The crew of the R/V Weatherbird II deploys CTD sampling equipment at the Bermuda Atlantic
Time-series Study site |
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At least once a month, BBSR's
research ship sets sail for the
Bermuda Atlantic Time-series Study (BATS) site 50 nautical miles southeast of Bermuda. These cruises provide essential insight into how the
ocean works and how it affects global climate change. Scientists and crew work around the clock to collect and analyze data and samples, both for BBSR's ongoing studies and for
scientists around the world. BATS cruises generally take place in two "legs," with a night at dock after the first leg to allow an exchange of scientists and equipment.
We asked Vivienne Lochhead, a BATS research technician and the chief scientist on this trip, for a behind-the-scenes look at a typical day on board the Weatherbird II…
although a day in the life of the Weatherbird stretches well beyond 24 hours. Friday
3:00 pm: We load our equipment onto the ship. It takes two trips in the
truck to move everything we need from the BATS lab and the nearby marine warehouse. We make sure everything is tied down correctly – there's nothing worse on a rough cruise than getting hit in the head by a
large wooden filter rack! Monday
8:00 am: We run through the checklist and everything is set. One last glance at the weather forecast. We could have a couple of rough days
ahead, but nothing bad enough to stop science. I have a quick chat with the captain to make sure he's ready to go. The scientists prepare by swallowing their various seasickness concoctions.9:00 am:
We are off to the high seas in the name of science. The winds are 10-15 knots and the seas are 4-6 feet. We convene in the galley for the
safety meeting. The galley is not only the kitchen, but also our dining, living and entertainment area. As we head out to the deep ocean, we have a fire
drill and an abandon ship drill. Newcomers try on the awkward survival suits (dubbed "Gumby" suits). 11:30 am: We arrive at Hydrostation "S," 15 nautical miles southeast of
Bermuda, just in time for lunch. Unfortunately, Brian Fredin has to abandon his to start sampling the optical quality of the water. Brian is a research technician for the Bermuda Bio-optics Project (BBOP), a NASA-funded
program that determines the level of biogeochemical productivity in the ocean by looking at its color on satellite images. Brian launches a torpedo-like instrument called the Spectral Profiling Multi-channel
Radiometer (SPMR) down to 150 meters and repeats this five times as the NASA SeaWiFS satellite passes overhead. These casts provide the "ground truth" for the satellite's observations. 12:30 pm:
Brian gets back to his food. I help launch the CTD equipment. CTD stands for conductivity, temperature and depth, and gives us a profile
of the water's temperature and salinity. It's also equipped with oxygen sensors and fluorometers, which measure fluorescence in the water
column. I go up to the bridge to check the profile of the water column that is being transmitted to the computer. At Hydrostation, we sample down to
2,600 meters, firing (or closing) the 24 bottles at various depths. We analyze for oxygen, salts and dissolved inorganic carbon. 4:00 pm: The CTD is brought safely back on board and sampling by the
BATS research technicians begins. Debra Clougherty decides to sample the deep bottles (brave girl – the water can be numbingly cold!), Megan Roadman samples the shallow ones, Paul Lethaby measures the
temperature of the water in the bottles, and I fix oxygen samples with chemicals. We also take samples for Dr. Charles Keeling at Scripps
Institution of Oceanography, and salt samples for BATS. The ship heads towards the PITS (Particle Interceptor Trap System) deployment site. We eat dinner on the way. 8:00 pm:
We arrive at the PITS site. PITS is deployed with a 90lb weight attached to the bottom of 320 meters of line, with traps and a current meter
at intervals along it. There are also surface buoys with a spar that holds a satellite transmitter, strobe light and a radio directional finder (RDF). 9:00 pm:
We head back to the BATS site. I e-mail Rod Johnson, the BATS lab manager, to let him know we've had a successful deployment so he can start tracking the satellite hits and relay the PITS location.
9:30 pm: We arrive at BATS and prepare a pump cast for BBSR's Oceanic Microbial Observatory
with Dr. Craig Carlson (University of California Santa Barbara) and Dr. Steven Giovannoni (Oregon State University).10:00 pm:
Debra and Paul go into the galley to select a video from our limited collection. I fill out the cast sheet for the next morning's production
and make sure everything is ready, then retire to my bunk for some precious sleep. 11:30 pm: Debra and Paul retrieve the pump cast, then go off to bed. Tuesday
R/V Weatherbird crew and scientists retrieve a plankton net tow |
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12:01 am: Megan is up for the plankton net tows. First is the phytoplankton tow. The net is
deployed straight down to 150 meters and straight up again.12:20 am: Megan retrieves the cod end (the collection receptacle of the net). She places her sample into a
jar, then starts on two zooplankton tows down to 200 meters. 1:15 am: The net reaches the surface. Megan takes the cod end into the lab. Before she processes that sample, she places a second
cod end on the net so it can be deployed again. She divides her first sample of zooplankton, which contains some really cool things, like lobster larvae, eel larvae and fish
eggs, into two random samples using a plankton splitter. The second net tow reaches the surface and Megan repeats the process. 3:30 am: Megan retires to her bunk for some much needed rest. The ship
departs the BATS station to check on PITS and record its new location. 4:30 am: I receive my wake-up call (Ugh! Way too early!) as the boat
repositions itself on BATS. I go to the bridge to give the weather fax a quick glance. We may have 20-knot winds today with 5-7 foot seas. Not ideal, but we can still work in it. 4:45 am:
Paul, Brian and I do a "Go-Flo" cast with Kevlar wire to avoid trace-metal contamination. Debra wakes up to help us with the sample collection.
Chief scientist Vivienne Lochhead (right) and research technician Megan Roadman prepare
flasks for BATS sampling in the radioactive van, a movable laboratory on the back deck of the Weatherbird II |
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5:15 am: As the Go-Flo bottles are being brought onto deck, I retrieve the first set of samples and retreat into the radioactive van, a moveable lab
located on the back deck – my cave. Debra brings the rest of the samples to me as they come up. I spike them with radioactive carbon so we can determine the uptake of carbon by
phytoplankton. The flasks containing the samples will be deployed at various depths to 140 meters before sunrise and will drift around until sunset. Debra takes samples to spike
with tritiated thymidine to measure for bacterial production. Brian and Paul take samples for chlorophyll and salinity measurements. The flasks are
deployed with a satellite transmitter, RDF unit and strobe light.6:15 am: Everyone heads into the galley for breakfast. I send an update e-mail to Rod while some of the scientists catch a quick nap.
8:00 am: Brian starts the first of many Spectral Profiling Multi-channel Radiometer (SPMR) casts. I prepare the lab for the shallow core cast. 10:00 am:
The CTD is launched for a calibration cast and the shallow core cast. 11:30 am: The CTD is on the deck and we go to work. Samples include
dissolved oxygen, dissolved inorganic carbon (for Dr. Keeling and for BBSR's Dr. Nick Bates), dissolved organic carbon/nitrogen, nutrients, salts, sugars (Dr. Craig Carlson), urea (Dr. Mike Lomas at BBSR),
particulate organic carbon/nitrogen, particulate silicate, pigments, bacteria, viruses, bacterial probes, flow cytometry, and whole phytoplankton studies. 1:00 pm:
Debra, Paul and I filter water for particulate and pigment samples. Megan gets her lab space ready for daytime zooplankton net tows. 3:00 pm: We prepare to launch the CTD for the optics cast.
5:00 pm: The CTD is on deck and we start sampling for chlorophyll a, particulate absorption, colored dissolved organic matter and more thymidines for bacterial production. 6:00 pm:
All the scientists, except Brian, who is still doing SPMR casts, go into the galley to see what's for dinner. 6:30 pm: Brian gets to eat! 7:30 pm:
We relocate the flasks and retrieve them. Megan and I head into my cave to process them. 9:00 pm: Brian starts yet another SPMR cast (dark profile). I take a quick catnap. 11:00 pm:
I wake up for the deep core cast. We launch the CTD to 4,200 meters then go up to the bridge to watch the profile. I bring a book since this cast will take over four hours. Wednesday
3:00 am:
I wake the other scientists to many grumbles and groans! The CTD is back on deck and we begin sampling as the ship moves northwest towards Spatial Station #1, 30 miles away.5:00 am:
We finish sampling just in time for breakfast. I go for a short nap. 7:00 am: My wakeup call comes and we launch the CTD for a profile down to 1,200 meters. 8:00 am:
The CTD is recovered, and I crawl back into my bunk as we depart for Spatial Station #3, 30 miles northeast of BATS. 12:30 pm: We arrive, but the winds are 25-30 knots with stronger gusts,
and the seas are 8-10 feet. We won't be able to do the CTD cast or the noon SPMR cast. We head back to BBSR. 5:00 pm: We arrive at the dock, unload some equipment and lose a few
scientists. Brian and I will be back before 8:00 am tomorrow for the second leg, a two-day cruise that includes recovery of PITS, and more SPMR profiles and CTD casts. Can't wait until Friday night! |
