RVIB Nathaniel B. Palmer, ROV Phantom, Unmanned aerial vehicle, CTD, Felume, GPS Drop Tags, Lagrangian sediment traps, MOCNESS trawls, Tow fish
RVIB Nathaniel B. Palmer
The Research Vessel Ice Breaker (RVIB) Nathaniel B. Palmer is a specialized
ship for science operations that is more than 308 feet long and capable of
breaking three feet of ice at three knots. The ship houses up to 68 people
onboard, including the crew, science teams, and research staff. More
information about the RVIB Nathaniel B. Palmer can be found at the USAP
The IceCUBE (Ice Cold Unit for Biological Exploration) is a modified Phantom S2 remotely operated vehicle (ROV) specifically outfitted for the research goals of the scientists. It is tethered to the ship by a cable, and relays physical parameters of the water (conductivity, temperature, depth, turbidity), video footage, and other instrument data in real-time, and can continuously pump water back to the ship. In addition, the ROV will collect plankton near the iceberg using a suction sampler, plankton nets, and an ice scraper.
Lagrangian sediment traps
Sediment traps are used to collect sinking organic matter as it descends
toward the seafloor. From the organic matter, the science team will be
able to measure how much carbon is being exported from the iceberg, what
makes up the sinking matter, and what trace elements are found in it. Most
sediment traps are moored in one location to collect sinking matter.
Lagrangian sediment traps drift with the currents, following similar paths
as the drifting icebergs.
The unmanned aerial vehicles (UAVs) are remote-controlled airplanes used to
deploy GPS drop tags onto the iceberg to track movement over time. Strong
winds and cold temperatures make flying these airplanes very
difficult—the pilots trained for many months prior to the cruise. The
planes must take off from the helicopter pad on top of the ship and then
return and land safely back on the helicopter pad.
GPS drop tags
To track iceberg movement over time, GPS tags are dropped onto the surface
of the icebergs. These drop tags consist of a GPS unit, a modified Nerf
football for a cushioned housing, stabilizers that keep it from sliding off
the iceberg, batteries, and an antenna for transmitting their locations
back to the ship. These tags are dropped by the UAVs (unmanned aerial
The Tow Fish is an instrument that is deployed from a boom while the ship
moves slowly ahead. The tow fish pumps large volumes of water up to the
ship for trace element and isotope analysis, and can be towed in shallow or
deep (to 300 m) water. Iron and its tracers change forms quickly in
seawater, which necessitates near-instantaneous sampling of fresh seawater,
before the iron transitions to one of its other states.
This instrument measures concentrations of iron (Fe II), a trace metal that
originates from land and is often limited in the ocean. Icebergs, which
originate from land, transport iron far out into the ocean before they
melt. The FeLume, or Flow Injection Chemiluminescence, system can measure
low concentrations of iron (II) in seawater near and far away from the
A MOCNESS trawl is an advanced trawling net that allows researchers to
collect plankton samples at various depths and water conditions. MOCNESS
stands for “Multiple Opening and Closing Net, with an Environmental
Sensing System.” Unlike a simple Tucker trawl, which uses one net, the
MOCNESS has multiple nets that are remotely opened and closed by the
scientists. This is useful for collecting samples at different depths. In
addition, the “Environmental Sensing System” monitors the water
conditions around the trawl real-time, so scientists can sample specific
regions such as those of lower temperature or salinity.
A CTD is a series of sensors that continuously measure conductivity
(salinity), temperature, and depth. It is normally housed in a large
rosette of Niskin bottles that are lowered over the side of a ship on a
wire cable. Niskin bottles are open at the beginning of a CTD deployment,
but during ascent they are remotely triggered to close at different
intervals, collecting water samples at discrete depths.