Monterey Bay Aquarium Research Institute
Pelagic-Benthic Coupling
Iceberg Research

ROV on Deck
The ROV sits on deck waiting to deployed.
One of the key factors in determining the impact the icebergs have on the surrounding environment is to get an idea of what goes on beneath the water line. Given the unpredictable and dangerous nature of icebergs the research vessel must keep a safe distance away. This obviously makes it difficult to glean anything from under the water line. To address this issue we use a Remotely Operated Vehicle or a ROV. The ROV is connected to the vessel through an umbilical tether. This tether allows the ROV to both receive power as well as send information back to the ship such as video or data from a variety of sensors. The ROV also has a manipulator arm that allows it to collect a variety of samples for analysis back on the ship.

Underside of iceberg
The underside of an iceberg is marked with this dimpling pattern.

Due to the size of most icebergs it is not possible to study the underside using the ROV. In order to collect samples then we needing something else. The engineering group at MBARI developed a free floating device that would float at a depth below the icebergs and collect any particulate matter falling from it as it goes overhead called a Lagrangian Sediment Trap. The trap is deployed from the ship and will sink doing to set depth. Once it reached that depth a pressure switch will release ballast and the trap will become neutrally buoyant at the selected depth. It will then open it's collection cups while the iceberg floats overhead. Any particulate matter that sinks down will be collected by funnels leading down to the cup. Once the trap is ready to come to the surface the cups will close and it will activate it's adjustable buoyancy system and begin it's rise to the surface. The trap is then recovered onto the ship once it is back on the surface.

UAV with GPS beacon affixed to bottom
The UAV with GPS Beacon attached.
UAV being deployed
The UAV flies towards an iceberg.

In addition to know what effects free drifting icebergs have we need to know how long these bergs are affecting the environment. Some larger icebergs can be tracked using satellite imagery but some of are study bergs were too small for this. So we needed a new approach to keeping tabs on icebergs. To do this we decided to stick a custom made GPS tracking device on top of the icebergs. Given costs and cargo constraints aboard the vessels we used an Unmanned Aerial Vehicle or UAV. Our UAV was a model remote controlled airplane that we modified with a camera and a mechanism to drop our tags on the top of the icebergs. After the tags have been dropped they report on their position at set intervals using satellites.

Many animals live around the icebergs and to get an understanding of what those animals are and in what abundances they are we needed to be able to collect large numbers of them. The device of choice for this was the Multiple Opening Closing Net Environmental Sensing System or MOCNESS. The MOCNESS is a large square frame that has several nets attached to it and is towed behind the ship by a cable wire. Through the wire a controller on the ship is able to open and close the nets to selectively sample specific regions of interest around the iceberg. Once the nets are back aboard the ship scientists go through the catch and assess what was caught. Animals are sorted by species and then various measurements are taken to give an idea of what types of animals as well as their abundances are near the icebergs.

MOCNESS being deployed
The MOCNESS is deployed off the back of the vessel.
Controlling the MOCNESS
Dr. Ron Kaufmann controls the MOCNESS from one of the labs aboard the ship.
Last updated: Feb. 05, 2009