August – The Expedition End is Near for Leg 1:
I can’t believe that I just had my last shift of the cruise. Time has flown by. I think it’s because I’m on the night shift, but it seems like it’s been one really long day punctuated by naps, not 9 days at sea! I’ve really enjoyed getting to see the whole process of maintaining and deploying instruments. Seeing where the data I’ve been working with comes from has been enlightening. Additionally, experiencing a research cruise and learning what a day of operations looks like is very useful for the future.
Yesterday, I was in the control van for the HPIES (Horizontal Electric Field, Pressure & Inverted Echo Sounder) dive, deploying a new instrument and recovering the old one. There are PVC arms on the HPIES that need to be in a specific orientation, and during freefall through the water column, they got knocked around. However, Jason was able to grab onto part of the PVC and move the arms back into position. It was a tense moment but I’m glad there was a quick fix.
Today, we went to Endurance Offshore to recover a BEP (Benthic Experiment Package). These packages are similar to the shallow profilers, just on the seafloor instead. There were lots of animals on the way down and on the seabed.
There was also an excess of marine snow in the water column, along with siphonophores, ctenophores, and larvaceans. Once we got to the bottom, there was a Pacific Sole underneath the hydrophone. Even when we picked up the hydrophone it didn’t move much—maybe it was confused by Jason. There was also a Giant Pacific Octopus on the anti-trawling casing of the BEP that wouldn’t move even after we shook Jason’s manipulator at it. We had to use a scrubber (normally used for cleaning instruments) to poke it and get it to move so that we could open the BEP doors. Unrelated to the dive, I also saw a small shark off the side of the boat!
Today, I was in the van during two dives to change out the Shallow Profiler Assembly (SPA) and Primary Interface Assembly (PIA) on a shallow profiler at Slope Base. The whole operation was very efficient, with the dives being only 2-4 hours long. It was great being in the van during these dives because I’m working with data from the shallow profilers for my project. The SPA and PIA had a lot of organisms living on them, including brittle stars, anemones, and crabs. One crab even squared up with Jason as if it wanted to fight! There were also pyrosomes and siphonophores (both of which are pelagic colonial organisms) in the water column.
The Shallow Profilers collect data throughout the upper 200 m of the water column. They have sensors on the science pod that travels up and down nine times a day. They collect information like temperature, salinity, depth, chlorophyll, and pH. Chlorophyll, in turn, is used as a proxy for phytoplankton. Higher chlorophyll concentrations in the water column means there’s more photosynthesis, and therefore more phytoplankton.
We are also diving down to almost 3000 m on Slope Base, the deepest dive we’ll do on this cruise. We attached a neon green plastic chicken to the undervator, a basket used for transporting instruments underwater. It was quite something to watch that chicken travel downwards into the depths. It didn’t compress much, but I guess we’ll see how deformed it becomes once it reaches the surface again!
Our Styrofoam cups also traveled to the seafloor yesterday, and they’re so small now! It’s amazing to see what the enormous pressure at depth can do to everyday objects.
August 5: Primary Node 1B Work
We are now~10 km south of Southern Hydrate Ridge preparing the Primary Node (PN1B) for recovery later in the cruise. This area is a lot closer to shore, so it took about 18 hours to transit here. The bottom is also a lot shallower—1600 meters instead of 2600 m. The seafloor still has a thick layer of sediment that is easy to kick up when Jason lands. I didn’t see much difference between this area and Axial Base, where we were previously, although that was likely just due to the location of the primary node and not the area as a whole. The primary node is where the power for the other cabled infrastructure in the area is received from, so it’s a very important piece of equipment. It’s housed in a big anti-trawling case. A bunch of crabs had somehow gotten inside the casing and were very protective of the node as we opened the doors. There were also some rockfish hanging out in the area and lots of ctenophores. A few big squid passed us by as well on the descent, and as usual, there was a lot of marine snow.
Jason had to bring a component called the Science Interface Assembly to the surface, and therefore had to securely attach to it for the ascent. There was a fairly small, compact lifting system on the unbelly of Jason attached to the node and locked into. The node itself is really heavy so it was impressive to think that with the locking mechanism, Jason could lift the node out of the water!
Some albatrosses have been following the boat. They’re such big birds, and so graceful when they fly. I have a feeling they think we’re a fishing boat and that they’re going to get some scraps! They feel kind of like bodyguards for the vessel.
August 4 – Gaining Experience
Today in the control van, I watched Jason ascend from a very long dive (about 10 hours) from a depth of about 2600 meters. The seabed was very muddy, flat, and covered in brittle stars. The equipment on the seafloor, including a CTD and secondary node, loomed out of the gloom as we got closer. There was also a dusting of marine snow lightly falling, giving the creatures on the bottom the food they need to survive.
It will be fascinating to compare this location (Axial Base) with our next location (Southern Hydrate Ridge), which lies further on the continental shelf as opposed to the abyssal plains.
I didn’t realize just how long ascending from the dive would take—I feel like it can be hard to conceptualize how deep 2600 m is (8530 feet), but when it takes about 2 hours to reach the surface, it gives you a good idea of how far down Jason really is. On the way up, we saw some squid, jellies, and pyrosomes.
I also helped with a CTD rosette today. The rosette consists of a ring of Niskin bottles and a CTD at the bottom. The Niskin bottles are used to collect water from specific depths. The bottles are open during the descent of the rosette and closed via an electrical trigger to capture water. This CTD was shallow, at only 220 m.
We collected samples for dissolved oxygen, dissolved inorganic carbon, chlorophyll, salinity, and nutrients. The bottles themselves hold 5 liters of water, which is why we are able to get so many samples. The process of collecting the samples is a pretty wet one. At the very end, the bottoms of the bottles are released, and water goes everywhere!
We visited the bridge and learned about the navigation of the ship. It’s a big job to get the vessel to remain in a precise location during the Jason dives. It was interesting to see all the different controls for the vessel and how many redundancies are needed for each system. I learned that the horizon is about 13 miles from the ship on a clear day, which is pretty far!
August 3: Adjusting to the Ship
Yesterday was spent adjusting to the motion of the ship and my new time schedule. My shift is from 0:00 to 8:00, so I go to sleep around 15:00! Having a shift at this time does mean that I get to see the stars and the sunrise, even if I am asleep most of the afternoon. Today, I am basically adjusted to this schedule. I have dinner for breakfast, breakfast for lunch, and lunch for dinner!
We also reached Axial Base yesterday. It feels a bit surreal to look out at the horizon and see no signs of land. The R/V Thompson feels more like a building to me than a boat, though, so it isn’t disorienting—just something new. It makes me think about how much of our oceans remain unexplored, and how cruises like this could easily discover something new and exciting.
Today I had my first watch during a Jason dive. Stepping into the Jason control van is like stepping into the control center for a space mission. There are so many video and diagnostic screens to watch, from cameras to navigation. I am a data logger, which means that I record when dive milestones are occurring. The dive that I watched deployed the Platform Interface Assembly on the Axial Base Shallow Profiler platform, which sits at about 200 meters beneath the oceans’ surface. Even though 200 meters might sound deep, it’s actually relatively shallow. Later today, we are doing a CTD cast (which measures conductivity, temperature, and depth) to about 2595 meters.
We also decorated Styrofoam cups to shrink down on one of the CTD casts. It’ll be a fun souvenir from the cruise and is a tradition at this point. I decorated mine with some simple images of marine creatures. I’ll keep you updated on how it turns out!
A bird also got onboard the ship! We put it in a box in the dark to keep it feeling safe and released it this morning. Needless to say, I was very confused the first time I heard that there was a bird rattling around in a cardboard box on the boat. I’m glad we were able to release it and it could fly away.
August 1 and 2: We are off to Sea
And we’re off! We left from the UW dock in the evening, opening three bridges on our way to the Ballard locks. There were lots of interesting boats and people on the water, including a pirate ship, man blowing a conch shell, and hot tub boats! There was also quite a bit of wildlife. A dock was absolutely covered in seagulls. Seals were in the locks looking for some salmon to munch. An osprey was also fishing, and we saw it catch a small fish!
We arrived at the Ballard locks, which are basically “boat elevators,” getting boats to either the lake or Sound water level. I have seen boats go through the locks many times, but I haven’t been on a boat as large as the R/V Thompson going through them. It’s a totally different experience being on the ship than just watching. It was fun to talk to people watching the boat and see how the locks operated with a larger vessel.
By this time, the sun was setting, which turned the sky a beautiful pink over the Olympic mountains. The water was calm, and we had a gorgeous view of the main basin of Puget Sound and Seattle as we headed to the dock for the night. We could see the whole Seattle skyline—the whole scene was very peaceful.
This morning, we toured the boat and learned about the ROV Jason. We’ll be spending lots of time in the control van, logging data and taking pictures of the dives. I’m looking forward to all the weird marine life and geological features we’ll see on our first stop, the underwater volcano Axial Seamount! Now, we’re on a 40-hour transit to get there. This will be a good time to adjust to ship life and shift schedules. What a great start to our adventure!