Naomi Wharton Blog Leg 2

Sunset view from the starboard deck, minutes before a tiny green flash. Credit: N. Wharton, University of Washington; V24.
A playful scene from our tour of the Atlantis engine room. Credit: N. Wharton, University of Washington; V24.

August 25, 2024

For my final blog post, I wanted to reflect on the elements of VISIONS that have made my week-and-then-some on Atlantis an over-the-top experience.

Everyone on Atlantis has been extraordinarily kind. Going into the cruise, I wasn’t sure exactly what my role would be. As a VISIONS student, I came to learn about ship operations and experience sea-going observational oceanography first-hand. Yet, as a graduate student with my own research underway, I was not working on a VISIONS-specific student project nor enrolling in the corresponding class this fall.

What had the potential to be a week of ambiguity instead became a week of opportunities. My fellow VISIONS students welcomed me into the rotation of shifts in the Jason control van, where we witnessed and played a small part in scenes unfolding hundreds or thousands of meters below us. Leg 2 Science Team and UW/APL Engineering Team members gave me a seat at their table (literally) where I could watch decisions being made in real time as tall waves, strong currents, technical difficulties, etc., necessitated hour-by-hour (or minute-by-minute) rearrangements of an already tight 24/7 schedule. Laura and Anna went above and beyond in explaining and sharing their science with all.


Center console of the Atlantis bridge and view of the ocean beyond. Credit: N. Wharton, University of Washington; V24.

The crew of Atlantis have been amazing. Sarah and Ben in the galley knew my name, face, and specific dietary needs from our first meeting on Day 1. We were treated to a fantastic tour of the ins and outs of the engine room on Thursday. The Chief Mate toured us through the bridge yesterday and answered all of our questions for over an hour while we took in breathtaking views of the vast ocean sweeping out in all directions.

SSSG Ella gave us our first introduction to the ship, walked us through the procedures for XBT and multibeam sonar observations, and even personally tinkered with the wiring in the ceiling of my sweltering berth when the room heater was stuck on full blast.

In such a short time, I have been able to experience many of what I imagined to be the wonders of being at sea. In addition to the multitude of odd creatures viewed through Jason’s cameras, I have seen whale spouts in the distance, the elusive ocean sunfish (Mola mola) basking in the sun, flocks of black-footed albatrosses, and a small sandpiper blown far offshore onto our decks that Engineer Trina Litchendorf rescued and cared for until it could be released back in Newport.

Bright moonlight reflecting off the water. Credit: N. Wharton, University of Washington; V24.

I have seen the Milky Way in the dark night sky, expansive watercolor-worthy sunsets spanning the full horizon, the glowing spectacle of Jason rising from the depths of an inky black ocean, and even the tiniest green flash. It has been an experience like no other – thank you to all I shared the journey on Atlantis with as well as to those who made it happen!

Jason is visited by a crab while collecting push cores at Southern Hydrate Ridge for Dr. Laura Lapham. Credit: UW/NSF-OOI/WHOI; J2-1638; V24.

August 22, 2024

We returned to Oregon Offshore late last night. Although the currents were still relatively strong, Jason was able to complete the previously aborted dives to recover and redeploy the science profiling pod from the Shallow Profiler Mooring. As we transited back to Southern Hydrate Ridge during the second half of my morning shift, I helped Dr. Laura Lapham and her graduate student, Anna Hildebrand, assemble push core tubes for sampling with Jason.

Dr. Lapham and Anna are on VISIONS to study the methane-consuming microbes that live in deep sea sediment near methane seeps. On Wednesday, they sent 18 tubes down in a basket on Jason’s “porch” in order to take sediment core samples at Southern Hydrate Ridge. Each tube has a specialized T-shaped handle that Jason can grip with a manipulator arm in order to lift the tube off the porch, press it down into the sediment, and return the filled tube to the porch.

VISIONS’24 graduate student Anna Hildebrand holds up a push core sediment sample containing a visible layer of microbial mat. Credit: N. Wharton, University of Washington; V24.

After Laura and Anna worked through the night to process and store the first 18 tubes of sediment, several of us helped them to tape up and attach handles to a second set of 18 tubes to be sent down with Jason at 1 pm.

One aspect of VISIONS that has been jarring for me is the ongoing 24/7 schedule of science operations. It makes sense logistically given the expenses of running such a large vessel; you want to accomplish all of your tasks as quickly as possible. Weather and sea state are constantly changing the planned order of operations, and Jason dives can last quite a while depending on the target depth. Several of the Science Team members are on 4 AM – 4 PM shifts or vice versa, and I suspect that Dr. Lapham and Anna have barely slept at all on the days surrounding their dives. Despite understanding the logic, my body has not quite adjusted yet to the 8000-1200 and 2000-2400 shifts that make it impossible to sleep for eight hours straight. I am definitely looking forward to a long sleep upon our return.

After transiting to our final unique site of Leg 2, Slope Base, we began Dive J2-1639 to test the Deep Profiler dock during my evening shift. At 2900 m, the seafloor at Slope Base is much deeper than our previous stops. The descent alone took Jason two hours! The goal of the dive was to determine what component was causing a large ground fault – the mooring base or the cable attached to it. Upon arrival, we found the mooring base covered in a layer of hair-like green algae. After a few unsuccessful attempts to grip the attached cable in order to unplug it, Jason whipped out a white scrub brush and scraped away some of the algae. Although I’d seen Jason’s manipulator arms in use quite a few times by then, there was something about the sight of Jason performing such a normal, human-like task that gave me a laugh. The scrubbing did the trick; Jason completed the rest of the test without incident.

Jason scrubs the Deep Profiler mooring base at Slope Base. Credit: UW/NSF-OOI/WHOI; J2-1639; V24.

Jason’s next task was to locate the Deep Profiler itself. The OOI Deep Profilers are “wire-following vehicles” that travel up and down along a mooring cable, making observations from a depth of 2900 m up to around 150 m. This particular Deep Profiler had gone offline in February 2024 with a last reported depth of 770 decibar, or approximately 770 m depth. Although we suspected that the vehicle would still be sitting around 770 m, the Jason team made sure to keep the mooring cable within sight throughout the ascent so that they could locate the vehicle visually. Jason was still ascending at the end of my shift, so I was left in suspense as to the true depth of the profiler. After a post-shift bowl of ice cream that has become my routine, I headed off to get some sleep.

August 21, 2024

Translucent methane ice seen at Southern Hydrate Ridge. Credit: UW/NSF-OOI/WHOI; J2-1633; V24.

Midway through the week already!

Mosquito Deployment. Credit: UW/NSF/OOI/WHOI; J2-1633; V24.

Jason descended at the Southern Hydrate Ridge site for Dive J2-1633 this morning at 0548, so I took over as video logger mid-dive when I arrived for my 0800-1200 shift. The dive began with the deployment of the MOSQUITO benthic fluid flow sampler and two other uncabled instruments. All three had been transported to depth in Jason’s “undervator,” which is essentially a large basket that is latched beneath the ROV. It was pretty surreal to see the MOSQUITO instrument sitting on the seafloor at 780 m depth after having helped assemble it on the ship just yesterday. Jason then retrieved older (2023) versions of the uncabled instruments from the seafloor and secured them in the undervator for transport back up to the ship.

A colorful worm organism spotted at the Southern Hydrate Ridge site. Credit: UW/NSF-OOI/WHOI; J2-1633; V24.

I appreciate that while the main objectives of Jason dives on the VISIONS cruise are primarily to perform maintenance on the Regional Cabled Array, they also take every opportunity to document new or unusual (or both) marine life they encounter in the deep sea. This really speaks to how unexplored the deep sea is relative to other habitats on Earth; each shot could contain something never seen before. When serving as event logger, we record any and all notable biology sightings in the dive log for later reference. On this morning’s dive, after lifting up one of the older uncabled instruments, we spotted a worm-like creature with brilliant red and purple coloring. As it wriggled along the newly exposed sediment, we stopped for a few minutes to take 4K footage and high-resolution images before continuing with the retrieval.

The dive continued with a survey of the Einstein’s Grotto and Smoky Caverns areas of Southern Hydrate Ridge to assess if there were still active bubble plumes in the area. After passing along ridges covered in white and grey microbial mats, we came across a section littered with translucent lavender rocks. These were actually chunks of methane hydrate – ice with methane molecules trapped within the crystal lattice. We could see methane bubbles periodically rising up from a dark crevice in the seafloor and sliding along a rocky overhang covered in methane hydrate before ascending toward the surface as part of a gas plume. Illuminated and sparkling in Jason’s bright lights, the scene was strikingly beautiful.

August 20th, 2024

Multibeam sonar image showing a bubble plume rising from the seafloor near the Southern Hydrate Ridge site. Credit: N. Wharton, University of Washington; V24.
VISIONS’24 graduate student Anna Hildebrand releases an Expendable BathyThermograph (XBT) probe into the water. Credit: N. Wharton, University of Washington; V24.

Today we transited from Oregon Offshore to Southern Hydrate Ridge, our third site of Leg 2, during my morning watch. Prior to departure, we released an Expendable BathyThermograph (XBT) probe from Atlantis in preparation for performing a multibeam sonar bathymetry survey during our transit. Multibeam sonar estimates the depth of the seafloor by emitting several sound pulses and measuring the amount of time it takes for the pulses to reflect off the bottom and return back to the ship. To get accurate measurements, it is important to know how fast the pulses are traveling through the water – this is where XBTs come in. An XBT is an approximately foot-long probe that is tipped out of a gun-like device into the water. The probe is connected to the gun by an extremely long and thin copper wire, which relays temperature information back to the ship as the probe sinks. Combined with an estimated sinking rate based on the known weight of the probe, the XBT provides enough information to create a temperature depth profile of the water column. The temperature profile together with salinity estimates can be used to create an approximate profile of how the speed of sound varies with depth in a particular location. I had just learned about XBTs a few months ago in class, so it was cool to see one in action. Unfortunately, XBTs become ocean trash after only a single use (hence “expendable”); the copper wire is cut and the probe is left on the seafloor. While XBTs are still useful for estimating localized sound-speed profiles as we did today, I was also reminded of the significance of newer profiling technologies like Argo floats, which can record around 150 temperature profiles over the lifetime of a float. 

Flock of black-footed albatross spotted at the Oregon Offshore site. Credit: N. Wharton, University of Washington; V24.

While out on deck for the XBT, we spotted two birds soaring low around the ship and occasionally dipping towards the water and back up again in a smooth arc. Their coloring and long, thin wings were quickly identified by the group as indicative of the black-footed albatross, which was exciting to me as an amateur birder. This reminded me of a large flock of birds I had seen hanging around the ship yesterday but had been unable to identify at the time using my bird identification app (Merlin Bird ID by the Cornell Lab of Ornithology – highly recommend!). After consulting with others and my fuzzy photographs from the day before, we concluded that they had likely all been black-footed albatrosses!
We began our transit after observing the sound-speed profile from the XBT. With the multibeam sonar pinging loudly throughout the ship every few seconds, we gathered in the computer lab to watch for signs of bubble plumes in the incoming survey images, as the main goal of the survey was to detect and map locations where methane gas was actively bubbling up from the seafloor. Once we got to the right spot, the gas plumes were surprisingly easy to spot in the survey images. These methane seeps, sometimes referred to as “cold seeps” because they are not hot like  hydrothermal vent systems (although they are still warmer than the ambient seawater), are formed when methane that has built up from the decomposition of dead organic matter escapes through fissures in the seafloor. Like hydrothermal vents, these methane seeps fuel communities centered around chemosynthetic organisms. As there are vast stores of methane trapped beneath the seafloor, these methane-consuming microbes play a key role in curbing the amount of methane that is released into the atmosphere.

August 19th, 2024

Jason glowing beneath the surface as it begins its descent toward the Offshore Shallow Profiler Mooring on Dive J2-1628. Credit: N. Wharton, University of Washington; V24.

This morning began with a low point followed by a high point. Seasickness hit me in full force this morning after showering. It is now clear that my immunity to carsickness does not apply to the sea, even with the aid of meclizine. There are times when the continuous rocking is nice, almost like riding on a carousel horse. At other times though, particularly when in my windowless berth below the main deck, it feels more like being gently but unceasingly shoved from side to side. Eventually I managed to crawl out from below and into the main lab for my 0800-1200 shift. Almost immediately, I heard the word going around – whales spotted off the bow! Several short flights of stairs later, I was greeted by the surreal sight of whale blows on both sides of the ship. Though I only caught one actual glimpse of a whale as it surfaced, the distinctive white puffs visible every few seconds in the distance were unmistakable.

From left to right: V24 Science Team members Alex Rose and Andrew Paley and V24 student Leo Couchon assemble a MOSQUITO benthic fluid flow sampler (MOSQUITO). Credit: N. Wharton, University of Washington; V24.

One thing that I have observed while at sea is that the planned order of operations is entirely at the mercy of the ocean. After transiting in the morning to the Oregon Offshore site, our second site of Leg 2, the plan was to deploy the new benthic experiment package (BEP) on the first Jason dive at the site. Upon arrival, the sea state was determined to be too heightened to deploy the relatively wide and bulky BEP, so plans were changed to instead start with deployment of the LV01C junction box. This in turn required rearranging the placement of equipment on the deck so that LV01C was ready to be latched beneath Jason.

After some afternoon birdwatching on the deck, I had the chance in the evening to help construct a benthic fluid flow sampler, known as a Multiple Orifice Sampler and Quantitative Injection Tracer Observer (MOSQUITO), that was being assembled for deployment the following day. MOSQUITOs are uncabled instruments that measure fluid flow at the surface of the seafloor sediment via osmotic pumps. Several needles of different lengths are rigged pointing downwards from the top of the MOSQUITO frame. After the device is placed on the seafloor, Jason can pull a rope to free the center platform to fall down and plunge the needles into the sediment (hence the name “mosquito”).

Offshore Shallow Profiler Mooring straining against strong currents. Credit: UW/NSF-OOI/WHOI; J2-1628; V24.

By my 2000-2400 shift, the sea state had not improved enough to deploy the BEP, so the dive plans had changed again. The new main objective of Dive J2-1628 was to recover the science profiling pod from the Oregon Offshore 200 m Shallow Profiler Mooring. As Jason began descending from the surface, I slipped onto the deck and caught the striking sight of Jason glowing brightly amidst the otherwise pitch-black waves. Midway through the descent, I switched into the position of event logger in the Jason control van, entering notable events from the dive into software called Sealog. My role was short-lived, however, as it was soon determined that currents at the 200 m depth of the mooring were too strong to perform the recovery; while Jason managed to grab hold of the mooring, it couldn’t maintain the grip. Although it was unfortunate that the dive had to be aborted, the sight of the mooring straining against the flow was very interesting from a physical oceanography perspective! Strong currents like these “blow down” the profiler, pushing it deeper and in the direction of the current. I don’t know the cause of these events but would be curious to see how they relate to variability in current velocities both closer to the surface and deeper down as observed by the Deep Profilers.

August 18th, 2024

Jason lowered over the side of Atlantis with the new ZPLSCB101 bio-acoustic sonar latched below for Dive J2-1622. Credit: N. Wharton, University of Washington; V24.

The adventure begins!

VISIONS’24 will include a lot of new experiences for me. During my time as a physical oceanographer, I have worked with data collected by satellites and by uncrewed surface vehicles, but I have never been a part of the data collection process. This will be my first time out to sea on a research vessel. This will also be a deep dive into the science that takes place at the seafloor, as my focus is typically on processes occurring at the ocean surface. I admit that I am nervous going in – though I am lucky to have always fared well in the past regarding carsickness, I have no idea whether that will translate to motion at sea.

We arrived in Newport yesterday afternoon around 2 pm after a long six-hour drive from Seattle. As we drove over the Yaquina Bay Bridge, I heard the others in the car exclaim as they spotted the Atlantis docked at NOAA Newport. After passing through the security gate, we were given the all-clear to drive up the dock and park right next to the ship. With the Atlantis looming above, we unloaded our luggage and then boarded the vessel for the first time. We were introduced to the crew and taken on a tour to important stops like the galley and laundry room. After dinner and a beautiful sunset view from the deck, the long hours of driving and little sleep the night before finally caught up to me.

After safety drills this morning that included learning how to put on a full body immersion suit in an abandon ship scenario, we departed from the dock at 12:30 pm on Saturday. We were greeted by expansive beach and mountain views as we left Yaquina Bay. We also noticed a small boat following behind us. This is apparently standard protocol for leaving a harbor – a pilot with specific knowledge of local waterways and hazards within will navigate the ship out of port and then return via a second ship. This process involves the local pilot transferring between the moving ships via a rope ladder!

Jason plugging in the newly deployed Benthic Experiment Package (BEP) LJ01D at Oregon Shelf as part of Dive J2-1623. Credit: UW/NSF-OOI/WHOI; J2-1623; V24.

The experience I was looking forward to the most today by far was getting to interact with the ROV Jason. After an introduction to Jason while it was on deck and a tutorial on control room operations, it was time for the ROV to embark on its first dive of Leg 2, at the Oregon Shelf site. As I was not assigned to the first watch, I found a spot on the 01 deck from which I could get a clear view of Jason being lowered into the water with a zooplankton sonar instrument (ZPLSC) latched beneath. Afterwards I watched the live camera feed from the control room and elsewhere on the ship as Jason worked to detach cables from ZPLSC-2023 and plug them into ZPLSC-2024. This required first removing some of the large anemones that had covered the ZPLSC-2023 frame over the past year.

Jason attempts to dislodge a log covering cables at the Oregon Shelf site. Credit: UW/NSF/OOI/WHOI; J2-1624; V24.

I had my first watch shift in the Jason control van today from 2000-2400 during which I served as the video logger. This purpose of this dive was to deploy a Benthic Experiment Package (BEP) at the Oregon Shelf site. This was incredibly cool – as the control room monitors displayed multiple camera feeds coming from cameras on Jason, I captured still images of the newly deployed BEP from the science camera feed. During the second dive of my shift, the Jason team examined a log that had settled on top of some cables at the site. It was interesting to watch the Jason engineers brainstorm ideas on how best to dislodge the log and free the cables. This really showcased one of the (many) challenges of science in the benthic zone. Even with multiple high-resolution video streams to survey the situation, the options to dislodge the log were limited to what could be achieved using only Jason’s two manipulator arms. At 2400, I handed off my shift mid-dive and headed down to get some sleep. Overall a great first full day aboard!