Biju Dharmapalan
After successful space missions, the Indian scientific community is looking for the next big breakthrough, exploring the deep oceans. Why is the government giving high impetus to this mission?
Oceans cover 70 percent of the Earth’s surface, yet their depths remain largely unexplored. Scientists estimate that 90 to 95 percent of the deep sea is still a mystery. We know more about Mars and the Moon than our own planet’s ocean floor.Despite twelve astronauts having spent three hundred hours on the moon, just three have ventured to Challenger Deep-the deepest point on Earth’s ocean floor-to explore it. The deep ocean is truly the planet’s final frontier and unexplored territory.
The term “deep sea” varies in meaning based on the context. To fishermen, it refers to any ocean part beyond the shallow continental shelf. For scientists, the deep sea is the lowest part of the ocean, lying below the thermocline-where sunlight no longer affects the water temperature-and above the sea floor, deeper than 1,000 fathoms (1,800 meters).The deep ocean is a realm of extreme conditions. Its immense pressure, perpetual darkness, and frigid temperatures make it one of the most hostile environments on Earth. The deep ocean holds mysteries and treasures that could redefine our understanding of life, geology, climate, and the very fabric of our planet.
It’s difficult to explore the depths because they are eternally dark, extremely cold (between 0 degrees C and 3 degrees C below 3,000 meters), and under high pressure (15750 psi or over 1,000 times higher than standard atmospheric pressure at sea level).The Challenger Deep in the Mariana Trench is the deepest part of Earth’s oceans, reaching 10,994 meters (36,070 feet or nearly 7 miles) below sea level. This part could even hold Mount Everest.
Specialised instruments have been created to investigate this frigid, obscure, and highly pressurised setting. Deep sea exploration is a multifaceted undertaking encompassing various fields such as oceanography, biology, geography, archaeology, and engineering. Similar to space travel, deep-sea exploration necessitates novel tools and technologies. While space is a cold vacuum, the ocean depths experience low temperatures and significant levels of pressure. Moreover the, saltwater is both corrosive and conductive.
Manned and unmanned missions carry out deep ocean studies. Manned missions use submersibles, specially designed vehicles capable of withstanding the extreme conditions of the deep sea. India’s first deep ocean mission, Samudrayaan Mission, aims to develop a self-propelled manned submersible to carry three human beings to a water depth of 6000 meters. Unmanned missions employ remotely operated vehicles (ROVs) and autonomous underwater vehicles (AUVs), equipped with sensors and cameras, allowing scientists to study the deep sea remotely.
One of the objectives of deep ocean missions is discovering new species and ecosystems. The deep sea is home to a staggering diversity of life, much of which remains undocumented. The deep ocean’s unique organisms might hold the key to new biotechnological applications, from novel pharmaceuticals to industrial enzymes.
The ocean is a major carbon sink, absorbing approximately a quarter of the carbon dioxide emitted by human activities. However, carbon sequestration processes in the deep ocean are complex and poorly understood.By studying deep-sea sediments, currents, and biogeochemical cycles, these missions will help scientists predict how the ocean will respond to climate change.
The deep ocean also harbours vast mineral and energy resources that could be pivotal for future economic development. Polymetallic nodules, rich in manganese, nickel, and cobalt metals, litter the ocean floor. These metals are critical for manufacturing batteries and electronic devices, making deep-sea mining an attractive prospect.
Though exploring the deep ocean floors would provide new insights, care should be taken to avoid the destruction of the ocean environment due to various deep ocean missions. Wherever humans have ventured, they have polluted the environment, whether in outer space or on this planet. The same should not happen to deep ocean missions. The deep ocean should be declared a protected area for humanity that needs international collaboration, similar to space research. Several initiatives like Proteus Ocean Group (POG), a private sector social enterprise, have started building the first International Space Station of the Sea to be a collaborative global platform for researchers, academics, government agencies, and corporations to advance Ocean science.
(The author is an adjunct
faculty at the National Institute of Advanced Studies, Bangalore)