By Anne Hartwell
Approximately 71% of the Earth’s surface is underwater, and more than 80% of what is underwater, is unexplored. The massive expanse of oceans unvisited is not surprising when you consider the cost, time, and challenges of exploring highly pressurized parts of the Earth from being under the weight of the entire ocean. When a vessel and research crew do have the opportunity to be in the field, they are able to get the most detailed view of the alien landscape deep beneath the surface with the aid of underwater robots. Three examples of underwater robots are Human Occupied Vehicles (HOV, aka submarines), Remotely Operated Vehicles (ROV), and Autonomously Operated Vehicles (AUV). Each type of robot has advantages depending on what goals are needed to be achieved on a given research expedition. For instance, HOVs enable researchers to experience the deep sea with their own senses, ROVs can stay on the bottom for days at a time, and AUVs roam a pre-determined course and operate independently of the research vessel. Although the use of HOVs is expensive, and sometimes deemed impractical as remote and autonomous technologies advance, the experience has an irreplaceable effect on the scientists themselves. For the participants, HOV dives can deliver a perspective of the deep-sea environment absent from textbooks and can plant questions that will fuel research interests for years to come.
I had the privilege of participating as an observing scientist on an HOV dive in 2014 while on a research vessel in the Pacific Ocean. At 7:50 A.M., the HOV pilot, a second observer, and I, all crawled into the 1.8-meter diameter sphere section of the submersible. After being sealed tightly inside the HOV, we were launched from the ship deck. As the submersible descended from the sun-lit surface into the water column, the water changed from blue to green to total darkness. As we moved through the darkness, the disturbance to the water column caused the bioluminescent organisms to glow like stars in the sky. When we arrived at the seabed almost two hours after leaving the surface, the pilot illuminated our surroundings with the HOV’s bright lights. My jaw dropped as I saw bright oranges and yellows through the porthole. I had never in my life imagined such a colourful community so far from the reaches of sunlight. It was at that moment that my perspective of the depths of the ocean completely changed. I could practically feel the rush of research questions and new ideas fill my brain.
Participating in an HOV dive was a privileged and unbelievable opportunity for which I will forever be grateful. It made me a better scientist by revamping my perspective of the ocean and opening my eyes to the types of questions about the deep that remain to be answered.
About the author:
PhD Student University of New Hampshire CCOM/NOAA JHC