The Rutgers Coastal Ocean Observatory Lab (COOL) employs several Slocum Electric Gliders, capable of travel for 15 to 30 days. These autonomous vehicles travel to depths up to 200 meters, moving in a sawtooth fashion. Taking advantage of buoyancy, it moves up and down to record both the vertical and horizontal water columns and navigates with the aid of GPS. The image to the right shows several days worth of glider data as it moved through a Gulf Stream filament impinging on the coast during our cruise.

ABSTRACTThe RIOS group project started with a May 27, 2005 research cruise aboard the R/V Sorenson Miller. The cruise left Staten Island, occupied a station near the Battery, and then conducted a transect off Shrewsbury Rocks. The cruise was informed with data collected by the Rutgers University Integrated Ocean Observing System. We collected hydrographic data using a CTD, acoustic data with a scientific echosounder, and water samples for chemical analysis. We found that the coastal ocean was considerably fresher than it was in May of 2004. This difference is likely due to significant flooding and fresh water discharge experienced in the area earlier in the year.

INTRODUCTION/METHODSBeginning in the COOL room, we examined the most recent observatory data and discussed how oceanography had advanced toward real time acquisition multi-sensor data over large areas of the ocean. These data helped design the cruise track for the day and provided a priori information about the state of the coastal ocean. RIOS then boarded the R/V Sorenson Miller a sailed from State Island, NY on the morning of May 27, 2005. We occupied a station near the Battery in New York Harbor and then sailed out onto the NJ shelf to conduct a cruise across the Hudson River plume starting at Shrewsbury Rocks and heading due east. Continuous hydroacoustic records were obtained. CTD and water samples were obtained approximately every 1 km along the transect. Data were processed shipboard as well as back ashore during periodic data workshops.

The cruise and data analysis served to highlight the evolving role of IOOS technology in oceanography and the dynamic nature of the coastal ocean.

Using the L-Band and X-band satellite dishes located on the roof of the Institute of Marine and Coastal Sciences, images depicting sea surface temperature and chlorophyll concentration can be produced. Data is compiled and processed in the COOL room of Rutgers University, allowing for analysis of the aforementioned information.

On the day of our cruise, satellite imagery indicates that the areas we transected had an average surface temperature of approximately 13°C (55°F). Though similar surface temperatures can generally be seen in waters proximate to the shore, temperatures followed a decreasing gradient farther out from the shore until meeting warmer waters of the Gulf Stream. Yet, not only are these data useful in examining sea surface temperatures, but they can also be indicative of temperatures at greater depths in the absence of an unexpected thermocline.

Due to the fact that the data were collected early in the season, we observed low chlorophyll productivity. Some spots of local upwelling can be observed along the southern New Jersey Coast. However, in the areas which we transected, such upwelling was minimal. Furthermore, though some points of high activity were in fact seen in both the Hudson River and its mouth, little was seen in our oceanic transect.

CODAR, or Coastal Ocean Dynamics Applications Radar, can be used to assess ocean surface currents in a way that can be applied to complete ocean mapping. The Rutgers University CODAR System, which consists of sites located at Brant Beach, Brigantine, and Tuckerton, is in fact the only HF-Radar system operating in the eastern United States. CODAR works by sending a signal out to the ocean and then measuring the intensity of the signal reflected back by the waves.

In these examples, one can see how the surface ocean currents can fluctuate within a short period of time. For instance, at 10:00 GMT, the currents diverge northeast and southeast such that one might suspect that there is an upwelling within the middle of this divergence zone. Furthermore, the vectors depicted on this field represent an ebb tide. However, at 12:30 GMT, the vectors portray a flood tide.

A SIMRAD EY60 hydroacoustic unit with a 120 kHz transducer was used to help visualize the structure of the water column below our vessel. Horizontal layers are often observed. These data can then be compared with CTD data to determine if hydrographic structure corresponds to the layers seen in the acoustic image. The figure to the right shows an hour of acoustic data collected along the transect. The insets show approximately 1 minute of data. Note the layering in the first in both inset and the mixing and frontal features in the second.

THE RIOS EXPERIENCE In 2005, fourteen students from across the country participated in the IMCS/NSF sponsored REU Site RIOS - Research Internships in Ocean Sciences. This program provided an opportunity to design an independent research project with the guidance of researchers at a renowned research institution. For many of us, the program offered an opportunity to explore a new area and experience a research environment firsthand. We were exposed to a wealth of information ranging from the dynamics of the coastal ocean, to our individual research, to working through a research program overall. Working with other students with the same experience but from different backgrounds, we looked to each other for advice and a sense camaraderie.

The program began with a week of group activities and a research cruise to the Hudson River plume. Over the next ten weeks, each student worked on an independent research project with a faculty mentor either IMCS in New Brunswick or RUMFS in Tuckerton. Occasionally we gathered for research talks or demonstrations and to analyze the data from the Ocean Observatory and the research cruise.RIOS culminated in a formal poster session at the end of the program.

Surface Data Subsurface Data

RESULTSCONCLUSIONS AND DISCUSSION

One of the great limitations oceanographers have been forced to work under is the time it takes to collect data relative to the time it takes for the system under study to change. This limitation is especially troublesome in a system as dynamic as the New York Bight, where tides, river discharge, and winds are constantly pushing and pulling at the ocean.

Our experience has shown how sampling technologies can been used to bridge this gap, allowing us to take a snapshot of the ocean from several perspectives. These snapshots provide us with the unparalleled opportunity to "see" the processes driving the coastal environment while they occur. This knowledge is extremely useful in many contexts, from understanding how larval organisms, pollution, or sediments are transported, to more mundane things, like whether or not today is a good day for swimming at the shore.

As a tool, IOOS has the potential to change the way many oceanographers work. Having good information on the state of the coastal environment at the time you are on it, allows researchers to target their sampling efforts. Transect and positional sampling methodologies have proven to provide excellent data in stable systems, but the high amounts of variability characteristic of the New York Bight require large amounts of data to overcome. By targeting sampling effort in oceanic regions identified with the IOOS, a great deal of this variability can be controlled for. Not only are these data better for being less variable, but they also could save a great deal of money in ship time, materials and manpower.

RIOS 2005: Undergraduate Research in Marine and Coastal Sciences

This is a snapshot satellite image of sea surface temperature revealing some of the processes involved in Gulf stream flow along the coast. The inset shows a hammerhead shaped filament, possibly the remnant of an eddy, impinging on the shelf break. These features are important in cross shelf exchange processes and have recently been observed via CODAR influencing surface currents on the shelf. The picture below shows subsurface data for this general area.

Hydrographic profiles were collected with a CTD (right) equipped with a fluorometer and and OBS. Data for temperature, salinity, chlorophyll and OBS withdensity contoured in white is show to the left. These transects show a warm, fresh surface layer, a broad relatively fresh section of shelf water and possibly cold, salty Cold Pool water. The chlorophyll data shows some production under the plume as well as between the shelf and Cold Pool water.

ACKNOWLEDGEMENTSThe Coastal Ocean Observing Laboratory provided valuable expertise, data, and time to the RIOS project. This work would not have been possible without their help. In particular we thank Jen Bosh, Josh Kohut, and John Kerfoot for assistance. We also thank Bob Chant, John Manderson, Liz Sikes, Lee Kerkhoff, Jim Ammerman, Judy Grassle, Mike Deluca, John Quinlan, Marge Piechota, Lillian Lee, Brian Eng, Grant Law, Sara Bender, Clare Ng, the Captain and crew of the R/V Sorrenson Miller and everyone at IMCS for equipment and time. Finally, we thank IMCS and NSF for funding and support.

Alison Astalos - RU, Chris Ballew - Central Col., Adam Bohnert - Rhodes Col., James Bunkiewicz - RU, Sarah Edwards - UW Madison, Anirban Ghosh - Clarkson U, Elizabeth "Tucker" Hirsch - RU, Catherine Jedrzejczyk - Col. of NJ, Rachel Koehler - UW Stevens Pt., Angelique Linares - RU, Alicia Manoski - RU, Katherine Piso - RU, Paige Roberts - U of Miami and Rachel Sargent - UV