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Alvin is the only manned deep-sea submersible vessel in the United States. A little while ago, I traveled to Massachusetts for a conference at the Marine Biological Center in Woods Hole, and got the chance to sit in a model viewing port of Alvin. See the pictures from my last blog post here. The idea to perform deep-sea research in a manned vessel was proposed by geophysicist and oceanographer Allyn Vine at a scientific meeting in Washington, D.C. in 1956. The first version of Alvin was then designed by engineer Harold Froelich and produced by General Mills for half a million dollars.

Alvin was first used for scientific observation and sample collection back in 1964. Its small size – it can only fit 3 people – and rounded shape make the vessel easier to maneuver and stronger against the crushing pressures at the bottom of the ocean. Alvin was updated in 2002 to increase the number of windows from 3 to 5 and withstand pressures that make it safe to dive down 6,500 meters. Dives performed with Alvin can last up to 10 hours, if needed. A number of deep-sea discoveries wouldn’t have been possible without this amazing piece of technology. I was also enthused to find out that the titanium metal pieces of the spherical shell were shaped in Wisconsin – my current home!

Woods Hole Oceanographic Institution (WHOI) is the non-profit organization that maintains Alvin. The organization hires engineers, technicians, ship crew, and scientists, but also works in conjunction with MIT to offer degrees and hosts a variety of student programs. Some topics researched by WHOI include earth science, marine policy, and climate change. If you’re interested in ocean life, deep sea dynamics, or other similar themes, attending MIT would be a great first step to gaining access to WHOI and eventually journeying on Alvin.

Alvin’s ability to host crew members on its expeditions to the bottom of the ocean is beneficial in that it enables scientists to pick out the specific locations that samples are collected. The one-of-a-kind deep sea vessel contributed to the discovery of hydrothermal vents at the bottom of the Pacific and Atlantic mid-ocean ridges. Alvin has also photographed wreckage from the Titanic and helped to examine underwater impacts of the Deepwater Horizon oil spill disaster.

I skimmed a handful of studies that incorporated data from Alvin to provide a wide snapshot of the research that has been completed. Here are some interesting studies that wouldn’t have been possible without Alvin:

• The first study I found used underwater imagery and biological observation of things like depth and substrate type to learn about seafloor community variation in old underwater volcanoes and nearby valleys in the North Atlantic Ocean. A poster containing a summary of the study can be found here.

• Another study analyzed methane-producing bacteria from a soil core sample at a hydrothermal vent in the Gulf of California collected by Alvin. The bacteria, once isolated, had an optimal growth temperature of 85 degrees Celsius and was labeled as a strain of Methanococcus.

• In 1987, two biologists at WHOI published a study on macrofaunal colonization of changing deep-sea habitats and the structure of communities living at or within the ocean floor. The authors concluded that the 3 most important factors in deep-sea community structure are:

1. Spatial fluctuations of organic input in ecosystems with low productivity
2. Unpredictable, small-scale, and distinct changes in a constant environment
3. Few limitations to population dispersal along the sea floor

 

Material from dead plants or animals becomes more important in parts of the ocean that are very deep and far from shore. Ecosystems can also vary immensely within very small ranges, so the presence of successful scavenging fish, for example, limits population development that would normally occur around an organic source (i.e. a dead carcass). The third point is most difficult to explain. It implies that the deep sea supports never-ending population growth, however, the resources in the deep sea limit that ability. In order to study the variety of organisms that occupy deep sea sediment and what kinds of organisms might thrive there, many more soil samples over a broader range of the sea floor would be needed.

That’s all for now. If your dream is to learn about the deep sea, I hope this article showed you that your dream is possible. Otherwise, how did you come to learn about the deep sea? Did you ever hear of Alvin? Tell me in the comments!