This PDF file contains the front matter associated with SPIE Proceedings Volume 7317, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

Many luminaries of oceanography have articulated the problem of adequately sampling a multiplicity of interdisciplinary ocean processes. Progress has accelerated within the past two decades as societal and naval interests in monitoring and predicting the state of the ocean environment has heightened. Oceanographers are capitalizing on a host of new platform and sensing technologies. Some recent programs contributing to improved 4-dimensional open and coastal ocean multi-disciplinary observations are used to highlight the development of new integrated optical, chemical, and physical measurement systems that can be deployed from stationary and mobile platforms to telemeter data in near real-time or real-time. For example, the NOPP O-SCOPE and MOSEAN projects have developed and tested several optical and chemical sensors in deep waters off Bermuda and Hawaii, at OWS 'P' in the North Pacific Ocean, and in coastal waters off Santa Barbara and Monterey, California. Most of the testing for these projects has been conducted using moorings; however, NOPP instrumentation is also being used on mobile platforms including AUVs, profiling floats, and gliders. Progress in adequately sampling the temporal and spatial variability of selected ocean 'sampling volumes' using multi-platform, multi-disciplinary sampling is described using examples from selected recent programs.

Current United States Navy Mine-Counter-Measure (MCM) operations primarily use electro-optical identification (EOID) sensors to identify underwater targets after detection via acoustic sensors. These EOID sensors which are based on laser underwater imaging by design work best in "clear" waters and are limited in coastal waters especially with strong optical layers. Optical properties and in particular scattering and absorption play an important role on systems performance. Surface optical properties alone from satellite are not adequate to determine how well a system will perform at depth due to the existence of optical layers. The spatial and temporal characteristics of the 3d optical variability of the coastal waters along with strength and location of subsurface optical layers maximize chances of identifying underwater targets by exploiting optimum sensor deployment. Advanced methods have been developed to fuse the optical measurements from gliders, optical properties from "surface" satellite snapshot and 3-D ocean circulation models to extend the two-dimensional (2-D) surface satellite optical image into a three-dimensional (3-D) optical volume with subsurface optical layers. Modifications were made to an EOID performance model to integrate a 3-D optical volume covering an entire region of interest as input and derive system performance field. These enhancements extend present capability based on glider optics and EOID sensor models to estimate the system's "image quality". This only yields system performance information for a single glider profile location in a very large operational region. Finally, we define the uncertainty of the system performance by coupling the EOID performance model with the 3-D optical volume uncertainties. Knowing the ensemble spread of EOID performance field provides a new and unique capability for tactical decision makers and Navy Operations.

The Naval Oceanographic Office (NAVOCEANO) Glider Operations Center (GOC) supported its first joint-mission exercise during Rim of the Pacific (RIMPAC) 08, a multi-national naval exercise conducted during July 2008 near the Hawaiian Islands. NAVOCEANO personnel deployed four Seagliders from USNS SUMNER for Anti-submarine Warfare (ASW) operations and four Slocum gliders for Mine Warfare (MIW) operations. Each Seaglider was equipped with a Sea-Bird Electronics (SBE) 41cp CTD and Wet Labs, Inc. bb2fl ECO-puck optical sensor. The instrumentation suite on the Slocum gliders varied, but each Slocum glider had an SBE 41cp CTD combined with one of the following optical sensors: a Wet Labs, Inc. AUVb scattering sensor, a Wet Labs, Inc. bb3slo ECO-puck backscattering sensor, or a Satlantic, Inc. OCR radiometer. Using Iridium communications, the GOC had command and control of all eight gliders, with Department of Defense (DoD) personnel and DoD contractors serving as glider pilots. Raw glider data were transmitted each time a glider surfaced, and the subsequent data flow included processing, quality-control procedures, and the generation of operational and tactical products. The raw glider data were also sent to the Naval Research Laboratory at Stennis Space Center (NRLSSC) for fusion with satellite data and modeled data (currents, tides, etc.) to create optical forecasting, optical volume, and electro-optical identification (EOID) performance surface products. The glider-based products were delivered to the ASW and MIW Reach Back Cells for incorporation into METOC products and for dissemination to the Fleet. Based on the metrics presented in this paper, the inaugural joint-mission operation was a success.

Buoyancy driven Slocum gliders were a vision of Douglas Webb, which Henry Stommel championed in a vision published in 1989. Slocum gliders have transitioned from a concept to a technology serving research and environmental stewardship. The long duration and low costs of gliders allow them to anchor spatial time series. Large distances, over 600 km, can be covered using a set of alkaline batteries. Lithium batteries can anchor missions that are thousands of kilometers in length. Since the initial tests, a wide range of physical and optical sensors have been integrated into the glider allowing measurements of temperature, salinity, depth averaged currents, surface currents, fluorescence, apparent/inherent optical properties active and passive acoustics. A command/control center, entitled Dockserver, has been developed that allows users to fly fleets of gliders simultaneously in multiple places around the world via the Internet. Since October 2003, Rutgers gliders have conducted 157 missions, traversed >55,000 kilometers, logged >2600 days at sea, and logged ~350,000 vertical profiles. The capabilities of the glider make them an indispensable tool for the growing global effort to build integrated ocean observatories. For example, gliders are now a central tool within the National Science Foundation Ocean Observatory Initiative (OOI) and the National Oceanic and Atmospheric Administration's Integrated Ocean Observing System (IOOS). Gliders provide a new magnet in which to attract young people into the ocean science and engineering. For example Rutgers undergraduates now anchor long duration flights of gliders world-wide beginning their freshmen year. This is critical to training the next generation.

We report on the design and evaluation of the initial results of operation of a prototype of an advanced system for maritime security. The system is autonomous and is designed to remain in the ocean for extended periods up to two months. It is based on the Bottom Stationing Ocean Profiler (BSOP), an un-tethered, autonomous platform that stations itself on the sea floor and ascends to the surface at specific time intervals or, potentially, when triggered by certain events such as recognizable acoustic signals, collected and analyzed on board. The surface operations of the system include optical data acquisition, image data analysis, communication with the ground station, and retrieval based functionality. The system is designed to take video and imagery of the surrounding ocean surface and analyze it for the presence of ships, thus, potentially enabling automatic detection and tracking of marine vehicles as they transit in the vicinity of the platform. The system transmits the data to the ground control via bi-directional RF satellite link and can have its mission parameters reprogrammed during the deployment. The described unit is low cost, easy to deploy and recover, and does not reveal itself to the potential targets. The paper describes the system hardware, architecture, algorithms for visual ship detection and tracking.

Imaging polarimetry can be used to accurately measure wave slopes of ocean waves in real time. An imaging polarimeter measures the polarization ellipse, and hence the degree of polarization and its orientation, by acquiring a number of images each of which analyzes a different polarization state. By knowing the geometry of the camera and its relationship to the sea surface and the measured polarization quantities, the wave slope can be extracted. We have developed and tested such an instrument with good results. For this talk, the four camera imaging polarimeter operating in the visible at 60 frames per second will be presented. The polarimeter design, calibration procedures, and the data from several data acquisition programs using the instrument will be presented.

Tracking of storm fronts in weather imagery is important for several weather-related applications. Coastal-area weather radars provide coverage up to 200-250 miles into the ocean, and thus can help with tracking of storm-fronts to support forecasting in those areas. Another application where tracking of storm fronts can be of assistance is clutter/rain classification. Specifically, the path of a tracked event can be used to decide if the particular event corresponds to precipitation or clutter. For instance, clutter usually appears to be a relatively static event. Precipitation can be modeled as a mixture of localized functions, each changing in terms of shape, position, and intensity. Tracking of precipitation events can be performed via tracking of the localized function parameters. In this paper, the modeling of rain events using Radial Basis Function neural networks (RBFNN) is studied. In the recent past, such techniques have been used for forecasting. Although effective, these techniques have been found to be computationally expensive. In this work, we evaluate the feasibility of modeling rain events using RBFNN in an efficient manner, and we propose modifications to existing techniques to achieve this goal.

Optical imaging and optical communications systems are limited in the underwater environment due to optical scattering. For an imaging system, light that scatters back to the receiver before reaching an underwater object degrades image contrast. Light that scatters multiple times on its way to and from the object of interest tends to blur the image and further reduce its contrast. This forward-scattered light may also ultimately limit the bandwidth of a point-to-point optical communications link. While continuous wave sources with low frequency modulation (<100MHz) and pulsed sources with several nanosecond pulse durations have been used to mitigate the backscatter problem, little has been done to study the effect of higher modulation frequencies (>100MHz) or short (<2nsec) pulse durations on forward-scattered light. The challenge has been the lack of hardware and theoretical models required to examine events at these short time scales. Fortunately, short pulse and modulated pulse sources have now been developed, along with optical receivers with sufficient bandwidth and sensitivity to measure the response of the water to these sources. The purpose of this work is to use these tools to study the propagation of modulated light fields at frequencies up to 1GHz. Results from laboratory tank experiments and their impact on future underwater optical imaging and communications systems will be discussed.

Experimental results from two alternate approaches to underwater imaging based around the well known Laser Line Scan (LLS) serial imaging technique are presented. Traditionally employing Continuous Wave (CW) laser excitation, LLS is known to improve achievable distance and image contrast in scattering-dominant waters by reducing both the backscatter and forward scatter levels reaching the optical receiver. This study involved designing and building prototype benchtop CW-LLS and pulsed-gated LLS imagers to perform a series of experiments in the Harbor Branch Oceanographic Institute (HBOI) full-scale laser imaging tank, under controlled scattering conditions using known particle suspensions. Employing fixed laser-receiver separation (24.3cm) in a bi-static optical geometry, the CW-LLS was capable of producing crisp, high contrast images at beyond 4 beam attenuation lengths at 7 meters stand-off distance. Beyond this stand-off distance or at greater turbidity, the imaging performance began to be limited mainly by multiple backscatter and shot noise generated in the receiver, eventually reaching a complete contrast limit at around 6 beam attenuation lengths. Using identical optical geometry as the CW-LLS, a pulsed-gated laser line scan (PG-LLS) system was configured and tested, demonstrating a significant reduction in the backscatter reaching the receiver. When compared with the CW-LLS at 7 meters stand-off distance, the PG-LLS did not become limited due to multiple backscatter, instead reaching a limit (believed to be primarily due to forward-scattered light overcoming the attenuated direct target signal) beyond 7 beam attenuation lengths. This result demonstrates the potential for a greater operational limit as compared to previous CW-LLS configuration.

Optical communication links using retro-reflectors underwater are investigated. In the retro-reflector geometry, backscattered light from turbid waters can interfere with the retro-reflected information signal. Presented here are polarization techniques to reduce the contribution of backscatter, as well as an evaluation on the impact of communication link range and reliability.

Polarization characteristics of coastal waters were recently measured during a cruise on the R/V "Connecticut" in the areas of New York Harbor - Sandy Hook, NJ region using a new Stokes vector instrument developed by the Optical Remote Sensing Laboratory at CCNY. The instrument has three hyperspectral Satlantic radiance sensors each with a polarizer positioned in front of it, with polarization axes aligned at 0, 90 and 45°. The measured degrees of polarization (DOPs) and normalized radiances as a function of angle and wavelength match very well with simulated ones obtained with a Monte Carlo radiative transfer code for the atmosphere-ocean system. In order to numerically reproduce the polarized images for underwater horizontal imaging system the measured typical underwater polarized radiance was used to estimate the polarized components of the background veiling light and the blurring effects were modeled by point spread functions obtained from the measured volume scattering functions from this cruise and other typical oceanic environments. It is shown that the visibility can be improved for unpolarized target by placing a polarizer oriented orthogonally to the partially polarized direction of the veiling light before camera. The blurring effects strongly depend on the small angle scattering in the forward directions. For polarized targets the Monte Carlo simulation of slab geometry for polarized pencil light shows that the scattering medium with high g value has a very strong ability to retain the polarization status of the incident light, which can be utilized to improve the image contrasts for targets with very different polarized reflection properties.

Diver visibility has been one of the key research areas in underwater vision and imaging studies. Its applications also extend into imaging system performance evaluation and prediction, which is important in MIW and ASW operations. These applications are often associated with coastal ocean waters, and this is generally translated directly into turbidity of the water column. While mostly this is the case, exceptions can lead to erroneous predictions and potentially significant consequences. We examine issues associated with such situations, both by model as well as field data, in order to reach better estimates and to explore means to compensate for such effects, to enhance diver visibility. Visibility data collected by Navy divers from clean and relatively calm waters outside Pensacola, during Sept 2001 Gorging Littoral Ocean for Warfighters (GLOW) experiments suggested a closer examination is warranted, as observed diver visibility measured at different spatial frequencies contradicts conventional model predictions. Observation data from two different days, by different divers at different depths were used. The modulation transfer of high frequency components disappears at a level much higher than those predicted by the human vision sensitivity level. Such contradictions can be resolved, once the effect of the turbulence scattering is considered using a general imaging model.

Advanced Coherent Technologies, LLC (ACT) is using a multi-spectral, multi-channel imaging system to detect and monitor marine mammals. The system, designed with US Navy funding, is intended to monitor mammals on US Navy submarine training ranges prior to and during Navy active acoustic training activities. ACT has conducted system tests and data collection activities at the St. Lawrence Seaway (Quebec, Canada), at Ma'alaea Bay (Maui, Hawaii), and from the Coronado Bay Bridge (San Diego, California). A description of the imaging system and the results of the data collections are discussed and presented.

Sea clutter, the radar backscatter from the ocean surface, is highly complicated and non-stationary, due to multipath propagation of the radar returns and multiscale interactions at the air-sea interface. To facilitate robust detection of low observable targets within sea clutter, which is an important issue in coastal security, navigation safety and environmental monitoring, we propose a systematic multiscale approach to the modeling of sea clutter. Specifically, we (i) develop new methods to better fit non-stationary and non-Gaussian sea clutter, (ii) fully characterize the correlation structure of sea clutter on multiple time scales, (iii) develop a highly accurate cascade model for sea clutter, and (iv) develop accurate and readily implementable methods to detect low observable targets within sea clutter.

In this paper the structure and operational features of C-band, multi-polarization, combined scatterometer-radiometer system and the results of preliminary, spatio-temporally collocated measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at ~5.6GHz are presented.

In this paper a measuring complex of C-, Ku and Ka-band, multi-polarization, combined scatterometer-radiometer systems, their structures and operational features, measuring platforms and calibration facilities are presented. As well as the results of preliminary, spatio-temporally collocated, multi-frequency and multi-polarization measurements of waved pool water surface microwave reflective (radar backscattering coefficient) and emissive (brightness temperature) characteristics angular dependences at 5,6GHz and 15GHz are presented.

The oil leakage of off-shore pipelines will cause ocean contamination and economic losses. These accidents may happen by the failures of offshore pipelines due to corrosion, impulse and free-spanning. So, it is very urgent on pipeline health monitoring. Fiber optic distributed sensors should be used to know when and where failures may occur. In this study, a feasibility of BOTDA (Brillouin Optical Time Domain Analysis) system is studied on off-shore pipeline distributed strain monitoring influenced by free spanning. Strain distribution of an off-shore pipeline is calculated by numerical analysis and strain measurement experiments are carried on a beam bending test using BOTDA system. BOTDA could be an excellent tool to monitor the long-distance pipeline.