Mission & Project Info | NOAA’s Aquarius Undersea Laboratory
Mission Blog

The Aquarius Habitat supports Saturation Divers at a depth of 47 Feet Sea Water. The commercial diving industry conducts saturation diving to much greater depths utilizing chambers on board a Dive Support Vessel (SDV) and a Diving Bell for lowering divers to the sea floor. One of the largest and most modern saturation diving systems in operation today is the DSV Skandi Arctic. Aquarius Reef Base’s Operations Director, Saul Rosser, also happens to have been heavily involved in the design of this system which can take divers to 350 Meters Sea Water (1,150 Feet Sea Water).  Discovery Science recently produced an episode of their Mighty Ships series on the Skandi Arctic and it can be viewed at the following link:

http://watch.discoverychannel.ca/mighty-ships-/mighty-ships-season-4/mighty-ships-4-skandi-arctic/#clip426506

By Sebastian Engel

Video by Sebastian Engel, edited by Danielle Dixson

Today marks the 8^th day of our mission and all is going according to plan.  We’ve finished collecting data and are now taking down our experiment.  This is by far the most labor intensive part of our mission because it involves breaking down our experimental cages and cleaning up the reef.  Each cage, measuring 2m x 2m x 1.5m, consists of a stainless steel frame that is covered with plastic coated chicken wire.  The cage frame is anchored into the substrate with 12 inch spikes and the chicken wire flanges are secured with hundreds of fencing nails.  To remove these cages we use large metal shears and crow bars.  We found it easiest to do this work without our fins because we get better leverage standing up and are able to walk the heavy cages to central sand patches were we consolidate all material.   

The habitat technicians and the rest of the Aquarius Reef Base team play a critical role in keeping us safe and helping us with our clean-up effort.   After each cage is removed, surface support divers meet us at the bottom and take all caging material up to the surface, load it on their boat, and transport it back to shore.  Under water, the Aquarius habitat technicians coordinate all our diving activities with the surface support team.  To communicate with Aquarius we dive into a waystation that is positioned at our research site and equipped with a microphone, a speaker, and air-fill equipment.    While we discuss our diving activities and fill our SCUBA tanks, we frequently drink bottled water to stay hydrated.  

                The Aquarius habitat is a great diving platform because it allows us to conduct working dives up to 8 hours every day without ever having to go to the surface.  After each dive we head back into Aquarius to eat, discuss work, and even take a nap, before going back out for our next dive.  Spending so much time under-water is not only a lot of fun but also exposes us to sea life not frequently seen while SCUBA diving from the surface.  Recently we encountered a Hawksbill Turtle (Eretmochelys imbriocota) feeding on a sponge (Geodia neptuni).  Surprisingly, this turtle continued feeding and was not bothered by our presence.  It appears that spending eight hours every day working at our site makes us part of this amazing underwater world!

See Sebastian and Danielle’s video here:  http://www.youtube.com/watch?v=2ECHJ9bGkFc

By Doug Rasher

Today was a great day out on the reef. We rolled out of bed at first light, brewed up some coffee and ate our oatmeal, and began our day of data collection on the reef well before most people head out to work at their normal jobs on land. As we swam across the reef in the morning, we noticed the daily activity of the reef had already picked up by 8am. We passed a turtle grazing on a large sponge on our morning commute along our excursion line from the habitat to our work site, and we were welcomed at our work site by grouper, permit, snapper, barracuda, and nurse sharks looking for their breakfast. After checking in with the habitat on the intercom at the waystation (where we can also re-fill our SCUBA tanks!) we began our work. Today’s work entailed removing and dismantling some of our cages that have housed seaweed-eating fishes over the last 10 months, deploying cameras in these plots to observe grazing on the seaweeds that have been growing in these cages, and photographing corals inside other cages to track changes in coral growth over time. We spent 6 hours on the reef, so we were ready for a hardy dinner upon our return. However, the day was not over….

After dinner, we anxiously waited for dark to set in. We planned for a 2 hour night dive, and couldn’t wait to get out there. Our research goal for our night dive was to check inside each remaining cage in our experiment and count the number of nocturnal creatures residing in our cages. This is important because there is a complete shift in reef communities between day and night. Because it’s convenient to work during the day, we scientists pay most attention to the day-time reef community. But with the use of Aquarius, we can go out for long excursions at night and determine if nocturnal animals are having an impact on our study.

As we set out on the night dive, we were surrounded by the glow and deep hum of the habitat, but this soon faded away to darkness as we worked our way over the crest of the reef. We swam slowly down our excursion lines, only able to see as far as our torches would permit. With neutral buoyancy, it really felt like we were in outer space. After 2 hours, we completed checking on our cages – no nocturnal creatures to speak of, with the exception of the occasional brittlestar. Good for our experiment. At the waystation, we shut our torches down, and waved our arms around to see the bioluminescent plankton flicker in the water – pretty amazing. We radioed to the habitat that we would return home. As we approached the glow of the habitat in the surrounding darkness, it felt like our return to the mothership after an expedition on a foreign planet. This was interesting because it made me realize that despite our fascination with outerspace, there’s so much left to explore right here in our innerspace.

We’ve been living under the sea for almost 4 days now and things are going really well.  But, we are still living under the sea and things do break.

The first night we were here, it was quite warm.  It was about 82 degrees Fahrenheit which is warm enough to make you sweat a little bit at night.  James and I (the two Habitat Technicians) spent the second day investigating the cooling system and isolated the problem to a solenoid valve in a cooling unit we call the ‘air handler’.  This is an auxillary cooling unit which works in conjunction with the three primary Habitat Condition Units (two of which are in the main lock and one of which is in the entry lock). 

The Air Handler, like the HCUs, blows habitat atmosphere over a set of coiling coils which are supplied with a chilled water-glycol solution from a chiller on the baseplate outside the habitat.  The valve that James and I found to be faulty supplies water-glycol to the air handler coils and the actuator was unable to open it.  Once we realized what was going on and determined that we would neither electrocute ourselves nor flood the habitat with water-glycol by fixing it, we removed the actuation motor and used a plastic zip tie to hold the valve open.  While this is clearly a temprorary solution, by day 3 of the mission we had full cooling power and as I write this the habitat is a refreshing 77 degrees Fahrenheit.

Since we spend a lot of the day working in the warm moist Wetporch, it is wonderful to come into a cool and dry Main and Entry Lock.

Thanks for following along.

Saul