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Environmental Monitoring


November 2013 Issue

Sensors, Glider Monitor US West Coast Waters
In early August off the U.S. East Coast, a team from Sonardyne International Ltd. (Yateley, England), Liquid Robotics Inc. (Sunnyvale, California) and NOAA concluded the second leg of an extensive ocean observation technology demonstration project. Using Sonardyne’s Fetch and Tsunami sensor nodes and a Liquid Robotics Wave Glider, the project was performed in collaboration with MARACOOS (Mid-Atlantic Regional Association Coastal Ocean Observing System) and NOAA’s National Data Buoy Center (NDBC) and managed by NOAA’s U.S. Integrated Ocean Observing System (IOOS) Program Office with the objective of testing new long-endurance ocean observation instruments that have been designed to work in tandem.

The Fetch node was deployed in 550 feet of water to measure ocean temperature and pressure, and the Tsunami sensor in 8,000 feet, while the Wave Glider recorded data on the wind, waves, water temperature and salinity as it transited between the two sensors. Once the Wave Glider was stationed above the location of each instrument, it acoustically uploaded both real-time and logged data, which were then transmitted via satellite to shore-based operators for analysis.

Sonardyne’s Fetch and Tsunami sensors are long-life subsea sensor logging nodes that enable data to be extracted on demand from platforms such as Wave Glider via their integrated high-speed acoustic modems. Fetch can be configured with an array of different sensors dependent on the monitoring application with standard sensors, including high-accuracy pressure, temperature and sound velocity. The Wave Glider is an autonomous ocean observing platform designed to support a wide variety of sensor payloads. Capable of travelling long distances and monitoring vast areas without refueling, Wave Gliders can transmit data via radio satellite without ever requiring a ship to leave port, thereby reducing risk and survey costs. The data will help improve understanding and prediction of what is happening in the ocean and could improve the ability to predict and detect incoming tsunamis. For example, the tsunami sensor captured the small seismic event that occurred off the East Coast on June 13. The technology enabled uploading of the data and transmission to investigating scientists.

Warming of Greenland Deep Sea 10 Times Higher Than Global Rate
Recent warming of the Greenland Sea deep water is about 10 times higher than warming rates estimated for the global ocean, according to scientists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) who published their findings in Geophysical Research Letters. They analyzed temperature data from 1950 to 2010 in the abyssal Greenland Sea, south of the Arctic Ocean.

The cause of the warming is a change in the subtle interplay of two processes in the Greenland Sea: the cooling by deep convection of very cold surface waters in winter and the warming by the import of relatively warm deep waters from the interior Arctic Ocean.

Since 1993, AWI oceanographers have carried out regular expeditions to the Greenland Sea on board the Polarstern to investigate the changes in this region, including extensive temperature and salinity measurements. They have combined this long-term data set with historical observations since 1950. They found that in the last 30 years, the water temperature between 2,000 meters depth and the seafloor has risen by 0.3° C.

The amount of heat accumulated within the lowest 1.5 kilometers in the abyssal Greenland Sea would warm the atmosphere above Europe by 4° C.

The AWI scientists will return to the Arctic in 2015 to continue their study, which has implications for understanding how climate change affects the oceans.

First-Time Monitoring of Irish Winter Seabed Ploughing
A project that has allowed the Port of Cork to precisely monitor and record the winter program of seabed ploughing in real time for the first time ever is being delivered by Succorfish (North Shields, England) in partnership with SEA-Tech Evolution Ltd. (Ringaskiddy, Ireland).

Succorfish has installed its SC2 vessel monitoring unit and RFID winch sensors aboard MV Denis Murphy, a 20-meter multicat utility vessel used for maintenance duties such as bed leveling and oil pollution response.

Over the next six months, Port of Cork and SEA-Tech personnel will have the ability to accurately record vessel movement more frequently and in real time, and analyze activity as it happens from specific harbor areas using the system’s geofence facility.

Emissions Monitoring System for Largest FSRU
Martek Marine (Rotherham, England) has delivered an emissions monitoring system to Daewoo Shipbuilding & Marine Engineering Co. Ltd. (Seoul, South Korea) for the world’s largest floating storage and regasification unit (FSRU). The 173,400-cubic-meter vessel, which can also function as an LNG carrier, is due for delivery in May 2014 when it will be deployed in Brazil.

The equipment monitors nitrogen oxide, sulphur oxide, carbon dioxide, carbon and methane; total hydrocarbons; nonmethane hydrocarbons; benzene; nitrous oxide and particulates. It is unique for a system to measure so many different emissions, and benzene and nitrous oxide are only monitored very rarely, Martek said.

Martek expects to build more complex monitoring systems as the European Union pushes for emissions monitoring legislation for the maritime industry.

Another factor will be Emissions Control Areas (ECAs) coming into force and, later, tightening their requirements. The first ECA, which is in North America and covers ships trading off the coasts of Canada and the United States, came into effect August 2012 and enforces stricter controls on sulphur oxide, nitrogen oxide and particulate matter emissions. North America is the third functioning ECA; the others restrict only sulphur dioxide, and they are in the Baltic Sea and the North Sea. A fourth ECA is due to come into force in the Caribbean Sea on January 1, 2014.


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