New technology such as the Scantrol Deepvision System is being used in ocean research. It takes photographs of and measures fish as they swim through the tunnel. There are only a few in operation and it can be modified to 3000m depth.
“India has completed the mapping of this region and made a quantity assessment, but it is a question of how sustainably, safely and economically you can mine it.”
“India is rapidly gearing up its blue economy and its ocean sciences research,” says Hyderabad-based Dr Satheesh Shenoi, director of the Indian National Centre for Ocean Information Services, and co-chairperson of the Second International Indian Ocean Expedition (IIOE-2) steering committee.
“We are building more ports and harbours so that many more goods can be transported by ship, which is far more cost effective, with fewer carbon emissions. India is also looking at the resources in the oceans, including oil and gas and potential medicines. We recognise the critical role of our oceans in climate change, and are investing substantially in ocean research and ocean observation.”
Monsoon winds
Sailors in the Indian Ocean have always known that the monsoon wind pattern changes twice a year, but investment in research into these winds and the many complex dynamics of the Indian Ocean is only fairly recent. With the Indian Ocean warming faster than any of the world’s other oceans, the IIOE-2 is very much part of the shift towards conducting scientific research in the region.
Why the Indian Ocean is warming
Shenoi suggests two possible explanations for Indian Ocean warming that require further research:
1. The Indonesian throughflow from the Pacific has increased, bringing more of its warm water into the Indian Ocean.
2. The westerly winds over the equatorial Indian Ocean are becoming stronger, strengthening the downwelling conditions, and leading to the warming of the upper ocean.
More than 40% of the world’s population lives in countries prone to cyclones, floods and droughts along the Indian Ocean, so it is important to understand how the climate affects people and their livelihoods.
A key question is how Indian Ocean warming influences the monsoons.
“We don’t know the answer to this yet,” Shenoi replies. “Some of the published research indicates that warming is happening more at the subsurface layers, in which case it won’t immediately affect the atmosphere. But is it a matter of time before the ocean transfers the heat to the surface? Increased surface temperature is certain to affect the African and Asian monsoons; the entire regional pattern could change, with either increased or decreased rains. All this will directly affect the Indian Ocean populations and their livelihoods.”
Macroeconomic level: Looking to the ocean
At a macroeconomic level, India is a major importer of oil and it is looking to the ocean for an alternative, with the discovery of solidified methane gas deposits on the ocean floor.
“India is one of the pioneer investors in future ocean technology, but it might take another decade to develop the technology to extract these deposits without losing the methane,” Shenoi explains. “Another example is the technology required to mine the deposits of manganese, zinc, cobalt and several other metals at a depth of about 500 metres in the central Indian Ocean.
“India has completed the mapping of this region and made a quantity assessment, but it is a question of how sustainably, safely and economically you can mine it. These metals are used to make alloys for many purposes – from engineering to technology. Assessments predict that these will run out on land in about 30 years, so these ocean deposits will become a critical resource. In all forms of ocean management – from conservation to mining – we need to think several decades ahead. It’s a very short period of time in the greater scheme of things.”
http://www.incois.gov.in
Interconnected ocean power and its influence on the Earth’s rotation
Massive exchanges of water between the Pacific and Indian Oceans emphasise the interconnectivity of the world’s oceans, with significant climate-related implications.
Dr Satheesh Shenoi was part of a group of scientists from France and the Indian National Centre for Ocean Information Services (INCOIS) working on this research. Their findings were published in April in the journal Nature Communications, in a paper titled: Basin-wide Sea Level Coherency in the Tropical Indian Ocean Driven by Madden–Julian Oscillation. (Rohith et al. https://www.nature.com/articles/s41467-019-09243-5)
Sea level rise or fall of ~4cm
Excerpts from this paper read as follows: During the months of December to April, the Indian Ocean routinely gains or loses ~three trillion tons of water from the Pacific Ocean every ~30 to 80 days accompanied by a sea level rise or fall of ~4cm, which is ~ 30% of the total sea-level change during the period. This process is driven by intense winds hovering over a very small area in the eastern Indian Ocean. This intense wind is associated with a little-known tropical weather phenomenon known as Madden-Julian Oscillation (MJO).
Effect on the GPS
The rise and fall of the sea level in the Indian Ocean leads to mass exchanges between the Indian Ocean and the Pacific Ocean. Such large mass exchanges are known to influence the polar motion of the Earth and the length of the day, the variability of which is of utmost importance to the accuracy of the Global Positioning System (GPS).