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NASA NTRS2003

Plumes and Blooms: Observations, Analysis and Modeling for SIMBIOS

The goal of the Plumes and Blooms (PnB) project is to develop, validate and apply to imagery state-of-theart ocean color algorithms for quantifying sediment plumes and phytoplankton blooms for the Case I1 environment of the Santa Barbara Channel. We conduct monthly to twice-monthly transect observations across the Santa Barbara Channel to develop an algorithm development and product validation data set. The PnB field program started in the summer of 1996. At each of the 7 PnB stations, a complete verification bio-geo-optical data set is collected. Included are redundant measures of apparent optical properties (remote sensing reflectance and diffuse attenuation spectra), as well as in situ profiles of spectral absorption, beam attenuation and backscattering coefficients. Water samples are analyzed for component in vivo absorption spectra, fluorometric chlorophyll, phytoplankton pigment (by the SDSU CHORS laboratory), and inorganic nutrient concentrations (Table 1). A primary goal is to use the PnB field data set to objectively tune semi-analytical models of ocean color for this site and apply them using available satellite imagery (SeaWiFS and MODIS). In support of this goal, we have also been addressing SeaWiFS ocean color and AVHRR SST imagery (Otero and Siegel, 2003). We also are using the PnB data set to address time/space variability of water masses in the Santa Barbara Channel and its relationship to the 1997/1998 El Niiio. However, the comparison between PnB field observations and satellite estimates of primary products has been disappointing. We find that field estimates of water-leaving radiance, LwN(h), correspond poorly to satellite estimates for both SeaWiFS and MODIS local area coverage imagery. We believe this is due to poor atmospheric correction due to complex mixtures of aerosol types found in these near-coastal regions. Last, we remain active in outreach activities.

Siegel, D. A.↗
NASA NTRS2003

The Bermuda BioOptics Project (BBOP) Years 9-11

The Bermuda BioOptics Project (BBOP) is a collaborative effort between the Institute for Computational Earth System Science (ICESS) at the University of California at Santa Barbara (UCSB) and the Bermuda Biological Station for Research (BBSR). This research program is designed to characterize light availability and utilization in the Sargasso Sea, and to provide an optical link by which biogeochemical observations may be used to evaluate bio-optical models for pigment concentration, primary production, and sinking particle fluxes from satellite-based ocean color sensors. The BBOP time-series was initiated in 1992, and is carried out in conjunction with the U.S. JGOFS Bermuda Atlantic Time-series Study (BATS) at the Bermuda Biological Station for Research. The BATS program itself has been observing biogeochemical processes (primary productivity, particle flux and elemental cycles) in the mesotrophic waters of the Sargasso Sea since 1988. Closely affiliated with BBOP and BATS is a separate NASA-funded study of the spatial variability of biogeochemical processes in the Sargasso Sea using high-resolution AVHRR and SeaWiFS data collected at Bermuda. The collaboration between BATS and BBOP measurements has resulted in a unique data set that addresses not only the SIMBIOS goals but also the broader issues of important factors controlling the carbon cycle. This final report addresses specific research activities, research results, and lists of presentations and papers submitted for publication.

Nelson, Norm↗
NASA NTRS2003

Validation of an In-Water, Tower-Shading Correction Scheme

Large offshore structures used for the deployment of optical instruments can significantly perturb the intensity of the light field surrounding the optical measurement point, where different portions of the visible spectrum are subject to different shadowing effects. These effects degrade the quality of the acquired optical data and can reduce the accuracy of several derived quantities, such as those obtained by applying bio-optical algorithms directly to the shadow-perturbed data. As a result, optical remote sensing calibration and validation studies can be impaired if shadowing artifacts are not fully accounted for. In this work, the general in-water shadowing problem is examined for a particular case study. Backward Monte Carlo (MC) radiative transfer computations- performed in a vertically stratified, horizontally inhomogeneous, and realistic ocean-atmosphere system are shown to accurately simulate the shadow-induced relative percent errors affecting the radiance and irradiance data profiles acquired close to an oceanographic tower. Multiparameter optical data processing has provided adequate representation of experimental uncertainties allowing consistent comparison with simulations. The more detailed simulations at the subsurface depth appear to be essentially equivalent to those obtained assuming a simplified ocean-atmosphere system, except in highly stratified waters. MC computations performed in the simplified system can be assumed, therefore, to accurately simulate the optical measurements conducted under more complex sampling conditions (i.e., within waters presenting moderate stratification at most). A previously reported correction scheme, based on the simplified MC simulations, and developed for subsurface shadow-removal processing of in-water optical data taken close to the investigated oceanographic tower, is then validated adequately under most experimental conditions. It appears feasible to generalize the present tower-specific approach to solve other optical sensor shadowing problems pertaining to differently shaped deployment platforms, and also including surrounding structures and instrument casings.

Hooker, Stanford B.↗
NASA NTRS2003

Biomaterials and Magnetic fields for Cancer Therapy

The field of biomaterials has emerged as an important topic in the purview of NASA s new vision of research activities in the Microgravity Research Division. Although this area has an extensive track record in the medical field as borne out by the routine use of polymeric sutures, implant devices, and prosthetics, novel applications such as tissue engineering, artificial heart valves and controlled drug delivery are beginning to be developed. Besides the medical field, biomaterials and bio-inspired technologies are finding use in a host of emerging interdisciplinary fields such as self-healing and self-assembling structures, biosensors, fuel systems etc. The field of magnetic fluid technology has several potential applications in medicine. One of the emerging fields is the area of controlled drug delivery, which has seen its evolution from the basic oral delivery system to pulmonary to transdermal to direct inoculations. In cancer treatment by chemotherapy for example, targeted and controlled drug delivery has received vast scrutiny and substantial research and development effort, due to the high potency of the drugs involved and the resulting requirement to keep the exposure of the drugs to surrounding healthy tissue to a minimum. The use of magnetic particles in conjunction with a static magnetic field allows smart targeting and retention of the particles at a desired site within the body with the material transport provided by blood perfusion. Once so located, the therapeutical aspect (radiation, chemotherapy, hyperthermia, etc.) of the treatment, now highly localized, can be implemented.

Ramachandran, Narayanan↗
NASA NTRS2001

Multiple-Path-Length Optical Absorbance Cell

An optical absorbance cell that offers a selection of multiple optical path lengths has been developed as part of a portable spectrometric instrument that measures absorption spectra of small samples of water and that costs less than does a conventional, non-portable laboratory spectrometer. The instrument is intended, more specifically, for use in studying colored dissolved organic matter (CDOM) in seawater, especially in coastal regions. Accurate characterization of CDOM is necessary for building bio-optical mathematical models of seawater. The multiple path lengths of the absorption cell afford a wide range of sensitivity needed for measuring the optical absorbances associated with the wide range of concentrations of CDOM observed in nature. The instrument operates in the wavelength range of 370 to 725 nm. The major subsystems of the instrument (see figure) include a color-balanced light source; the absorption cell; a peristaltic pump; a high-precision, low-noise fiber optic spectrometer; and a laptop or other personal computer. A fiber-optic cable transmits light from the source to the absorption cell. Other optical fibers transmit light from the absorption cell to the spectrometer,

Source record↗
NASA NTRS2003

Actions, Observations, and Decision-Making: Biologically Inspired Strategies for Autonomous Aerial Vehicles

This paper details the development and demonstration of an autonomous aerial vehicle embodying search and find mission planning and execution srrategies inspired by foraging behaviors found in biology. It begins by describing key characteristics required by an aeria! explorer to support science and planetary exploration goals, and illustrates these through a hypothetical mission profile. It next outlines a conceptual bio- inspired search and find autonomy architecture that implements observations, decisions, and actions through an "ecology" of producer, consumer, and decomposer agents. Moving from concepts to development activities, it then presents the results of mission representative UAV aerial surveys at a Mars analog site. It next describes hardware and software enhancements made to a commercial small fixed-wing UAV system, which inc!nde a ncw dpvelopnent architecture that also provides hardware in the loop simulation capability. After presenting the results of simulated and actual flights of bioinspired flight algorithms, it concludes with a discussion of future development to include an expansion of system capabilities and field science support.

Pisanich, Greg↗
NASA NTRS2003

Field-effect Flow Control in Polymer Microchannel Networks

A new Bio-MEMS electroosmotic flow (EOF) modulator for plastic microchannel networks has been developed. The EOF modulator uses field-effect flow control (FEFC) to adjust the zeta potential at the Parylene C microchannel wall. By setting a differential EOF pumping rate in two of the three microchannels at a T-intersection with EOF modulators, the induced pressure at the intersection generated pumping in the third, field-free microchannel. The EOF modulators are able to change the magnitude and direction of the pressure pumping by inducing either a negative or positive pressure at the intersection. The flow velocity is tracked by neutralized fluorescent microbeads in the microchannels. The proof-of-concept of the EOF modulator described here may be applied to complex plastic ,microchannel networks where individual microchannel flow rates are addressable by localized induced-pressure pumping.

Sniadecki, Nathan↗
NASA NTRS2003

MODIS Validation, Data Merger and Other Activities Accomplished by the SIMBIOS Project: 2002-2003

The purpose of this technical report is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, satellite data processing, and data product validation. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report focuses on the SIMBIOS Project s efforts in support of the Moderate-Resolution Imaging Spectroradiometer (MODIS) on the Earth Observing System (EOS) Terra platform (similar evaluations of MODIS/Aqua are underway). This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project.

Fargion, Giulietta S.↗
NASA NTRS2003

Spatio-Temporal Distribution of Particulate and Dissolved Organic Matter in the Mississippi River Bight From Optical Measurements

The Mississippi River Bight is a highly dynamic region influenced by the seasonally variable outflow from the Mississippi River. In an effort to characterize the distribution of particulate and dissolved organic matter in the region, we conducted a two-year field program in the spring and fall (high and low flow river discharge) of 2000 and 2002. We collected a comprehensive set of bio-optical measurements consisting of vertical profiles (absorption, scattering, chlorophyll fluorescence and radiometry) and discrete measurements (pigment concentrations, particulate and CDOM absorption) that enabled us to obtain better insight into the seasonal and spatial variability of some important biogeochemical parameters. Our field measurements generally showed higher phytoplankton clorophyll concentrations in the plume waters (associated with lower surface salinities) and confirmed the high biological activity abserved in other studies. The seasonal flow of river discharge and advective currents due to wind forcing exerted a strong influence on the biological and optical properties of the region. An examination of absorption at 440 nm by the algal and non-algal fraction of the particulate pool and of CDOM revealed that at nearshore stations, contributions by the non-algal particles were high (about 40%) and decresed with increasing salinities. While CDOM absorption exhibited conservative mixing, its relative contribution to the total absorption was variable. Surface waters at most stations had lower salinities that generalliy increased with dept. Particulate matter and CDOM also decreased with depth as evidenced by absorption and scattering measurements. Good correlations in surface waters between concentrations of particulate and dissolved matter, the inherent optical properties of absorption and ackscattering and remote sensing reflectance values has allowed the development of robust empirical algorithms for phytoplankton chlorophyll and CDOM absorption.

DSa, E. J.↗
NASA NTRS2003

Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS "Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS , SeaWiFS, & Landsat. Feel the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center

Hasler, Fritz↗
NASA NTRS2003

Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS "Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS, SeaWiFS, & Landsat. Feel the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center

Hasler, Fritz↗
NASA NTRS2003

Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS 'Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS, SeaWiFS, & Landsat. Feel the pulse of OUT planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center.

Hasler, Fritz↗
NASA NTRS2003

Full-Waveform, Wide-Swath Lidar Imaging of Forested and Urban Areas in Leaf-On Conditions: Development, Results and Future Direction

Full-Waveform lidar measurements provide unprecedented views of the vertical and horizontal structure of vegetation and the topography of the Earth s surface. Utilizing a high signal-to-noise ratio lidar system, larger than typical laser footprints (10-20 m), and the recorded time history of interaction between a short-duration (approx. 10 ns) pulse of laser light and the surface of the Earth, full-waveform lidar is able to simultaneously image sub-canopy topography as well as the vertical structure of any overlying vegetation. These data reveal the true 3-D vegetation structure in leaf-on conditions enabling important biophysical parameters such as above-ground biomass to be estimated with unprecedented accuracy. An airborne lidar mission was conducted July-August 2003 in support of the North America Carbon Program. NASA s Laser Vegetation Imaging Sensor (LVIS) was used to image approximately 2,000 km$^2$ in Maine, New Hampshire, Massachusetts and Maryland. Areas with available ground and other data were included (e.g., experimental forests, FLUXNET sites) in order to facilitate as many bio- and geophysical investigations as possible. Data collected included ground elevation and canopy height measurements for each laser footprint, as well as the vertical distribution of intercepted surfaces. Data will be publicly distributed within 6- 12 months of collection. Further details of the mission, including the lidar system technology, the locations of the mapped areas, and examples of the numerous data products that can be derived from the return waveform data products will be presented. Future applications including detection of ground and vegetation canopy changes and a spaceborne implementation of wide-swath, full-waveform imaging lidar will also be discussed.

Blair, James B.↗
NASA NTRS2004

Initial Efforts toward Mission-Representative Imaging Surveys from Aerial Explorers

Numerous researchers have proposed the use of robotic aerial explorers to perform scientific investigation of planetary bodies in our solar system. One of the essential tasks for any aerial explorer is to be able to perform scientifically valuable imaging surveys. The focus of this paper is to discuss the challenges implicit in, and recent observations related to, acquiring mission-representative imaging data from a small fixed-wing UAV, acting as a surrogate planetary aerial explorer. This question of successfully performing aerial explorer surveys is also tied to other topics of technical investigation, including the development of unique bio-inspired technologies.

Pisanich, Greg↗
NASA NTRS2000

A Quantitative Study of Oxygen as a Metabolic Regulator

An acute reduction in oxygen delivery to a tissue is associated with metabolic changes aimed at maintaining ATP homeostasis. However, given the complexity of the human bio-energetic system, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). In particular, we are interested in determining mechanisms relating cellular oxygen concentration to observed metabolic responses at the cellular, tissue, organ, and whole body levels and in quantifying how changes in tissue oxygen availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study; we extend a previously developed mathematical model of human bioenergetics, to provide a physicochemical framework that permits quantitative understanding of oxygen as a metabolic regulator. Specifically, the enhancement - sensitivity analysis - permits studying the effects of variations in tissue oxygenation and parameters controlling cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The analysis can distinguish between parameters that must be determined accurately and those that require less precision, based on their effects on model predictions. This capability may prove to be important in optimizing experimental design, thus reducing use of animals.

Radhakrishnan, Krishnan↗
NASA NTRS2004

An Historical Search for Unfrozen Water at the Phoenix Landing Site

The goal of this work is to explore the history of the high-latitude subsurface in the latitude range of the Phoenix landing site (65-75 deg. N). The approach is to use time-marching climate models to search for times, locations, and depths where thick films of unfrozen water might periodically occur. Thick films of unfrozen water (as distinct from ubiquitous monolayer water) are interesting for two reasons. First, multi-layer films of water may be bio-available. Second, patterned ground may require the occurrence of thick films of unfrozen water to facilitate the migration of particles and the development of excess pore ice, as reported by the Odyssey Gamma Ray Spectrometer (GRS) results. For the purposes of this work, we define conditions adequate to establish thick films of unfrozen water to be T greater than 268 K, and RH greater than 0.5. We start with the need to understand the atmospheric pressure. Because of the fact that we're looking at high latitudes, the seasonal cap buffers surface temperature for some part of the year. That directly affects the subsurface thermal regime, at least in the uppermost meter where we will be

Zent, Aaron↗
NASA NTRS2003

SIMBIOS Project; 2003 Annual Report

The purpose of this technical report is to provide current documentation of the the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, NASA Research Announcement (NRA) research status, satellite data processing, data product validation, and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project. The SIMBIOS Science Team Principal Investigators (PIs) original contributions to this report are in chapters four and above. The purpose of these contributions is to describe the current research status of the SIMBIOS-NRA-99 funded research. The contributions are published as submitted, with the exception of minor edits to correct obvious grammatical or clerical errors.

McClain, Charles R.↗
NASA NTRS2003

Refinement of Protocols for Measuring the Apparent Optical Properties of Seawater

Ocean color satellite missions, like the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) or the Moderate Resolution Imaging Spectroradiometer (MODIS) projects, are tasked with acquiring a global ocean color data set, validating and monitoring the accuracy and quality of the data, processing the radiometric data into geophysical units using a set of atmospheric and bio-optical algorithms, and distributing the final products to the scientific community. The long-standing requirement of the SeaWiFS Project, for example, is to produce spectral water-leaving radiances, LW(lambda), to within 5% absolute (lambda denotes wavelength) and chlorophyll a concentrations to within 35% (Hooker and Esaias 1993), and most ocean color sensors have the same or similar requirements. Although a diverse set of activities are required to ensure the accuracy requirements are met (Hooker and McClain 2000), the perspective here is with field observations. The accurate determination of upper ocean apparent optical properties (AOPs) is essential for the vicarious calibration of ocean color data and the validation of the derived data products, because the sea-truth measurements are used to evaluate the satellite observations (Hooker and McClain 2000). The uncertainties with in situ AOP measurements have various sources: a) the sampling procedures used in the field, including the environmental conditions encountered; b) the absolute characterization of the radiometers in the laboratory; c) the conversion of the light signals to geophysical units in a processing scheme, and d) the stability of the radiometers in the harsh environment they are subjected to during transport and use. Assuming ideal environmental conditions, so this aspect can be neglected, the SeaWiFS ground-truth uncertainty budget can only be satisfied if each uncertainty is on the order of 1-2%, or what is generally referred to as 1% radiometry. In recent years, progress has been made in estimating the magnitude of some of these uncertainties and in defining procedures for minimizing them. For the SeaWiFS Project, the first step was to convene a workshop to draft the SeaWiFS Ocean Optics Protocols (hereafter referred to as the Protocols). The Protocols initially adhered to the Joint Global Ocean Flux Study (JGOFS) sampling procedures (JGOFS 1991) and defined the standards for optical measurements to be used in SeaWiFS calibration and validation activities (Mueller and Austin 1992). Over time, the Protocols were revised (Mueller and Austin 1995), and then recurringly updated on essentially an annual basis (Mueller 2000, 2002, and 2003) as part of the Sensor Inter-comparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) project. 98

Hooker, Stanford B.↗