Ocean that support a wide variety of life-forms, from tiny microbes that thrive under high pressure and temperatures to ghostly white fish, crabs and shrimps.

In April, Sylvia Earle, a marine biologist and oceanographer from the US, told Xinhua News Agency that China now leads the world in certain areas of deep-sea exploration. She hailed Jiaolong and the Rainbow Fish series of unmanned deep-sea landing devices, commenting that "this is the greatest era of exploration ever".

Last year, a second-generation Rainbow Fish reached a depth of more than 10,900 meters. The device was built by the Shanghai Ocean University and most of its key components were domestically made.

In August, during a seminar on China's scientific development, Xu Qinan, chief designer of Jiaolong, said the country will need a "spectrum" of manned submersibles and autonomous underwater vehicles to satisfy different mission needs.

For example, at a depth of about 6,000 meters, the seabed is rich in manganese ores, while on mountains that lie 4,000 meters below the ocean surface, there is a thick layer of cobalt, which is useful in the manufacture of batteries.

"If we have a good understanding of what is below the ocean surface, it will significantly increase our role in international ocean governance," he said.

In addition, Xu said self-sufficiency is also one of the main characteristics that underpins China's continuous innovation in deep-sea submersibles. In 2017, China successfully tested a submersible called Shenhai Yongshi, meaning "Deep-sea Warrior", capable of reaching a depth of 4,500 meters.

"Many people have asked me 'Why build Deep-sea Warrior when Jiaolong can go even deeper?'" Xu said. The answer is that the Shenhai Yongshi is almost entirely Chinese-made.

While much of Jiaolong's equipment was imported, about 95 percent of Deep-sea Warrior and all its core components were produced domestically, Xu said. Building the new submersible also pushed engineers to overcome major battery issues and lay the foundations for further deep-sea exploration.