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Environmental Monitoring


August 2011 Issue

Researchers Obtain More Tools to Monitor the Mediterranean
Researchers in the Balearic Islands and beyond will soon have more tools to understand the environmental conditions in the western Mediterranean Sea through a recent contract award to SIDMAR, which represents AXYS Technologies Inc. (Sidney, Canada) in Spain.

AXYS announced in June a contract award to supply a variety of monitoring equipment, including buoys, ROV and gliders, as well as service and maintenance. AXYS will supply two 1.8-meter WatchMate data buoys, which will be delivered this fall. These new monitoring platforms will be deployed in 40 and 800 meters of water and will capture a wide variety of data parameters, including winds, barometric pressure, temperature, waves, currents, conductivity, temperature and dissolved oxygen.

Subsurface sensors will be deployed along a mooring line and will transmit data via an acoustic modem up to the WatchMate buoy. The buoys will transmit all collected data each hour via two types of telemetry: GSM for the nearshore buoy and Iridium Communications Inc. (Bethesda, Maryland) satellite for the offshore buoy. The buoys will be outfitted with secondary telemetry devices, and all data will be logged for time series and historical studies.

Data will be received and displayed by researchers at Sistema d'observació i predicció costaner de les Illes Balears, a coastal ocean and observing and forecasting system located in the Balearic Islands. For more information, visit www.sidmar.es.

EMU Ltd. Detects Tsunami in the English Channel
A network of coastal tidal and wave monitoring stations maintained by Southampton, England-based EMU Ltd. recorded the progress of the waves caused by a minor tsunami.

In late June, a massive underwater landslide in the Atlantic 200 miles off the Cornish coast is believed to have caused a small tsunami along the south coast, which created waves of between 0.5 and 0.8 meters and resulted in abnormal tidal records at the Channel Coastal Observatory and Plymouth Coastal Observatory shore stations.

Robin Newman, EMU's principal metocean scientist, initially thought there was a malfunction with the oceanographic instruments, which were installed by EMU for the Southeast and Southwest Regional Coastal Monitoring Programmes, due to the unusual data patterns recorded.

"There was a significant amount of variation in the observed data against what would be expected, so I checked at multiple sites and they were all consistent with some sort of movement from east to west," Newman said. "We subsequently realized we had recorded what appears to be a minor tsunami."

Newman said the tsunami, while a rare event for the area, could have caused flooding had it arrived with the high tide. For more information, visit www.emulimited.com.

NASA Plans Vast Ocean Study to Ground Truth Aquarius Data
When NASA's Aquarius mission launches, its radiometer instruments will take a reading of the oceans' salt content in the top centimeter of the ocean surface, creating weekly and monthly maps of surface salinity over the globe for at least three years.

To better understand the cause and impacts of changes in salinity, scientists will deploy instruments on floats, research ships, commercial cargo ships, free-drifting platforms, buoys, underwater gliders and an AUV to build a 3D view of what is happening beneath the ocean surface.

"The next question is: How do you understand what the satellite sees?" said Aquarius project scientist Yi Chao, of NASA's Jet Propulsion Laboratory. "Without deploying instruments under the ocean's surface, we do not know how to fully interpret the satellite observations of surface salinity."

To address that question, NASA has a new field experiment, Salinity Processes in the Upper Ocean Regional Study (SPURS). The experiment, which will sample salinity and other key factors such as ocean temperature and velocity, will take place from spring 2012 to summer 2013 and will include five month-long research ship cruises to the center of the Atlantic surface salinity maximum.

Many of the methods used for years to take in-ocean measurements of salinity will be put to use, but in a far more concentrated and intensive manner, and, for the first time, they'll be used in combination with Aquarius' satellite salinity readings.

SPURS scientists hope to replicate the study in a contrasting, relatively low-salinity region elsewhere in the ocean in the future.

The scope of the measurements taken during SPURS will give scientists deeper insights into the salinity observations from Aquarius and the physical processes—temperature changes, currents, turbulence, evaporation and precipitation—that affect salinity. For more information, visit www.nasa.gov.

Record Dead Zone Predicted in Gulf Due to Mississippi Flooding
Extreme flooding of the Mississippi River this spring is expected to result in the largest Gulf of Mexico dead zone on record, according to a University of Michigan aquatic ecologist and his colleagues.

The 2011 forecast, released June 15 by NOAA, calls for a gulf dead zone of between 8,500 and 9,421 square miles, an area roughly the size of New Hampshire. The most likely 2011 scenario, according to University of Michigan scientist Donald Scavia, is a dead zone of at least 8,500 square miles, surpassing the current record of 8,400 square miles set in 2002. The average over the past five years is about 6,000 square miles.

This year, stream-flow rates in the Mississippi and Atchafalaya rivers were nearly double of what is normal in May, significantly increasing the amount of nitrogen and phosphorus transported by the rivers into the gulf.

The U.S. Geological Survey estimates that 164,000 metric tons of nitrogen were transported this May to the northern Gulf of Mexico off the Louisiana coast. The amount of nitrogen transported to the gulf this May was 35 percent higher than average May nitrogen loads estimated in the last 32 years. For more information, visit http://ur.umich.edu.


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