NOAA Teacher at Sea
Aboard R/V Sikuliaq
June 29 – July 18, 2019
Mission: Northern Gulf of Alaska (NGA) Long-Term Ecological Research (LTER)
Geographic Area of Cruise: Northern Gulf of Alaska
Date: July 11, 2019
Weather Data from the Bridge
Latitude: 59° 00.823 N
Longitude: 148° 40.079 W
Wave Height: 1 ft, ground swell 3-4 ft
Wind Speed: 5.4 knots
Wind Direction: 241 degrees
Visibility: 5 nm
Air Temperature: 13.3 °C
Barometric Pressure: 1014.6 mb
Science and Technology Log
At home, I regularly check information from the buoys that literally surround our islands. They give me real time, relevant data on ocean conditions and weather so that I am informed about storm or surf events. We also have buoys that track tsunami data, and the accuracy and timeliness of their data can save lives. Deploying and monitoring these buoys is a job that requires knowledge of ocean conditions, electronics, rigging and computer programming.
Pete Shipton is onboard as the mooring technician from UAF’s Seward Marine Center. This morning, he, Dr. Danielson and the crew deployed three moorings near oceanographic station GAK6i (about 60 miles offshore in the Northern Gulf of Alaska) at a depth of 230 meters. The search for the right depth required that R/V Sikuliaq do an acoustic survey of the area last night to find a kilometer-long area of the right depth and bottom slope. The three moorings will be situated close enough to each other that for all purposes they are collecting a co-located set of readings representative of this site, yet far enough apart, with small watch circles, that they don’t overlap and foul each other. The set of three is designed to have one surface buoy on either side with sensors at the surface and through the water column and a third buoy in the middle with sensors also distributed across all depths.
The first buoy, GEO-1, gives information on physics, optics, nutrient
chemistry and has a profiling instrument that will “walk” up and down the mooring wire from about 25 m above the seafloor to 25 m below the surface, collecting profiles four times a day. The mooring has many of the sensors that the ship’s CTD has, including an ADCP (Acoustic Doppler Current Profiler), a weather station with a GPS that measures wind speed, relative humidity, sea level pressure, and air temperature. The buoy system was designed to withstand and operate in 8 m waves; in larger waves the surface buoy is expected to become submerged. At one meter of depth, GEO-1 measures the temperature, salinity, chlorophyll fluorescence and photosynthetically available radiation.
On GEO-2 (the center buoy), similar data is recorded at 22 m below the surface. There will also be a sediment trap, mammal acoustics recorder, particle camera, and an AZFP (acoustic zooplankton fish profiler), which has four frequencies that can detect sea life from the size of fish down to the size of zooplankton. It records sound reflections from all sizes of creatures and can see fish migrations during day or night within a range of 100m (from 100m depth to the surface).
Buoy GEO-3 is the primary “guard” buoy, or marker for the whole set. It also has a real-time transmitting weather station and near-surface measurements.
Linking the mooring lines and the anchors are acoustic releases,
which are remotely controlled tethers whole sole function to listen for a “release” command that will tell them to let go of the anchor. Since the limiting factor on the instruments is the life of the batteries, they will be picked up in a year and the acoustic release will allow the instruments to be brought back aboard Sikuliaq. These buoys will be providing real time information for groups such as the Alaska Ocean Observing System (www.aoos.org) about weather and ocean conditions, while also collecting
information about sea life in the area.
Deploying the buoys was a lengthy process that required careful
coordination of parts, lines, chains and personnel. Luckily everything
went off perfectly! As the anchor weights for the two surface buoys deployed, they briefly pulled the buoys under, causing a bit of joking about whether the line length was calculated correctly. The brief “dunk test” was an excellent first trial for submergence during this coming winter’s storm conditions.
There are opportunities for careers at sea in a wide variety of positions on board a research vessel. One of the most interesting is the MarTech (Marine Technician), because of their dual role during a scientific cruise.
The Marine Technicians are technically assigned to the science team although they are a part of the ship’s crew. Bern and Ethan are the MarTechs on this cruise and both work specifically with R/V Sikuliaq. They are considered a part of whatever science team is on board at the time. The MarTechs are on 12-hour shifts, from 8:00 to 8:00. Ethan is on at night, and Bern is on during the day, although there is some overlap. The two men help to deploy and recover instruments for the science team and as well as helping the crew with any deck operations. They also are responsible for the computer lab and overseeing the data displays and production from the various sensors, as well as maintaining the instruments on the ship that provide information. Although they are always at hand to help when we need it, you will often find them also repairing and upgrading ship’s equipment and helping with engineering tasks.
Bern has been a MarTech on R/V Sikuliaq since 2013, and had previous experience on other research vessels, both American and international. Bern is also the ship’s unofficial documentation guy; he has a number of small cameras that he regularly uses to capture the action on board, whether from the vantage point of one of the cranes or on top of his own helmet. You can find examples of Bern’s camera work on R/V Sikuliaq’s Instagram site (@rvsikuliaq).
Like Bern, Ethan has also worked on other research vessels but has been on R/V Sikuliaq since it was built. This is the only ship he’s been a MarTech on. His interest in oceanography, especially marine acoustics, led him to this career. Marine acoustics is more than just listening for large species such as whales. There are acoustic sensors that “listen” to the ship and help ensure that it is functioning normally. Other acoustic sensors, such as the ones based in the open keel of the ship use sound technology to map the ocean floor as we progress on our path. Ethan was kind enough to show me the keel and explain the instrumentation. In addition, there are instruments that constantly record salinity, temperature, current strength, solar radiation and other measurements along the path we travel to provide a more complete picture of the environmental conditions existing at every point.
The marine technicians manage the computer lab when they are not needed for operations. This lab is the nerve center of the ship and allows the science team to work closely with the bridge to coordinate the movement of instruments and the speed of the vessel through the water to achieve optimum results. You can find information on meteorology, navigation, engine performance, depth sounders, closed circuit monitors, ship acoustics and deck winch statistics by looking at specific screens. In addition, the staterooms have monitors that also allow viewing of certain screens.
By far the two displays that are followed most closely are the CTD cast screens and the AIS screen. The AIS screen gives our course on a map, and shows our progress as well as future waypoints. It also shows our speed and bearing to our next point as well as ocean depth and wind speed and direction. The CTD screen shows real-time results in a number of categories such as salinity, oxygen, chlorophyll, temperature, nitrates and light as the CTD descends and ascends through the water column. Based on the results of the down cast, the teams determine the depths from which they’d like water samples collected as the CTD rises.
The equipment on the bridge represents the pinnacle of technology as far as ship operations go. The captain’s chair has been described by some members of the science team as the “Battlestar Galactica” or “Star Trek” chair, and it really does look like it fits in a science fiction movie. Displays on the bridge show performance of the engines, radar returns and our bearing and range from them, and any other pertinent information to vessel performance. Ship movement and waypoints are hand plotted by the second mate, who also oversees ship movement along with the captain, chief mate and third mate. The ship’s officers work the bridge on a rotating watch schedule. One of the cool features of this ship is that it operates two Z-drives, similar to what is used on tugboats. These are propellers that can move independently of each other and turn in any direction. They allow the ship to be maneuvered precisely, which is a great help when we need to stay on a station through multiple operations. Various views of the bridge and the navigational instruments used by the ship’s crew are shown in the gallery below.
Happy Mooring Day! It’s our self-declared “national holiday”! Because the process of deploying the moorings and buoys took up all of the morning and a part of the afternoon, most of the rest of the science team took the morning off and slept in. So many of them ran on the treadmill that running might become a part of our “holiday” tradition. My roommate even took bacon back to her room to eat in bed. Gwenn brought out her Twizzlers…somewhat appropriate because they look like steel cable (even though the moorings did not use cable). It was a nice breather for the science team, who have been working very hard to collect samples and run experiments. Somewhere along the line, the idea of making Mooring Day a “holiday” caught on, and it’s become a bit of a joke amongst the team. We’re down to a week to go, and everyone is beginning to think about what happens when we get in and when we all go home. But… we’re not quite there yet, and there’s a lot of work left to do.
Animals Seen Today
We apparently have a stowaway…a small finch-like bird that flits about the ship. It must have joined us when we were near land, and now we ARE the land.