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1

Shifting the paradigm of coral-reef ‘health’ assessment  

Microsoft Academic Search

Coral reefs are in crisis. Globally, our reefs are degrading at an accelerating rate and present methodologies for coral-reef ‘health’ assessment, although providing important information in describing these global declines, have been unable to halt these declines. These assessments are usually employed with no clear purpose and using uncorrelated methods resulting in a failure to prevent or mitigate coral reef

Craig A. Downs; Cheryl M. Woodley; Robert H. Richmond; Lynda L. Lanning; Richard Owen

2005-01-01

2

Linking coral reef health and human welfare  

E-print Network

shifts on coral reefs: scientific issues and managementin Kenyan coral reef lagoons: the role of reef management.management. Major contribution in Responding to global change: a reef manager’s guide to coral

Walsh, Sheila Marie

2009-01-01

3

-Congressional Policy Brief -Coral Reefs: For Health, For Wealth, For Life  

E-print Network

- Congressional Policy Brief - Coral Reefs: For Health, For Wealth, For Life Table of Contents Introduction ­ 1 What are Corals and Coral Reefs? ­ 1 Coral Reef Biology ­ 2 Hazards to Coral Reefs ­ 2 Major Reef-building Coral Diseases ­ 3 Coral Bleaching ­ 4 References and Resource Links ­ 4 "The

4

TEMPORAL TRENDS IN THE HEALTH OF SOUTH FLORIDA CORAL REEFS  

EPA Science Inventory

Barron, M.G., D.L. Santavy, L. MacLaughlin, E. Mueller, E. Peters, B. Quarles and J. Campbell. In press. Temporal Trends in the Health of South Florida Coral Reefs (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R100...

5

Environmental quality and preservation; reefs, corals, and carbonate sands; guides to reef-ecosystem health and environment  

USGS Publications Warehouse

Introduction In recent years, the health of the entire coral reef ecosystem that lines the outer shelf off the Florida Keys has declined markedly. In particular, loss of those coral species that are the building blocks of solid reef framework has significant negative implications for economic vitality of the region. What are the reasons for this decline? Is it due to natural change, or are human activities (recreational diving, ship groundings, farmland runoff, nutrient influx, air-borne contaminants, groundwater pollutants) a contributing factor and if so, to what extent? At risk of loss are biologic resources of the reefs, including habitats for endangered species in shoreline mangroves, productive marine and wetland nurseries, and economic fisheries. A healthy reef ecosystem builds a protective offshore barrier to catastrophic wave action and storm surges generated by tropical storms and hurricanes. In turn, a healthy reef protects the homes, marinas, and infrastructure on the Florida Keys that have been designed to capture a lucrative tourism industry. A healthy reef ecosystem also protects inland agricultural and livestock areas of South Florida whose produce and meat feed much of the United States and other parts of the world. In cooperation with the National Oceanic and Atmospheric Administration's (NOAA) National Marine Sanctuary Program, the U.S. Geological Survey (USGS) continues longterm investigations of factors that may affect Florida's reefs. One of the first steps in distinguishing between natural change and the effects of human activities, however, is to determine how coral reefs have responded to past environmental change, before the advent of man. By so doing, accurate scientific information becomes available for Marine Sanctuary management to understand natural change and thus to assess and regulate potential human impact better. The USGS studies described here evaluate the distribution (location) and historic vitality (thickness) of Holocene reefs in South Florida, relative to type of underlying bedrock morphology, and their varied natural response to rising sea level. These studies also assess movement and accumulation of sands, relative to direction of prevailing energy, and origin of the component sand grains. Geophysical data collected with highresolution sound-wave instruments that provide pictures of the sediment and bedrock are used to interpret sediment thickness. Reef thickness is determined by collecting limestone rock cores by drilling. Drill cores through reefs are used to identify the coral species that built them and to determine how reefs reacted to rising sea level. These data are supplemented by using isotope-dating techniques to derive the carbon-14 (C14) age of the corals and mangrove peat in the cores. Mangrove peat forms in very shallow water and at the shoreline but is found today buried beneath offshore reefs.

Lidz, Barbara H.

2001-01-01

6

New mapping techniques help assess the health of Hawaii's coral reefs  

USGS Publications Warehouse

The U.S. Geological Survey (USGS) is working closely with academic institutions and state and Federal agencies to assess the factors that affect the health of Hawaii's and our Nation's coral reefs. In order to establish a basis from which scientists can objectively detect changes in reef health, the USGS and its cooperators are applying many new techniques to the mapping and monitoring of coral reefs in Hawaii.

Field, M.E.; Chavez, P.S., Jr.; Evans, K.R.; Cochran, S.A.

2001-01-01

7

Turning science into health solutions: KEMRI’s challenges as Kenya’s health product pathfinder  

Microsoft Academic Search

BACKGROUND: A traditional pathway for developing new health products begins with public research institutes generating new knowledge, and ends with the private sector translating this knowledge into new ventures. But while public research institutes are key drivers of basic research in sub-Saharan Africa, the private sector is inadequately prepared to commercialize ideas that emerge from these institutes, resulting in these

Ken Simiyu; Hassan Masum; Justin Chakma; Peter A Singer

2010-01-01

8

Turning science into health solutions: KEMRI’s challenges as Kenya’s health product pathfinder  

PubMed Central

Background A traditional pathway for developing new health products begins with public research institutes generating new knowledge, and ends with the private sector translating this knowledge into new ventures. But while public research institutes are key drivers of basic research in sub-Saharan Africa, the private sector is inadequately prepared to commercialize ideas that emerge from these institutes, resulting in these institutes taking on the role of product development themselves to alleviate the local disease burden. In this article, the case study method is used to analyze the experience of one such public research institute: the Kenya Medical Research Institute (KEMRI). Discussion Our analysis indicates that KEMRI’s product development efforts began modestly, and a manufacturing facility was constructed with a strategy for the facility’s product output which was not very successful. The intended products, HIV and Hepatitis B diagnostic kits, had a short product life cycle, and an abrupt change in regulatory requirements left KEMRI with an inactive facility. These problems were the result of poor innovation management capacity, variability in domestic markets, lack of capital to scale up technologies, and an institutional culture that lacked innovation as a priority. However, KEMRI appears to have adapted by diversifying its product line to mitigate risk and ensure continued use of its manufacturing facility. It adopted an open innovation business model which linked it with investors, research partnerships, licensing opportunities, and revenue from contract manufacturing. Other activities that KEMRI has put in place over several years to enhance product development include the establishment of a marketing division, development of an institutional IP policy, and training of its scientists on innovation management. Summary KEMRI faced many challenges in its attempt at health product development, including shifting markets, lack of infrastructure, inadequate financing, and weak human capital with respect to innovation. However, it overcame them through diversification, partnerships and changes in culture. The findings could have implications for other research institutes in Sub-Saharan Africa seeking to develop health products. Such institutes must analyze potential demand and uptake, yet be prepared to face the unexpected and develop appropriate risk-mitigating strategies. PMID:21144070

2010-01-01

9

Reef Check  

NSDL National Science Digital Library

Reef Check, headquartered at the Institute of the Environment at the University of California Los Angeles, is a "volunteer, community-based monitoring protocol designed to measure the health of coral reefs on a global scale." With scientific reef surveys conducted in over 60 countries and territories, Reef Check has been able to track global trends in reef health to better inform possible conservation strategies. Visitors to the Reef Check Web site can read result summaries for the 1997-2001 monitoring period, and check out the organization's current and archived newsletters. Other resources include information on survey methods, Reef Check publications, a species identification guide, and other resources geared mainly toward Reef Check volunteers.

10

The health and future of coral reef systems  

Microsoft Academic Search

Coral reefs are among the most productive and diverse ecosystems on earth and provide a multitude of valuable ecosystem services. Moreover, the resources derived from coral reefs are essential to the food security of millions of people living within tropical coastal communities. Unfortunately, burgeoning human populations in coastal regions are placing an unsustainable burden on these resources such that degradation

David W Souter; Olof Lindén

2000-01-01

11

Pathfinders: Science  

NSDL National Science Digital Library

The Indianapolis Marion County Public Library provides these educational subject specific pathfinders "that contain a list of library materials, web sites, and other information about a topic." The Science section includes topics focused on how the human body works, including the circulatory, digestive, excretory, muscular, nervous, respiratory, and skeletal systems. Each topic includes a detailed diagram and facts about the body system, and a variety of helpful books and online resources appropriate for children. This site is a useful resource for gathering information on a specific subject or browsing a variety of topics.

12

Abrolhos Bank Reef Health Evaluated by Means of Water Quality, Microbial Diversity, Benthic Cover, and Fish Biomass Data  

PubMed Central

The health of the coral reefs of the Abrolhos Bank (southwestern Atlantic) was characterized with a holistic approach using measurements of four ecosystem components: (i) inorganic and organic nutrient concentrations, [1] fish biomass, [1] macroalgal and coral cover and (iv) microbial community composition and abundance. The possible benefits of protection from fishing were particularly evaluated by comparing sites with varying levels of protection. Two reefs within the well-enforced no-take area of the National Marine Park of Abrolhos (Parcel dos Abrolhos and California) were compared with two unprotected coastal reefs (Sebastião Gomes and Pedra de Leste) and one legally protected but poorly enforced coastal reef (the “paper park” of Timbebas Reef). The fish biomass was lower and the fleshy macroalgal cover was higher in the unprotected reefs compared with the protected areas. The unprotected and protected reefs had similar seawater chemistry. Lower vibrio CFU counts were observed in the fully protected area of California Reef. Metagenome analysis showed that the unprotected reefs had a higher abundance of archaeal and viral sequences and more bacterial pathogens, while the protected reefs had a higher abundance of genes related to photosynthesis. Similar to other reef systems in the world, there was evidence that reductions in the biomass of herbivorous fishes and the consequent increase in macroalgal cover in the Abrolhos Bank may be affecting microbial diversity and abundance. Through the integration of different types of ecological data, the present study showed that protection from fishing may lead to greater reef health. The data presented herein suggest that protected coral reefs have higher microbial diversity, with the most degraded reef (Sebastião Gomes) showing a marked reduction in microbial species richness. It is concluded that ecological conditions in unprotected reefs may promote the growth and rapid evolution of opportunistic microbial pathogens. PMID:22679480

Bruce, Thiago; Meirelles, Pedro M.; Garcia, Gizele; Paranhos, Rodolfo; Rezende, Carlos E.; de Moura, Rodrigo L.; Filho, Ronaldo-Francini; Coni, Ericka O. C.; Vasconcelos, Ana Tereza; Amado Filho, Gilberto; Hatay, Mark; Schmieder, Robert; Edwards, Robert; Dinsdale, Elizabeth; Thompson, Fabiano L.

2012-01-01

13

Assessment of the Water Quality and Ecosystem Health of the Great Barrier Reef (Australia): Conceptual Models  

NASA Astrophysics Data System (ADS)

Run-off containing increased concentrations of sediment, nutrients, and pesticides from land-based anthropogenic activities is a significant influence on water quality and the ecologic conditions of nearshore areas of the Great Barrier Reef World Heritage Area, Australia. The potential and actual impacts of increased pollutant concentrations range from bioaccumulation of contaminants and decreased photosynthetic capacity to major shifts in community structure and health of mangrove, coral reef, and seagrass ecosystems. A detailed conceptual model underpins and illustrates the links between the main anthropogenic pressures or threats (dry-land cattle grazing and intensive sugar cane cropping) and the production of key contaminants or stressors of Great Barrier Reef water quality. The conceptual model also includes longer-term threats to Great Barrier Reef water quality and ecosystem health, such as global climate change, that will potentially confound direct model interrelationships. The model recognises that system-specific attributes, such as monsoonal wind direction, rainfall intensity, and flood plume residence times, will act as system filters to modify the effects of any water-quality system stressor. The model also summarises key ecosystem responses in ecosystem health that can be monitored through indicators at catchment, riverine, and marine scales. Selected indicators include riverine and marine water quality, inshore coral reef and seagrass status, and biota pollutant burdens. These indicators have been adopted as components of a long-term monitoring program to enable assessment of the effectiveness of change in catchment-management practices in improving Great Barrier Reef (and adjacent catchment) water quality under the Queensland and Australian Governments’ Reef Water Quality Protection Plan.

Haynes, David; Brodie, Jon; Waterhouse, Jane; Bainbridge, Zoe; Bass, Deb; Hart, Barry

2007-12-01

14

Coral Reefs Coral Reefs  

E-print Network

1 Coral Reefs Coral Reefs Coral Reef Formation Scleractinian Coral Polyps · Scleractinia = stony Growth Reef Building Corals · Reef building corals are colonial ­ create large 'coral heads' that may productivity. ­ So no phytoplankton ­ So no zooplankton ­ So no food for corals Reef Building Corals

Cochran-Stafira, D. Liane

15

Mapping Health of Bonaire Coral Reefs Using a Lightweight Hyperspectral Mapping System - First Results  

NASA Astrophysics Data System (ADS)

The Dutch Caribbean island of Bonaire is one of the world's top diving holiday destinations much due to its clear waters and healthy coral reefs. The coral reefs surround the western side of the island as an approximately 50-150m wide band. However, the general consensus is that the extent and biodiversity of the Bonarian coral reef is constantly decreasing due to anthropogenic pressures. The last extensive study of the health of the reef ecosystem was performed in 1985 by Van Duyl creating an underwater atlas. In order to update this atlas of Bonaire's coral reefs, in October 2013, a hyperspectral mapping campaign was performed using the WUR Hyperspectral Mapping System (HYMSY). A dive validation campaign has been planned for early 2014. The HYMSY consists of a custom pushbroom spectrometer (range 450-950nm, FWHM 9nm, ~20 lines/s, 328 pixels/line), a consumer camera (collecting 16MPix raw image every 2 seconds), a GPS-Inertia Navigation System (GPS-INS), and synchronization and data storage units. The weight of the system at take-off is 2.0kg allowing it to be mounted on varying platforms. In Bonaire the system was flown on two platforms. (1) on a Cessna airplane to provide a coverage for whole west side of the island with a hyperspectral map in 2-4m resolution and a RGB orthomosaic in 15cm resolution, and (2) on a kite pulled by boat and car to provide a subset coverage in higher resolution. In this presentation we will present our mapping technique and first results including a preliminary underwater atlas and conclusions on reef development.

Suomalainen, Juha; Mucher, Sander; Kooistra, Lammert; Meesters, Erik

2014-05-01

16

Use of Integrated Landscape Indicators to Evaluate the Health of Linked Watersheds and Coral Reef Environments in the Hawaiian Islands  

NASA Astrophysics Data System (ADS)

A linkage between the condition of watersheds and adjacent nearshore coral reef communities is an assumed paradigm in the concept of integrated coastal management. However, quantitative evidence for this "catchment to sea" or "ridge to reef" relationship on oceanic islands is lacking and would benefit from the use of appropriate marine and terrestrial landscape indicators to quantify and evaluate ecological status on a large spatial scale. To address this need, our study compared the Hawai`i Watershed Health Index (HI-WHI) and Reef Health Index (HI-RHI) derived independently of each other over the past decade. Comparisons were made across 170 coral reef stations at 52 reef sites adjacent to 42 watersheds throughout the main Hawaiian Islands. A significant positive relationship was shown between the health of watersheds and that of adjacent reef environments when all sites and depths were considered. This relationship was strongest for sites facing in a southerly direction, but diminished for north facing coasts exposed to persistent high surf. High surf conditions along the north shore increase local wave driven currents and flush watershed-derived materials away from nearshore waters. Consequently, reefs in these locales are less vulnerable to the deposition of land derived sediments, nutrients and pollutants transported from watersheds to ocean. Use of integrated landscape health indices can be applied to improve regional-scale conservation and resource management.

Rodgers, Ku`ulei S.; Kido, Michael H.; Jokiel, Paul L.; Edmonds, Tim; Brown, Eric K.

2012-07-01

17

Effects of changing temperatures on coral reef health: Implications for management  

NASA Astrophysics Data System (ADS)

Human-induced climate change has already led to substantial changes in a variety of ecosystems. Coral reefs are particularly vulnerable to rises in ocean temperature as a result of climate change because they already live near their thermal limits. However, we know little about the spatial patterns of temperature anomalies, areas of greater than usual temperature, which cause coral mortality and increased rates of coral disease. These gaps in knowledge make it difficult to design effective management strategies for mitigating the effects of ocean warming. My dissertation research uses a combination of a new satellite ocean temperature dataset, field surveys on coral health, and data on marine protected area (MPA) boundaries to analyze how ocean temperatures are affecting coral reef health at regional and global scales. I discovered that temperature anomalies are spatially and temporally variable from 1985-2005 even during El Nino events. They are also typically less than 50 km2, smaller than the resolution of many climate models. In addition, I found a strong relationship on the Great Barrier Reef between the number of temperature anomalies and the number of cases of white syndrome, a prevalent coral disease. Results from this study suggest that temperature anomalies are playing a major role in the observed decline of coral reefs over the last 30-40 years. This decline highlights the importance of determining whether MPAs, one of the most common management tools are effective in restoring coral cover. My analyses demonstrated that MPAs can confer some ecosystem resilience through fisheries management and land management practices at regional scales. Coral cover on reefs inside of MPAs did not change over time, while unprotected reefs experienced declines in coral cover. However, MPAs do not moderate the effect of thermal stress on corals or reduce coral decline at rates that can offset losses from thermal stress and other major natural and human-caused disturbances. MPAs are clearly a key tool in the management of fisheries and coral reef health. My dissertation research underscores the need for both MPAs and additional measures aimed at reducing the anthropogenic activities driving climate change.

Selig, Elizabeth Rose

18

Clues to Coral Reef Health: Integrating Radiative Transfer Modeling and Hyperspectral Data  

NASA Technical Reports Server (NTRS)

An important contribution to coral reef research is to improve spectral distinction between various health states of coral species in areas subject to harmful anthropogenic activity and climate change. New insights into radiative transfer properties of corals under healthy and stressed conditions can advance understandings of ecological processes on reefs and allow better assessments of the impacts of large-scale bleaching and disease events, Our objective was to examine the spectral and spatial properties of hyperspectral sensors that may be used to remotely sense changes in reef community health. We compare in situ reef environment spectra (healthy coral, stressed coral, dead coral, algae, and sand) with airborne hyperspectral data to identify important spectral characteristics and indices. Additionally, spectral measurements over a range of water depths, relief, and bottom types are compared to help quantify bottom-water column influences. In situ spectra were collected in July and August 2002 at the Long Rock site in the Andros Island, Bahamas coastal zone coral reef. Our primary emphasis was on Acropora palmata (or elkhorn coral), a major reef building coral, which is prevalent in the study area, but is suffering from white band disease. A. palmata is currently being, proposed as an endangered species because its populations have severely declined in many areas of the Caribbean. In addition to the A. palmata biotope, we have collected spectra of at least seven other coral biotopes that exist within the study area, each with different coral community composition, density of corals, relief, and size of corals. Coral spectral reflectance was then input into a radiative transfer model, CORALMOD (CM1), which is based on a leaf radiative transfer model. In CM1, input coral reflectance measurements produce modeled reflectance through an inversion at each visible wavelength to provide the absorption spectrum. Initially, we imposed a scattering baseline that is the same regardless of the coral condition and that coral is optically thick and no light is transmitted through coral. Here we will focus on methodology, experimental design, and initial findings of the in situ spectral measurements and preliminary output from the radiative transfer model.

Guild, Liane; Ganapol, Barry; Kramer, Philip; Armstrong, Roy; Gleason, Art; Torres, Juan; Johnson, Lee; Garfield, Toby; Peterson, David L. (Technical Monitor)

2002-01-01

19

Pathfinder: Humans in space  

NASA Technical Reports Server (NTRS)

Viewgraphs are presented on the Pathfinder program. Information is given on human exploration of the solar system, technical requirements interfaces, program objectives, space suits, human performance, man-machine systems, space habitats, life support systems, and artificial gravity

Anderson, John L.

1988-01-01

20

Coral Reefs Under Stress  

NSDL National Science Digital Library

Coral reefs are more critical to an oceanâ??s health than you might think, and the effects of climate change and ocean acidification are effectively damaging and destroying most reefs in the world. Coral reefs provide many important ecosystem services, including: providing food, shelter, and meeting places for thousands of animals; anchoring sand for recreational beaches; and supplying building materials for remote peoples.

Peter Mumby (University of Exeter; )

2009-10-05

21

Pathfinder aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder is shown flying low over Rogers Dry Lakebed at Edwards Air Force Base. Its wing is very flexible, while its upper surface is covered with solar cells. While at high altitude, the vehicle was controlled by a remote pilot on the ground, but when the concept is fully developed, a vehicle larger than but similar to Pathfinder may be able to stay aloft for months at a time, without landing and with only sunlight as its 'fuel.'

1995-01-01

22

PathFinder Science  

NSDL National Science Digital Library

PathFinder Science contains research projects about water conservation, tardigrades, a winter bird survey, ozone, ultraviolet light and DNA, global warming, spot removal, lichens, stream monitoring, amphibian biomonitoring, and particulate monitoring. Free registration to the PathFinder Science Network offers the opportunity to be a part of the listserv, upload collaborative project data or publish research work. There are tools and tips to help students publish their research on the web.

23

Jurassic Reef Park  

NSDL National Science Digital Library

This is a bilingual, educational website from Munich, Germany. The main feature is a virtual field trip to the reefs of the Jurassic period. Besides a view of the Jurassic reefs, their builders, and their ecological settings, there is also an emphasis on the importance of modern reefs as indicators of the state-of-health of the globe and evidence of how some changes in the composition of reefs may represent the forerunners of catastrophic, regional or global, environmental change.

Reinhold Leinfelder

24

NOAA's Coral Reef  

NSDL National Science Digital Library

In an effort to centralize information on Coral Reefs, the National Oceanic and Atmospheric Administration (NOAA) has launched this site on Coral Reefs. The site serves both as a news resource (see the frequently updated News Releases section) as well as a basic information resource (see Year of the Reef 1997 and Coral Reef Photos) on coral reefs. For information on current research (scientific and citizen), see the Coral Health and Monitoring Program, the Great American Fish Count, or the Coral Reef Initiative sections. Additionally, a dozen Coral Reef Links point users to further resources. For the pure enthusiast or beginning college student, this site serves as a fine entry-way into learning about Coral Reefs.

25

The LISA Pathfinder Mission  

NASA Astrophysics Data System (ADS)

LISA Pathfinder, the second of the European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology verification mission for future space-borne gravitational wave detectors. LISA Pathfinder essentially mimics one arm of a gravitational wave detector by shrinking the million kilometre-scale armlength down to a few tens of centimetres, giving up the sensitivity to gravitational waves, but keeping the measurement technology. The experimental concept is to measure the relative separation between two test masses nominally following their own geodesics, and thereby determine the relative residual acceleration between them over timescales of ~1000seconds. In this paper I will present the LPF mission concept, the status of the mission, and the route from LISA Pathfinder to future gravitational wave missions.

McNamara, Paul

26

Reef grief  

NASA Astrophysics Data System (ADS)

As the first of the world's ecosystems faces extermination at our hands, coral reef ecologist Peter Sale -- Assistant Director of the Institute of Water, Environment and Health at the United Nations University in Ontario, Canada, and author of Our Dying Planet (published this autumn) -- talks to Nature Climate Change.

2011-10-01

27

Pathfinder: A Retrospective  

NASA Technical Reports Server (NTRS)

Mars is one of the most interesting planets in the solar system, featuring enormous canyons, giant volcanoes, and indications that, early in its history, it might have had rivers and perhaps even oceans. Five years ago, in July of 1997, the Pathfinder mission landed on Mars, bringing with it the microwave-oven sized Sojourner rover to wander around on the surface and analyse rocks. Among the experiments on the mission was one designed to analyse dust deposition. Pathfinder is only the first of an armada of spacecraft which will examine Mars from the pole to the equator in the next decade, culminating with a mission to bring humans to Mars.

Landis, Geoffrey A.; Lyons, Valerie (Technical Monitor)

2002-01-01

28

Clues to Coral Reef Ecosystem Health: Spectral Analysis Coupled with Radiative Transfer Modeling  

Microsoft Academic Search

Coral reefs are among the world's most productive and biologically rich ecosystems and are some of the oldest ecosystems on Earth. Coralline structures protect coastlines from storms, maintain high diversity of marine life, and provide nurseries for marine species. Coral reefs play a role in carbon cycling through high rates of organic carbon metabolism and calcification. Coral reefs provide fisheries

L. Guild; B. Ganapol; P. Kramer; R. Armstrong; A. Gleason; J. Torres; L. Johnson; N. Garfield

2003-01-01

29

Health of the coral reefs at the US Navy Base, Guantánamo Bay, Cuba: a preliminary report based on isotopic records from gorgonians.  

PubMed

Specimens of the gorgonian Plexaura homomalla were sampled from several areas along the fringing reefs fronting the United States Naval Base at Guantánamo Bay, Cuba. Sample coverage extended from apparently healthy reefs in oceanic waters to declining reefs located in the plume of the drainage from upper parts of Guantánamo Bay. Tentacle tips were excised, and trunk sections were cut and polished. Stable isotope ratios of nitrogen (?(15)N) and carbon indicate a strong correlation of reef health with proximity to the plume of the river. Of all the worldwide cases in which land-based sources of pollution have impacted reefs, this one may well be the most intractable. The US Navy has jurisdiction over the reefs, with the obligation to protect them, yet the threat comes down the river from Cuba. PMID:24735775

Risk, Michael J; Burchell, Meghan; Brunton, Dalston A; McCord, Michael R

2014-06-15

30

The Pathfinder Microrover  

NASA Technical Reports Server (NTRS)

An exciting scientific component of the Pathfinder mission is the rover, which will act as a mini-field geologist by providing us with access to samples for chemical analyses and close-up images of the Martian surface, performing active experiments to modify the surface and study the results, and exploring the landing site area.

Matijevic, J. R.; Bickler, D. B.; Braun, D. F.; Eisen, H. J.; Matthies, L. H.; Mishkin, A. H.; Stone, H. W.; van Nieuwstadt, L. M.; Wen, L. C.; Wilcox, B. H.; Ferguson, D.; Landis, G. A.; Oberle, L.

1996-01-01

31

Pathfinder Series Sexual Harassment  

E-print Network

Pathfinder Series Sexual Harassment Online Periodical Indexes (httpInfo Periodical Articles Byrne, John A. "Sexual Harassment at McKinsey?" Business Week 3505 (Dec. 9, 1996 in Worker's Attitudes Toward Sexual Harassment." Journal of Psychology 130:6 (Nov. 1996):627- . (BF1 .J67

Kearfott, R. Baker

32

Assessing community values for reducing agricultural emissions to improve water quality and protect coral health in the Great Barrier Reef  

NASA Astrophysics Data System (ADS)

Policymakers wanting to increase protection of the Great Barrier Reef from pollutants generated by agriculture need to identify when measures to improve water quality generate benefits to society that outweigh the costs involved. The research reported in this paper makes a contribution in several ways. First, it uses the improved science understanding about the links between management changes and reef health to bring together the analysis of costs and benefits of marginal changes, helping to demonstrate the appropriate way of addressing policy questions relating to reef protection. Second, it uses the scientific relationships to frame a choice experiment to value the benefits of improved reef health, with the results of mixed logit (random parameter) models linking improvements explicitly to changes in "water quality units." Third, the research demonstrates how protection values are consistent across a broader population, with some limited evidence of distance effects. Fourth, the information on marginal costs and benefits that are reported provide policymakers with information to help improve management decisions. The results indicate that while there is potential for water quality improvements to generate net benefits, high cost water quality improvements are generally uneconomic. A major policy implication is that cost thresholds for key pollutants should be set to avoid more expensive water quality proposals being selected.

Rolfe, John; Windle, Jill

2011-12-01

33

Pathfinder Air Bags  

NASA Technical Reports Server (NTRS)

Engineers test huge, multi-lobed air bags, which will envelope and protect the Mars Pathfinder spacecraft before it impacts the surface of Mars. The air bags, manufactured by ILC Dover of Frederica, Delaware, are composed of four large bags with six smaller, interconnected spheres within each bag. The bags measure 5 meters (17 feet) tall and about 5 meters (17 feet) in diameter. As Pathfinder is descending to the Martian surface on a parachute, an onboard altimeter inside the lander will monitor its distance from the ground. The computer will inflate these large air bags about 100 meters (330 feet) above the surface of Mars. ILC Dover is the same company that manufactures spacesuits.

1995-01-01

34

The LISA Pathfinder Mission  

NASA Astrophysics Data System (ADS)

Laser Interferometer Space Antenna (LISA) Pathfinder (formerly known as SMART-2) is a European Space Agency mission designed to pave the way for the joint ESA/NASA LISA mission by testing in flight the critical technologies required for space borne gravitational wave detection; it will put two test masses in a near-perfect gravitational free-fall and control and measure their motion with unprecedented accuracy. This is achieved through technology comprising inertial sensors, high precision laser metrology, drag-free control and an ultra precise micro-Newton propulsion system. LISA Pathfinder (LPF) essentially mimics one arm of space-borne gravitational wave detectors by shrinking the million kilometer scale armlengths down to a few tens of centimeters, giving up the sensitivity to gravitational waves, but keeping the measurement technology. The scientific objective of the LPF mission consists then of the first in-flight test of low frequency gravitational wave detection metrology.

McNamara, Paul W.

2013-01-01

35

VR for Mars Pathfinder  

NASA Technical Reports Server (NTRS)

Virtual reality (VR) technology has played an integral role for Mars Pathfinder mission, operations Using an automated machine vision algorithm, the 3d topography of the Martian surface was rapidly recovered fro -a the stereo images captured. by the Tender camera to produce photo-realistic 3d models, An advanced, interface was developed for visualization and interaction with. the virtual environment of the Pathfinder landing site for mission scientists at the Space Flight Operations Facility of the Jet Propulsion Laboratory. The VR aspect of the display allowed mission scientists to navigate on Mars in Bud while remaining here on Earth, thus improving their spatial awareness of the rock field that surrounds the lenders Measurements of positions, distances and angles could be easily extracted from the topographic models, providing valuable information for science analysis and mission. planning. Moreover, the VR map of Mars has also been used to assist with the archiving and planning of activities for the Sojourner rover.

Blackmon, Theodore

1998-01-01

36

The LISA Pathfinder Mission  

NASA Astrophysics Data System (ADS)

LISA Pathfinder (formerly known as SMART-2) is a European Space Agency (ESA) mission designed to pave the way for the joint ESA/NASA Laser Interferometer Space Antenna (LISA) mission by testing in flight the critical technologies required for space-borne gravitational wave detection: it will put two test masses in a near-perfect gravitational free-fall and control and measure their motion with unprecedented accuracy. LISA Pathfinder is currently in the integration and test phase of the development, and is due to be launched on a dedicated launch vehicle in mid 2012, with first results on the performance of the system being available approx 6 months later. This poster will describe the mission in detail, give the current status of the spacecraft devel-opment, and highlight the future milestones in the integration and test campaign.

McNamara, Paul

37

The LISA Pathfinder Mission  

NASA Astrophysics Data System (ADS)

LISA Pathfinder (formerly known as SMART-2) is a European Space Agency (ESA) mission designed to pave the way for the joint ESA/NASA Laser Interferometer Space Antenna (LISA) mission by testing in flight the critical technologies required for space-borne gravitational wave detection: it will put two test masses in a near-perfect gravitational free-fall and control and measure their motion with unprecedented accuracy. LISA Pathfinder is currently in the integration and test phase of the development, and is due to be launched on a dedicated launch vehicle in late 2011, with first results on the performance of the system being available approximately 6 months later. This poster will describe the mission in detail, give the current status of the spacecraft development, and highlight the future milestones in the integration and test campaign.

Stebbins, Robin T.; LISA Pathfinder Science Working Team

2010-01-01

38

A model of the effects of land-based, human activities on the health of coral reefs in the Great Barrier Reef and in Fouha Bay, Guam, Micronesia  

Microsoft Academic Search

A model is proposed to explain coral and algal abundance on coastal coral reefs as a function of spike-like natural disturbances from tropical cyclones and turbid river floods, followed by long recovery periods where the rate of reef recovery depends on ambient water and substratum quality. The model includes competition for space between corals and algae, coral recruitment and reef

Eric Wolanski; Robert H. Richmond; Laurence McCook

2004-01-01

39

Development of ecotoxicology procedures for use in assessing health of coral reefs  

SciTech Connect

There is widespread concern over the apparent worldwide decline in the health of coral reefs. However, assessment methods, other than long-term monitoring, have not yet been attempted. To remedy this the authors are developing ecotoxicology procedures to assess the effects of water quality factors on the corals themselves. Because of the problems of working with large, attached organisms, the authors have concentrated on developing small clonal preparations from corals with both a branching and a massive growth-form. For branching corals, tips (`nubbins`) are removed, and the cut surface ground smooth before cementing to 30mm x 30mm acrylic squares. Cores, or `explants`, 25mm in diameter are removed from massive corals and cemented into injection-moulded plastic cups, to protect the cut surfaces of the skeleton. Trays of up to 18 nubbins and explants may then be transferred to the reef, where they are affixed to previously installed concrete breeze blocks. They may then be retrieved as required to assess the effects of water quality upon them. For laboratory ecotoxicology experiments, the authors have devised a system of artificial lighting, using halide lamps, to grow coral nubbins and explants under controlled conditions. To test the effects of pollutants, the authors use measurements of respiration, photosynthesis and skeletal growth rate. Growth is measured by a very simple buoyant weighing procedure, which requires only an analytical laboratory balance, and an easily-constructed plastic box-shaped chamber. The method is sufficiently sensitive to measure growth over a 24 hour period in some fast-growing corals. The authors will describe the results of initial experiments, carried out at the Bellairs Research Institute, Barbados, on the effects of different levels of phosphate and nitrate in the seawater. For the first time, they are able to demonstrate the concentration-related decrease in growth rate associated with nitrate eutrophication.

Davies, P.S.; Marubini, F. [Univ. of Glasgow (United Kingdom). Division of Environmental and Evolutionary Biology

1995-12-31

40

The Mars Pathfinder Mission  

NASA Technical Reports Server (NTRS)

Mars Pathfinder, one of the first Discovery-class missions (quick, low-cost projects with focused science objectives), will land a single spacecraft with a microrover and several instruments on the surface of Mars in 1997. Pathfinder will be the first mission to use a rover, carrying a chemical analysis instrument, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which will provide a calibration point or "ground truth" for orbital remote sensing observations. In addition to the rover, which also performs a number of technology experiments, Pathfinder carries three science instruments: a stereoscopic imager with spectral filters on an extendable mast, an alpha proton X ray spectrometer, and an atmospheric structure instrument/meteorology package. The instruments, the rover technology experiments, and the telemetry system will allow investigations of the surface morphology and geology at submeter to a hundred meters scale, the petrology and geochemistry of rocks and soils, the magnetic properties of dust, soil mechanics and properties, a variety of atmospheric investigations, and the rotational and orbital dynamics of Mars. Landing downstream from the mouth of a giant catastrophic outflow channel, Ares Vallis at 19.5 deg N, 32.8 deg W, offers the potential of identifying and analyzing a wide variety of crustal materials, from the ancient heavily cratered terrain, intermediate-aged ridged plains, and reworked channel deposits, thus allowing first-order scientific investigations of the early differentiation and evolution of the crust, the development of weathering products, and tile early environments and conditions on Mars.

Golombek, Matthew P.

1997-01-01

41

Spectral discrimination of coral reef bottom types  

Microsoft Academic Search

Degradation of coral reefs is a major environmental problem worldwide. There is a strong management need for cost-effective assessment of environmental health and reef conditions over large regions in remote areas. Remote sensing could be an ideal tool for monitoring coral reefs and related ecosystems in cases where different coral reef substrates are spectrally resolvable. The aim of the present

T. Kutser; W. Skirving; J. Parslow; L. Clementson; T. Done; M. Wakeford; I. Miller

2001-01-01

42

Cytokines Online Pathfinder Encyclopaedia  

NSDL National Science Digital Library

The Cytokines Online Pathfinder Encyclopaedia (COPE) is the brainchild of Horst Ibelgaufts of Germany's Ludwig-Maximilians-Universit't Gene Center. Part super-glossary, part general guide to the "jungles, morasses, and deserts of cytokine-land," this incredibly extensive Web site helps researchers stay on top of newly identified proteins and previously identified but recently reevaluated proteins. As of February 2003, COPE contains over 8,700 entries, which have been mercifully grouped into sub-glossaries by subject: apoptosis, cell lines, chemokines, cytokine topics, hematology, metalloproteinases virokines, viroceptors, and virulence factors.

43

The development of an integrated systems model for balancing coral reef health, land management and tourism risks on the Great Barrier Reef  

Microsoft Academic Search

A prototype Bayesian belief network (BBN) is described that provides catchment-to-reef integration of previously unlinked components of the Great Barrier Reef (GBR) social-ecological system. The BBN is developed to help decision-makers understand the socio-economic trade-offs associated with managing for resilient reef communities given the threat posed by climate change. The probability of severe coral bleaching events increases with climate-driven increases

I. J. Gordon; S. Wooldridge; M. van Grieken; P. Marshall; Barrier Reef

44

Spatial trends in community and health-related characteristics of Galveston Bay oyster reefs  

E-print Network

The spatial trends in the oyster community and healthrelated variables for Galveston Bay oyster reefs indicated that some other factors in addition to salinity are major structuring forces. Three different directional trends were found including one...

Song, Junggeun

1994-01-01

45

Pathfinder Rover Atop Mermaid Dune  

NASA Technical Reports Server (NTRS)

Mars Pathfinder Lander camera image of Sojourner Rover atop the Mermaid 'dune' on Sol 30. Note the dark material excavated by the rover wheels. These, and other excavations brought materials to the surface for examination and allowed estimates of mechanical properties of the deposits.

NOTE: original caption as published in Science Magazine

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

46

Coral Reefs  

NSDL National Science Digital Library

This page offers information on coral reefs. Coral reefs are often refered to as the rainforest of the oceans. This exploration will help you to see why that is. Follow these links to learn about coral reefs. This link will take you to Florida where a girl will take guide you over a coral reef. Coral Kid This site ...

dramsden

2009-11-19

47

Reef ED  

NSDL National Science Digital Library

Great Barrier Reef Marine Park Authority's resource and activity center for teachers and students. Find teaching units for K-12 on: coral reef habitats and marine life; human dependence and impacts on the reef; biodiversity and threatened species; coastal zone and reef management. Lesson plans offer objectives, inquiry learning focus activities, resources, class or field activities. Student pages contain: marine life profiles; reef conservation projects; role playing activities; web investigations. Excellent image library (stills and video).

48

LISA Pathfinder: mission and status  

NASA Astrophysics Data System (ADS)

LISA Pathfinder, the second of the European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology demonstrator for the joint ESA/NASA Laser Interferometer Space Antenna (LISA) mission. The technologies required for LISA are many and extremely challenging. This coupled with the fact that some flight hardware cannot be fully tested on ground due to Earth-induced noise led to the implementation of the LISA Pathfinder mission to test the critical LISA technologies in a flight environment. LISA Pathfinder essentially mimics one arm of the LISA constellation by shrinking the 5 million kilometre armlength down to a few tens of centimetres, giving up the sensitivity to gravitational waves, but keeping the measurement technology: the distance between the two test masses is measured using a laser interferometric technique similar to one aspect of the LISA interferometry system. The scientific objective of the LISA Pathfinder mission consists then of the first in-flight test of low frequency gravitational wave detection metrology. LISA Pathfinder is due to be launched in 2013 on-board a dedicated small launch vehicle (VEGA). After a series of apogee raising manoeuvres using an expendable propulsion module, LISA Pathfinder will enter a transfer orbit towards the first Sun-Earth Lagrange point (L1). After separation from the propulsion module, the LPF spacecraft will be stabilized using the micro-Newton thrusters, entering a 500 000 km by 800 000 km Lissajous orbit around L1. Science results will be available approximately 2 months after launch.

Antonucci, F.; Armano, M.; Audley, H.; Auger, G.; Benedetti, M.; Binetruy, P.; Boatella, C.; Bogenstahl, J.; Bortoluzzi, D.; Bosetti, P.; Caleno, M.; Cavalleri, A.; Cesa, M.; Chmeissani, M.; Ciani, G.; Conchillo, A.; Congedo, G.; Cristofolini, I.; Cruise, M.; Danzmann, K.; De Marchi, F.; Diaz-Aguilo, M.; Diepholz, I.; Dixon, G.; Dolesi, R.; Dunbar, N.; Fauste, J.; Ferraioli, L.; Fertin, D.; Fichter, W.; Fitzsimons, E.; Freschi, M.; García Marin, A.; García Marirrodriga, C.; Gerndt, R.; Gesa, L.; Gilbert, F.; Giardini, D.; Grimani, C.; Grynagier, A.; Guillaume, B.; Guzmán, F.; Harrison, I.; Heinzel, G.; Hewitson, M.; Hollington, D.; Hough, J.; Hoyland, D.; Hueller, M.; Huesler, J.; Jeannin, O.; Jennrich, O.; Jetzer, P.; Johlander, B.; Killow, C.; Llamas, X.; Lloro, I.; Lobo, A.; Maarschalkerweerd, R.; Madden, S.; Mance, D.; Mateos, I.; McNamara, P. W.; Mendes, J.; Mitchell, E.; Monsky, A.; Nicolini, D.; Nicolodi, D.; Nofrarias, M.; Pedersen, F.; Perreur-Lloyd, M.; Perreca, A.; Plagnol, E.; Prat, P.; Racca, G. D.; Rais, B.; Ramos-Castro, J.; Reiche, J.; Romera Perez, J. A.; Robertson, D.; Rozemeijer, H.; Sanjuan, J.; Schleicher, A.; Schulte, M.; Shaul, D.; Stagnaro, L.; Strandmoe, S.; Steier, F.; Sumner, T. J.; Taylor, A.; Texier, D.; Trenkel, C.; Tombolato, D.; Vitale, S.; Wanner, G.; Ward, H.; Waschke, S.; Wass, P.; Weber, W. J.; Zweifel, P.

2011-05-01

49

Mars Pathfinder Landing Site Workshop  

NASA Technical Reports Server (NTRS)

The Mars Pathfinder Project is an approved Discovery-class mission that will place a lander and rover on the surface of the Red Planet in July 1997. The Mars Pathfinder Landing Site Workshop was designed to allow the Mars scientific community to provide input as to where to land Pathfinder on Mars. The workshop was attended by over 60 people from around the United States and from Europe. Over 20 landing sites were proposed at the workshop, and the scientific questions and problems concerning each were addressed. The workshop and the discussion that occured during and afterward have significantly improved the ability to select a scientifically exciting but safe landing site on Mars.

Golombek, Matthew (editor)

1994-01-01

50

Status of coral reef and reef fish resources of Vanuatu  

Microsoft Academic Search

The coral reefs of Vanuatu contribute to rural incomes, nutrition, shoreline protection and, more importantly, self reliance for the people of Vanuatu. The total area of shallow water benthic coral communities is relatively small, approximately 408 square kilometres out of a combined land area of 12, 190 square kilometres. Although there are many reefs of exceptional beauty in good health,

William Naviti; James Aston

51

LISA Pathfinder: mission and status  

Microsoft Academic Search

LISA Pathfinder, the second of the European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology demonstrator for the joint ESA\\/NASA Laser Interferometer Space Antenna (LISA) mission. The technologies required for LISA are many and extremely challenging. This coupled with the fact that some flight hardware cannot be fully tested on ground due to Earth-induced

F. Antonucci; M. Armano; H. Audley; G. Auger; M. Benedetti; P. Binetruy; C. Boatella; J. Bogenstahl; D. Bortoluzzi; P. Bosetti; M. Caleno; A. Cavalleri; M. Cesa; M. Chmeissani; G. Ciani; A. Conchillo; G. Congedo; I. Cristofolini; M. Cruise; K. Danzmann; F. De Marchi; M. Diaz-Aguilo; I. Diepholz; G. Dixon; R. Dolesi; N. Dunbar; J. Fauste; L. Ferraioli; D. Fertin; W. Fichter; E. Fitzsimons; M. Freschi; A. García Marin; C. García Marirrodriga; R. Gerndt; L. Gesa; F. Gilbert; D. Giardini; C. Grimani; A. Grynagier; B. Guillaume; F. Guzmán; I. Harrison; G. Heinzel; M. Hewitson; D. Hollington; J. Hough; D. Hoyland; M. Hueller; J. Huesler; O. Jeannin; O. Jennrich; P. Jetzer; B. Johlander; C. Killow; X. Llamas; I. Lloro; A. Lobo; R. Maarschalkerweerd; S. Madden; D. Mance; I. Mateos; P. W. McNamara; J. Mendes; E. Mitchell; A. Monsky; D. Nicolini; D. Nicolodi; M. Nofrarias; F. Pedersen; M. Perreur-Lloyd; A. Perreca; E. Plagnol; P. Prat; G. D. Racca; B. Rais; J. Ramos-Castro; J. Reiche; J. A. Romera Perez; D. Robertson; H. Rozemeijer; J. Sanjuan; A. Schleicher; M. Schulte; D. Shaul; L. Stagnaro; S. Strandmoe; F. Steier; T. J. Sumner; A. Taylor; D. Texier; C. Trenkel; D. Tombolato; S. Vitale; G. Wanner; H. Ward; S. Waschke; P. Wass; W. J. Weber; P. Zweifel

2011-01-01

52

Pathfinder Teaching and Learning Units.  

ERIC Educational Resources Information Center

This collection of teaching units were selected from materials developed during the Operation Pathfinder Institutes (OPI) which took place in the Pacific region between 1994 and 1999. The institutes were intended to provide upper elementary and middle school science teachers with an opportunity to develop a deeper understanding of the marine…

Hawaii Univ., Honolulu. Sea Grant Program.

53

Metatranscriptome Sequencing of a Reef-building Coral Elucidates Holobiont Community Gene Functions in Health and Disease  

NASA Astrophysics Data System (ADS)

The coral reefs of the Abrolhos Bank of Brazil play a vital ecological role in the health of the Southern Atlantic Ocean, but accelerating rates of disease, particularly white plague, threaten this ecosystem. Thus, an understanding of white plague disease and diagnostic tests for it are urgently needed. The coral animal is associated with a distinct microbiome, a diverse assemblage of eukaryotes, bacteria, and viruses. That these microbes have a great influence on the health of the coral has been long known, however, most of their functions are still mysterious. While recent studies have contrasted healthy and white-plague-associated communities, the causative agents and mechanisms of the disease remain unknown. We collected fragments of healthy and diseased corals, as well as post-disease skeleton, from 12 colonies of the genus Mussismilia, the major component of the reef structure in the Abrolhos bank, and increasingly, a victim of white-plague disease. Fragments were flash-frozen in situ, and prepped for culture-free high throughput sequencing of gene transcripts with the Illumina II-G. While the membership of the microbial communities associated with coral has been previously described, the a coral holobiont community's gene function has, to date, never been assayed by this powerful approach. We designed a bioinformatics pipeline to analyze the short-read data from this complex sample: identifying the functions of genes expressed in the holobiont, and describing the active community's taxonomic composition. We show that gene functions expressed by the coral's bacterial assemblage are distinct from those of the underlying skeleton, and we highlight differences in the disease samples. We find that gene markers for the dissimilatory sulfate reduction pathway more abundant in the disease state, and we further quantify this difference with qPCR. Finally, we report the abundant expression of highly repetitive transcripts in the diseased coral samples, and highlight other coral host genes whose expression differs in this disease. Our work provides a first glimpse into coral holobiont community gene function and its deviations in disease. Moreover, we hope that our bioinformatic protocol, designed to cope with the challenges of short-read transcriptomics from complex ecosystems with no close reference, will be a useful template to further understanding of the gene functions and ecological partnerships in coral reefs and other complex ecosystems.

Timberlake, S.; Helbig, T.; Fernando, S.; Penn, K.; Alm, E.; Thompson, F.; Thompson, J. R.

2012-12-01

54

Spacetime Metrology with LISA Pathfinder  

NASA Astrophysics Data System (ADS)

LISA is the proposed ESA-NASA gravitational wave detector in the 0.1 mHz - 0.1 Hz band. LISA Pathfinder is the down-scaled version of a single LISA arm. The arm - named Doppler link - can be treated as a differential accelerometer, measuring the relative acceleration between test masses. LISA Pathfinder - the in-flight test of the LISA instrumentation - is currently in the final implementation and planned to be launched in 2014. It will set stringent constraints on the ability to put test masses in geodesic motion to within the required differential acceleration of 3times10^{-14} m s^{-2} Hz^{-1/2} and track their relative motion to within the required differential displacement measurement noise of 9times10^{-12} m Hz^{-1/2}, around 1 mHz. Given the scientific objectives, it will carry out - for the first time with such high accuracy required for gravitational wave detection - the science of spacetime metrology, in which the Doppler link between two free-falling test masses measures the curvature. This thesis contains a novel approach to the calculation of the Doppler response to gravitational waves. It shows that the parallel transport of 4-vectors records the history of gravitational wave signals. In practice, the Doppler link is implemented with 4 bodies in LISA and 3 bodies in LISA Pathfinder. To compensate for noise sources a control logic is implemented during the measurement. The closed-loop dynamics of LISA Pathfinder can be condensed into operators acting on the motion coordinates, handling the couplings, as well as the cross-talks. The scope of system identification is the optimal calibration of the instrument. This thesis describes some data analysis procedures applied to synthetic experiments and shows the relevance of system identification for the success of LISA Pathfinder in demonstrating the principles of spacetime metrology for all future space-based missions.

Congedo, Giuseppe

2012-04-01

55

Reef Relief  

NSDL National Science Digital Library

A thorough overview of coral reefs around the globe, including the threats facing them, current protection projects, and action you can take to help save reefs. "International Projects" and "The Coral Reef Ecosystem" sections are chock-full of fantastic photographs and information. Education materials may be purchased and include DVDs and teacher's guides. Many volunteer and donation opportunities. Children section includes information-filled printable coloring pages. Several different publications are available at no cost.

56

Serge Andre foue t Hector M. Guzman Coral reef distribution, status and geomorphologybiodiversity  

E-print Network

REPORT Serge Andre´ foue¨ t � Hector M. Guzman Coral reef distribution, status and geomorphology of the reef geomor- phology and benthic communities of Kuna Yala coral reefs (Caribbean Panama) comes from of coral, octocorals, and sponges) and reef health (coral versus algal cover). For a total reef system

Bermingham, Eldredge

57

Multispectral Imaging from Mars PATHFINDER  

NASA Technical Reports Server (NTRS)

The Imager for Mars Pathfinder (IMP) was a mast-mounted instrument on the Mars Pathfinder lander which landed on Mars Ares Vallis floodplain on July 4, 1997. During the 83 sols of Mars Pathfinders landed operations, the IMP collected over 16,600 images. Multispectral images were collected using twelve narrowband filters at wavelengths between 400 and 1000 nm in the visible and near infrared (VNIR) range. The IMP provided VNIR spectra of the materials surrounding the lander including rocks, bright soils, dark soils, and atmospheric observations. During the primary mission, only a single primary rock spectral class, Gray Rock, was recognized; since then, Black Rock, has been identified. The Black Rock spectra have a stronger absorption at longer wavelengths than do Gray Rock spectra. A number of coated rocks have also been described, the Red and Maroon Rock classes, and perhaps indurated soils in the form of the Pink Rock class. A number of different soil types were also recognized with the primary ones being Bright Red Drift, Dark Soil, Brown Soil, and Disturbed Soil. Examination of spectral parameter plots indicated two trends which were interpreted as representing alteration products formed in at least two different environmental epochs of the Ares Vallis area. Subsequent analysis of the data and comparison with terrestrial analogs have supported the interpretation that the rock coatings provide evidence of earlier martian environments. However, the presence of relatively uncoated examples of the Gray and Black rock classes indicate that relatively unweathered materials can persist on the martian surface.

Ferrand, William H.; Bell, James F., III; Johnson, Jeffrey R.; Bishop, Janice L.; Morris, Richard V.

2007-01-01

58

Region of Pathfinder landing site  

NASA Technical Reports Server (NTRS)

This image, taken by the Viking 1 orbiter in 1976, has been used by scientists to pinpoint the location of the Sagan Memorial Station. The lander is positioned at the center of the blue 'rays,' and North is at the top. The prominent twin hills dubbed 'Twin Peaks' are west of the lander, and the prominent large crater dubbed 'Big Crater' is at center. The small crater at the north border of Big Crater, dubbed 'Rim Shot Crater,' and 'Little Crater' were features that helped scientists accurately identify the location of the lander on the Martian surface and are shown in the two insets. The spacecraft landed successfully within its original target ellipse, which measured 100 km (62 mi) by 200 km (124 mi).

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

1997-01-01

59

Coral Reefs  

NSDL National Science Digital Library

Description of coral reef environment for high school level and higher. Page is chock full of fantastic photographs each featuring a descriptive caption. Topics discussed include ecology, symbiosis, and predator defense. The site features many different species and stages of coral from all over the globe, and also many of the fishes that are associated with coral reefs.

60

Coral Reefs  

NSDL National Science Digital Library

This problem-based learning (PBL) module prompts students to address coral reef destruction and think about biodiversity worldwide. Students identify possible sources of coral reef destruction, examine conflicting evidence, evaluate possible courses of action, and make recommendations. As they do this, students look at man's impact on the global environment. Two versions of the PBL module are provided. The middle school scenario focuses on the question: is the cumulative weight of human activities changing the environment and destroying coral reefs—one of Earth’s last great areas of biodiversity? The high school scenario focuses on the question: what are the pros and cons of artificial reefs—are they effective in preserving biodiversity that can be lost when natural coral reefs are destroyed? This module is part of Exploring the Environment.

61

Which Environmental Factors Predict Seasonal Variation in the Coral Health of Acropora digitifera and Acropora spicifera at Ningaloo Reef?  

PubMed Central

The impact of physico-chemical factors on percent coral cover and coral health was examined on a spatial basis for two dominant Acropora species, A. digitifera and A. spicifera, at Ningaloo Reef (north-western Australia) in the southeast Indian Ocean. Coral health was investigated by measuring metabolic indices (RNA/DNA ratio and protein concentration), energy levels (lipid ratio) and autotrophic indices (chlorophyll a (chl a) and zooxanthellae density) at six stations during typical seasons (austral autumn 2010 (March and April), austral winter 2010 (August)) and during an extreme La Niña event in summer 2011 (February). These indices were correlated with 15 physico-chemical factors (measured immediately following coral sampling) to identify predictors for health indices. Variations in metabolic indices (protein concentration and RNA/DNA ratio) for A. spicifera were mainly explained by nitrogen, temperature and zooplankton concentrations under typical conditions, while for A. digitifera, light as well as phytoplankton, in particular picoeukaryotes, were important, possibly due to higher energy requirement for lipid synthesis and storage in A. digitifera. Optimum metabolic values occurred for both Acropora species at 26–28°C when autotrophic indices (chl a and zooxanthellae density) were lowest. The extreme temperature during the La Niña event resulted in a shift of feeding modes, with an increased importance of water column plankton concentrations for metabolic rates of A. digitifera and light and plankton for A. spicifera. Our results suggest that impacts of high sea surface temperatures during extreme events such as La Niña may be mitigated via reduction on metabolic rates in coral host. The high water column plankton concentrations and associated low light levels resulted in a shift towards high symbiont densities, with lower metabolic rates and energy levels than the seasonal norm for the coral host. PMID:23637770

Hinrichs, Saskia; Patten, Nicole L.; Feng, Ming; Strickland, Daniel; Waite, Anya M.

2013-01-01

62

Which environmental factors predict seasonal variation in the coral health of Acropora digitifera and Acropora spicifera at Ningaloo Reef?  

PubMed

The impact of physico-chemical factors on percent coral cover and coral health was examined on a spatial basis for two dominant Acropora species, A. digitifera and A. spicifera, at Ningaloo Reef (north-western Australia) in the southeast Indian Ocean. Coral health was investigated by measuring metabolic indices (RNA/DNA ratio and protein concentration), energy levels (lipid ratio) and autotrophic indices (chlorophyll a (chl a) and zooxanthellae density) at six stations during typical seasons (austral autumn 2010 (March and April), austral winter 2010 (August)) and during an extreme La Niña event in summer 2011 (February). These indices were correlated with 15 physico-chemical factors (measured immediately following coral sampling) to identify predictors for health indices. Variations in metabolic indices (protein concentration and RNA/DNA ratio) for A. spicifera were mainly explained by nitrogen, temperature and zooplankton concentrations under typical conditions, while for A. digitifera, light as well as phytoplankton, in particular picoeukaryotes, were important, possibly due to higher energy requirement for lipid synthesis and storage in A. digitifera. Optimum metabolic values occurred for both Acropora species at 26-28°C when autotrophic indices (chl a and zooxanthellae density) were lowest. The extreme temperature during the La Niña event resulted in a shift of feeding modes, with an increased importance of water column plankton concentrations for metabolic rates of A. digitifera and light and plankton for A. spicifera. Our results suggest that impacts of high sea surface temperatures during extreme events such as La Niña may be mitigated via reduction on metabolic rates in coral host. The high water column plankton concentrations and associated low light levels resulted in a shift towards high symbiont densities, with lower metabolic rates and energy levels than the seasonal norm for the coral host. PMID:23637770

Hinrichs, Saskia; Patten, Nicole L; Feng, Ming; Strickland, Daniel; Waite, Anya M

2013-01-01

63

Great Barrier Reef  

Atmospheric Science Data Center

article title:  Australia's Great Barrier Reef     View Larger Image ... not a single reef, but a vast maze of reefs, passages, and coral cays (islands that are part of the reef). This nadir true-color image was ...

2013-04-16

64

Software Aids Visualization Of Mars Pathfinder Mission  

NASA Technical Reports Server (NTRS)

Report describes Simulator for Imager for Mars Pathfinder (SIMP) computer program. SIMP generates "virtual reality" display of view through video camera on Mars lander spacecraft of Mars Pathfinder mission, along with display of pertinent textual and graphical data, for use by scientific investigators in planning sequences of activities for mission.

Weidner, Richard J.

1996-01-01

65

Electrostatic disturbances aboard LISA Pathfinder  

NASA Astrophysics Data System (ADS)

Test mass charging and stray electrostatic fields are a potentially important source of force noise for the LISA Pathfinder mission. During the flight we plan to measure the relevant stray electrostatic fields on the surfaces of both the test mass and the electrode housing and compensate them with DC electrode bias voltages. In addition we monitor the charge and reduce it to near zero by UV illumination. We describe the analysis techniques used during the mission and explain the importance of periodic charging/discharging and of long-term charge measurements to limit the force noise at low frequency, which is particularly relevant for the eLISA mission.

Ferroni, Valerio

66

Coral Reefs  

NSDL National Science Digital Library

In this video, Jonathan examines the biology of coral reefs and their importance to the marine ecosystem. Please see the accompanying lesson plan that discusses pH and ocean acidification for educational objectives, discussion points and classroom activities.

Jonathan Bird Productions

2012-03-01

67

Coral Reefs  

NSDL National Science Digital Library

Scientists are studying coral reefs around the world to discover the impact that warmer temperatures and increased carbon dioxide may have on the life cycle of corals. "Changing Planet" is produced in partnership with the National Science Foundation.

NBC Learn

2010-10-07

68

"Library as Laboratory": Online Pathfinders and the Humanities Graduate Student  

ERIC Educational Resources Information Center

This article explores how online pathfinders can best meet the information needs of graduate students and foster advanced research. The article reviews the literature on pathfinders, including the historic characteristics of print pathfinders, and the recommendations that have emerged for online pathfinder content. The article explores the…

Harrington, Sara

2007-01-01

69

Pathfinder aircraft returning from a flight  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered research aircraft settles in for landing on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, after a successful test flight Nov. 19, 1996. The ultra-light craft flew a racetrack pattern at low altitudes over the flight test area for two hours while project engineers checked out various systems and sensors on the uninhabited aircraft. The Pathfinder was controlled by two pilots, one in a mobile control unit which followed the craft, the other in a stationary control station. Pathfinder, developed by AeroVironment, Inc., is one of several designs being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

70

Navigation Flight Operations for Mars Pathfinder  

NASA Technical Reports Server (NTRS)

On July 4, 1997, Mars Pathfinder became the first spacecraft to land on the surface of Mars in 21 years. Pathfinder was launched on December 4, 1996 and spent seven months en route to the red planet. This report discusses the navigation flight experience for the Mars Pathfinder interplanetary cruise. In particular, orbit determination and maneuver design and execution results are presented. Special emphasis is given to the navigation role in the days and hours leading up to and including the Entry, Descent, and Landing (EDL) phase.

Vaughan, Robin M.; Kallemeyn, Pieter H., Jr.; Spencer, David A.; Braun, Robert D.

2004-01-01

71

Community structure and coral status across reef fishing intensity gradients in Palk Bay reef, southeast coast of India.  

PubMed

Coral reef fishes are exploited without the knowledge of their sustainability and their possible effect in altering the community structure of a coral reef ecosystem. Alteration of the community structure could cause a decline in the health of coral reefs and its services. We documented the coral community structure, status of live corals and reef fish assemblages in Palk Bay at the reef fishing hotspots and its nearby reef area with minimum fishing pressure and compared it with a control reef area where reef fishing was banned for more than two decades. The comparison was based on the percent cover of different forms of live corals, their diversity and the density and diversity of reef fishes. The reef fish stock in the reef fishing hotspots and its neighbouring reef was lower by 61 and 38%, respectively compared to the control reef. The herbivore fish Scarus ghobban and Siganus javus were exploited at a rate of 250 and 105 kg month(-1) fishermen(-1), respectively, relatively high comparing the small reef area. Live and dead corals colonized by turf algae were predominant in both the reef fishing hotspots and its nearby coral ecosystems. The percent cover of healthy live corals and live corals colonized by turf algae was <10 and >80%, respectively, in the intensively fished coral ecosystems. The corals were less diverse and the massive Porites and Favia colonies were abundant in the intensive reef fishing sites. Results of this study suggest that the impact of reef fish exploitation was not solely restricted to the intensively fished reefs, but also to the nearby reefs which play a critical role in the resilience of degraded reef ecosystems. PMID:24859909

Manikandan, B; Ravindran, J; Shrinivaasu, S; Marimuthu, N; Paramasivam, K

2014-10-01

72

Mission Operations of LISA Pathfinder  

NASA Astrophysics Data System (ADS)

The mission operations of LISA Pathfinder will focus on extracting the maximum science from the mission. In order to do that, the operational timeline must remain flexible and be able to adapt to new information about the system as it comes in. At the end of the science operations phase, the goal is to have optimised the system to produce the quietest free-fall of the test-masses possible, as well as to have built up a comprehensive noise model of the system to allow robust performance projections of future LISA-like missions. This talk will discuss some of the details of the operational scenarios and talk about the approach to optimising performance and establishing a system noise budget.

Hewitson, Martin

73

Pathfinder-Plus flight in Hawaii  

NASA Technical Reports Server (NTRS)

Pathfinder-Plus flight in Hawaii June 2002 AeroVironment's Pathfinder-Plus solar-powered flying wing recently flew a three-flight demonstration of its ability to relay third-generation cell phone and video signals as well as provide Internet linkage. The two pods underneath the center section of the wing carried the advanced two-way telecom package, developed by Japanese telecommunications interests.

2002-01-01

74

Power and pyro subsystems for Mars Pathfinder  

SciTech Connect

The Power and Pyro Subsystem (PPS) for Mars Pathfinder was designed to support the spacecraft activities during Launch, Cruise, Entry and Landing and Mars operation phases of the mission. The key design constraints were cost, volume and mass. The PPS consists of solar arrays, batteries and power electronics. This paper describes the Mars Pathfinder mission, key requirements on PPS, and PPS system architecture and description of each element of the PPS system.

Shirbacheh, M. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

1997-12-31

75

Coral Reef Ecosystems: Ecosystems in Crisis  

NSDL National Science Digital Library

This Science Object is the fourth of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the natural and human causes of ecosystem stress. Human beings live near coral ecosystems and use them in a variety of ways. Increasing amounts of stress is brought on these ecosystems as humans continue to modify the surrounding environment as a result of population growth, technology, and consumption. Human destruction of habitats through direct harvesting, pollution, atmospheric changes, and other factors is threatening the stability and overall health of many coral reefs. Human activities may also exacerbate the impact of natural disturbances on coral reefs or compromise the ability of the reef to recover from events such as hurricanes, tsunamis, or disease. Learning Outcomes:? Describe ways in which human activities directly impact coral reef ecosystems (resource and recreational uses).? Describe ways in which human activities indirectly impact coral reef ecosystems (by changing the physical conditions, pollution, changes in the water chemistry, etc.).? Explain how human activity may decrease the reefs ability to recover from natural occurrences. ? Explain the effects of increased predation or disease on a reef ecosystem.? Describe the effect of habitat loss on the reef ecosystem.? Describe the effects of weather and climate change on a healthy and weakened reef ecosystem.

National Science Teachers Association (NSTA)

2007-03-28

76

Coral reef assessment: An index utilizing sediment constituents  

Microsoft Academic Search

Resource managers need inexpensive bioindicators to evaluate the health of coral reef ecosystems and to inform decisions on when and where to utilize more expensive assessment techniques. Following USEPA Guidelines for Evaluating Ecological Indicators, I developed the SEDCON Index (SI), a rapid-assessment protocol whichutilizes reef sediment composition to assess the integrity of coral-reef communities. Keyadvantages of this index are that

Camille A. Daniels

2005-01-01

77

SCUBA Diver Specialization and Behavior Norms at Coral Reefs  

Microsoft Academic Search

SCUBA diving is an increasingly popular activity that provides a number of benefits to coastal communities. However, the sustainability of recreational diving on coral reefs is largely dependent on the health of reef ecosystems. Divers can minimize their impacts to coral reefs through responsible diving behaviors, which are in part guided by social norms. The behavioral obligation and sanction components

Laura E. Anderson; David K. Loomis

2011-01-01

78

The Global Coral Reef Crisis: Trends and Solutions (Coral Reefs: Values, Threats, and the Marine Aquarium Trade)  

SciTech Connect

Second only to tropical rainforests, coral reefs support one of the world's most diverse natural habitats. Over 350 million individuals depend on coral reef resources for food and income. Unfortunately, the Earth is in the midst of a coral reef crisis. Anthropogenic impacts including overfishing, destructive fishing practices, sedimentation and pollution, as well as global climate change, have served to disrupt the natural processes that maintain the health of these ecosystems. Until recently, however, the global extent of the coral reef crisis was unknown. Reef Check was developed in 1996 as a volunteer, community-based monitoring protocol designed to measure the health of coral reefs on a global scale. With goals of education, monitoring, and management, Reef Check has activities in over 60 countries and territories. They have not only provided scientific evidence of the global extent of the coral reef crisis, but have provided the first community based steps to alleviate this urgent situation.

Shuman, Craig S. (Reef Check, UCLA) [Reef Check, UCLA

2003-02-05

79

Effectiveness of benthic foraminiferal and coral assemblages as water quality indicators on inshore reefs of the Great Barrier Reef, Australia  

Microsoft Academic Search

Although the debate about coral reef decline focuses on global disturbances (e.g., increasing temperatures and acidification), local stressors (nutrient runoff and overfishing) continue to affect reef health and resilience. The effectiveness of foraminiferal\\u000a and hard-coral assemblages as indicators of changes in water quality was assessed on 27 inshore reefs along the Great Barrier\\u000a Reef. Environmental variables (i.e., several water quality

S. Uthicke; A. Thompson; B. Schaffelke

2010-01-01

80

Jurassic Reef Park  

NSDL National Science Digital Library

Dr. Reinhold Leinfelder of the University of Stuttgart, Germany created this interesting site in English and German, offering a "virtual trip to the reefs of the Jurassic Period." In the Introduction, viewers will find background material and comparisons of modern and ancient reefs. Further information is provided in the sections on reef architecture, reef formation, Jurassic reefs, and reefs and global climate change. Although the English language is slightly quirky, the content and images more than compensate, making this a worthwhile site.

81

LISA Pathfinder Instrument Data Analysis  

NASA Technical Reports Server (NTRS)

LISA Pathfinder (LPF) is an ESA-launched demonstration mission of key technologies required for the joint NASA-ESA gravitational wave observatory in space, LISA. As part of the LPF interferometry investigations, analytic models of noise sources and corresponding noise subtraction techniques have been developed to correct for effects like the coupling of test mass jitter into displacement readout, and fluctuations of the laser frequency or optical pathlength difference. Ground testing of pre-flight hardware of the Optical Metrology subsystem is currently ongoing at the Albert Einstein Institute Hannover. In collaboration with NASA Goddard Space Flight Center, the LPF mission data analysis tool LTPDA is being used to analyze the data product of these tests. Furthermore, the noise subtraction techniques and in-flight experiment runs for noise characterization are being defined as part of the mission experiment master plan. We will present the data analysis outcome of preflight hardware ground tests and possible noise subtraction strategies for in-flight instrument operations.

Guzman, Felipe

2010-01-01

82

NOAA Coral Reef Watch: Decision Support Tools for Coral Reef Managers  

Microsoft Academic Search

A multitude of natural and anthropogenic stressors exert substantial influence on coral reef ecosystems and contribute to bleaching events, slower coral growth, infectious disease outbreaks, and mortality. Satellite-based observations can monitor, at a global scale, environmental conditions that influence both short-term and long-term coral reef ecosystem health. From research to operations, NOAA Coral Reef Watch (CRW) incorporates paleoclimatic, in situ,

J. Rauenzahn; C. Eakin; W. J. Skirving; T. Burgess; T. Christensen; S. F. Heron; J. Li; G. Liu; J. Morgan; C. Nim; B. A. Parker; A. E. Strong

2010-01-01

83

Mars Pathfinder Atmospheric Entry Navigation Operations  

NASA Technical Reports Server (NTRS)

On July 4, 1997, after traveling close to 500 million km, the Pathfinder spacecraft successfully completed entry, descent, and landing, coming to rest on the surface of Mars just 27 km from its target point. In the present paper, the atmospheric entry and approach navigation activities required in support of this mission are discussed. In particular, the flight software parameter update and landing site prediction analyses performed by the Pathfinder operations navigation team are described. A suite of simulation tools developed during Pathfinder's design cycle, but extendible to Pathfinder operations, are also presented. Data regarding the accuracy of the primary parachute deployment algorithm is extracted from the Pathfinder flight data, demonstrating that this algorithm performed as predicted. The increased probability of mission success through the software parameter update process is discussed. This paper also demonstrates the importance of modeling atmospheric flight uncertainties in the estimation of an accurate landing site. With these atmospheric effects included, the final landed ellipse prediction differs from the post-flight determined landing site by less then 0.5 km in downtrack.

Braun, R. D.; Spencer, D. A.; Kallemeyn, P. H.; Vaughan, R. M.

1997-01-01

84

Project O.R.B (Operation Reef Ball): Creating Artificial Reefs, Educating the Community  

NASA Astrophysics Data System (ADS)

The Project O.R.B. (Operation Reef Ball) team at South Plantation High School's Everglades Restoration & Environmental Science Magnet Program is trying to help our ailing south Florida coral reefs by constructing, deploying, and monitoring designed artificial reefs. Students partnered with the Reef Ball Foundation, local concrete companies, state parks, Girl Scouts, Sea Scouts, local universities and environmental agencies to construct concrete reef balls, each weighing approximately 500 lbs (227 kg). Students then deployed two artificial reefs consisting of over 30 concrete reef balls in two sites previously permitted for artificial reef deployment. One artificial reef was placed approximately 1.5 miles (2.4 km) offshore of Golden Beach in Miami-Dade County with the assistance of Florida Atlantic University and their research vessel. A twin reef was deployed at the mouth of the river in Oleta River State Park in Miami. Monitoring and maintenance of the sites is ongoing with semi-annual reports due to the Reef Ball Foundation and DERM (Department of Environmental Resource Management) of Miami-Dade County. A second goal of Project O.R.B. is aligned with the Florida Local Action Strategy, the Southeast Florida Coral Reef Initiative, and the U.S. Coral Reef Task Force, all of which point out the importance of awareness and education as key components to the health of our coral reefs. Project O.R.B. team members developed and published an activity book targeting elementary school students. Outreach events incorporate cascade learning where high school students teach elementary and middle school students about various aspects of coral reefs through interactive "edu-tainment" modules. Attendees learn about water sampling, salinity, beach erosion, surface runoff, water cycle, ocean zones, anatomy of coral, human impact on corals, and characteristics of a well-designed artificial reef. Middle school students snorkel on the artificial reef to witness first-hand the success of this artificial reef. Over 3,000 students have been reached through the educational outreach endeavors of Project O.R.B. This successful STEM project models the benefits of partnerships with universities, local K-12 public schools and community conservation organizations and provides students with authentic learning experiences. Students are able to have a positive impact on their local coral reef environment, their peers and their community through this comprehensive service-learning project.

Phipps, A.

2012-04-01

85

Web Reef Advisory System  

NSDL National Science Digital Library

The Web Reef Advisory System (WRAS) was developed by ReefBase and Reef Check, in collaboration with the Coastal Resources Center at the University of Rhode Island and the Department of Biological Sciences at the University of Southern California, as "an online application to input, view, and analyse Reef Check survey data. It calculates indicators of how good or bad a shape a particular reef is in, and what the underlying causes may be, based on Reef Check surveys." WRAS allows users to view, analyze, and add (registration required) data. Please note that site users must complete a free and brief registration process before they are granted full access to the Reef Check website. Other site offerings include an interactive Reef Check GIS feature (see website for browser requirements), and The Reef Check Barometer of Global Reef Condition which provides assessments of different regions based on Reef Check Indicators.

86

Mapping Oyster Reef Habitats in Mobile Bay  

NASA Technical Reports Server (NTRS)

Oyster reefs around the world are declining rapidly, and although they haven t received as much attention as coral reefs, they are just as important to their local ecosystems and economies. Oyster reefs provide habitats for many species of fish, invertebrates, and crustaceans, as well as the next generations of oysters. Oysters are also harvested from many of these reefs and are an important segment of many local economies, including that of Mobile Bay, where oysters rank in the top five commercial marine species both by landed weight and by dollar value. Although the remaining Mobile Bay oyster reefs are some of the least degraded in the world, projected climate change could have dramatic effects on the health of these important ecosystems. The viability of oyster reefs depends on water depth and temperature, appropriate pH and salinity levels, and the amount of dissolved oxygen in the water. Projected increases in sea level, changes in precipitation and runoff patterns, and changes in pH resulting from increases in the amount of carbon dioxide dissolved in the oceans could all affect the viability of oyster reefs in the future. Human activities such as dredging and unsustainable harvesting practices are also adversely impacting the oyster reefs. Fortunately, several projects are already under way to help rebuild or support existing or previously existing oyster reefs. The success of these projects will depend on the local effects of climate change on the current and potential habitats and man s ability to recognize and halt unsustainable harvesting practices. As the extent and health of the reefs changes, it will have impacts on the Mobile Bay ecosystem and economy, changing the resources available to the people who live there and to the rest of the country, since Mobile Bay is an important national source of seafood. This project identified potential climate change impacts on the oyster reefs of Mobile Bay, including the possible addition of newly viable habitats in the southeastern regions of the Bay.

Bolte, Danielle

2011-01-01

87

Overhead view of Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

This image, prepared by Pathfinder scientists at NASA/ Ames Research Center, is a view of the landing site from above. Seen in the lower right is Mermaid dune, with its long axis oriented northwest-southeast and its steeper side, the presumed slipface, toward the southwest. Dunes like Mermaid, the depositional tails and erosional moats associated with rocks in the area, and the fluted and polished surfaces on several boulders at the landing site all indicate an effective wind that blows from the northeast to the southwest.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

88

Dynamic Pathfinders: Leveraging Your OPAC to Create Resource Guides  

ERIC Educational Resources Information Center

Library pathfinders are a time-tested method of leading library users to important resources. However, paper-based pathfinders suffer from space limitations, and both paper-based and Web-based pathfinders require frequent updates to keep up with new library acquisitions. This article details a step-by-step method to create an online dynamic…

Hunter, Ben

2008-01-01

89

Mars Pathfinder Mission Telescopic Observational Support  

NASA Astrophysics Data System (ADS)

Monitoring of the martian atmosphere by professional and amateur astronomers during the 1997 opposition is important for the Mars Pathfinder project because the entry, descent, and landing (EDL) sequence can be fine-tuned based on updated knowledge of the opacity and density structure of the atmosphere. The atmospheric models that have been used to develop Pathfinder EDL and surface scenarios are based on Viking Lander data, but it has been recognized that the martian atmosphere has recently been significantly colder and clearer than during the Viking missions. On the martian surface, lander and rover power depend on the insolation at the surface and radiative transfer in the atmosphere. Power is needed both to keep electronics warm during the cold martian night and for telecommunications. Hence, the amount of data that can be returned to Earth, and therefore operational scenarios, will depend on the temperature and amount of dust in the martian atmosphere. In addition, observations of Mars during Pathfinder surface operations with the landing site near the sub-Earth point would allow Pathfinder observations to be placed in a global context. Conversely, Pathfinder data will be useful in calibrating telescopic observations of Martian atmospheric opacity and temperatures. Observing time has been allocated for microwave observations of Mars from Kitt Peak and WF/PC2 imaging from the Hubble Space Telescope during the Pathfinder mission. Planning is also underway among amateur astronomers worldwide: for more information, see the MarsWatch home pages at the following URLs: http://mpfwww.jpl.nasa.gov/mpf/marswatch.html http://astrosun.tn.cornell.edu/marsnet/mnhome.html

Herkenhoff, K. E.; Golombek, M. P.; Anderson, R. C.; Bell, J. F., III

1996-09-01

90

Reef Education Network  

NSDL National Science Digital Library

The University of Queensland's Reef Education Network (REN) is a wonderful introduction to the amazing world of coral reefs. REN has some cool images as well as information about reef research, current problems threatening coral reefs, and the many fascinating organisms that reside within a coral reef. The Life And Times section provides a nice overview of what a reef is, while the Ask A Brain Coral section gives some introduction to biotic and abiotic relationships that occur within reefs. A unique feature is the notebook, where students can record and organize information as they navigate throughout the site.

91

NOAA's Coral Reef  

NSDL National Science Digital Library

Portal to NOAA programs on coral reef research, management, protection. Online booklet describes corals, importance of reefs as habitat, value to humans, natural and human impacts. Site offers outreach and online educational materials, including lesson plans and list of things you can do. Search coral reef data and publications, find funding opportunities, review state of U.S. reefs, local and national action plans. Provides links to related sites, including coral reef photo library, international initiatives.

92

Free-Flight Experiments in LISA Pathfinder  

NASA Technical Reports Server (NTRS)

The LISA Pathfinder mission will demonstrate the technology of drag-free test masses for use as inertial references in future space-based gravitational wave detectors. To accomplish this, the Pathfinder spacecraft will perform drag-free flight about a test mass while measuring the acceleration of this primary test mass relative to a second reference test mass. Because the reference test mass is contained within the same spacecraft, it is necessary to apply forces on it to maintain its position and attitude relative to the spacecraft. These forces are a potential source of acceleration noise in the LISA Pathfinder system that are not present in the full LISA configuration. While LISA Pathfinder has been designed to meet it's primary mission requirements in the presence of this noise, recent estimates suggest that the on-orbit performance may be limited by this 'suspension noise'. The drift-mode or free-flight experiments provide an opportunity to mitigate this noise source and further characterize the underlying disturbances that are of interest to the designers of LISA-like instruments. This article provides a high-level overview of these experiments and the methods under development to analyze the resulting data.

Thorpe, J. I.; Cutler, C. J.; Hewitson, M.; Jennrich, O.; Maghami, P.; Paczkowski, S.; Russano, G.; Vitale, S.; Weber, W. J.

2014-01-01

93

Mars Pathfinder Project: Planetary Constants and Models  

NASA Technical Reports Server (NTRS)

This document provides a common set of astrodynamic constants and planetary models for use by the Mars pathfinder Project. It attempts to collect in a single reference all the quantities and models in use across the project during development and for mission operations.

Lyons, D.; Vaughn, R.

1999-01-01

94

Free-flight experiments in LISA Pathfinder  

E-print Network

The LISA Pathfinder mission will demonstrate the technology of drag-free test masses for use as inertial references in future space-based gravitational wave detectors. To accomplish this, the Pathfinder spacecraft will perform drag-free flight about a test mass while measuring the acceleration of this primary test mass relative to a second reference test mass. Because the reference test mass is contained within the same spacecraft, it is necessary to apply forces on it to maintain its position and attitude relative to the spacecraft. These forces are a potential source of acceleration noise in the LISA Pathfinder system that are not present in the full LISA configuration. While LISA Pathfinder has been designed to meet it's primary mission requirements in the presence of this noise, recent estimates suggest that the on-orbit performance may be limited by this `suspension noise'. The drift-mode or free-flight experiments provide an opportunity to mitigate this noise source and further characterize the underlying disturbances that are of interest to the designers of LISA-like instruments. This article provides a high-level overview of these experiments and the methods under development to analyze the resulting data.

M. Armano; H. Audley; G. Auger; J. Baird; P. Binetruy; M. Born; D. Bortoluzzi; N. Brandt; A. Bursi; M. Caleno; A. Cavalleri; A. Cesarini; M. Cruise; C. Cutler; K. Danzmann; I. Diepholz; R. Dolesi; N. Dunbar; L. Ferraioli; V. Ferroni; E. Fitzsimons; M. Freschi; J. Gallegos; C. Garcia. Marirrodriga; R. Gerndt; LI. Gesa; F. Gibert; D. Giardini; R. Giusteri; C. Grimani; I. Harrison; G. Heinzel; M. Hewitson; D. Hollington; M. Hueller; J. Huesler; H. Inchauspe; O. Jennrich; P. Jetzer; B. Johlander; N. Karnesis; B. Kaune; N. Korsakova; C. Killow; I. Lloro; R. Maarschalkerweerd; S. Madden; P. Maghami; D. Mance; V. Martin; F. Martin-Porqueras; I. Mateos; P. McNamara; J. Mendes; L. Mendes; A. Moroni; M. Nofrarias; S. Paczkowski; M. Perreur-Lloyd; A. Petiteau; P. Pivato; E. Plagnol; P. Prat; U. Ragnit; J. Ramos-Castro; J. Reiche; J. A. Romera. Perez; D. Robertson; H. Rozemeijer; G. Russano; P. Sarra; A. Schleicher; J. Slutsky; C. F. Sopuerta; T. Sumner; D. Texier; J. Thorpe; C. Trenkel; H. B. Tu; D. Vetrugno; S. Vitale; G. Wanner; H. Ward; S. Waschke; P. Wass; D. Wealthy; S. Wen; W. Weber; A. Wittchen; C. Zanoni; T. Ziegler; P. Zweifel

2014-12-29

95

Mars Pathfinder, Science Results, Geology and Geomorphology  

NSDL National Science Digital Library

This NASA-hosted site is a section of the Mars Pathfinder Science Results Directory with a specific emphasis on the geologic and geomorphic characteristics observed. Many photos and satellite images are available, with the option to view and download full size images. Scientific theories are offered as to the probable geomorphic agents sculpting Mars' surface.

96

Strategy for selecting Mars Pathfinder landing sites  

NASA Technical Reports Server (NTRS)

A strategy for Pathfinder site selection must be developed that is fundamentally different from most previous considerations. At least two approaches can be identified. In one approach, the objective is to select a site representing a key geologic unit on Mars, i.e., a unit that is widespread, easily recognized, and used frequently as a datum in various investigations. The second approach is to select a site that potentially affords access to a wide variety of rock types. Because rover range is limited, rocks from a variety of sources must be assembled in a small area for sampling. Regardless of the approach taken in site selection, the Pathfinder site should include eolian deposits and provisions should be made to obtain measurements on soils. A recommended approach for selecting the Mars Pathfinder landing site is to identify a deltaic deposit, composed of sediments derived from sources of various ages and geologic units that shows evidence of eolian activity. The site should be located as close as possible to the part of the outwash where rapid deposition occurred because the likelihood of 'sorting' by size and composition increases with distance, decreasing the probability of heterogeneity. In addition, it is recommended that field operation tests be conducted to gain experience and insight into conducting science with Pathfinder.

Greeley, Ronald; Kuzmin, Ruslin O.

1994-01-01

97

Pathfinders on Black Dance in America.  

ERIC Educational Resources Information Center

This is a compilation of 18 pathfinders (i.e., a bibliographic instruction aid) on black dance in America, prepared by graduate students in the "Information Resources in the Humanities" and the "Information Resources in the Social Sciences" classes in the Graduate School of Library and Information Science at the University of Texas at Austin. The…

Roy, Loriene, Ed.

98

Spatial variability of the biogeochemical composition of surface sediments in an insular coral reef ecosystem: Moorea, French Polynesia  

Microsoft Academic Search

The spatial variability of the biogeochemical composition of surface sediments was investigated around Moorea, French Polynesia. This study complements other ones conducted in Moorea to assess coral reef “health”. A total of 35 stations were sampled at four sites around the island, on the following geomorphological units: fringing reef of the bays, fringing reef of the lagoon, channel, barrier reef,

M. Schrimm; R. Buscail; M. Adjeroud

2004-01-01

99

ssential to human well-being, healthy coral reefs are some of the most valuable ecosystems on the  

E-print Network

-based management can preserve, sustain, and restore valuable coral reef ecosystems for future generations. Making managers, CRCP works to protect and restore coral reefs, including deep-water corals, by addressing provides coral reef managers, scientists, and other users worldwide with information about reef health

100

The role of SCUBA diver user fees as a source of sustainable funding for coral reef marine Protected areas  

Microsoft Academic Search

Coral reefs are both highly diverse and economically important. Human activities, however, threaten the world's coral reefs, endangering their biological and economic value. No take Marine Protected Areas (MPA), which ban fishing within MPA boundaries, help conserve and restore reef health and provide ecological resilience to reefs in the face of global warming and ocean acidification. In many cases, cost-benefit

Elizabeth Terk; Nancy Knowlton

2010-01-01

101

Author's personal copy Coral Reefs  

E-print Network

Author's personal copy Coral Reefs D E Burkepile and M E Hay, Georgia Institute of Technology Ecological Interactions on Coral Reefs Replenishment of Coral Reefs: The Role of Reproduction and Recruitment in the Ecology of Reefs Landscape Ecology of Coral Reefs: Connections of Coral Reefs to Mangrove and Seagrass

Burkepile, Deron

102

Assessment of Mars Pathfinder landing site predictions  

USGS Publications Warehouse

Remote sensing data at scales of kilometers and an Earth analog were used to accurately predict the characteristics of the Mars Pathfinder landing site at a scale of meters. The surface surrounding the Mars Pathfinder lander in Ares Vallis appears consistent with orbital interpretations, namely, that it would be a rocky plain composed of materials deposited by catastrophic floods. The surface and observed maximum clast size appears similar to predictions based on an analogous surface of the Ephrata Fan in the Channeled Scabland of Washington state. The elevation of the site measured by relatively small footprint delay-Doppler radar is within 100 m of that determined by two-way ranging and Doppler tracking of the spacecraft. The nearly equal elevations of the Mars Pathfinder and Viking Lander 1 sites allowed a prediction of the atmospheric conditions with altitude (pressure, temperature, and winds) that were well within the entry, descent, and landing design margins. High-resolution (~38 m/pixel) Viking Orbiter 1 images showed a sparsely cratered surface with small knobs with relatively low slopes, consistent with observations of these features from the lander. Measured rock abundance is within 10% of that expected from Viking orbiter thermal observations and models. The fractional area covered by large, potentially hazardous rocks observed is similar to that estimated from model rock distributions based on data from the Viking landing sites, Earth analog sites, and total rock abundance. The bulk and fine-component thermal inertias measured from orbit are similar to those calculated from the observed rock size-frequency distribution. A simple radar echo model based on the reflectivity of the soil (estimated from its bulk density), and the measured fraction of area covered by rocks was used to approximate the quasi-specular and diffuse components of the Earth-based radar echos. Color and albedo orbiter data were used to predict the relatively dust free or unweathered surface around the Pathfinder lander compared to the Viking landing sites. Comparisons with the experiences of selecting the Viking landing sites demonstrate the enormous benefit the Viking data and its analyses and models had on the successful predictions of the Pathfinder site. The Pathfinder experience demonstrates that, in certain locations, geologic processes observed in orbiter data can be used to infer surface characteristics where those processes dominate over other processes affecting the Martian surface layer. Copyright 1999 by the American Geophysical Union.

Golombek, M.P.; Moore, H.J.; Haldemann, A.F.C.; Parker, T.J.; Schofield, J.T.

1999-01-01

103

Life and death on the coral reef: an ecological perspective on scholarly publishing in the health sciences*†  

PubMed Central

Objective: Reflecting patterns evident in past Janet Doe lectures, the 2004 address draws on the foundations of biology to provide a model that offers insights into the advent of electronic publications and choices for the future. Setting: The lecture sketches a picture of the fragile relationships found in complex ecosystems and illustrates how such interdependencies function in the environment of the coral reef. Analysis: Deriving lessons from the marine world, the lecture then shifts to a description of similarities in the realm of scholarly publishing, the impact of digital innovations in the marketplace, and the controversies and choices inherent in open access publications. Conclusions: Lessons from ecology and publishing lead to the conclusion that librarians must take action and risks in this time of dramatic environmental change. PMID:15685268

Forsman, Rick B.

2005-01-01

104

Coral Reef Ecosystems: The Living Reef  

NSDL National Science Digital Library

This Science Object is the first of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the unique and diverse ecosystem of the coral reef. Coral reefs are very complex systems that create one of the largest structures on Earth of biological origins. Thousands of coral species exist in oceans worldwide. Reef-building corals remain on the same spot of the sea floor through their entire lives and have developed reproductive, feeding, and social behaviors suited to their situation. As they grow, reefs provide structural habitats for hundreds to thousands of different organisms. Learning Outcomes:? Identify coral polyp structures and describe their functions.? Describe photosynthesis in the coral environment.? Describe the evolution of a typical reef system.? Use the shape of an individual coral to identify its common name, and classify entire coral reef ecosystems based on shape and location. ? Describe the process of coral polyp reproduction and growth.? Identify how the features and/or behavioral strategies of coral reef inhabitants enable them to survive in coral reef environments.

National Science Teachers Association (NSTA)

2006-11-01

105

Optical payload for the STARE pathfinder mission  

NASA Astrophysics Data System (ADS)

The Space-based Telescopes for Actionable Refinement of Ephemeris (STARE) program will collect the information needed to help satellite operators avoid collisions in space by using a network of nano-satellites to determine more accurate trajectories for selected space objects orbiting the Earth. In the first phase of the STARE program, two pathfinder cube-satellites (CubeSats) equipped with an optical imaging payload are being developed and deployed to demonstrate the main elements of the STARE concept. In this paper, we first give an overview of the STARE program. We then describe the details of the optical imaging payload for the STARE pathfinder CubeSats, including the optical design and the sensor characterization. Finally, we discuss the track detection algorithm that will be used on the images acquired by the payload.

Simms, Lance M.; Riot, Vincent; De Vries, Willem; Olivier, Scot S.; Pertica, Alex; Bauman, Brian J.; Phillion, Don; Nikolaev, Sergei

2011-06-01

106

Disk Galaxies in the Magneticum Pathfinder Simulations  

NASA Astrophysics Data System (ADS)

We present Magneticum Pathfinder, a new set of hydrodynamical cosmological simulations covering a large range of cosmological scales. Among the important physical processes included in the simulations are the chemical and thermodynamical evolution of the diffuse gas as well as the evolution of stars and black holes and the corresponding feedback channels. In the high resolution boxes aimed at studies of galaxy formation and evolution, populations of both disk and spheroidal galaxies are self-consistently reproduced. These galaxy populations match the observed stellar mass function and show the same trends for disks and spheroids in the mass-size relation as observations from the SDSS. Additionally, we demonstrate that the simulated galaxies successfully reproduce the observed specific angular-momentum-mass relations for the two different morphological types of galaxies. In summary, the Magneticum Pathfinder simulations are a valuable tool for studying the assembly of cosmic and galactic structures in the universe.

Remus, Rhea-Silvia; Dolag, Klaus; Bachmann, Lisa K.; Beck, Alexander M.; Burkert, Andreas; Hirschmann, Michaela; Teklu, Adelheid

2015-02-01

107

Potential landing sites for Mars Pathfinder  

NASA Technical Reports Server (NTRS)

In addition to a better understanding of the geological evolution of Mars, new techniques for processing available data have emerged, new data have been acquired, and the engineering approaches for placing spacecraft on the surface have evolved. Selection of the Mars Pathfinder landing site must take these issues into account, along with mission constraints. An advantage of Mars Pathfinder is the rover for sampling surface materials over a range of tens of meters. However, engineering constraints and the limited scientific payload of this mission require new approaches for landing site selection. One approach is to select sites exhibiting a wide variety of rocks near the lander. An alternative approach is to select sites in which the regional geology consists of a single rock type representing a key datum for the geological study of Mars, and is uniformly distributed within the landing ellipse.

Kuzmin, Ruslan O.; Landheim, R.; Greeley, Ronald

1994-01-01

108

Journey to the Reef  

NSDL National Science Digital Library

Despite their experiences with a cartoon sponge, most elementary students know little about the diverse inhabitants of coral reefs. Therefore, with vivid photography and video, diverse coral reef inhabitants were brought to life for the author's fifth-gra

Linda Bryson

2010-01-01

109

Pathfinder-Plus aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder-Plus solar-powered aircraft is shown taking off from a runway, then flying at low altitude over the ocean. The vehicle, which looks like a flying ruler, operates at low airspeed. Among the missions proposed for a solar-powered aircraft are communications relay, atmospheric studies, pipeline monitoring and gas leak detection, environmental monitoring using thermal and radar images, and disaster relief and monitoring.

1998-01-01

110

Mars Pathfinder Project: Planetary Constants and Models  

NASA Technical Reports Server (NTRS)

This document provides a common set of astrodynamic constants and planetary models for use by the Mars Pathfinder Project. It attempts to collect in a single reference all the quantities and models in use across the project during development and for mission operations. These models are central to the navigation and mission design functions, but they are also used in other aspects of the project such as science observation planning and data reduction.

Vaughan, Robin

1995-01-01

111

Journey to the Reef  

ERIC Educational Resources Information Center

Despite their experiences with a cartoon sponge, most elementary students know little about the diverse inhabitants of coral reefs. Therefore, with vivid photography and video, diverse coral reef inhabitants were brought to life for the author's fifth-grade students. Students shared their knowledge in language arts and even explored coral reefs in…

Bryson, Linda

2010-01-01

112

Planetary Coral Reef Foundation  

NSDL National Science Digital Library

The Planetary Coral Reef Foundation was founded in 1991 to address the growing crisis of destruction of coral reefs. Topics include the PCRF's mission, its research activities at sea and in space, wastewater recycling, conservation tips that can help preserve reefs, and the organization's ship, R.V. Heraclitus.

113

Great Barrier Reef  

NSDL National Science Digital Library

This Landsat-7 color composite image shows a section of the famous Great Barrier Reef, the world's largest living organism. This view displays the southern end of the reef where it is composed of smaller, individual reef structures as opposed to a continuous bank as in the north.

NASA

114

Coral Reef Adventure  

NSDL National Science Digital Library

This site from MacGillivray Freeman Films presents information about the movie "Coral Reef Adventure," as well as an assortment of links about coral reefs. In particular, the section on Learning About Reefs features a virtual dive that highlights marine life at various depths. This section also provides educational resources including a teacher's guide and learning activities. The site also includes links to many organizations that provide support for reversing the current worldwide decline in coral reef ecosystems and to finding new and sustainable solutions for managing the world's coral reefs.

MacGillivray Freeman

115

NOAA Coral Reef Watch Calcification Index of Coral Reef Ecosystems  

E-print Network

in the management, study and assessment of impacts of environmental change on coral reef ecosystems. #12;ValueNOAA Coral Reef Watch Calcification Index of Coral Reef Ecosystems NOAANOAA''ss Coral Reef Watch:Coral) NOAA/NESDIS/STAR/SO and Coral Reef Conservation Program (CRCP) NOAA Coral Matrix Silver Spring

Kuligowski, Bob

116

Dioramas: Andros Coral Reef  

NSDL National Science Digital Library

In the shallow waters off the coast of Andros Island in the Caribbean, corals of all shapes and sizes form the Andros Reef, one of the largest barrier reefs in the world. Like other coral reefs, Andros was created by massive colonies of coral polyps, which are small, soft-bodied animals. These creatures have hard skeletons that form much of the structure of a coral reef. The once thriving Andros Reef is now threatened. In the past, antler-shaped elkhorn coral dominated the reef, with multiple colonies extending continuously for long stretches. Throughout the Caribbean today, this species exists primarily in isolated colonies and scientists estimate that in certain places, up to 95 percent of elkhorn coral has died. This site describes the formation of the reef along with the present problems.

117

Coral fluorescence and symbiosis : photoacclimation, thermal shock, life history changes, and implications for reef monitoring  

E-print Network

of the conservation and management of coral reef ecosystems.coral colony size distributions on Kenyan reefs under different managementcoral reefs, understanding the coral symbiosis physiology and having nondestructive tools to monitor coral health will be critical for the conservation and management

Roth, Melissa Susan

2010-01-01

118

Pathfinder: an online collaboration environment for citizen scientists  

Microsoft Academic Search

For over a century, citizen scientists have volunteered to collect huge quantities of data for professional scientists to analyze. We designed Pathfinder, an online environment that challenges this traditional division of labor by providing tools for citizen scientists to collaboratively discuss and analyze the data they collect. We evaluated Pathfinder in a sustainability and commuting context using a mixed methods

Kurt Luther; Scott Counts; Kristin B. Stecher; Aaron Hoff; Paul Johns

2009-01-01

119

Pre-flight development of the PoGOLite Pathfinder  

E-print Network

Pre-flight development of the PoGOLite Pathfinder M´OZSI KISS Doctoral Thesis in Physics Stockholm, Sweden 2011 #12;#12;Doctoral Thesis in Physics Pre-flight development of the PoGOLite Pathfinder M uniformity. Suitable operating parameters for flight, such as threshold settings and PMT voltages, have also

Haviland, David

120

Primary Foreign Language Pathfinders: The Brighton and Hove Experience  

ERIC Educational Resources Information Center

This article reports on a two-year project located within one local authority (LA), Brighton and Hove City Council, which was selected in 2003 to become a Primary Foreign Language Pathfinder. The main aim of this Pathfinder was to work with 18 other LAs across the country to pilot fresh approaches towards delivering foreign languages in the…

Enever, Janet; Watts, Catherine

2009-01-01

121

Mars Pathfinder Wheel Abrasion Experiment Ground Test  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) sent a mission to the martian surface, called Mars Pathfinder. The mission payload consisted of a lander and a rover. The primary purpose of the mission was demonstrating a novel entry, descent, and landing method that included a heat shield, a parachute, rockets, and a cocoon of giant air bags. Once on the surface, the spacecraft returned temperature measurements near the Martian surface, atmosphere pressure, wind speed measurements, and images from the lander and rover. The rover obtained 16 elemental measurements of rocks and soils, performed soil-mechanics, atmospheric sedimentation measurements, and soil abrasiveness measurements.

Keith, Theo G., Jr.; Siebert, Mark W.

1998-01-01

122

Coral Reef Ecosystems  

NSDL National Science Digital Library

The Coral Reef Ecosystems SciPack explores the unique and diverse ecosystem of the coral reef. The focus is on Standards and Benchmarks related to populations and ecosystems using coral reefs and their immediate environment as an example. Because the Standards and Benchmarks present the concepts of populations and ecosystems generically, without reference to a specific ecosystem or the organisms in the system, coral reefs are used to provide the context through which concepts in a marine ecosystem are explored.In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components:? Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. ? Access to one-on-one support via e-mail to content "Wizards".? Final Assessment which can be used to certify mastery of the concepts.Learning Outcomes:Coral Reef Ecosystems: The Living Reef? Identify coral polyp structures and describe their functions.? Describe photosynthesis in the coral environment.? Describe the evolution of a typical reef system.? Use the shape of an individual coral to identify its common name, and classify entire coral reef ecosystems based on shape and location. ? Describe the process of coral polyp reproduction and growth.? Identify how the features and/or behavioral strategies of coral reef inhabitants enable them to survive in coral reef environments.Coral Reef Ecosystems: The Abiotic Setting? Identify the characteristics of an ecosystem, and describe the interdependence between biotic and abiotic features in an ecosystem.? Describe how the following abiotic factors provide coral with the energy needed to survive and grow within their ecosystem: sunlight, water, oxygen, and carbon dioxide.? Describe the optimal environmental conditions for coral reef growth, and explain the process of coral reef development (including the role of available sunlight and calcium).? Explain how the following environmental factors might affect coral ecosystems: increase in dissolved CO2, changes in global temperatures, increase in ocean water turbidity through water pollution.Coral Reef Ecosystems: Interdependence? Identify and label key components of food chains and food webs in a coral reef ecosystem.? Describe key relationships among plants and animals in the coral reef ecosystem: predator and prey relationships, producer and consumer relationships, and symbiotic relationships (mutualism, commensalisms, parasitism).? Recognize the direction that energy travels through food chains and food webs.? Explain that materials (chemical elements) and natural resources are recycled in coral reef ecosystems and reappear in different forms.? Describe the primary ecological succession events within a typical coral reef ecosystem.Coral Reef Ecosystems: Ecosystems in Crisis? Describe ways in which human activities directly impact coral reef ecosystems (resource and recreational uses).? Describe ways in which human activities indirectly impact coral reef ecosystems (by changing the physical conditions, pollution, changes in the water chemistry, etc.).? Explain how human activity may decrease the reefs ability to recover from natural occurrences. ? Explain the effects of increased predation or disease on a reef ecosystem.? Describe the effect of habitat loss on the reef ecosystem.? Describe the effects of weather and climate change on a healthy and weakened reef ecosystem.

National Science Teachers Association (NSTA)

2007-03-28

123

Pathfinder aircraft taking off - setting new solar powered altitude record  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered remotely piloted aircraft climbs to a record-setting altitude of 50,567 feet during a flight Sept. 11, 1995, at NASA's Dryden Flight Research Center, Edwards, California. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1995-01-01

124

Artificial Coral Reefs  

NSDL National Science Digital Library

Coral reefs are among the most diverse ecosystems on the planet...and the most threatened. Artificial reefs may help stem the loss of these valuable and beautiful habitats, with shipwrecks, old subway cars, and other structures taking the place of living coral or rocky outcrops. The following Web sites introduce artificial reefs, reef ecology, and some ongoing efforts to establish reef communities in the U.S. and beyond. PBS's NATURE offers a fascinating look at the artificial reefs created by the thousands of shipwrecks and downed planes from World War II that riddle the South Pacific (1). This is the companion Web site to the documentary War Wrecks of the Coral Seas, and it includes some great multimedia features. The next site comes from the National Oceanic and Atmospheric Administration and contains an excellent photo gallery of coral ecosystems around the world (2). The collection includes six pages of artificial reef photos taken in the Pacific. The following site comes from the online companion to the BBC's acclaimed documentary series The Blue Planet. Based on the episode The Web of Life, this site offers a fun, multimedia challenge for learning about and testing one's knowledge of coral reefs (3). The site includes a section on artificial reefs (click on Take it Further). Next, an August 2001 segment from National Public Radio's All Things Considered explores efforts to create artificial reefs using decommissioned New York City subway cars -- a project of Delaware's Department of Natural Resources and Environmental Control in the Division of Fish and Wildlife (4). Likewise, the non-profit group Artificial Reefs of the Keys is working to bring a de-commissioned military ship to the Florida Keys (5). The New Jersey Scuba Diver Web site provides an excellent introduction to artificial reef ecology; focused on reefs in New Jersey, of course. The mini-tutorial comes courtesy of William Figly, Principal Fisheries Biologist for the New Jersey Artificial Reef Program (6). The Fall 2001 issue of California Wild, the magazine of the California Academy of Sciences, addresses the benefits and concerns of off shore oil rigs becoming artificial reefs (7). Finally, visitors will find dozens of news articles and Web links related to artificial reefs in this entry, a page from the New England Artificial Reef Society Web site (8).

Sohmer, Rachel.

125

New directions in coral reef microbial ecology.  

PubMed

Microbial processes largely control the health and resilience of coral reef ecosystems, and new technologies have led to an exciting wave of discovery regarding the mechanisms by which microbial communities support the functioning of these incredibly diverse and valuable systems. There are three questions at the forefront of discovery: What mechanisms underlie coral reef health and resilience? How do environmental and anthropogenic pressures affect ecosystem function? What is the ecology of microbial diseases of corals? The goal is to understand the functioning of coral reefs as integrated systems from microbes and molecules to regional and ocean-basin scale ecosystems to enable accurate predictions of resilience and responses to perturbations such as climate change and eutrophication. This review outlines recent discoveries regarding the microbial ecology of different microenvironments within coral ecosystems, and highlights research directions that take advantage of new technologies to build a quantitative and mechanistic understanding of how coral health is connected through microbial processes to its surrounding environment. The time is ripe for natural resource managers and microbial ecologists to work together to create an integrated understanding of coral reef functioning. In the context of long-term survival and conservation of reefs, the need for this work is immediate. PMID:21955796

Garren, Melissa; Azam, Farooq

2012-04-01

126

Coral Reef Ecosystems: The Abiotic Setting  

NSDL National Science Digital Library

This Science Object is the second of four Science Objects in the Coral Reef Ecosystems SciPack. It investigates the abiotic characteristics that affect the coral reef ecosystem. The number and kinds of organisms found along each reef depend on the physical conditions of the environment and resources available, including food, light, water quality, temperature, and other organisms living in the reef. If conditions change significantly due to changes in climate, loss of food sources, excessive predation, or loss of habitat, the health and stability of the ecosystem will be affected. Like many complex systems, coral ecosystems tend to have cyclic fluctuations around a state of rough equilibrium. In the long run, if conditions remain reasonably constant a coral ecosystem can be stable for hundreds of years. Learning Outcomes:? Identify the characteristics of an ecosystem, and describe the interdependence between biotic and abiotic features in an ecosystem.? Describe how the following abiotic factors provide coral with the energy needed to survive and grow within their ecosystem: sunlight, water, oxygen, and carbon dioxide.? Describe the optimal environmental conditions for coral reef growth, and explain the process of coral reef development (including the role of available sunlight and calcium).? Explain how the following environmental factors might affect coral ecosystems: increase in dissolved CO2, changes in global temperatures, increase in ocean water turbidity through water pollution.

National Science Teachers Association (NSTA)

2006-11-01

127

LISA Pathfinder Science Operations Concept and Development  

NASA Astrophysics Data System (ADS)

LISA Pathfinder is the second of the ESA Small Missions for Advanced Research in Technology, is a dedicated technology demonstrator for the joint ESA/NASA Laser Interferometer Space Antenna (LISA) mission. LISA Pathfinder carries two payloads, the European provided LISA Technology Package (LTP) and the NASA provided Disturbance Reduction System (DRS). The ground segment for LPF in the operational configuration will consist of one ground track-ing station, Cebreros (Spain), the Mission Operations Centre (MOC) at ESOC (Darmstadt, Germany), the Science Technology Operations Centre (STOC) located at ESOC and ESAC (Madrid, Spain) and LTP and DRS teams. The Science Technology Operations Centre although initially a small entity compatible with the operational requirements for an ESA SMART, has evolved in complexity in the last few years containing most of the systems and interfaces included as part of a normal ESA Science Operations Centre. In order to maintain a reasonable cost approach for its development and operations, a general reuse philosophy from systems already tested in previous ESA missions and/or from industry has been applied for the design and operation concept of the LPF STOC. The present paper describes the current LPF STOC design and it foreseen operational concept, highlighting the general reuse and customization process carried out for each of their individual subsystems.

Fauste, Jorge; McNamara, Paul; Armano, Michele; Texier, Damien; Freschi, Marco

128

In-flight Diagnostics in LISA Pathfinder  

E-print Network

LISA PathFinder (LPF) will be flown with the objective to test in space key technologies for LISA. However its sensitivity goals are, for good reason, one order of magnitude less than those which LISA will have to meet, both in drag-free and optical metrology requirements, and in the observation frequency band. While the expected success of LPF will of course be of itself a major step forward to LISA, one might not forget that a further improvement by an order of magnitude in performance will still be needed. Clues for the last leap are to be derived from proper disentanglement of the various sources of noise which contribute to the total noise, as measured in flight during the PathFinder mission. This paper describes the principles, workings and requirements of one of the key tools to serve the above objective: the diagnostics subsystem. This consists in sets of temperature, magnetic field, and particle counter sensors, together with generators of controlled thermal and magnetic perturbations. At least during the commissioning phase, the latter will be used to identify feed-through coefficients between diagnostics sensor readings and associated actual noise contributions. A brief progress report of the current state of development of the diagnostics subsystem will be given as well.

Alberto Lobo; Miquel Nofrarias; Juan Ramos-Castro; Josep Sanjuan; Aleix Conchillo; Jose Antonio Ortega; Xevi Xirgu; Henrique Araujo; Cesar Boatella; Mokhtar Chmeissani; Catia Grimani; Carles Puigdengoles; Peter Wass; Enrique Garcia-Berro; Sergi Garcia; Lluis Martinez; Gustau Montero

2006-12-23

129

Overhead View of Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

Planimetric (overhead view) map of the landing site, to a distance of 20 meters from the spacecraft. North is at the top in this and Plates 3-5. To produce this map, images were geometrically projected onto an assumed mean surface representing the ground. Features above the ground plane (primarily rocks) therefore appear displaced radially outward; the amount of distortion increases systematically with distance. The upper surfaces of the lander and rover also appear enlarged and displaced because of their height. Primary grid (white) is based on the Landing Site Cartographic (LSC) coordinate system, defined with X eastward, Y north, and Z up, and origin located at the mean ground surface immediately beneath the deployed position of the IMP camera gimbal center. Secondary ticks (cyan) are based on the Mars local level (LL) frame, which has X north, Y east, Z down, with origin in the center of the lander baseplate. Rover positions (including APXS measurements) are commonly reported in the LL frame. Yellow grid shows polar coordinates based on the LSC system. Cartographic image processing by U.S. Geological Survey.

NOTE: original caption as published in Science Magazine

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

130

Caribbean-wide decline in carbonate production threatens coral reef growth.  

PubMed

Global-scale deteriorations in coral reef health have caused major shifts in species composition. One projected consequence is a lowering of reef carbonate production rates, potentially impairing reef growth, compromising ecosystem functionality and ultimately leading to net reef erosion. Here, using measures of gross and net carbonate production and erosion from 19 Caribbean reefs, we show that contemporary carbonate production rates are now substantially below historical (mid- to late-Holocene) values. On average, current production rates are reduced by at least 50%, and 37% of surveyed sites were net erosional. Calculated accretion rates (mm?year(-1)) for shallow fore-reef habitats are also close to an order of magnitude lower than Holocene averages. A live coral cover threshold of ~10% appears critical to maintaining positive production states. Below this ecological threshold carbonate budgets typically become net negative and threaten reef accretion. Collectively, these data suggest that recent ecological declines are now suppressing Caribbean reef growth potential. PMID:23360993

Perry, Chris T; Murphy, Gary N; Kench, Paul S; Smithers, Scott G; Edinger, Evan N; Steneck, Robert S; Mumby, Peter J

2013-01-01

131

Impacts and recovery from severe tropical cyclone yasi on the great barrier reef.  

PubMed

Full recovery of coral reefs from tropical cyclone (TC) damage can take decades, making cyclones a major driver of habitat condition where they occur regularly. Since 1985, 44 TCs generated gale force winds (?17 metres/second) within the Great Barrier Reef Marine Park (GBRMP). Of the hurricane strength TCs (?H1-Saffir Simpson scale; ? category 3 Australian scale), TC Yasi (February, 2011) was the largest. In the weeks after TC Yasi crossed the GBRMP, participating researchers, managers and rangers assessed the extent and severity of reef damage via 841 Reef Health and Impact Surveys at 70 reefs. Records were scaled into five damage levels representing increasingly widespread colony-level damage (1, 2, 3) and reef structural damage (4, 5). Average damage severity was significantly affected by direction (north vs south of the cyclone track), reef shelf position (mid-shelf vs outer-shelf) and habitat type. More outer-shelf reefs suffered structural damage than mid-shelf reefs within 150 km of the track. Structural damage spanned a greater latitudinal range for mid-shelf reefs than outer-shelf reefs (400 vs 300 km). Structural damage was patchily distributed at all distances, but more so as distance from the track increased. Damage extended much further from the track than during other recent intense cyclones that had smaller circulation sizes. Just over 15% (3,834 km2) of the total reef area of the GBRMP is estimated to have sustained some level of coral damage, with ~4% (949 km2) sustaining a degree of structural damage. TC Yasi likely caused the greatest loss of coral cover on the GBR in a 24-hour period since 1985. Severely impacted reefs have started to recover; coral cover increased an average of 4% between 2011 and 2013 at re-surveyed reefs. The in situ assessment of impacts described here is the largest in scale ever conducted on the Great Barrier Reef following a reef health disturbance. PMID:25874718

Beeden, Roger; Maynard, Jeffrey; Puotinen, Marjetta; Marshall, Paul; Dryden, Jen; Goldberg, Jeremy; Williams, Gareth

2015-01-01

132

Impacts and Recovery from Severe Tropical Cyclone Yasi on the Great Barrier Reef  

PubMed Central

Full recovery of coral reefs from tropical cyclone (TC) damage can take decades, making cyclones a major driver of habitat condition where they occur regularly. Since 1985, 44 TCs generated gale force winds (?17 metres/second) within the Great Barrier Reef Marine Park (GBRMP). Of the hurricane strength TCs (?H1—Saffir Simpson scale; ? category 3 Australian scale), TC Yasi (February, 2011) was the largest. In the weeks after TC Yasi crossed the GBRMP, participating researchers, managers and rangers assessed the extent and severity of reef damage via 841 Reef Health and Impact Surveys at 70 reefs. Records were scaled into five damage levels representing increasingly widespread colony-level damage (1, 2, 3) and reef structural damage (4, 5). Average damage severity was significantly affected by direction (north vs south of the cyclone track), reef shelf position (mid-shelf vs outer-shelf) and habitat type. More outer-shelf reefs suffered structural damage than mid-shelf reefs within 150 km of the track. Structural damage spanned a greater latitudinal range for mid-shelf reefs than outer-shelf reefs (400 vs 300 km). Structural damage was patchily distributed at all distances, but more so as distance from the track increased. Damage extended much further from the track than during other recent intense cyclones that had smaller circulation sizes. Just over 15% (3,834 km2) of the total reef area of the GBRMP is estimated to have sustained some level of coral damage, with ~4% (949 km2) sustaining a degree of structural damage. TC Yasi likely caused the greatest loss of coral cover on the GBR in a 24-hour period since 1985. Severely impacted reefs have started to recover; coral cover increased an average of 4% between 2011 and 2013 at re-surveyed reefs. The in situ assessment of impacts described here is the largest in scale ever conducted on the Great Barrier Reef following a reef health disturbance. PMID:25874718

Beeden, Roger; Maynard, Jeffrey; Puotinen, Marjetta; Marshall, Paul; Dryden, Jen; Goldberg, Jeremy; Williams, Gareth

2015-01-01

133

Reef Education Evaluation: Environmental Knowledge and Reef Experience  

ERIC Educational Resources Information Center

Background: The Reef education evaluation: environmental knowledge and reef experience report concerns PhD research about marine education, and the investigation of learning with high school students and the effect of coral reef monitoring marine experiential education interventions. The effectiveness of classroom learning and reef trips were…

Stepath, Carl M.

2005-01-01

134

U.S. Coral Reef Taskforce  

NSDL National Science Digital Library

Government task force created in 1998 to research, monitor and conserve coral reefs. Site includes: background on coral reef habitats; reef ecology and environmental requirements; environmental requirements of reefs; reef functions and significance; natural and human threats to reefs. Also covered are: Task Force actions; policies and partnerships; and the National Action Plan for Coral Reef Conservation.

135

Reefs in Crisis  

NSDL National Science Digital Library

This online article, from "The Biodiversity Crisis: Losing What Counts", walks students through the risks humans pose to the survival of coral reefs and conservation efforts. It discusses the forces behind damage to the reefs and recent protection efforts, including the creation of sanctuaries, good land management, and public awareness campaigns.

136

The Coral Reef Environmental \\  

Microsoft Academic Search

Coral reefs have been increasingly reported as ecosystems in severe “crisis” and decline, with estimates of irreparably damaged reefs to be around 54%, and possible losses of 15-20% more over the next half-century. The urgency to mitigate these declines has increased in recent years as the effects of global climate change have become apparent alongside steadily increasing population pressures in

Bärbel G. Bischof

2010-01-01

137

Create a Coral Reef  

NSDL National Science Digital Library

In this hands-on OLogy activity, kids learn about coral reefs by building a diorama. Students are introduced to coral polyps and reefs and given illustrated, step-by-step directions that show how to construct a diorama containing models of a brain coral, a sea fan, a sponge, and sea anemones.

138

Capitol Reef Cliff  

USGS Multimedia Gallery

A sandstone cliff near the entrance of Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth. This l...

139

Capitol Reef Sandstone Monolith  

USGS Multimedia Gallery

A sandstone monolith within Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

140

Capitol Reef Sandstone Cliff  

USGS Multimedia Gallery

A sandstone cliff within Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

141

Capitol Reef Cliff  

USGS Multimedia Gallery

A sandstone cliff near the entrance of Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth.&n...

142

Capitol Reef Cliff  

USGS Multimedia Gallery

A sandstone cliff near the entrance of Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth. The tr...

143

Capitol Reef Panorama  

USGS Multimedia Gallery

A panorama of some of the sandstone formations within Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in th...

144

The Imager for Mars Pathfinder Insurance Pan  

NASA Technical Reports Server (NTRS)

The Imager for Mars Pathfinder (IMP) obtained a full panorama of the Sagan Memorial Station landing site on Sol 2, before the IMP mast was deployed. The images in this panorama were taken in 4 filters (including stereo) and losslessly compressed to provide a high-quality multispectral survey of the landing site even if the IMP mast did not successfully deploy; this data set was therefore called the Insurance Pan. It was completed late in the afternoon of Sol 2, just before the IMP mast was (successfully) deployed. The data were stored in memory and returned to Earth after it became clear that downlink rates were higher than expected. The Insurance Pan horizontal (azimuth) coverage is nearly complete, with gaps caused by pointing errors and data packet losses. Stereo data were acquired in the blue (445 nm) filter, as well as right-eye green (531 nm), orange (600 nm), and near-infrared (752 nm) data.

Herkenhoff, K. E.; Johnson, J. R.; Weller, L. A.

2003-01-01

145

Statechart Analysis with Symbolic PathFinder  

NASA Technical Reports Server (NTRS)

We report here on our on-going work that addresses the automated analysis and test case generation for software systems modeled using multiple Statechart formalisms. The work is motivated by large programs such as NASA Exploration, that involve multiple systems that interact via safety-critical protocols and are designed with different Statechart variants. To verify these safety-critical systems, we have developed Polyglot, a framework for modeling and analysis of model-based software written using different Statechart formalisms. Polyglot uses a common intermediate representation with customizable Statechart semantics and leverages the analysis and test generation capabilities of the Symbolic PathFinder tool. Polyglot is used as follows: First, the structure of the Statechart model (expressed in Matlab Stateflow or Rational Rhapsody) is translated into a common intermediate representation (IR). The IR is then translated into Java code that represents the structure of the model. The semantics are provided as "pluggable" modules.

Pasareanu, Corina S.

2012-01-01

146

Bayesian Model Selection for LISA Pathfinder  

NASA Astrophysics Data System (ADS)

The LISA Pathfinder mission (LPF) aims at validating the displacement and acceleration noise models and to test key technologies for the future LISA mission. The LISA Technology Package (LTP) Data Analysis team has developed complex models of the LTP for simulations and data analysis during the mission. These models contain a large number of parameters to be estimated and for that reason, we need to recover only the essential ones that describe the observations. Being able to distinguish between competing models that describe the data introduces many possible applications in LTP Data Analysis. In our analysis we use two main different approximations to compute the Bayes Factor: the Reversible Jump Markov Chain Monte Carlo (RJMCMC) and the Laplace approximations. They are applied first to toy models and then verified with full LTP models. This work is part of the LTPDA Matlab toolbox.

Karnesis, N.; Nofrarias, M.; Sopuerta, C. F.; Gibert, F.; Lobo, A.

2013-01-01

147

Electrostatic Charging of the Pathfinder Rover  

NASA Technical Reports Server (NTRS)

The Mars Pathfinder mission will send a lander and a rover to the martian surface. Because of the extremely dry conditions on Mars, electrostatic charging of the rover is expected to occur as it moves about. Charge accumulation may result in high electrical potentials and discharge through the martian atmosphere. Such discharge could interfere with the operation of electrical elements on the rover. A strategy was sought to mitigate this charge accumulation as a precautionary measure. Ground tests were performed to demonstrate charging in laboratory conditions simulating the surface conditions expected at Mars. Tests showed that a rover wheel, driven at typical rover speeds, will accumulate electrical charge and develop significant electrical potentials (average observed, 110 volts). Measurements were made of wheel electrical potential, and wheel capacitance. From these quantities, the amount of absolute charge was estimated. An engineering solution was developed and recommended to mitigate charge accumulation. That solution has been implemented on the actual rover.

Siebert, Mark W.; Kolecki, Joseph C.

1996-01-01

148

Modal analysis of PATHFINDER unmanned air vehicle  

SciTech Connect

An experimental modal analysis was performed on PATHFINDER, a 450-lb, 100-ft wing span, flying-wing-design aircraft powered by solar/electric motors. The aircraft was softly suspended and then excited using random input from a long-stroke shaker. Modal data was taken from 92 measurement locations on the aircraft using newly designed, lightweight, tri-axial accelerometers. A conventional PC-based data acquisition system provided data handling. Modal parameters were calculated, and animated mode shapes were produced using SMS STARStruct{trademark} Modal Analysis System software. The modal parameters will be used for validation of finite element models, optimum placement of onboard accelerometers during flight testing, and vibration isolation design of sensor platforms.

Woehrle, T.G.; Costerus, B.W.; Lee, C.L.

1994-10-19

149

360 Degree Panorama Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

This is the first contiguous, uniform 360-degree color panorama taken by the Imager for Mars Pathfinder (IMP) over the course of sols 8, 9, and 10 (Martian days). Different regions were imaged at different times over the three Martian days to acquire consistent lighting and shadow conditions for all areas of the panorama. At left is a lander petal and a metallic mast which is a portion of the low-gain antenna. On the horizon the double 'Twin Peaks' are visible, about 1-2 kilometers away. The rock 'Couch' is the dark, curved rock at right of Twin Peaks. Another lander petal is at left-center, showing the fully deployed forward ramp at far left, and rear ramp at right, which rover Sojourner used to descend to the surface of Mars on July 5. Immediately to the left of the rear ramp is the rock Barnacle Bill, which scientists found to be andesitic, possibly indicating that it is a volcanic rock (a true andesite) or a physical mixture of particles. Just beyond Barnacle Bill, rover tracks lead to Sojourner, shown using its Alpha Proton X-Ray Spectrometer (APXS) instrument to study the large rock Yogi. Yogi, low in quartz content, appears to be more primitive than Barnacle Bill, and appeared more like the common basalts found on Earth. The tracks and circular pattern in the soil leading up to Yogi were part of Sojourner's soil mechanics experiments, in which varying amounts of pressure were applied to the wheels in order to determine physical properties of the soil. During its traverse to Yogi the rover stirred the soil and exposed material from several centimeters in depth. During one of the turns to deploy Sojourner's Alpha Proton X-Ray Spectrometer, the wheels dug particularly deeply and exposed white material. Spectra of this white material show it is virtually identical to the rock Scooby Doo, and such white material may underlie much of the site. Deflated airbags are visible at the perimeter of all three lander petals. The IMP is a stereo imaging system with color capability provided by 24 selectable filters, twelve filters per 'eye.' Its red, green, and blue filters were used to take this image. The IMP, in its fully deployed configuration, stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters. Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

1997-01-01

150

Imager for Mars Pathfinder (IMP) image calibration  

USGS Publications Warehouse

The Imager for Mars Pathfinder returned over 16,000 high-quality images from the surface of Mars. The camera was well-calibrated in the laboratory, with <5% radiometric uncertainty. The photometric properties of two radiometric targets were also measured with 3% uncertainty. Several data sets acquired during the cruise and on Mars confirm that the system operated nominally throughout the course of the mission. Image calibration algorithms were developed for landed operations to correct instrumental sources of noise and to calibrate images relative to observations of the radiometric targets. The uncertainties associated with these algorithms as well as current improvements to image calibration are discussed. Copyright 1999 by the American Geophysical Union.

Reid, R.J.; Smith, P.H.; Lemmon, M.; Tanner, R.; Burkland, M.; Wegryn, E.; Weinberg, J.; Marcialis, R.; Britt, D.T.; Thomas, N.; Kramm, R.; Dummel, A.; Crowe, D.; Bos, B.J.; Bell, J.F., III; Rueffer, P.; Gliem, F.; Johnson, J.R.; Maki, J.N.; Herkenhoff, K.E.; Singer, R.B.

1999-01-01

151

Pathfinder autonomous rendezvous and docking project  

NASA Technical Reports Server (NTRS)

Capabilities are being developed and demonstrated to support manned and unmanned vehicle operations in lunar and planetary orbits. In this initial phase, primary emphasis is placed on definition of the system requirements for candidate Pathfinder mission applications and correlation of these system-level requirements with specific requirements. The FY-89 activities detailed are best characterized as foundation building. The majority of the efforts were dedicated to assessing the current state of the art, identifying desired elaborations and expansions to this level of development and charting a course that will realize the desired objectives in the future. Efforts are detailed across all work packages in developing those requirements and tools needed to test, refine, and validate basic autonomous rendezvous and docking elements.

Lamkin, Stephen (editor); Mccandless, Wayne (editor)

1990-01-01

152

Java PathFinder User Guide  

NASA Technical Reports Server (NTRS)

The JAVA PATHFINDER, JPF, is a translator from a subset of JAVA 1.0 to PROMELA, the programming language of the SPIN model checker. The purpose of JPF is to establish a framework for verification and debugging of JAVA programming based on model checking. The main goal is to automate program verification such that a programmer can apply it in the daily work without the need for a specialist to manually reformulate a program into a different notation in order to analyze the program. The system is especially suited for analyzing multi-threaded JAVA applications, where normal testing usually falls short. The system can find deadlocks and violations of boolean assertions stated by the programmer in a special assertion language. This document explains how to Use JPF.

Havelund, Klaus

1999-01-01

153

Model Checking JAVA Programs Using Java Pathfinder  

NASA Technical Reports Server (NTRS)

This paper describes a translator called JAVA PATHFINDER from JAVA to PROMELA, the "programming language" of the SPIN model checker. The purpose is to establish a framework for verification and debugging of JAVA programs based on model checking. This work should be seen in a broader attempt to make formal methods applicable "in the loop" of programming within NASA's areas such as space, aviation, and robotics. Our main goal is to create automated formal methods such that programmers themselves can apply these in their daily work (in the loop) without the need for specialists to manually reformulate a program into a different notation in order to analyze the program. This work is a continuation of an effort to formally verify, using SPIN, a multi-threaded operating system programmed in Lisp for the Deep-Space 1 spacecraft, and of previous work in applying existing model checkers and theorem provers to real applications.

Havelund, Klaus; Pressburger, Thomas

2000-01-01

154

Exobiology site priorities for Mars Pathfinder  

NASA Technical Reports Server (NTRS)

The fact that life developed on the Earth within the first billion years of its history makes it quite plausible that life may have also developed on Mars. If life did develop on Mars, it undoubtedly left behind a fossil record. Such a fossil record is likely to be more accessible than either subsurface environments that may harbor life, or scattered 'oases' that may be present at the surface. Consequently, the post-Viking approach of Mars exobiology has shifted focus to search for evidence of an ancient martian biosphere. This has led to the emergence of a new subdiscipline of paleontology, herein termed 'exopaleontology', which deals with the exploration for fossils on other planets and whose core concepts derive from Earth-based Precambrian paleontology, microbial ecology, and sedimentology. Potential targets on Mars for subaqueous spring deposits, sedimentary cements, and evaporites are ancient terminal lake basins where hydrological systems could have endured for some time under arid conditions. Potential targets for the Mars Pathfinder mission include channeled impact craters and areas of deranged drainage associated with outflows in northwest Arabia and Xanthe Terra, where water may have ponded temporarily to form lakes. The major uncertainty of such targets is their comparatively younger age and the potentially short duration of hydrological activity compared to older paleolake basins found in the southern hemisphere. However, it has been suggested that cycles of catastrophic flooding associated with Tharsis volcanism may have sustained a large body of water, Oceanus Borealis, in the northern plains area until quite late in martian history. Although problematic, the shoreline areas of the proposed northern ocean provide potential targets for a Mars Pathfinder mission aimed at exploring for carbonates or other potentially fossiliferous marine deposits. Carbonates and evaporites possess characteristic spectra signatures in the near-infrared and should be detectable using rover-based spectroscopy and other methods for in situ mineralogical analysis.

Farmer, Jack D.; Desmarais, David J.

1994-01-01

155

Topographic Map of Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

Topographic map of the landing site, to a distance of 60 meters from the lander in the LSC coordinate system. The lander is shown schematically in the center; 2.5 meter radius circle (black) centered on the camera was not mapped. Gentle relief [root mean square (rms) elevation variation 0.5 m; rms a directional slope 4O] and organization of topography into northwest and northeast-trending ridges about 20 meters apart are apparent. Roughly 30% of the illustrated area is hidden from the camera behind these ridges. Contours (0.2 m interval) and color coding of elevations were generated from a digital terrain model, which was interpolated by kriging from approximately 700 measured points. Angular and parallax point coordinates were measured manually on a large (5 m length) anaglyphic uncontrolled mosaic and used to calculate Cartesian (LSC) coordinates. Errors in azimuth on the order of 10 are therefore likely; elevation errors were minimized by referencing elevations to the local horizon. The uncertainty in range measurements increases quadratically with range. Given a measurement error of 1/2 pixel, the expected precision in range is 0.3 meter at 10 meter range, and 10 meters at 60 meter range. Repeated measurements were made, compared, and edited for consistency to improve the range precision. Systematic errors undoubtedly remain and will be corrected in future maps compiled digitally from geometrically controlled images. Cartographic processing by U.S. Geological Survey.

NOTE: original caption as published in Science Magazine

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

156

Impact of sea-level rise and coral mortality on the wave dynamics and wave forces on barrier reefs.  

PubMed

A one-dimensional wave model was used to investigate the reef top wave dynamics across a large suite of idealized reef-lagoon profiles, representing barrier coral reef systems under different sea-level rise (SLR) scenarios. The modeling shows that the impacts of SLR vary spatially and are strongly influenced by the bathymetry of the reef and coral type. A complex response occurs for the wave orbital velocity and forces on corals, such that the changes in the wave dynamics vary reef by reef. Different wave loading regimes on massive and branching corals also leads to contrasting impacts from SLR. For many reef bathymetries, wave orbital velocities increase with SLR and cyclonic wave forces are reduced for certain coral species. These changes may be beneficial to coral health and colony resilience and imply that predicting SLR impacts on coral reefs requires careful consideration of the reef bathymetry and the mix of coral species. PMID:24768171

Baldock, T E; Golshani, A; Callaghan, D P; Saunders, M I; Mumby, P J

2014-06-15

157

Life on the Reef  

NSDL National Science Digital Library

This Expeditions Web site takes an in-depth look at life on one of the world's largest barrier reefs. The site begins with a brief explanation of the expedition and what its participants were looking to find. Dive the Reef is an interactive feature that allows students to learn what separates a lagoon from a reef from a shelf. Meet the Scientists has brief biographies of the 14 team members who participated in the expedition. At the Museum is an article that discusses the selection of the barrier reef system of Andros Island as well as the AMNH's long history of Bahamian research. The Reef from Space explains how NASA's computer-enhanced pictures from space contributed to the expedition's findings. The site also includes 12 dispatches written during the expedition, which can be found in the Today from the Bahamas section.

158

Ecology of mesophotic coral reefs  

Microsoft Academic Search

Mesophotic coral reefs, reefs at depths of 30 m to 150 m, are receiving renewed interest from coral reef scientists and managers because they are linked physically and biologically to their shallow water counterparts, have the potential to be refugia for shallow coral reef taxa such as coral and sponges, and can be a source of larvae that could contribute to the

Michael P. Lesser; Marc Slattery; James J. Leichter

2009-01-01

159

Assessing the ‘deep reef refugia’ hypothesis: focus on Caribbean reefs  

Microsoft Academic Search

Coral reefs in shallow-water environments (<30 m) are in decline due to local and global anthropogenic stresses. This has\\u000a led to renewed interest in the ‘deep reef refugia’ hypothesis (DRRH), which stipulates that deep reef areas (1) are protected\\u000a or dampened from disturbances that affect shallow reef areas and (2) can provide a viable reproductive source for shallow\\u000a reef areas following

P. Bongaerts; T. Ridgway; E. M. Sampayo; O. Hoegh-Guldberg

2010-01-01

160

ReefBase, A Global Information System on Coarl Reefs  

NSDL National Science Digital Library

ReefBase is an online information system dedicated to coral reefs. The site aims to facilitate sustainable management of coral reefs and related coastal/marine environments. Included are data and information on the location, status, threats, monitoring, legislation, and management of coral reefs in 131 countries, extensive data on coral bleaching, a state-of-the-art online mapping-system that allows custom-made maps of coral reefs and related datasets, and an extensive bibliography of publications.

ReefBase

161

Pathfinder aircraft taking off from ground - side view  

NASA Technical Reports Server (NTRS)

This 27-second video clip shows the Pathfinder taking off from Rogers Dry Lakebed near the NASA Dryden Flight Research Center on Edwards Air Force Base. Shown from the lakebed side, the video shows Edwards and Dryden in the background.

1995-01-01

162

Mars Pathfinder: Latest citations from the Aerospace Database  

NASA Astrophysics Data System (ADS)

The bibliography contains citations concerning the NASA Pathfinder mission on Mars' geochronology, geomorphology, and geology. References discuss the Martian atmosphere, surface environments, minerals, landers, and roving vehicles. Mission planning, ground support systems, operations concepts, and data information systems are covered.

1997-08-01

163

Dust on Mars: Materials Adherence Experiment results from Mars Pathfinder  

SciTech Connect

Mars Pathfinder is the first solar-powered probe to operate on the surface of Mars. Pathfinder consists of a lander and a small, autonomous, six-wheel solar-powered rover, Sojourner. The Pathfinder spacecraft reflects NASA`s new philosophy of exploiting new technologies to reduce mission cost. The Materials Adherence Experiment on Pathfinder was designed to measure the degradation of solar arrays due to dust settling out of the atmosphere and blocking light to the solar array, lowering the array power output. The MAE measurements indicate steady dust accumulation at a rate of about 0.28% per day. This value is consistent with the performance of the solar arrays, which have decreased in power at an estimated rate of 0.29% per day.

Landis, G.A.; Jenkins, P.P. [NASA Lewis Research Center, Cleveland, OH (United States)

1997-12-31

164

Launch Abort System Pathfinder Arrival - Duration: 1:48.  

NASA Video Gallery

The Orion Launch Abort System, or LAS, pathfinder returned home to NASA Langley on Oct. 18 on its way to NASA's Kennedy Space Center. The hardware was built at Langley and was used in preparation f...

165

Pathfinder aircraft taking off - setting new solar powered altitude record  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered remotely piloted aircraft climbs to a record-setting altitude of 50,567 feet during a flight Sept. 11, 1995, at NASA's Dryden Flight Research Center, Edwards, California. The flight was part of the NASA ERAST (Environmental Research Aircraft and Sensor Technology) program. The Pathfinder was designed and built by AeroVironment Inc., Monrovia, California. Solar arrays cover nearly all of the upper wing surface and produce electricity to power the aircraft's six motors. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1995-01-01

166

CENSSIS SEABED: DIVERSE APPROACHES FORCENSSIS SEABED: DIVERSE APPROACHES FOR IMAGING SHALLOW AND DEEP CORAL REEFSIMAGING SHALLOW AND DEEP CORAL REEFS  

E-print Network

AND DEEP CORAL REEFSIMAGING SHALLOW AND DEEP CORAL REEFS Fernando Gilbes,Fernando Gilbes, Roy ArmstrongBED for the development of improved remote sensing techniques for monitoring coral reefs. SeaBED includes both controlled coral reef zones, different species, and coral health conditions with a submersible spectroradiometer

Gilbes, Fernando

167

New protection initiatives announced for coral reefs  

NASA Astrophysics Data System (ADS)

Off the coasts of some of the South Pacific's most idyllic-sounding atolls, Austin Bowden-Kerby has seen first-hand the heavy damage to coral reefs from dynamite and cyanide fishing. For instance, while snorkeling near Chuuk, an island in Micronesia, he has observed craters and rubble beds of coral, which locals have told him date to World War II ordnance.A marine biologist and project scientist for the Coral Gardens Initiative of the Foundation for the Peoples of the South Pacific, Bowden-Kerby has also identified what he says are some public health effects related to destroyed coral reefs and their dying fisheries. These problems include protein and vitamin A deficiency and blindness, all of which may—in some instances—be linked to poor nutrition resulting from lower reef fish consumption by islanders, according to Bowden-Kerby.

Showstack, Randy

168

Coral Reef Ecosystems: Interdependence  

NSDL National Science Digital Library

This Science Object is the third of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the interdependent relationships between species in the coral reef ecosystem. All populations in the reef ecosystem are a part of and depend on a global food web (a connected set of food chains) through which energy flows in one direction, from the sun into organism and eventually dissipating into the environment as heat. This food web includes ocean plants, the animals that feed on them, and the animals that feed on those animals. Energy is transferred between organisms and their environment along the way. Energy concentration diminishes at each step. The cycles of life continue indefinitely because organisms decompose after death and return food materials to the environment. Learning Outcomes:? Identify and label key components of food chains and food webs in a coral reef ecosystem.? Describe key relationships among plants and animals in the coral reef ecosystem: predator and prey relationships, producer and consumer relationships, and symbiotic relationships (mutualism, commensalisms, parasitism).? Recognize the direction that energy travels through food chains and food webs.? Explain that materials (chemical elements) and natural resources are recycled in coral reef ecosystems and reappear in different forms.? Describe the primary ecological succession events within a typical coral reef ecosystem.

National Science Teachers Association (NSTA)

2006-11-01

169

ReefBase: A Global Information System on Coral Reefs  

NSDL National Science Digital Library

ReefBase, a comprehensive Web portal for information on coral reefs, is presented by the World Fish Center based in Malaysia. Intended for use by reef managers, scientists, and the general public, ReefBase aims to "facilitate better understanding of the interdependence between humans and coral reefs, in order to benefit management and conservation efforts of these important resources." ReefBase provides information on coastal and marine resources, coral reef threats, resource management practices, maps and photos, references, and more. Users can quickly search for information organized by country or territory using a convenient dropdown menu. ReefBase is frequently updated; one recent addition is a status report for coral reefs of the southwestern Indian Ocean.

Noordeloos, Machiel E.

170

10th Anniversary Review: a changing climate for coral reefs.  

PubMed

Tropical coral reefs are charismatic ecosystems that house a significant proportion of the world's marine biodiversity. Their valuable goods and services are fundamental to the livelihood of large coastal populations in the tropics. The health of many of the world's coral reefs, and the goods and services they provide, have already been severely compromised, largely due to over-exploitation by a range of human activities. These local-scale impacts, with the appropriate government instruments, support and management actions, can potentially be controlled and even ameliorated. Unfortunately, other human actions (largely in countries outside of the tropics), by changing global climate, have added additional global-scale threats to the continued survival of present-day coral reefs. Moderate warming of the tropical oceans has already resulted in an increase in mass coral bleaching events, affecting nearly all of the world's coral reef regions. The frequency of these events will only increase as global temperatures continue to rise. Weakening of coral reef structures will be a more insidious effect of changing ocean chemistry, as the oceans absorb part of the excess atmospheric carbon dioxide. More intense tropical cyclones, changed atmospheric and ocean circulation patterns will all affect coral reef ecosystems and the many associated plants and animals. Coral reefs will not disappear but their appearance, structure and community make-up will radically change. Drastic greenhouse gas mitigation strategies are necessary to prevent the full consequences of human activities causing such alterations to coral reef ecosystems. PMID:18175015

Lough, Janice M

2008-01-01

171

Selection of the Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

The Mars Pathfinder spacecraft will land on a depositional fan near the mouth of the catastrophic outflow channel, Ares Vallis (19.5 deg N, 32.8 deg W). This site offers the prospect of analyzing a variety of rock types from the ancient cratered highlands, intermediate-age ridged plains, and reworked channel deposits. Analyses of these rocks by Pathfinder instruments will enable first-order scientific questions to be addressed, such as differentiation of the crust, the development of weathering products, and the nature of the early environment, as well as their subsequent evolution on Mars. Constraints imposed by: (1) spacecraft and rover designs (which are robust), (2) entry, descent, and landing, (3) scientific potential at various sites, and (4) safety were important considerations in site selection. Engineering constraints require a 70 km by 200 km smooth, flat (low slopes) area located between 10 deg and 20 deg N that is below 0 km elevation, with average radar reflectivity, little dust, and moderate rock abundance. Three regions on Mars are between 10 deg and 20 deg N and below 0 km elevation: Chryse, Amazonis, and Isidis-Elysitun. Science considerations favor sites at the mouths of outflow channels (grab bag sites offer an assay of rock types on Mars), highland sites (early crustal differentiation and climate), and sites covered with dark (unoxidized) material. Sites are considered safe if they are clearly below 0 km elevation, appear acceptably free of hazards in high-resolution (less than 50 m/pixel) Viking orbiter images and have acceptable reflectivity and roughness at radar wavelengths, thermal inertia, rock abundance, red to violet ratio, and albedo. Recent 3.5-cm wavelength radar observations were used to verify elevation, reflectivity, and roughness within the landing ellipses. Three sites meet all of these criteria: Ares Vallis, Tritonis Lacus, and Isidis. Although Isidis appears to be safer than Tritonis and Ares, the greater scientific potential at Ares Vallis resulted in its selection. Comparisons of the Grand Coulee (channel) and the depositional Ephrata Fan of the Channeled Scabland in eastern Washington, with Ar-es Vallis and its depositional fan also suggest the Ares Vallis landing site is safe and scientifically interesting.

Golombek, M. P.; Cook, R. A.; Moore, H. J.; Parker, T. J.

1997-01-01

172

Bayesian Model Selection for LISA Pathfinder  

E-print Network

The main goal of the LISA Pathfinder (LPF) mission is to fully characterize the acceleration noise models and to test key technologies for future space-based gravitational-wave observatories similar to the eLISA concept. The data analysis team has developed complex three-dimensional models of the LISA Technology Package (LTP) experiment on-board LPF. These models are used for simulations, but more importantly, they will be used for parameter estimation purposes during flight operations. One of the tasks of the data analysis team is to identify the physical effects that contribute significantly to the properties of the instrument noise. A way of approaching this problem is to recover the essential parameters of a LTP model fitting the data. Thus, we want to define the simplest model that efficiently explains the observations. To do so, adopting a Bayesian framework, one has to estimate the so-called Bayes Factor between two competing models. In our analysis, we use three main different methods to estimate it: The Reversible Jump Markov Chain Monte Carlo method, the Schwarz criterion, and the Laplace approximation. They are applied to simulated LPF experiments where the most probable LTP model that explains the observations is recovered. The same type of analysis presented in this paper is expected to be followed during flight operations. Moreover, the correlation of the output of the aforementioned methods with the design of the experiment is explored.

Nikolaos Karnesis; Miquel Nofrarias; Carlos F. Sopuerta; Ferran Gibert; Michele Armano; Heather Audley; Giuseppe Congedo; Ingo Diepholz; Luigi Ferraioli; Martin Hewitson; Mauro Hueller; Natalia Korsakova; Eric Plagnol; and Stefano Vitale

2014-06-05

173

The Mars Pathfinder Mission and Science Results  

NASA Astrophysics Data System (ADS)

Mars Pathfinder, the first low-cost, quick Discovery class mission to be completed, successfully landed on the surface of Mars on July 4, 1997, deployed and navigated a small rover, and collected data from 3 science instruments and 10 technology experiments. The mission operated on Mars for 3 months and returned 2.3 Gbits of new data, including over 16,500 lander and 550 rover images, 16 chemical analyses of rocks and soil, and 8.5 million individual temperature, pressure and wind measurements. The rover traversed 100 m clockwise around the lander, exploring about 200 square meters of the surface. The mission captured the imagination of the public, and garnered front page headlines during the first week. A total of about 566 million internet "hits" were registered during the first month of the mission, with 47 million "hits" on July 8th alone, making the Pathfinder landing by far the largest internet event in history at the time. Pathfinder was the first mission to deploy a rover on Mars. It carried a chemical analysis instrument, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which provided a calibration point or "ground truth" for orbital remote sensing observations. The combination of spectral imaging of the landing area by the lander camera, chemical analyses aboard the rover, and close-up imaging of colors, textures and fabrics with the rover cameras offered the potential of identifying rocks (petrology and mineralogy). With this payload, a landing site in Ares Vallis was selected because it appeared acceptably safe and offered the prospect of analyzing a variety of rock types expected to be deposited by catastrophic floods, which enabled addressing first-order scientific questions such as differentiation of the crust, the development of weathering products, and the nature of the early Martian environment and its subsequent evolution. The 3 instruments and rover allowed seven areas of scientific investigation: the geology and geomorphology of the surface, mineralogy and geochemistry of rocks and soils, physical properties of surface materials, magnetic properties of airborne dust, atmospheric science including aerosols, and rotational and orbital dynamics of Mars. Scientists were assembled into 7 Science Operations Groups that were responsible for requesting measurements by the 3 instruments, rover and engineering subsystems for carrying out their scientific investigations and for analyzing the data and reporting on their findings. The spacecraft was launched on December 4, 1996 and had a 7 month cruise to Mars, with four trajectory correction maneuvers. The vehicle entered the atmosphere directly following cruise stage separation. Parachute deployment, heatshield and lander separation, radar ground acquisition, airbag inflation and rocket ignition all occurred before landing at 2:58 AM true local solar time (9:56:55 AM PDT). The lander bounced at least 15 times up to 12 in high without airbag rupture, demonstrating the robustness of this landing system. Reconstruction of the final landing sequence indicates that the parachute/backshel1/1ander was tilted due to a northwest directed wind and wind shear, which resulted in the lander bouncing about I km to the northwest and initially downhill about 20 m from where the solid rockets fired. Two anomalously bright spots located in the lander scene are likely the heatshield, which continued in a ballistic trajectory about 2 km downrange (west southwest), and the backshell/parachute, which stayed nearer to where the rockets fired. Unconnected disturbed soil patches in the scene indicate that the final few bounces of the lander were from the east-southeast and were followed by a gentle roll to the west before coming to rest on the base petal. The location of the lander away from where the solid rockets fired and considerations of the exhaust products used to inflate the airbags and their fate, indicate that the Pathfinder landing system is one of the cleanest designed leaving the local area essentia

Golombek, M. P.

1999-01-01

174

Australia's Great Barrier Reef  

NASA Technical Reports Server (NTRS)

The Great Barrier Reef extends for 2,000 kilometers along the northeastern coast of Australia. It is not a single reef, but a vast maze of reefs, passages, and coral cays (islands that are part of the reef). This nadir true-color image was acquired by the MISR instrument on August 26, 2000 (Terra orbit 3679), and shows part of the southern portion of the reef adjacent to the central Queensland coast. The width of the MISR swath is approximately 380 kilometers, with the reef clearly visible up to approximately 200 kilometers from the coast. It may be difficult to see the myriad details in the browse image, but if you retrieve the higher resolution version, a zoomed display reveals the spectacular structure of the many reefs.

The more northerly coastal area in this image shows the vast extent of sugar cane cultivation, this being the largest sugar producing area in Australia, centered on the city of Mackay. Other industries in the area include coal, cattle, dairying, timber, grain, seafood, and fruit. The large island off the most northerly part of the coast visible in this image is Whitsunday Island, with smaller islands and reefs extending southeast, parallel to the coast. These include some of the better known resort islands such as Hayman, Lindeman, Hamilton, and Brampton Islands.

Further south, just inland of the small semicircular bay near the right of the image, is Rockhampton, the largest city along the central Queensland coast, and the regional center for much of central Queensland. Rockhampton is just north of the Tropic of Capricorn. Its hinterland is a rich pastoral, agricultural, and mining region.

MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

2001-01-01

175

Coral Reef Ecosystems  

NASA Astrophysics Data System (ADS)

Coral reefs are geological structures of significant dimensions, constructed over millions of years by calcifying organisms. The present day reef-builders are hard corals belonging to the order Scleractinia, phylum Cnidaria. The greatest concentrations of coral reefs are in the tropics, with highest levels of biodiversity situated in reefs of the Indo-West Pacific region. These ecosystems have provided coastal protection and livelihood to human populations over the millennia. Human activities have caused destruction of these habitats, the intensity of which has increased alarmingly since the latter decades of the twentieth century. The severity of this impact is directly related to exponential growth rates of human populations especially in the coastal areas of the developing world. However, a more recently recognized phenomenon concerns disturbances brought about by the changing climate, manifested mainly as rising sea surface temperatures, and increasing acidification of ocean waters due to greater drawdown of higher concentrations of atmospheric carbon dioxide. Management efforts have so far not kept pace with the rates of degradation, so that the spatial extent of damaged reefs and the incidences of localized extinction of reef species are increasing year after year. The major management efforts to date consist of establishing marine protected areas and promoting the active restoration of coral habitats.

Yap, Helen T.

176

An overview of Miocene reefs  

SciTech Connect

Miocene reefs lived approximately within the latitudes of 27{degree}S to 48{degree}N compared with 25{degree}S and 32{degree}N for Holocene reefs. This expansion of reef-growing environments was the result of warm Miocene climates, aided by a eustatic sea level rise and tectonic styles that provided numerous foundations for reef development. The majority of Miocene reefs are found in three main areas: (1) Southeast Asia and the western Pacific, (2) the Mediterranean-Middle East, and (3) Middle America and the Caribbean. These regions, with their distinctive suites of coral and foramineral species, formed three biological provinces; respectively, they are the Indo-Pacific, Tethyan, and Western Atlantic provinces. Miocene reefs in Southeast Asia occur in several foreland basins as patch reef complexes on paleohighs and as barrier reefs in back-arc basins. Those reefs in the Mediterranean occur as fringing reefs, middle-shelf patch reefs, or as barrier reefs on the edges of tectonic blocks associated with Alpine thrust belts. Most reefs in the Caribbean grew on isolated open-ocean highs of volcanic origin. Miocene reefs display a diversity of framework types: (1) coral-encrusting, red algal boundstones with diverse coral faunas, (2) branching coral-encrusting, red algal boundstones with a limited Poritid fauna, (3) encrusting red algal boundstones. Barrier reef systems are especially rich in encrusting red algae and robust corals; grainstones are common as interbedded sediment. Patch reef complexes, however, display muddy carbonate textures, may have less diverse coral faunas, and commonly have larger foraminifera. The global distribution of Miocene reefs is important because (1) it provides insight into a paleoclimatic view of the earth during a major greenhouse stage and (2) Miocene buildups, such as the Arun (EUR of 14 tcf) and Bima fields (EUR of about 100 MMBO), are exploration targets.

Jordan, C.F. Jr. (Mobil Research and Development Corp., Dallas, TX (USA)); Colgan, M.W. (College of Charleston, SC (USA)); Frost, S.H. (Unocal, Los Angeles, CA (USA)); Glenn, E.C. (Phillips Petroleum, Bartlesville, OK (USA)); Bosence, D. (Royal Holloway and Bedford New College, Egham (England)); Esteban, M. (ERICO Petroleum Information Ltd., London (England))

1990-05-01

177

Analyzing the Effects of Climate Change on Sea Surface Temperature in Monitoring Coral Reef Health in the Florida Keys Using Sea Surface Temperature Data  

NASA Technical Reports Server (NTRS)

This presentation discusses use of 4 kilometer satellite-based sea surface temperature (SST) data to monitor and assess coral reef areas of the Florida Keys. There are growing concerns about the impacts of climate change on coral reef systems throughout the world. Satellite remote sensing technology is being used for monitoring coral reef areas with the goal of understanding the climatic and oceanic changes that can lead to coral bleaching events. Elevated SST is a well-documented cause of coral bleaching events. Some coral monitoring studies have used 50 km data from the Advanced Very High Resolution Radiometer (AVHRR) to study the relationships of sea surface temperature anomalies to bleaching events. In partnership with NOAA's Office of National Marine Sanctuaries and the University of South Florida's Institute for Marine Remote Sensing, this project utilized higher resolution SST data from the Terra's Moderate Resolution Imaging Spectroradiometer (MODIS) and AVHRR. SST data for 2000-2010 was employed to compute sea surface temperature anomalies within the study area. The 4 km SST anomaly products enabled visualization of SST levels for known coral bleaching events from 2000-2010.

Jones, Jason; Burbank, Renane; Billiot, Amanda; Schultz, Logan

2011-01-01

178

Impact Of Coral Structures On Wave Directional Spreading Across A Shallow Reef Flat - Lizard Island, Northern Great Barrier Reef  

NASA Astrophysics Data System (ADS)

Coral reef hydrodynamics operate at several and overlapping spatial-temporal scales. Waves have the most important forcing function on shallow (< 5 m) reefs as they drive most ecological and biogeochemical processes by exerting direct physical stress, directly mixing water (temperature and nutrients) and transporting sediments, nutrients and plankton. Reef flats are very effective at dissipating wave energy and providing an important ecosystem service by protecting highly valued shorelines. The effectiveness of reef flats to dissipate wave energy is related to the extreme hydraulic roughness of the benthos and substrate composition. Hydraulic roughness is usually obtained empirically from frictional-dissipation calculations, as detailed field measurements of bottom roughness (e.g. chain-method or profile gauges) is a very labour and time-consuming task. In this study we measured the impact of coral structures on wave directional spreading. Field data was collected during October 2012 across a reef flat on Lizard Island, northern Great Barrier Reef. Wave surface levels were measured using an array of self-logging pressure sensors. A rapid in situ close-range photogrammetric method was used to create a high-resolution (0.5 cm) image mosaic and digital elevation model. Individual coral heads were extracted from these datasets using geo-morphometric and object-based image analysis techniques. Wave propagation was modelled using a modified version of the SWAN model which includes the measured coral structures in 2m by 1m cells across the reef. The approach followed a cylinder drag approach, neglecting skin friction and inertial components. Testing against field data included bed skin friction. Our results show, for the first time, how the variability of the reef benthos structures affects wave dissipation across a shallow reef flat. This has important implications globally for coral reefs, due to the large extent of their area occupied by reef flats, particularly, as global-scale degradation in coral reef health is causing a lowering of reef carbonate production that might lead to a decrease in reef structure and roughness.

Leon, J. X.; Baldock, T.; Callaghan, D. P.; Hoegh-guldberg, O.; Mumby, P.; Phinn, S. R.; Roelfsema, C. M.; Saunders, M. I.

2013-12-01

179

The Status of the Ultra Fast Flash Observatory - Pathfinder  

NASA Astrophysics Data System (ADS)

The Ultra Fast Flash Observatory (UFFO) is a project to study early optical emissions from Gamma Ray Bursts (GRBs). The primary scientific goal of UFFO is to see if GRBs can be calibrated with their rising times, so that they could be used as new standard candles. In order to minimize delay in optical follow-up measurements, which is now about 100 sec after trigger from the Swift experiment, we rotate a mirror to redirect light path so that optical measurement can be performed within a second after the trigger. We have developed a pathfinder mission, UFFO-pathfinder to launch on board the Lomonosov satellite in 2012. In this talk, I will present scientific motivations and descriptions of the design and development of UFFO-pathfinder.

Nam, J. W.; Ahmad, S.; Ahn, K. B.; Barrillon, P.; Brandt, S.; Budtz-Jrgensen, C.; Castro-Tirado, A. J.; Chang, C.-H.; Chang, C.-Y.; Chang, Y. Y.; Chen, C. R.; Chen, P.; Cho, M.; Choi, H. S.; Choi, Y. J.; Connel, P.; Dagoret-Campagne, S.; Eyles, C.; Grossan, B.; Huang, J. J.; Huang, M. H. A.; Jeong, S.; Jung, A.; Kim, J. E.; Kim, M. B.; Kim, S.-W.; Kim, Y. W.; Krasnov, A. S.; Lee, J.; Lim, H.; Linder, E. V.; Liu, T. C.; Lund, N.; Min, K. W.; Na, G. W.; Panasyuk, M. I.; Park, I. H.; Reglero, V.; Ripa, J.; Rodrigo, J. M.; Smoot, G. F.; Suh, J. E.; Svertilov, S.; Vedenkin, N.; Wang, M.-Z.; Yashin, I.

2014-01-01

180

Electronic Pathfinders in Academic Libraries: an Analysis of Their Content and Form.  

ERIC Educational Resources Information Center

Forty-five electronic pathfinders were selected from nine Canadian university libraries to assess their degree of conformity to suggested guidelines in existing literature about pathfinders. Analysis revealed the guidelines were not uniformly followed, leaving some pathfinders more complex and less useful than others. Specific guidelines must be…

Dahl, Candice

2001-01-01

181

U.S. Army pathfinders in World War II: the Mediterranean and Europe  

E-print Network

.S. Army pathfinders between 1943 and the end of the war in an attempt to explain why the U.S. failed to develop this pathfinder technology earlier and why British pathfinder technology was not transferred to the Americans in time for HUSKY. At the same...

Hickenbottom, Richard Scott

1995-01-01

182

Status of Kenyan Coral Reefs  

Microsoft Academic Search

The existence of four marine parks and numerous reefs experiencing intense human resource use has provided the opportunity for a number of studies that have helped increase the understanding of human impacts on Kenyan reefs. Studies indicate that the removal of finfish is having the largest impact on unprotected reefs and has a number of secondary and tertiary effects on

T. R. Mcclanahan; D. Obura

1995-01-01

183

Coral reef bleaching: ecological perspectives  

Microsoft Academic Search

Coral reef bleaching, the whitening of diverse invertebrate taxa, results from the loss of symbiotic zooxanthellae and\\/or a reduction in photosynthetic pigment concentrations in zooxanthellae residing within the gastrodermal tissues of host animals. Of particular concern are the consequences of bleaching of large numbers of reef-building scleractinian corals and hydrocorals. Published records of coral reef bleaching events from 1870 to

P. W. Glynn

1993-01-01

184

Mars Pathfinder Rover-Lewis Research Center Technology Experiments Program  

NASA Astrophysics Data System (ADS)

An overview of NASA's Mars Pathfinder Program is given and the development and role of three technology experiments from NASA's Lewis Research Center and carried on the Mars Pathfinder rover is described. Two recent missions to Mars were developed and managed by the Jet Propulsion Laboratory, and launched late last year: Mars Global Surveyor in November 1996 and Mars Pathfinder in December 1996. Mars Global Surveyor is an orbiter which will survey the planet with a number of different instruments, and will arrive in September 1997, and Mars Pathfinder which consists of a lander and a small rover, landing on Mars July 4, 1997. These are the first two missions of the Mars Exploration Program consisting of a ten year series of small robotic martian probes to be launched every 26 months. The Pathfinder rover will perform a number of technology and operational experiments which will provide the engineering information necessary to design and operate more complex, scientifically oriented surface missions involving roving vehicles and other machinery operating in the martian environment. Because of its expertise in space power systems and technologies, space mechanisms and tribology, Lewis Research Center was asked by the Jet Propulsion Laboratory, which is heading the Mars Pathfinder Program, to contribute three experiments concerning the effects of the martian environment on surface solar power systems and the abrasive qualities of the Mars surface material. In addition, rover static charging was investigated and a static discharge system of several fine Tungsten points was developed and fixed to the rover. These experiments and current findings are described herein.

Stevenson, Steven M.

1997-07-01

185

Mars Pathfinder Rover-Lewis Research Center Technology Experiments Program  

NASA Technical Reports Server (NTRS)

An overview of NASA's Mars Pathfinder Program is given and the development and role of three technology experiments from NASA's Lewis Research Center and carried on the Mars Pathfinder rover is described. Two recent missions to Mars were developed and managed by the Jet Propulsion Laboratory, and launched late last year: Mars Global Surveyor in November 1996 and Mars Pathfinder in December 1996. Mars Global Surveyor is an orbiter which will survey the planet with a number of different instruments, and will arrive in September 1997, and Mars Pathfinder which consists of a lander and a small rover, landing on Mars July 4, 1997. These are the first two missions of the Mars Exploration Program consisting of a ten year series of small robotic martian probes to be launched every 26 months. The Pathfinder rover will perform a number of technology and operational experiments which will provide the engineering information necessary to design and operate more complex, scientifically oriented surface missions involving roving vehicles and other machinery operating in the martian environment. Because of its expertise in space power systems and technologies, space mechanisms and tribology, Lewis Research Center was asked by the Jet Propulsion Laboratory, which is heading the Mars Pathfinder Program, to contribute three experiments concerning the effects of the martian environment on surface solar power systems and the abrasive qualities of the Mars surface material. In addition, rover static charging was investigated and a static discharge system of several fine Tungsten points was developed and fixed to the rover. These experiments and current findings are described herein.

Stevenson, Steven M.

1997-01-01

186

Coral reef hydrogeology  

SciTech Connect

Knowledge of internal flow velocities and pore water residence time is important in understanding pore water geochemistry, nutrient fluxes at the benthic boundary, reef diagenesis, and fresh water resources in reef islands. Hydrogeologic studies of Pacific and Indian Ocean reef and atoll islands indicate a dual aquifer systems; the major Pleistocene aquifer has hydraulic conductivities on the order of 1000 m/d, while the overlying Holocene aquifer of unconsolidated sediments is at least an order of magnitude less permeable. The high permeability in the Pleistocene formation is the result of large voids, both constructional and from subaerial solution during low stands of the sea. Wind, wave and tide induced head differences ranging from a few centimeters to several tens of centimeters provide the driving force for internal flow. Pore water residence times and geochemistry will vary greatly, depending on whether the water is in a major flow channel or in more restricted pores. Studies of both submerged reefs and atoll islands give bulk pore water residence times on the order of months to a few years. Chemical analyses of pore water indicate that both carbonate solution and precipitation are taking place, which will alter porosity and permeability with time. The dual aquifer model also suggests that the Ghyben-Herzberg lens approach to reef island fresh water resources is inaccurate and can lead to a gross overestimation of the potable resource. 18 refs., 5 figs.

Buddemeier, R.W.; Oberdorfer, J.A.

1985-05-21

187

Feedbacks Between Wave Energy And Declining Coral Reef Structure: Implications For Coastal Morphodynamics  

NASA Astrophysics Data System (ADS)

The incident wave energy dissipated by the structural complexity and bottom roughness of coral reef ecosystems, and the carbonate sediment produced by framework-building corals, provide natural shoreline protection and nourishment, respectively. Globally, coral reef ecosystems are in decline as a result of ocean warming and acidification, which is exacerbated by chronic regional stressors such as pollution and disease. As a consequence of declining reef health, many reef ecosystems are experiencing reduced coral cover and shifts to dominance by macroalgae, resulting in a loss of rugosity and thus hydrodynamic roughness. As coral reef architecture is compromised and carbonate skeletons are eroded, wave energy dissipation and sediment transport patterns--along with the carbonate sediment budget of the coastal environment--may be altered. Using a Delft3D numerical model of the south-central Molokai, Hawaii, fringing reef, we simulate the effects of changing reef states on wave energy and sediment transport. To determine the temporally-varying effects of biotic and abiotic stressors such as storms and bleaching on the reef structure and carbonate production, we couple Delft3D with CarboLOT, a model that simulates growth and competition of carbonate-producing organisms. CarboLOT is driven by the Lotka-Volterra population ecology equations and niche suitability principles, and accesses the CarboKB database for region-specific, carbonate-producing species information on growth rates, reproduction patterns, habitat suitability, as well as organism geometries. Simulations assess how changing reef states--which alter carbonate sediment production and reef morphology and thus hydrodynamic roughness--impact wave attenuation and sediment transport gradients along reef-fronted beaches. Initial results suggest that along fringing reefs having characteristics similar to the Molokai fringing reef, projected sea level rise will likely outpace coral reef accretion, and the increased residual wave energy transported to the coast may result in the alteration of alongshore sediment transport gradients and substantial changes to coastal morphology.

Grady, A. E.; Jenkins, C. J.; Moore, L. J.; Potts, D. C.; Burgess, P. M.; Storlazzi, C. D.; Elias, E.; Reidenbach, M. A.

2013-12-01

188

MARS PATHFINDER AIR BAG INSTALLATION IN SAEF-2  

NASA Technical Reports Server (NTRS)

In the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2), the Jet Propulsion Laboratory (JPL) team installs air bags on the Mars Pathfinder lander. The four airbags will cushion the lander as it touches down on the Martian surface, protecting the delicate instruments and Surveyor small rover inside the tetrahedral-shaped lander. The Mars Pathfinder is one of two Mars-bound spacecraft being prepared for launch this fall. Liftoff is set for Dec. 2 at the beginning of a 24-day launch period.

1996-01-01

189

Atmosphere structure and meteorology instrument for Mars Pathfinder  

NASA Technical Reports Server (NTRS)

The MESUR Science Definition Team recommended that all MESUR probes, including Pathfinder, carry an ASI/MET experiment, in order that no opportunity be lost to characterize the atmosphere of Mars in passing through it. The experiment was thus included on Pathfinder from the start (February 1992), but on an essentially noninterference basis: It was to make no unusual demands on the spacecraft. A Science Advisory Team was appointed by NASA Headquarters in September 1993 first met on November 3rd to initiate formal science participation, and the level of activity has since been high. The instrument passed its Preliminary Design Review on February 28th.

Seiff, Alvin

1994-01-01

190

Postglacial Fringing-Reef to Barrier-Reef conversion on Tahiti links Darwin's reef types  

PubMed Central

In 1842 Charles Darwin claimed that vertical growth on a subsiding foundation caused fringing reefs to transform into barrier reefs then atolls. Yet historically no transition between reef types has been discovered and they are widely considered to develop independently from antecedent foundations during glacio-eustatic sea-level rise. Here we reconstruct reef development from cores recovered by IODP Expedition 310 to Tahiti, and show that a fringing reef retreated upslope during postglacial sea-level rise and transformed into a barrier reef when it encountered a Pleistocene reef-flat platform. The reef became stranded on the platform edge, creating a lagoon that isolated it from coastal sediment and facilitated a switch to a faster-growing coral assemblage dominated by acroporids. The switch increased the reef's accretion rate, allowing it to keep pace with rising sea level, and transform into a barrier reef. This retreat mechanism not only links Darwin's reef types, but explains the re-occupation of reefs during Pleistocene glacio-eustacy. PMID:24845540

Blanchon, Paul; Granados-Corea, Marian; Abbey, Elizabeth; Braga, Juan C.; Braithwaite, Colin; Kennedy, David M.; Spencer, Tom; Webster, Jody M.; Woodroffe, Colin D.

2014-01-01

191

Postglacial Fringing-Reef to Barrier-Reef conversion on Tahiti links Darwin's reef types  

NASA Astrophysics Data System (ADS)

In 1842 Charles Darwin claimed that vertical growth on a subsiding foundation caused fringing reefs to transform into barrier reefs then atolls. Yet historically no transition between reef types has been discovered and they are widely considered to develop independently from antecedent foundations during glacio-eustatic sea-level rise. Here we reconstruct reef development from cores recovered by IODP Expedition 310 to Tahiti, and show that a fringing reef retreated upslope during postglacial sea-level rise and transformed into a barrier reef when it encountered a Pleistocene reef-flat platform. The reef became stranded on the platform edge, creating a lagoon that isolated it from coastal sediment and facilitated a switch to a faster-growing coral assemblage dominated by acroporids. The switch increased the reef's accretion rate, allowing it to keep pace with rising sea level, and transform into a barrier reef. This retreat mechanism not only links Darwin's reef types, but explains the re-occupation of reefs during Pleistocene glacio-eustacy.

Blanchon, Paul; Granados-Corea, Marian; Abbey, Elizabeth; Braga, Juan C.; Braithwaite, Colin; Kennedy, David M.; Spencer, Tom; Webster, Jody M.; Woodroffe, Colin D.

2014-05-01

192

Postglacial fringing-reef to barrier-reef conversion on Tahiti links Darwin's reef types.  

PubMed

In 1842 Charles Darwin claimed that vertical growth on a subsiding foundation caused fringing reefs to transform into barrier reefs then atolls. Yet historically no transition between reef types has been discovered and they are widely considered to develop independently from antecedent foundations during glacio-eustatic sea-level rise. Here we reconstruct reef development from cores recovered by IODP Expedition 310 to Tahiti, and show that a fringing reef retreated upslope during postglacial sea-level rise and transformed into a barrier reef when it encountered a Pleistocene reef-flat platform. The reef became stranded on the platform edge, creating a lagoon that isolated it from coastal sediment and facilitated a switch to a faster-growing coral assemblage dominated by acroporids. The switch increased the reef's accretion rate, allowing it to keep pace with rising sea level, and transform into a barrier reef. This retreat mechanism not only links Darwin's reef types, but explains the re-occupation of reefs during Pleistocene glacio-eustacy. PMID:24845540

Blanchon, Paul; Granados-Corea, Marian; Abbey, Elizabeth; Braga, Juan C; Braithwaite, Colin; Kennedy, David M; Spencer, Tom; Webster, Jody M; Woodroffe, Colin D

2014-01-01

193

LISA Pathfinder and eLISA news  

NASA Technical Reports Server (NTRS)

Two important gatherings of the space-based gravitational-wave detector community were held in Zurich, Switzerland this past March. The first was a meeting of the Science Working Team for LISA Pathfinder (LPF), a dedicated technology demonstrator mission for a future LISA-like gravitational wave observatory. LPF is entering an extremely exciting phase with launch less than 15 months away. All flight components for both the European science payload, known as the LISA Technology Package (LTP), and the NASA science payload, known as the Space Technology 7 Disturbance Reduction System (ST7-DRS), have been delivered and are undergoing integration. The final flight component for the spacecraft bus, a cold-gas thruster based on the successful GAIA design, will be delivered later this year. Current focus is on completing integration of the science payload (see Figures 1 and 2) and preparation for operations and data analysis. After a launch in Summer 2015, LPF will take approximately 90 days to reach its operational orbit around the Earth-Sun Lagrange point (L1), where it will begin science operations. After 90 days of LTP operations followed by 90 days of DRS operations, LPF will have completed its prime mission of paving the way for a space-based observatory of gravitational waves in the milliHertz band. Immediately following the meeting of the LPF team, the eLISA consortium held its third progress meeting. The consortium (www.elisascience.org) is the organizing body of the European space-based gravitational-wave community, and it was responsible for the "The Gravitational Universe" whitepaper that resulted in the November 2013 election of a gravitational-wave science theme for ESA's Cosmic Visions L3 opportunity. In preparation for an L3 mission concept call, which is expected later this decade, and for launch in the mid 2030s, the eLISA consortium members are coordinating technology development and mission study activities which will build on the LPF results. The final mission concept is expected to include some international (non-European) contributions, and NASA has expressed an interest in participating in this ground-breaking mission. The US research community supports such a collaboration, or any other mission scenario that achieves the high-priority science of a space-based gravitational-wave observatory at the earliest possible date.

Thorpe, James Ira; Mueller, Guido

2014-01-01

194

Future launcher demonstrator. Challenge and pathfinder  

NASA Astrophysics Data System (ADS)

For future and advanced launch vehicles emphasis is focused on single-stage-to-orbit (SSTO) concepts and on completely reusable versions with the goal to reduce the recurrent launch cost, to improve the mission success probability and also safety for the space transportation of economically attractive payloads into Low Earth Orbit. Both issues, the SSTO launcher and the low cost reusability are extremely challenging and cannot be proven by studies and on-ground tests alone. In-flight demonstration tests are required to verify the assumptions and the new technologies, and to justify the new launcher-and operations-concepts. Because a number of SSTO launch vehicles are currently under discussion in terms of configurations and concepts such as winged vehicles for vertical or horizontal launch and landing (from ground or a flying platform), or wingless vehicles for vertical take-off and landing, and also in terms of propulsion (pure rockets or a combination of air breathing and rocket engines), an experimental demonstrator vehicle appears necessary in order to serve as a pathfinder in this area of multiple challenges. A suborbital Reusable Rocket Launcher Demonstrator (RRLD) has been studied recently by a European industrial team for ESA. This is a multipurpose, evolutionary demonstrator, conceived around a modular approach of incremental improvements of subsystems and materials, to achieve a better propellant mass fraction i.e. a better performance, and specifically for the accomplishment of an incremental flight test programme. While the RRLD basic test programme will acquire knowledge about hypersonic flight, re-entry and landing of a cryogenic rocket propelled launcher — and the low cost reusability (short turnaround on ground) in the utilization programme beyond basic testing, the RRLD will serve as a test bed for generic testing of technologies required for the realization of an SSTO launcher. This paper will present the results of the European RRLD study which proposes a winged suborbital rocket launcher operations & technology demonstrator for vertical take-off and horizontal landing — using primarily conventional technology and materials as a first step towards the challenging goal of a reusable SSTO ETO launch vehicle.

Kleinau, W.; Guerra, L.; Parkinson, R. C.; Lieberherr, J. F.

1996-02-01

195

The CLOUDSAT Experiment: A NASA Pathfinder Mission  

NASA Astrophysics Data System (ADS)

CloudSat will be the first spaceborne deployment of a 94-GHz cloud profiling radar. The mission is a partnership between NASA, Colorado State University, the Canadian Space Agency (CSA), the US Air Force (USAF), and the US Department of Energy's Atmospheric Radiation Measurements (ARM) Program. The spacecraft will be launched in 2004 and will fly in on-orbit formation with the CALIPSO spacecraft and the EOS-Aqua spacecraft, providing a suite of measurements for cloud and aerosol studies. The CloudSat experiment promotes the optimal use of multi-sensor data to produce new pathfinding knowledge that will advance our understanding of the participation of clouds and the hydrological cycle in the Earth climate system. The vertical profile of cloud properties provided by CloudSat fills a critical gap in the investigation of feedback mechanisms linking clouds to climate. Measuring the vertical profile of cloud properties is best addressed by a combination of active and passive instruments, and this will be achieved by combining the radar data of CloudSat with active and passive data from other sensors of the constellation. CloudSat will also provide the first real estimate of the mass of water and ice in the atmosphere and the proportion of this water and ice that falls as precipitation. The CloudSat Science Team is an international partnership, with members from USA, Canada, Japan and Europe having expertise in cloud radar design and observations, cloud and radiation research, and NWP, GCM and cloud modeling. Validation will rely heavily on the systematic measurement programs of ARM as well as systematic measurements planned for selected sites in Europe and Japan. Validation will also benefit from the aircraft radar measurement activities of USA, Canada, Japan and Europe, from the measurement capabilities at number of universities, and from cloud field-campaign activities representing targets of opportunity planned in the coming years, including field campaigns associated with the CALIPSO and AQUA missions. Further information on the CloudSat mission may be obtained from the author or by accessing the CloudSat Home Page at http://cloudsat.atmos.colostate.edu.

Stephens, G.; Vane, D.

2003-04-01

196

Gray's Reef Research  

NSDL National Science Digital Library

Provides a sampling of research projects conducted at the Gray's Reef National Marine Sanctuary off Georgia's Sapelo Island. Projects range from geology to trawling impacts on the seafloor, estimating fish populations by video transect, Sanctuary monitoring using data buoys, sidescan sonar and other technologies. Examples of current projects: conducting a study on the movement patterns of fish in the area; efforts to understand the roles of "choices" fishes might make in their behaviors, and its impact on diversity of species found in reef fish communities and a study designed to inventory the invertebrates and fish communities and analyze how those communities are impacted by fishing activities. Appropriate for grades 9 and up.

197

Sewage impacts coral reefs at multiple levels of ecological organization.  

PubMed

Against a backdrop of rising sea temperatures and ocean acidification which pose global threats to coral reefs, excess nutrients and turbidity continue to be significant stressors at regional and local scales. Because interventions usually require local data on pollution impacts, we measured ecological responses to sewage discharges in Surin Marine Park, Thailand. Wastewater disposal significantly increased inorganic nutrients and turbidity levels, and this degradation in water quality resulted in substantial ecological shifts in the form of (i) increased macroalgal density and species richness, (ii) lower cover of hard corals, and (iii) significant declines in fish abundance. Thus, the effects of nutrient pollution and turbidity can cascade across several levels of ecological organization to change key properties of the benthos and fish on coral reefs. Maintenance or restoration of ecological reef health requires improved wastewater management and run-off control for reefs to deliver their valuable ecosystems services. PMID:19515390

Reopanichkul, Pasinee; Schlacher, Thomas A; Carter, R W; Worachananant, Suchai

2009-09-01

198

Status and progress in coral reef disease research.  

PubMed

Recent findings on the ecology, etiology and pathology of coral pathogens, host resistance mechanisms, previously unknown disease/syndromes and the global nature of coral reef diseases have increased our concern about the health and future of coral reef communities. Much of what has been discovered in the past 4 years is presented in this special issue. Among the significant findings, the role that various Vibrio species play in coral disease and health, the composition of the 'normal microbiota' of corals, and the possible role of viruses in the disease process are important additions to our knowledge. New information concerning disease resistance and vectors, variation in pathogen composition for both fungal diseases of gorgonians and black band disease across oceans, environmental effects on disease susceptibility and resistance, and temporal and spatial disease variations among different coral species is presented in a number of papers. While the Caribbean may still be the 'disease hot spot' for coral reefs, it is now clear that diseases of coral reef organisms have become a global threat to coral reefs and a major cause of reef deterioration. PMID:16703761

Weil, Ernesto; Smith, Garriet; Gil-Agudelo, Diego L

2006-03-23

199

Coral reef resilience through biodiversity  

USGS Publications Warehouse

Irrefutable evidence of coral reef degradation worldwide and increasing pressure from rising seawater temperatures and ocean acidification associated with climate change have led to a focus on reef resilience and a call to “manage” coral reefs for resilience. Ideally, global action to reduce emission of carbon dioxide and other greenhouse gases will be accompanied by local action. Effective management requires reduction of local stressors, identification of the characteristics of resilient reefs, and design of marine protected area networks that include potentially resilient reefs. Future research is needed on how stressors interact, on how climate change will affect corals, fish, and other reef organisms as well as overall biodiversity, and on basic ecological processes such as connectivity. Not all reef species and reefs will respond similarly to local and global stressors. Because reef-building corals and other organisms have some potential to adapt to environmental changes, coral reefs will likely persist in spite of the unprecedented combination of stressors currently affecting them. The biodiversity of coral reefs is the basis for their remarkable beauty and for the benefits they provide to society. The extraordinary complexity of these ecosystems makes it both more difficult to predict their future and more likely they will have a future.

Rogers, Caroline S.

2013-01-01

200

The evolution of reef communities  

SciTech Connect

This book discusses the composition, structure, occurrence, and changes in reefs during the past 2 billion years. It emphasizes the functional roles of major groups (guilds) of reef-building, reef-destroying, and reed-dwelling organisms in the most complex of all marine communities. A structural model, based on modern reef guilds, is developed. Then the functional roles of each major reef-building higher biologic taxon (algae, sponges, coral, etc.) is determined, and, on this basis, each such taxon is assigned to a reef community guild. Next, the authors traces the geologic history and guild assignment of each major taxon through geologic time. The final chapter establishes a succession of ten major reef community types, and considers their extinction and recovery in the light of modern theories of cosmic and earthly events.

Fagerstrom, J.A.

1987-01-01

201

Rapid survey protocol that provides dynamic information on reef condition to managers of the Great Barrier Reef.  

PubMed

Managing to support coral reef resilience as the climate changes requires strategic and responsive actions that reduce anthropogenic stress. Managers can only target and tailor these actions if they regularly receive information on system condition and impact severity. In large coral reef areas like the Great Barrier Reef Marine Park (GBRMP), acquiring condition and impact data with good spatial and temporal coverage requires using a large network of observers. Here, we describe the result of ~10 years of evolving and refining participatory monitoring programs used in the GBR that have rangers, tourism operators and members of the public as observers. Participants complete Reef Health and Impact Surveys (RHIS) using a protocol that meets coral reef managers' needs for up-to-date information on the following: benthic community composition, reef condition and impacts including coral diseases, damage, predation and the presence of rubbish. Training programs ensure that the information gathered is sufficiently precise to inform management decisions. Participants regularly report because the demands of the survey methodology have been matched to their time availability. Undertaking the RHIS protocol we describe involves three ~20 min surveys at each site. Participants enter data into an online data management system that can create reports for managers and participants within minutes of data being submitted. Since 2009, 211 participants have completed a total of more than 10,415 surveys at more than 625 different reefs. The two-way exchange of information between managers and participants increases the capacity to manage reefs adaptively, meets education and outreach objectives and can increase stewardship. The general approach used and the survey methodology are both sufficiently adaptable to be used in all reef regions. PMID:25179944

Beeden, R J; Turner, M A; Dryden, J; Merida, F; Goudkamp, K; Malone, C; Marshall, P A; Birtles, A; Maynard, J A

2014-12-01

202

Coral records of reef-water pH across the central Great Barrier Reef, Australia: assessing the influence of river runoff on inshore reefs  

NASA Astrophysics Data System (ADS)

The boron isotopic (?11Bcarb) compositions of long-lived Porites coral are used to reconstruct reef-water pH across the central Great Barrier Reef (GBR) and assess the impact of river runoff on inshore reefs. For the period from 1940 to 2009, corals from both inner as well as mid-shelf sites exhibit the same overall decrease in ?11Bcarb of 0.086 ± 0.033‰ per decade, equivalent to a~decline in seawater pH (pHsw) of ~ 0.017 ± 0.007 pH units per decade. This decline is consistent with the long-term effects of ocean acidification based on estimates of CO2 uptake by surface waters due to rising atmospheric levels. We also find that compared to the mid-shelf corals, the ?11Bcarb compositions for inner shelf corals subject to river discharge events, have higher and more variable values and hence higher inferred pHsw values. These higher ?11Bcarb values for inner-shelf corals are particularly evident during wet years, despite river waters having lower pH. The main effect of river discharge on reef-water carbonate chemistry thus appears to be from higher nutrients driving increased phytoplankton productivity, resulting in the drawdown of pCO2 and increase in pHsw. Increased primary production therefore has the potential to counter the more transient effects of low pH river water (pHrw) discharged into near-shore environments. Importantly however, inshore reefs also show a consistent pattern of sharply declining coral growth that coincides with periods of high river discharge. This occurs despite these reefs having higher pHsw values and hence higher seawater aragonite saturation states, demonstrating the over-riding importance of local reef-water quality on coral reef health.

D'Olivo, J. P.; McCulloch, M. T.; Eggins, S. M.; Trotter, J.

2014-07-01

203

Coral records of reef-water pH across the central Great Barrier Reef, Australia: assessing the influence of river runoff on inshore reefs  

NASA Astrophysics Data System (ADS)

The boron isotopic (?11Bcarb) compositions of long-lived Porites coral are used to reconstruct reef-water pH across the central Great Barrier Reef (GBR) and assess the impact of river runoff on inshore reefs. For the period from 1940 to 2009, corals from both inner- and mid-shelf sites exhibit the same overall decrease in ?11Bcarb of 0.086 ± 0.033‰ per decade, equivalent to a decline in seawater pH (pHsw) of ~0.017 ± 0.007 pH units per decade. This decline is consistent with the long-term effects of ocean acidification based on estimates of CO2 uptake by surface waters due to rising atmospheric levels. We also find that, compared to the mid-shelf corals, the ?11Bcarb compositions of inner-shelf corals subject to river discharge events have higher and more variable values, and hence higher inferred pHsw values. These higher ?11Bcarb values of inner-shelf corals are particularly evident during wet years, despite river waters having lower pH. The main effect of river discharge on reef-water carbonate chemistry thus appears to be from reduced aragonite saturation state and higher nutrients driving increased phytoplankton productivity, resulting in the drawdown of pCO2 and increase in pHsw. Increased primary production therefore has the potential to counter the more transient effects of low-pH river water (pHrw) discharged into near-shore environments. Importantly, however, inshore reefs also show a consistent pattern of sharply declining coral growth that coincides with periods of high river discharge. This occurs despite these reefs having higher pHsw, demonstrating the overriding importance of local reef-water quality and reduced aragonite saturation state on coral reef health.

D'Olivo, J. P.; McCulloch, M. T.; Eggins, S. M.; Trotter, J.

2015-02-01

204

Reef talus: A popular misconception  

NASA Astrophysics Data System (ADS)

Reef fronts have traditionally been regarded as comprising debris derived by contemporaneous erosion of 'the reef'. However, evidence from wave transport indicates that on present-day reefs the bulk of the debris generated in this way accumulates in the back-reef area, with only finer-grained sediment carried off-reef by retreating flows or by overwash. Nevertheless, in contrast to this observation, 'fore-reef' debris slopes are commonly considered "characteristic" of Phanerozoic reefs. This apparent error reflects the conflation of processes defining contemporary growth and accretion of the reef, and the corresponding long-term accretion of the carbonate platform on which it rests. Present-day reefs are commonly (although not exclusively) additions to long-lived carbonate platforms. Growth of the latter is intermittent and has been moderated by changes in sea-level that, for recent reefs, have been on time scales of less than 100 ka. During low sea-level stands, growth ceases or is translated downslope and earlier deposits are subject to lithification and subaerial erosion. Similar changes are applied on a larger scale to the aggrading growth of carbonate platforms, but the bulk accretion of these includes quite different processes and reflects far longer timescales. During low sea-level stands, the margins of platforms commonly become unstable, with instability reflected in slope failure and in the shedding of blocks, ranging from metres to kilometres in diameter, associated with the generation of debris flows and turbidites. It is argued that these are the materials that are commonly described as 'reef talus' in ancient structures, although their formation is largely independent of any contemporary reef growth. Difficulties arise where 'the reef' and 'the platform' are treated as a single functional entity. It is important to recognize the conceptual distinction between them, 'reef talus' is a misleading description of the debris predominantly generated by platform erosion and slope failure.

Braithwaite, Colin J. R.

2014-01-01

205

Pathfinder: XQuery--The Relational Way Peter Boncz1  

E-print Network

Pathfinder: XQuery--The Relational Way Peter Boncz1 Torsten Grust2 Maurice van Keulen3 Stefan Manegold1 Jan Rittinger1,4, Jens Teubner2 1 CWI Amsterdam, The Netherlands 2 Technische Universit¨at M¨unchen, Germany {boncz,manegold}@cwi.nl {torsten.grust,jens.teubner}@in.tum.de 3 University of Twente

Reiterer, Harald

206

Coordinate Map of Rocks at Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

Mars-local-level (LL frame) coordinate map of rocks counted at the Mars Pathfinder landing site. Positions, apparent diameters (D), and heights (H) were measured to the nearest centimeter in the Mars map virtual reality environment constructed from the 'Monster Pan'

1997-01-01

207

The LISA Pathfinder interferometry---hardware and system testing  

Microsoft Academic Search

Preparations for the LISA Pathfinder mission have reached an exciting stage. Tests of the engineering model (EM) of the optical metrology system have recently been completed at the Albert Einstein Institute, Hannover, and flight model tests are now underway. Significantly, they represent the first complete integration and testing of the space-qualified hardware and are the first tests on an optical

H. Audley; K. Danzmann; A. García Marín; G. Heinzel; A. Monsky; M. Nofrarias; F. Steier; D. Gerardi; R. Gerndt; G. Hechenblaikner; U. Johann; P. Luetzow-Wentzky; V. Wand; F. Antonucci; M. Armano; G. Auger; M. Benedetti; P. Binetruy; C. Boatella; J. Bogenstahl; D. Bortoluzzi; P. Bosetti; M. Caleno; A. Cavalleri; M. Cesa; M. Chmeissani; G. Ciani; A. Conchillo; G. Congedo; I. Cristofolini; M. Cruise; F. De Marchi; M. Diaz-Aguilo; I. Diepholz; G. Dixon; R. Dolesi; J. Fauste; L. Ferraioli; D. Fertin; W. Fichter; E. Fitzsimons; M. Freschi; C. García Marirrodriga; L. Gesa; F. Gibert; D. Giardini; C. Grimani; A. Grynagier; B. Guillaume; F. Guzmán; I. Harrison; M. Hewitson; D. Hollington; J. Hough; D. Hoyland; M. Hueller; J. Huesler; O. Jeannin; O. Jennrich; P. Jetzer; B. Johlander; C. Killow; X. Llamas; I. Lloro; A. Lobo; R. Maarschalkerweerd; S. Madden; D. Mance; I. Mateos; P. W. McNamara; J. Mendes; E. Mitchell; D. Nicolini; D. Nicolodi; F. Pedersen; M. Perreur-Lloyd; A. Perreca; E. Plagnol; P. Prat; G. D. Racca; B. Rais; J. Ramos-Castro; J. Reiche; J. A. Romera Perez; D. Robertson; H. Rozemeijer; J. Sanjuan; M. Schulte; D. Shaul; L. Stagnaro; S. Strandmoe; T. J. Sumner; A. Taylor; D. Texier; C. Trenkel; D. Tombolato; S. Vitale; G. Wanner; H. Ward; S. Waschke; P. Wass; W. J. Weber; P. Zweifel

2011-01-01

208

Experiences with operations and autonomy of the Mars Pathfinder Microrover  

Microsoft Academic Search

The Microrover Flight Experiment (MFEX) is a NASA OACT (Office of Advanced Concepts and Technology) flight experiment which, integrated with the Mars Pathfinder (MPF) lander and spacecraft system, landed on Mars on July 4, 1997. In the succeeding 30 sols (1 sol=1 Martian day), the Sojourner microrover accomplished all of its primary and extended mission objectives. After completion of the

A. H. Mishkin; J. C. Morrison; T. T. Nguyen; H. W. Stone; B. K. Cooper; B. H. Wilcox

1998-01-01

209

A Pathfinder for Animal Research and Animal Rights.  

ERIC Educational Resources Information Center

This pathfinder was originally prepared for "Biomedical Research and Animal Rights," a session sponsored by the Veterinary Medical Libraries and Research Libraries Sections of the Medical Library Association. Current resources are described, from bibliographies to electronic bulletin boards, which relate to the issue of laboratory animal welfare…

Anderson, David C.

1992-01-01

210

Pathfinder wing tip video at 50,000 feet  

NASA Technical Reports Server (NTRS)

In this clip, the Pathfinder's wing camera shows the view from 50,000 feet. Below is the reddish-brown desert, with the curvature of the Earth visible. Above this is a haze, which blends into the blue-black sky. The vehicle is more than 10,000 feet above an airliner's normal altitude.

1995-01-01

211

CRUISE REPORT USNS Pathfinder (T-AGS-60)  

E-print Network

CRUISE REPORT USNS Pathfinder (T-AGS-60) U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the Northeast US Atlantic continental margin: Legs 4 and 5 CRUISES PF05-1 and 2 April........................................................................................................21 Table 1, Cruise Statistics

New Hampshire, University of

212

Visualizing Evolving Networks: Minimum Spanning Trees versus Pathfinder Networks  

Microsoft Academic Search

Network evolution is a ubiquitous phenomenon in a wide variety of complex systems. In fields such as statistical mechanics, there has been increasingly widespread interest in modeling the growth of complex networks. In this article, we compare two network visualization techniques, minimum spanning trees (MSTs) and Pathfinder networks (PFNETs), and their visualizations of co - citation networks of scientific publications.

Chaomei Chen; Steven Morris

2003-01-01

213

LISA Pathfinder: the geodesy explorer testing alternative theories of gravity  

NASA Astrophysics Data System (ADS)

The LISA Pathfinder spacecraft by ESA is on schedule to fly by autumn 2015. Implementing a high precision free-fall in-flight system near a Lagrangian point, the mission relies on technologies never used before in space environments and crucial to gravitational waves observatories. The core instrument configuration makes LISA Pathfinder a gradiometer of unprecedented sensitivity. The designated orbit places it in position to further cruise through a volume of space where Newtonian pulls compensate and the Newtonian acceleration is close to zero. In the global picture that sees several dark matter/energy models and many theories at work to match observations, the free-fall specialist LISA Pathfinder can directly explore gravity at its alleged depart from the Newtonian regime, realizing a null dynamical test so far missing between astrophysical measurements and planetary tests. We will explicitly consider MOND theories as a test canvas and show that without further modifications the LISA Pathfinder instrument could sample several scales of the Newtonian-MONDian regime. We shall highlight the science case, the current experiment, the measurement design and the related data analysis.

Armano, Michele

214

Pathfinders for Four Directions: An Indigenous Educational Model.  

ERIC Educational Resources Information Center

The Four Directions Project, administered by the Pueblo of Laguna Department of Education, is a 5-year federally-funded technology innovation grant that aims to help Native people and their educators develop culturally relevant curricula through technology. This report includes the full text of 45 "pathfinders" designed by students in the Graduate…

Roy, Loriene, Comp.

215

The Cornell Center for Materials Research (CCMR) is the pathfinder  

E-print Network

for the benefit of all species. Research programs integrate basic, preclinical, and clinical investigationsThe Cornell Center for Materials Research (CCMR) is the pathfinder for interdisciplinary centers in research as well as complemen- tary outreach programs. Over the years, the center has remained at the cusp

Danforth, Bryan Nicholas

216

Teacher job satisfaction: lessons from the TSW Pathfinder Project  

Microsoft Academic Search

Government policy assumes that modernization and remodelling will be effective as external intervention mechanisms to improve job satisfaction. Based on data collected as part of the evaluation of the ‘Transforming the School Workforce Pathfinder Project’, an argument is presented here which suggests that internal management models may be more effective in improving teacher job satisfaction. By comparing the responses of

Graham Butt; Ann Lance; Antony Fielding; Helen Gunter; Steve Rayner; Hywel Thomas

2005-01-01

217

Sedimentary geomorphology of the Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

The first landing on Mars in over 20 years will take place July 4, 1997, near te mouth of the Ares Vallis outflow channel located in southeastern Chryse Planitia. Mars Pathfinder, unlike Viking 1, is expected to land on a surface that has a distinct and unambiguous fluvial signature.

Rice, James W., Jr.; Parker, Timothy Jay

1997-01-01

218

Forecasting decadal changes in sea surface temperatures and coral bleaching within a Caribbean coral reef  

E-print Network

REPORT Forecasting decadal changes in sea surface temperatures and coral bleaching within affect the health of coral reefs by increasing rates of coral bleaching, how changes to atmospheric Á Coral reefs Á Sea surface temperature Á Coral bleaching Introduction A primary direct consequence

Reidenbach, Matthew A.

219

Create a Coral Reef  

NSDL National Science Digital Library

Educator Amy O'Donnell from the American Museum of Natural History guides learners to create a diorama of a coral reef. Learners will use craft skills to transform household materials into simulated brain coral, sea fans, sea anemones, and a sponge. This resource contains background information about coral and the use of dioramas in museums. Also includes extension ideas.

2012-06-26

220

Coral Reef Biological Criteria  

EPA Science Inventory

Coral reefs worldwide are experiencing decline from a variety of stressors. Some important stressors are land-based sources of pollution and human activities in the coastal zone. However, few tools are available to offset the impact of these stressors. The Clean Water Act (CWA...

221

CORAL REEF BIOCRITERIA  

EPA Science Inventory

Coral reefs worldwide are experiencing the greatest decline of their known existence and few tools are available to offset the growing impacts of human coastal and watershed activities. Biocriteria are a potentially effective means to evaluate and restore impaired waters, but are...

222

Reefs since Columbus  

Microsoft Academic Search

History shows that Caribbean coastal ecosystems were severely degraded long before ecologists began to study them. Large vertebrates such as the green turtle, hawksbill turtle, manatee and extinct Caribbean monk seal were decimated by about 1800 in the central and northern Caribbean, and by 1990 elsewhere. Subsistence over-fishing subsequently decimated reef fish populations. Local fisheries accounted for a small fraction

J. B. C. Jackson

1997-01-01

223

Capitol Reef Petroglyphs  

USGS Multimedia Gallery

From about 300-1300 CE, ancestors of the Hopi Tribe, Pueblo of Zuni, and Paiute Tribe lived in Capitol Reef. They are known by various names-archeologists call them the Fremont Culture; the Hopi Tribe calls them the Hisatsinom, or the

224

Castle in Capitol Reef  

USGS Multimedia Gallery

A view of the Castle, a prominent sandstone formation in Capitol Reef National Park. This area, known as the Fruita, is made up of three primary layers. The bottom sandstone layer is known as the Moenkopi Formation and is about 245 million years old. The middle gray-green layer is known as the Chinl...

225

Capitol Reef's Castle  

USGS Multimedia Gallery

A view of the Castle, a prominent sandstone formation in Capitol Reef National Park. This area, known as the Fruita, is made up of three primary layers. The bottom sandstone layer is known as the Moenkopi Formation and is about 245 million years old. The middle gray-green layer is known as the Chinl...

226

Petroglyphs in Captiol Reef  

USGS Multimedia Gallery

From about 300-1300 CE, ancestors of the Hopi Tribe, Pueblo of Zuni, and Paiute Tribe lived in Capitol Reef. They are known by various names-archeologists call them the Fremont Culture; the Hopi Tribe calls them the Hisatsinom, or the

227

Rivers, runoff, and reefs  

USGS Publications Warehouse

The role of terrigenous sediment in controlling the occurrence of coral reef ecosystems is qualitatively understood and has been studied at local scales, but has not been systematically evaluated on a global-to-regional scale. Current concerns about degradation of reef environments and alteration of the hydrologic and sediment cycles place the issue at a focal point of multiple environmental concerns. We use a geospatial clustering of a coastal zone database of river and local runoff identified with 0.5?? grid cells to identify areas of high potential runoff effects, and combine this with a database of reported coral reef locations. Coastal cells with high runoff values are much less likely to contain reefs than low runoff cells and GIS buffer analysis demonstrates that this inhibition extends to offshore ocean cells as well. This analysis does not uniquely define the effects of sediment, since salinity, nutrients, and contaminants are potentially confounding variables also associated with runoff. However, sediment effects are likely to be a major factor and a basis is provided for extending the study to higher resolution with more specific variables. ?? 2003 Elsevier B.V. All rights reserved.

McLaughlin, C.J.; Smith, C.A.; Buddemeier, R.W.; Bartley, J.D.; Maxwell, B.A.

2003-01-01

228

Reef Fishes of Saba Bank, Netherlands Antilles: Assemblage Structure across a Gradient of Habitat Types  

PubMed Central

Saba Bank is a 2,200 km2 submerged carbonate platform in the northeastern Caribbean Sea off Saba Island, Netherlands Antilles. The presence of reef-like geomorphic features and significant shelf edge coral development on Saba Bank have led to the conclusion that it is an actively growing, though wholly submerged, coral reef atoll. However, little information exists on the composition of benthic communities or associated reef fish assemblages of Saba Bank. We selected a 40 km2 area of the bank for an exploratory study. Habitat and reef fish assemblages were investigated in five shallow-water benthic habitat types that form a gradient from Saba Bank shelf edge to lagoon. Significant coral cover was restricted to fore reef habitat (average cover 11.5%) and outer reef flat habitat (2.4%) and declined to near zero in habitats of the central lagoon zone. Macroalgae dominated benthic cover in all habitats (average cover: 32.5 – 48.1%) but dominant algal genera differed among habitats. A total of 97 fish species were recorded. The composition of Saba Bank fish assemblages differed among habitat types. Highest fish density and diversity occurred in the outer reef flat, fore reef and inner reef flat habitats. Biomass estimates for commercially valued species in the reef zone (fore reef and reef flat habitats) ranged between 52 and 83 g/m2. The composition of Saba Bank fish assemblages reflects the absence of important nursery habitats, as well as the effects of past fishing. The relatively high abundance of large predatory fish (i.e. groupers and sharks), which is generally considered an indicator of good ecosystem health for tropical reef systems, shows that an intact trophic network is still present on Saba Bank. PMID:20502637

Toller, Wes; Debrot, Adolphe O.; Vermeij, Mark J. A.; Hoetjes, Paul C.

2010-01-01

229

Miocene reefs in western Mediterranean  

SciTech Connect

Coral reefs were particularly abundant and well developed during the late Tortonian and Messinian in southeastern Spain, the Balearic Islands, Italy, Sicily, Algeria, and Morocco. These reefs occurred just before and during the deposition of the thick Messinian evaporite units in the basinal areas and disappeared completely from Mediteranean during the early Pliocene. Most of the coral reefs are fringing terrigenous coastal fan complexes with very small lagoons and show progradation of less than 2 km. Some of the reefs occur on, or are intercalated with, Neogene volcanics or Messinian evaporites. Barrier-reef complexes are less common, have extensive lagoons behind them, and show complex progradational geometries more than 10 km wide. Excellent outcrops allow detailed reconstruction of paleogeography and sea level changes. Progradation predominated during phases of relative sea level drops and stillsands, while significant retrogradation occurred during sea level rises. The coral reef wall framework is commonly less than 20 m thick and is dominated by Porites and, locally, Tarbellastrae. Older Miocene reefs are less well developed, but show greater diversity of corals and reef organisms. Younger Miocene reef complexes occurring in open ocean settings are formed by only one branching coral genus (Porites or, locally, Tarbellastraea) with branching colonies up to 7 m high. Halimeda sands are particularly abundant in the upper reef slopes with occasional intercalations of red algae pavements that most likely coincide with episodes of terrigenous influx.

Esteban, M.

1988-01-01

230

Ecological intereactions of reef building corals  

EPA Science Inventory

Coral reefs are very important marine ecosystems because they support tremendous biodiversity and reefs are critical economic resources many coastal nations. Tropical reef structures are largely built by stony corals. This presentation provides background on basic coral biology t...

231

Coral Reef Connections-Ecological Relationships Among Reef Creatures  

NSDL National Science Digital Library

In this interactive dive through Australia's Great Barrier Reef, students will discover relationships that have evolved between the resident organisms. Some are predators and prey; others compete for space, food, or mates; and still others are dependent or codependent on each other. Students select one of four reef zones, then click on a type of relationship, predation and parasitism, competition or commensalism and mutualism to learn more about these relationships among reef creatures.

WGBH

2011-10-24

232

Coral Reef Protection: A Watershed Approach  

NSDL National Science Digital Library

EPA's home page on coral reef protection activities, including The International Coral Reef Initiative, and The Coral Reef Symposium. A tremendous resource for educators interested in coral reef basics through advanced topics such as coral reef ecology and legislation. Site includes peer-reviewed journal articles, factsheets, maps, and video. The Links section is packed with extensive coral reef information sites covering international and domestic initiatives, research, and even a section for kids and teachers.

233

An observational heat budget analysis of a coral reef, Heron Reef, Great Barrier Reef, Australia  

NASA Astrophysics Data System (ADS)

Measurements of the surface energy balance, the structure and evolution of the convective atmospheric reef layer (CARL), and local meteorology and hydrodynamics were made during June 2009 and February 2010 at Heron Reef, Australia, to establish the relative partitioning of heating within the water and atmosphere. Horizontal advection was shown to moderate temperature in the CARL and the water, having a cooling influence on the atmosphere, and providing an additional source or sink of energy to the water overlying the reef, depending on tide. The key driver of atmospheric heating was surface sensible heat flux, while heating of the reef water was primarily due to solar radiation, and thermal conduction and convection from the reef substrate. Heating and cooling processes were more defined during winter due to higher sensible and latent heat fluxes and strong diurnal evolution of the CARL. Sudden increases in water temperature were associated with inundation of warmer oceanic water during the flood tide, particularly in winter due to enhanced nocturnal cooling of water overlying the reef. Similarly, cooling of the water over the reef occurred during the ebb tide as heat was transported off the reef to the surrounding ocean. While these results are the first to shed light on the heat budget of a coral reef and overlying CARL, longer-term, systematic measurements of reef thermal budgets are needed under a range of meteorological and hydrodynamic conditions, and across various reef types to elucidate the influence on larger-scale oceanic and atmospheric processes. This is essential for understanding the role of coral reefs in tropical and sub-tropical meteorology; the physical processes that take place during coral bleaching events, and coral and algal community dynamics on coral reefs.

MacKellar, Mellissa C.; McGowan, Hamish A.; Phinn, Stuart R.

2013-03-01

234

Ecotourism: The Great Barrier Reef  

NSDL National Science Digital Library

Working with your partner, pretend you are employed with an ecotourism company. Your goal is to convince the Australian government that you would be the most qualified team to give ecotours of the Great Barrier Reef. Create a brochure to demonstrate your knowledge and ability. To get the job as ecotour guides, you will need to know a lot about the reef, and about how to visit it in an environmentally sound way. Start your research by filling out the Research Outline. The following websites will be most useful in finding the needed information: FACT SHEET ON CORAL OF THE GREAT BARRIER REEF Great Barrier Reef Marine Park Authority National Geographic: Great Barrier Reef Students and Teachers Coastal Watershed Factsheets Coral Reefs and Your Coastal Watershed Once you ...

Mrs. Wheeler

2010-05-18

235

International Society for Reef Studies  

NSDL National Science Digital Library

Located within the Florida Institute of Technology, the International Society for Reef Studies (ISRS) was founded in 1980, and is designed to disseminate its findings on both living and fossil coral reefs to fellow scholars around the globe and the general public. Before delving into the main site, visitors will want to look through the ISRS in-house publication "Reef Encounters" to get a sense of the various projects the organization is currently working on, and of course, to read brief summaries of its research findings. Of course, for those who already are passionate about coral reefs, there is also a link to sign up for the NOAA "Coral List" forum. The resources section of the site is another good place to look for outside Web resources on other coral reef societies, marine laboratories, and government sites that contain materials on coral reefs and marine biology.

236

Oceanic Forcing of Coral Reefs  

NASA Astrophysics Data System (ADS)

Although the oceans play a fundamental role in shaping the distribution and function of coral reefs worldwide, a modern understanding of the complex interactions between ocean and reef processes is still only emerging. These dynamics are especially challenging owing to both the broad range of spatial scales (less than a meter to hundreds of kilometers) and the complex physical and biological feedbacks involved. Here, we review recent advances in our understanding of these processes, ranging from the small-scale mechanics of flow around coral communities and their influence on nutrient exchange to larger, reef-scale patterns of wave- and tide-driven circulation and their effects on reef water quality and perceived rates of metabolism. We also examine regional-scale drivers of reefs such as coastal upwelling, internal waves, and extreme disturbances such as cyclones. Our goal is to show how a wide range of ocean-driven processes ultimately shape the growth and metabolism of coral reefs.

Lowe, Ryan J.; Falter, James L.

2015-01-01

237

Oceanic forcing of coral reefs.  

PubMed

Although the oceans play a fundamental role in shaping the distribution and function of coral reefs worldwide, a modern understanding of the complex interactions between ocean and reef processes is still only emerging. These dynamics are especially challenging owing to both the broad range of spatial scales (less than a meter to hundreds of kilometers) and the complex physical and biological feedbacks involved. Here, we review recent advances in our understanding of these processes, ranging from the small-scale mechanics of flow around coral communities and their influence on nutrient exchange to larger, reef-scale patterns of wave- and tide-driven circulation and their effects on reef water quality and perceived rates of metabolism. We also examine regional-scale drivers of reefs such as coastal upwelling, internal waves, and extreme disturbances such as cyclones. Our goal is to show how a wide range of ocean-driven processes ultimately shape the growth and metabolism of coral reefs. PMID:25251270

Lowe, Ryan J; Falter, James L

2015-01-01

238

The Paleoecology of Coral Reefs  

Microsoft Academic Search

\\u000a Reefs are one of the oldest ecosystems in the world, and coral reefs have had a rich and varied history over hundreds of millions\\u000a of years. The long-term history of living reef organisms provides an essential window in which to view a number of fundamental\\u000a evolutionary and ecological processes over extended time frames not available to modern ecology over years

John M. Pandolfi

239

Spatial Resilience of Coral Reefs  

Microsoft Academic Search

There have been several earlier studies that addressed the influence of natural disturbance regimes on coral reefs. Humans\\u000a alter natural disturbance regimes, introduce new stressors, and modify background conditions of reefs. We focus on how coral\\u000a reef ecosystems relate to disturbance in an increasingly human-dominated environment. The concept of ecosystem resilience—that\\u000a is, the capacity of complex systems with multiple stable

Magnus Nyström; Carl Folke

2001-01-01

240

Coral Reefs in Hot Water  

NSDL National Science Digital Library

In this activity, student teams identify the locations of coral reefs around the world, examine infrared satellite images of the Earth, and research the impacts that are threatening the survival of coral reefs. Each team creates a short oral presentation describing the coral reef they have researched. Students then plot on a composite map the locations where coral bleaching is occurring. Student worksheets, a teacher guide, and assessment rubric are included. This activity is part of Coastal Areas: Coral Reefs in Hot Water, part of the lesson series, The Potential Consequences of Climate Variability and Change.

2012-08-03

241

Digital Reef Rugosity Estimates Coral Reef Habitat Complexity  

PubMed Central

Ecological habitats with greater structural complexity contain more species due to increased niche diversity. This is especially apparent on coral reefs where individual coral colonies aggregate to give a reef its morphology, species zonation, and three dimensionality. Structural complexity is classically measured with a reef rugosity index, which is the ratio of a straight line transect to the distance a flexible chain of equal length travels when draped over the reef substrate; yet, other techniques from visual categories to remote sensing have been used to characterize structural complexity at scales from microhabitats to reefscapes. Reef-scale methods either lack quantitative precision or are too time consuming to be routinely practical, while remotely sensed indices are mismatched to the finer scale morphology of coral colonies and reef habitats. In this communication a new digital technique, Digital Reef Rugosity (DRR) is described which utilizes a self-contained water level gauge enabling a diver to quickly and accurately characterize rugosity with non-invasive millimeter scale measurements of coral reef surface height at decimeter intervals along meter scale transects. The precise measurements require very little post-processing and are easily imported into a spreadsheet for statistical analyses and modeling. To assess its applicability we investigated the relationship between DRR and fish community structure at four coral reef sites on Menjangan Island off the northwest corner of Bali, Indonesia and one on mainland Bali to the west of Menjangan Island; our findings show a positive relationship between DRR and fish diversity. Since structural complexity drives key ecological processes on coral reefs, we consider that DRR may become a useful quantitative community-level descriptor to characterize reef complexity. PMID:23437380

Dustan, Phillip; Doherty, Orla; Pardede, Shinta

2013-01-01

242

First light of the LINC-NIRVANA Pathfinder experiment  

NASA Astrophysics Data System (ADS)

The LINC-NIRVANA Pathfinder experiment is a test-bed to verify a very complex sub-system: the Ground-layer Wavefront Sensor, or GWS. Pathfinder will test the GWS in its final working environment and demonstrate on-sky the performance achievable with a multiple natural guide star, ground-layer adaptive optics system with a very wide FoV. The GWS uses up to 12 natural guide stars within a 2.8'-6' annular field of view and drives the LBT adaptive secondary mirror to correct the lower layers of atmospheric turbulence. This paper will trace the path of the instrument on its way to First Light on-sky in November 2013, from its installation on the telescope to the calibrations to its final operation, focusing in particular on opto-mechanical and software aspects and how they lead to the main achieved results.

Bergomi, M.; Viotto, V.; Arcidiacono, C.; Marafatto, L.; Farinato, J.; Baumeister, H.; Bertram, T.; Berwein, J.; Briegel, F.; Conrad, A.; Kittman, F.; Kopon, D.; Hofferbert, R.; Magrin, D.; Radhakrishnan Santhakumari, K. K.; Puglisi, A.; Xompero, M.; Briguglio, R.; Quiros-Pacheco, F.; Herbst, T. M.; Ragazzoni, R.

2014-07-01

243

Interface Generation and Compositional Verification in JavaPathfinder  

NASA Technical Reports Server (NTRS)

We present a novel algorithm for interface generation of software components. Given a component, our algorithm uses learning techniques to compute a permissive interface representing legal usage of the component. Unlike our previous work, this algorithm does not require knowledge about the component s environment. Furthermore, in contrast to other related approaches, our algorithm computes permissive interfaces even in the presence of non-determinism in the component. Our algorithm is implemented in the JavaPathfinder model checking framework for UML statechart components. We have also added support for automated assume-guarantee style compositional verification in JavaPathfinder, using component interfaces. We report on the application of the presented approach to the generation of interfaces for flight software components.

Giannakopoulou, Dimitra; Pasareanu, Corina

2009-01-01

244

Coral reefs on the edge? Carbon chemistry on inshore reefs of the great barrier reef.  

PubMed

While increasing atmospheric carbon dioxide (CO2) concentration alters global water chemistry (Ocean Acidification; OA), the degree of changes vary on local and regional spatial scales. Inshore fringing coral reefs of the Great Barrier Reef (GBR) are subjected to a variety of local pressures, and some sites may already be marginal habitats for corals. The spatial and temporal variation in directly measured parameters: Total Alkalinity (TA) and dissolved inorganic carbon (DIC) concentration, and derived parameters: partial pressure of CO2 (pCO2); pH and aragonite saturation state (?ar) were measured at 14 inshore reefs over a two year period in the GBR region. Total Alkalinity varied between 2069 and 2364 µmol kg-1 and DIC concentrations ranged from 1846 to 2099 µmol kg-1. This resulted in pCO2 concentrations from 340 to 554 µatm, with higher values during the wet seasons and pCO2 on inshore reefs distinctly above atmospheric values. However, due to temperature effects, ?ar was not further reduced in the wet season. Aragonite saturation on inshore reefs was consistently lower and pCO2 higher than on GBR reefs further offshore. Thermodynamic effects contribute to this, and anthropogenic runoff may also contribute by altering productivity (P), respiration (R) and P/R ratios. Compared to surveys 18 and 30 years ago, pCO2 on GBR mid- and outer-shelf reefs has risen at the same rate as atmospheric values (?1.7 µatm yr-1) over 30 years. By contrast, values on inshore reefs have increased at 2.5 to 3 times higher rates. Thus, pCO2 levels on inshore reefs have disproportionately increased compared to atmospheric levels. Our study suggests that inshore GBR reefs are more vulnerable to OA and have less buffering capacity compared to offshore reefs. This may be caused by anthropogenically induced trophic changes in the water column and benthos of inshore reefs subjected to land runoff. PMID:25295864

Uthicke, Sven; Furnas, Miles; Lønborg, Christian

2014-01-01

245

Coral Reefs on the Edge? Carbon Chemistry on Inshore Reefs of the Great Barrier Reef  

PubMed Central

While increasing atmospheric carbon dioxide (CO2) concentration alters global water chemistry (Ocean Acidification; OA), the degree of changes vary on local and regional spatial scales. Inshore fringing coral reefs of the Great Barrier Reef (GBR) are subjected to a variety of local pressures, and some sites may already be marginal habitats for corals. The spatial and temporal variation in directly measured parameters: Total Alkalinity (TA) and dissolved inorganic carbon (DIC) concentration, and derived parameters: partial pressure of CO2 (pCO2); pH and aragonite saturation state (?ar) were measured at 14 inshore reefs over a two year period in the GBR region. Total Alkalinity varied between 2069 and 2364 µmol kg?1 and DIC concentrations ranged from 1846 to 2099 µmol kg?1. This resulted in pCO2 concentrations from 340 to 554 µatm, with higher values during the wet seasons and pCO2 on inshore reefs distinctly above atmospheric values. However, due to temperature effects, ?ar was not further reduced in the wet season. Aragonite saturation on inshore reefs was consistently lower and pCO2 higher than on GBR reefs further offshore. Thermodynamic effects contribute to this, and anthropogenic runoff may also contribute by altering productivity (P), respiration (R) and P/R ratios. Compared to surveys 18 and 30 years ago, pCO2 on GBR mid- and outer-shelf reefs has risen at the same rate as atmospheric values (?1.7 µatm yr?1) over 30 years. By contrast, values on inshore reefs have increased at 2.5 to 3 times higher rates. Thus, pCO2 levels on inshore reefs have disproportionately increased compared to atmospheric levels. Our study suggests that inshore GBR reefs are more vulnerable to OA and have less buffering capacity compared to offshore reefs. This may be caused by anthropogenically induced trophic changes in the water column and benthos of inshore reefs subjected to land runoff. PMID:25295864

Uthicke, Sven; Furnas, Miles; Lønborg, Christian

2014-01-01

246

A design pathfinder with material correlation points for inflatable systems  

NASA Astrophysics Data System (ADS)

The incorporation of inflatable structures into aerospace systems can produce significant advantages in stowed volume to mechanical effectiveness and overall weight. Many applications of these ultra-lightweight systems are designed to precisely control internal or external surfaces, or both, to achieve desired performance. The modeling of these structures becomes complex due to the material nonlinearities inherent to the majority of construction materials used in inflatable structures. Furthermore, accurately modeling the response and behavior of the interfacing boundaries that are common to many inflatable systems will lead to better understanding of the entire class of structures. The research presented involved using nonlinear finite element simulations correlated with photogrammetry testing to develop a procedure for defining material properties for commercially available polyurethane-coated woven nylon fabric, which is representative of coated materials that have been proven materials for use in many inflatable systems. Further, the new material model was used to design and develop an inflatable pathfinder system which employs only internal pressure to control an assembly of internal membranes. This canonical inflatable system will be used for exploration and development of general understanding of efficient design methodology and analysis of future systems. Canonical structures are incorporated into the design of the phased pathfinder system to allow for more universal insight. Nonlinear finite element simulations were performed to evaluate the effect of various boundary conditions, loading configurations, and material orientations on the geometric precision of geometries representing typical internal/external surfaces commonly incorporated into inflatable pathfinder system. The response of the inflatable system to possible damage was also studied using nonlinear finite element simulations. Development of a correlated material model for analysis of the inflatable pathfinder system has improved the efficiency of design and analysis techniques of future inflatable structures. KEYWORDS: Nonlinear Finite Element, Inflatable Structures, Gossamer Space Systems, Photogrammetry Measurements, Coated Woven Fabric.

Fulcher, Jared Terrell

247

Characteristics of the TOVS Pathfinder Path A Dataset  

Microsoft Academic Search

The TIROS (Television Infrared Observation Satellite) Operational Vertical Sounder (TOVS) Pathfinder Path A dataset is currently a 9-yr dataset, 1985-93, of global fields of surface and atmospheric parameters derived from analysis of HIRS2 and MSU data on the NOAA-9, NOAA-10, NOAA-11, and NOAA-12 polar-orbiting operational meteorological satellites. The retrieved fields include land and ocean surface skin temperature, atmospheric temperature and

J. Susskind; P. Piraino; L. Rokke; L. Iredell; A. Mehta

1997-01-01

248

2005 PathfinderPlus Aero-Elastic Research Flight  

NASA Technical Reports Server (NTRS)

This viewgraph presentation describes the 2005 Pathfinder along with an investigation of its aeroelastic responses. The contents include: 1) HALE Class of Vehicles; 2) Aero-elastic Research Flights Overall Objective; 3) General Arrangement; 4) Sensor Locations; 5) NASA Ramp Operations; 6) Lakebed Operations; 7) 1st Flight Data Set; 8) Tool development / data usage; 9) HALE Tool Development & Validation; 10) Building a HALE Foundation; 11) Compelling Needs Drive HALE Efforts; and 12) Team Photo

Navarro, Robert

2005-01-01

249

Grid resolution and solution convergence for Mars Pathfinder forebody  

NASA Technical Reports Server (NTRS)

As part of the Discovery Program, NASA Plans to launch a series of probes to Mars. The Mars Pathfinder project is the first of this series with a scheduled Mars arrival in July 1997. The entry vehicle will perform a direct entry into the atmosphere and deliver a lander to the surface. Predicting the entry vehicle's flight performance and designing the forebody heatshield requires knowledge of the expected aerothermodynamic environment. Much of this knowledge can be obtained through computational fluid dynamic (CFD) analysis.

Nettelhorst, Heather L.; Mitcheltree, Robert A.

1994-01-01

250

JPL Experience with the Mars Pathfinder, Mission Simulation Battery  

NASA Technical Reports Server (NTRS)

A summary of the Mars Pathfinder Battery is given. The battery survived 47 days at 25 deg. C; it survived a 7 month stand at 10 to -5 deg. C; it met and exceeded 40 ampere-hour capacity for EDL; it met the 30 cycle minimum for Mars surface operation; and the project power profile for MArs surface operation does not yield energy balance.

Perrone, Dave; Ewell, Richard

1997-01-01

251

Chryse Planitia as a Mars Pathfinder landing site: The imperative of building on previous ground truth  

NASA Technical Reports Server (NTRS)

Based on consideration of the geological characteristics of Chryse Planitia, the requirements for Mars Pathfinder landing sites, the nature of the mission, the scale of the observations to be made, and the need to build outward from previous experience, a new mission to Chryse Planitia offers several advantages that are difficult to ignore as well as offering a low-gamble/high-return mission scenario. Considering the need to ensure a successful mission, and to ensure the continued health of planetary exploration, the reasons for a new mission to Chryse Planitia are compelling. Results of 1:500,000 mapping, operational benefits of Chryse Planitia, science benefits of Chryse Planitia, and conclusions and site recommendations are discussed.

Crumpler, Larry S.

1994-01-01

252

LISA and LISA Pathfinder: Gravitational Wave Observation in Space  

NASA Technical Reports Server (NTRS)

The Laser Interferometer Space Antenna (LISA) is a planned NASA-ESA gravitational wave observatory in the frequency range of 0.1 mHz--100 mHz. This observation band is inaccessible to ground-based detectors due to fluctuations in the Earth gravitational field. Gravitational wave sources for LISA include galactic binaries, mergers of supermassive black-hole binaries, extreme-mass-ratio inspirals, and cosmology backgrounds and bursts. LISA is a constellation of three spacecraft separated by 5 million km in an equilateral triangle, whose center follows the Earth in a heliocentric orbit with an orbital phase offset of 20 degrees. Challenging technology is required to ensure pure geodetic trajectories of the six onboard test masses, whose distance fluctuations will be measured by interspacecraft laser interferometers with picometer accuracy. LISA Pathfinder is an ESA-launched technology demonstration mission of key LISA subsystems such as spacecraft control with micronewton thrusters, test mass drag-free control, and precision laser interferometry between free-flying test masses. Ground testing of hardware of the Gravitational Reference Sensor and Optical Metrology subsystems of LISA Pathfinder is currently ongoing. A detailed description of the two missions and an overview of current investigations conducted by the community will be discussed. The current status in development and implementation of LISA Pathfinder pre-flight systems and latest results of the ongoing ground testing efforts will also be presented.

Guzman, Felipe

2010-01-01

253

76 FR 50181 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...  

Federal Register 2010, 2011, 2012, 2013, 2014

...red snapper and other reef fish to ensure public health and seafood quality are maintained. DATES: Comments must be received...and Federal waters off Louisiana to ensure public health and seafood quality are maintained. The EFP, if approved, would...

2011-08-12

254

Building coral reef resilience through assisted evolution  

PubMed Central

The genetic enhancement of wild animals and plants for characteristics that benefit human populations has been practiced for thousands of years, resulting in impressive improvements in commercially valuable species. Despite these benefits, genetic manipulations are rarely considered for noncommercial purposes, such as conservation and restoration initiatives. Over the last century, humans have driven global climate change through industrialization and the release of increasing amounts of CO2, resulting in shifts in ocean temperature, ocean chemistry, and sea level, as well as increasing frequency of storms, all of which can profoundly impact marine ecosystems. Coral reefs are highly diverse ecosystems that have suffered massive declines in health and abundance as a result of these and other direct anthropogenic disturbances. There is great concern that the high rates, magnitudes, and complexity of environmental change are overwhelming the intrinsic capacity of corals to adapt and survive. Although it is important to address the root causes of changing climate, it is also prudent to explore the potential to augment the capacity of reef organisms to tolerate stress and to facilitate recovery after disturbances. Here, we review the risks and benefits of the improvement of natural and commercial stocks in noncoral reef systems and advocate a series of experiments to determine the feasibility of developing coral stocks with enhanced stress tolerance through the acceleration of naturally occurring processes, an approach known as (human)-assisted evolution, while at the same time initiating a public dialogue on the risks and benefits of this approach. PMID:25646461

van Oppen, Madeleine J. H.; Oliver, James K.; Putnam, Hollie M.; Gates, Ruth D.

2015-01-01

255

Building coral reef resilience through assisted evolution.  

PubMed

The genetic enhancement of wild animals and plants for characteristics that benefit human populations has been practiced for thousands of years, resulting in impressive improvements in commercially valuable species. Despite these benefits, genetic manipulations are rarely considered for noncommercial purposes, such as conservation and restoration initiatives. Over the last century, humans have driven global climate change through industrialization and the release of increasing amounts of CO2, resulting in shifts in ocean temperature, ocean chemistry, and sea level, as well as increasing frequency of storms, all of which can profoundly impact marine ecosystems. Coral reefs are highly diverse ecosystems that have suffered massive declines in health and abundance as a result of these and other direct anthropogenic disturbances. There is great concern that the high rates, magnitudes, and complexity of environmental change are overwhelming the intrinsic capacity of corals to adapt and survive. Although it is important to address the root causes of changing climate, it is also prudent to explore the potential to augment the capacity of reef organisms to tolerate stress and to facilitate recovery after disturbances. Here, we review the risks and benefits of the improvement of natural and commercial stocks in noncoral reef systems and advocate a series of experiments to determine the feasibility of developing coral stocks with enhanced stress tolerance through the acceleration of naturally occurring processes, an approach known as (human)-assisted evolution, while at the same time initiating a public dialogue on the risks and benefits of this approach. PMID:25646461

van Oppen, Madeleine J H; Oliver, James K; Putnam, Hollie M; Gates, Ruth D

2015-02-24

256

Black reefs: iron-induced phase shifts on coral reefs  

PubMed Central

The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the shipwreck debris are characterized by high benthic cover of turf algae, macroalgae, cyanobacterial mats and corallimorphs, as well as particulate-laden, cloudy water. These sites also have very low coral and crustose coralline algal cover and are call black reefs because of the dark-colored benthic community and reduced clarity of the overlying water column. Here we use a combination of benthic surveys, chemistry, metagenomics and microcosms to investigate if and how shipwrecks initiate and maintain black reefs. Comparative surveys show that the live coral cover was reduced from 40 to 60% to <10% on black reefs on Millennium, Tabuaeran and Kingman. These three sites are relatively large (>0.75?km2). The phase shift occurs rapidly; the Kingman black reef formed within 3 years of the ship grounding. Iron concentrations in algae tissue from the Millennium black reef site were six times higher than in algae collected from reference sites. Metagenomic sequencing of the Millennium Atoll black reef-associated microbial community was enriched in iron-associated virulence genes and known pathogens. Microcosm experiments showed that corals were killed by black reef rubble through microbial activity. Together these results demonstrate that shipwrecks and their associated iron pose significant threats to coral reefs in iron-limited regions. PMID:21881615

Kelly, Linda Wegley; Barott, Katie L; Dinsdale, Elizabeth; Friedlander, Alan M; Nosrat, Bahador; Obura, David; Sala, Enric; Sandin, Stuart A; Smith, Jennifer E; Vermeij, Mark J A; Williams, Gareth J; Willner, Dana; Rohwer, Forest

2012-01-01

257

Black reefs: iron-induced phase shifts on coral reefs.  

PubMed

The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the shipwreck debris are characterized by high benthic cover of turf algae, macroalgae, cyanobacterial mats and corallimorphs, as well as particulate-laden, cloudy water. These sites also have very low coral and crustose coralline algal cover and are call black reefs because of the dark-colored benthic community and reduced clarity of the overlying water column. Here we use a combination of benthic surveys, chemistry, metagenomics and microcosms to investigate if and how shipwrecks initiate and maintain black reefs. Comparative surveys show that the live coral cover was reduced from 40 to 60% to <10% on black reefs on Millennium, Tabuaeran and Kingman. These three sites are relatively large (>0.75 km(2)). The phase shift occurs rapidly; the Kingman black reef formed within 3 years of the ship grounding. Iron concentrations in algae tissue from the Millennium black reef site were six times higher than in algae collected from reference sites. Metagenomic sequencing of the Millennium Atoll black reef-associated microbial community was enriched in iron-associated virulence genes and known pathogens. Microcosm experiments showed that corals were killed by black reef rubble through microbial activity. Together these results demonstrate that shipwrecks and their associated iron pose significant threats to coral reefs in iron-limited regions. PMID:21881615

Kelly, Linda Wegley; Barott, Katie L; Dinsdale, Elizabeth; Friedlander, Alan M; Nosrat, Bahador; Obura, David; Sala, Enric; Sandin, Stuart A; Smith, Jennifer E; Vermeij, Mark J A; Williams, Gareth J; Willner, Dana; Rohwer, Forest

2012-03-01

258

AAAS Feb `04 Frontiers in Coral Reef Research Climate Change and Coral Reefs  

E-print Network

AAAS Feb `04 Frontiers in Coral Reef Research Climate Change and Coral Reefs Joan A. Kleypas University of Kansas Lawrence, KS EARTH SeaWiFS image from: Orbimage #12;AAAS Feb `04 Frontiers in Coral Reef Feb `04 Frontiers in Coral Reef Research Effects of CO2 on Coral Reefs Reduced [CO3 2-] Increased

Kleypas, Joanie

259

Coral reef collapse spells danger for millions Island communities that depend on coral reef  

E-print Network

Coral reef collapse spells danger for millions Island communities that depend on coral reef (Canada), published in Current Biology. The report on island coral reef fisheries reveals that 55pc of coral reef would be needed ­ an area 3.7 times greater than Australia's Great Barrier Reef (pictured

Feigon, Brooke

260

Keeping Watch on Coral Reefs  

NSDL National Science Digital Library

This activity identifies and explains the benefits of and threats to coral reef systems. Students read tutorials, describe the role of satellites, analyze oceanographic data and identify actions that can be undertaken to reduce or eliminate threats to coral reefs. As a culminating activity, students prepare a public education program.

NOAA Ocean Service Education

261

Sandstone Cliffs in Capitol Reef  

USGS Multimedia Gallery

Sandstone cliffs in Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

262

Sandstone Cliff in Capitol Reef  

USGS Multimedia Gallery

A sandstone cliff in Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

263

Sandstone Monolith in Capitol Reef  

USGS Multimedia Gallery

A sandstone monolith in Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

264

Confronting the coral reef crisis  

Microsoft Academic Search

The worldwide decline of coral reefs calls for an urgent reassessment of current management practices. Confronting large-scale crises requires a major scaling-up of management efforts based on an improved understanding of the ecological processes that underlie reef resilience. Managing for improved resilience, incorporating the role of human activity in shaping ecosystems, provides a basis for coping with uncertainty, future changes

T. P. Hughes; C. Folke; M. Nyström; D. R. Bellwood

2004-01-01

265

MOC's Highest Resolution View of Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] (A) Mars Pathfinder site, left: April 1998; right: January 2000.

[figure removed for brevity, see original site] (B) top: April 1998; bottom: January 2000.

Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2 (September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder.

An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left.

As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles.

Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C, below.

[figure removed for brevity, see original site] (C) higher-resolution view; left: April 1998; right: January 2000.

[figure removed for brevity, see original site] D) Erroneous, preliminary identification of Mars Pathfinder location in January 2000 image. Subsequent analysis (Figures E & F, below) identified the correct spot.

The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) ca

2000-01-01

266

PBS Online NewsHour: Coral Reefs  

NSDL National Science Digital Library

In-depth coverage of the role of coral reefs in environment, medicinal properties, and conservation efforts, together with instructional materials. Includes lesson plan; interactive on coral-reef building blocks; extended interviews; and stories on reef threats, international treaties, Caribbean reefs, mangrove shields, and the Aquarius undersea lab. Main story is provided as text, streaming video, and RealAudio.

267

Possible refugia for reefs in times of environmental stress  

Microsoft Academic Search

This paper investigates the refuge potential of (1) upwelling areas, (2) coral areas at medium depth, and (3) offshore bank and island reefs in a scenario of increased global warming, and thus increased sea surface temperature (SST) and increased solar UV radiation. (1) Observations on coral health and water temperature in the subtropical Atlantic (Eleuthera and Cat Island, Bahamas) and

B. Riegl; W. E. Piller

2003-01-01

268

Capitol Reef National Park  

NSDL National Science Digital Library

This National Park Service (NPS) website provides an in-depth look at Capitol Reef National Park in Utah. Specifically, this covers the geology and natural resources of the park. There is a general overview of the geology of this area including the Waterpocket fold, Colorado Plateau, Cathedral Valley and erosion. There is a description of various rock colors and how they form, as well as a detailed stratigraphic column illustrating the names, thicknesses, and ancient environments of rocks and formations that exist in the park. The Natural Resources section discusses some of the history and archeology of the park, as well as birds, mammals, plants, reptiles and environmental problems.

269

The International Coral Reef Information Network  

NSDL National Science Digital Library

This extensive site was originally created to support coral reef conservation by the International Coral Reef Initiative (ICRI). The site serves to provide general coral reef information, tools and resources, and a central coral reef communications and network hub. The site also provides a library which houses descriptions of brochures, books, videos and other items suitable for coral reef awareness and education efforts. Some publications are available for download directly from this site, while others are available for purchase.

International Coral Reef Action Network (ICRAN)

270

Co-factors of LIM-HD transcription factors in neural development and axon pathfinding in zebrafish   

E-print Network

The zebrafish neuromuscular system is an elegant model to study neural development. To reveal a specific programme for zebrafish motor axon pathfinding I established a method to selectively block motor axon pathfinding ...

Zhong, Zhen

2012-06-22

271

Predicting the impact of present and future human land-use on the Great Barrier Reef  

NASA Astrophysics Data System (ADS)

An ecohydrologic model, verified against field data, suggests that land-use has contributed to degradation of the health of the Great Barrier Reef and to an increased frequency and intensity of crown-of-thorns starfish infestations. The model also predicts that the health of the Great Barrier Reef will significantly worsen by the year 2050 as a result of global warming. However, the model also suggests that much-improved land-use practices will enable some regions of the Great Barrier Reef to recover, even with global warming. Finally, the model suggests that, if global warming proceeds unchecked, biological adaptation is necessary to avoid a collapse of the Great Barrier Reef health by the year 2100.

Wolanski, Eric; De'ath, Glenn

2005-08-01

272

Coral reef aorta, emergency surgical: case report and literature review.  

PubMed

Coral reef aorta is described as an uncommon entity characterized by the presence of coarse calcifications, which are developed in the visceral aorta. These calcifications grow toward the lumen of the artery and can result in significant stenosis, so that causing malperfusion of the lower limbs, visceral ischemia or hypertension secondary to renal involvement. We report here a case of a 54-year-old patient with coral reef aorta and symptomatic. The clinical presentation of the patient required the surgical approach. A review of literature in major databases was conducted to compare health-related aspects of the disease presentation and management. Coral reef aorta should be considered as the diagnosis for patients with visceral and limbs ischemia. The approach in our case was consistent with other studies previously published in the literature. PMID:25003933

Belczak, Sergio Quilici; Sincos, Igor Rafael; Aun, Ricardo; Costa, Kaline Viana; Araujo, Etianne Andrade

2014-04-01

273

Measuring coral reef community metabolism using new benthic chamber technology  

USGS Publications Warehouse

Accurate measurement of coral reef community metabolism is a necessity for process monitoring and in situ experimentation on coral reef health. Traditional methodologies used for these measurements are effective but limited by location and scale constraints. We present field trial results for a new benthic chamber system called the Submersible Habitat for Analyzing Reef Quality (SHARQ). This large, portable incubation system enables in situ measurement and experimentation on community- scale metabolism. Rates of photosynthesis, respiration, and calcification were measured using the SHARQ for a variety of coral reef substrate types on the reef flat of South Molokai, Hawaii, and in Biscayne National Park, Florida. Values for daily gross production, 24-h respiration, and net calcification ranged from 0.26 to 6.45 g O2 m-2 day-1, 1.96 to 8.10 g O2 m-2 24 h-1, and 0.02 to 2.0 g CaCO3 m -2 day-1, respectively, for all substrate types. Field trials indicate that the SHARQ incubation chamber is an effective tool for in situ isolation of a water mass over a variety of benthic substrate types for process monitoring, experimentation, and other applications.

Yates, K.K.; Halley, R.B.

2003-01-01

274

Miocene reef corals: A review  

SciTech Connect

Tectonic blockage in the Middle East of westward-flowing Tethys surface circulation during the latest Oligocene led to creation in the earliest Miocene of endemic Mediterranean, Western Atlantic-Caribbean, and Indo-Pacific realms. A great reduction in reef coral diversity from 60-80 Oligocene species to 25-35 early Miocene species occurred in the Western Atlantic-Caribbean and Mediterranean areas accompanied by a decrease in reef growth. A slower and less drastic change apparently occurred in the Indo-Pacific area. Early Miocene reef corals of the Western Atlantic-Caribbean comprise a transition between the cosmopolitan Oligocene fauna and its endemic mid-Miocene to modern counterpart. Although early Miocene reefs were dominated by a Porites-Montastrea assemblage, eastward flow of Pacific circulation brought with it ''exotic'' corals such as Coscinaraea and Pseudocolumnastrea. Also, many cosmopolitan genera persisted from the Oligocene. During the middle to late Miocene, most of the species still living on Holocene reefs evolved. As the Mediterranean basin became more restricted, there was a slow decline in reef corals from 20 - 25 species in the Aquitainian to less than five species in the Messinian. Eustatic lowstand led to the extinction of reef-building corals in the late Messinian. In the Indo-Pacific, Neogene evolution of reef corals was conservative. Excluding the Acroporidae and Seriatoporidae, most Holocene framework species had evolved by the middle Miocene. Interplay between regional tectonics and eustatic sea level changes led to extensive development of middle to late Miocene pinnacle reefs over the southwestern Pacific.

Frost, S.H.

1988-01-01

275

Widespread Reduction in Coral Growth Rates on the Mesoamerican Reef Following the 1998 El Nino and Hurricane Mitch  

Microsoft Academic Search

Corals on the Mesoamerican Reef have been declining in health over the past few decades, and it is important to determine the cause, if conservation measures are to be effective. Cores from large Montastrea spp., Diploria strigosa, and Siderastrea siderea corals were collected in two locations on the Belizean barrier reef: 34 from Frank's Caye, Sapodilla Cayes, in the southern

J. E. Carilli; R. D. Norris; K. A. Hughen

2006-01-01

276

Reduction and Analysis of Meteorology Data from the Mars Pathfinder Lander  

NASA Technical Reports Server (NTRS)

Dr. James Murphy is a member of the Mars Pathfinder Atmospheric Structure Investigation Meteorology (ASI/MET) Science Team. The activities of Dr. Murphy, and his collaborators are summarized in this report, which reviews the activities in support of the analysis of the meteorology data from the Mars Pathfinder Lander.

Murphy, James R.; Bridger, Alison F. C.; Haberle, Robert M.

1998-01-01

277

PathFinder: a negotiation-based performance-driven router for FPGAs  

Microsoft Academic Search

Routing FPGAs is a challenging problem because of the relative scarcity of routing resources, both wires and connection points. This can lead either to slow implementations caused by long wiring paths that avoid congestion or a failure to route all signals. This paper presents PathFinder, a router that balances the goals of performance and routability. PathFinder uses an iterative algorithm

Larry McMurchie; Carl Ebeling

1995-01-01

278

NASA Ocean Altimeter Pathfinder Project. Report 1; Data Processing Handbook  

NASA Technical Reports Server (NTRS)

The NOAA/NASA Pathfinder program was created by the Earth Observing System (EOS) Program Office to determine how satellite-based data sets can be processed and used to study global change. The data sets are designed to be long time-sedes data processed with stable calibration and community consensus algorithms to better assist the research community. The Ocean Altimeter Pathfinder Project involves the reprocessing of all altimeter observations with a consistent set of improved algorithms, based on the results from TOPEX/POSEIDON (T/P), into easy-to-use data sets for the oceanographic community for climate research. This report describes the processing schemes used to produce a consistent data set and two of the products derived f rom these data. Other reports have been produced that: a) describe the validation of these data sets against tide gauge measurements and b) evaluate the statistical properties of the data that are relevant to climate change. The use of satellite altimetry for earth observations was proposed in the early 1960s. The first successful space based radar altimeter experiment was flown on SkyLab in 1974. The first successful satellite radar altimeter was flown aboard the Geos-3 spacecraft between 1975 and 1978. While a useful data set was collected from this mission for geophysical studies, the noise in the radar measured and incomplete global coverage precluded ft from inclusion in the Ocean Altimeter Pathfinder program. This program initiated its analysis with the Seasat mission, which was the first satellite radar altimeter flown for oceanography.

Koblinsky, C. J.; Beckley, Brian D.; Ray, Richard D.; Wang, Yan-Ming; Tsaoussi, Lucia; Brenner, Anita; Williamson, Ron

1998-01-01

279

Laser Interferometry for Gravitational Wave Observation: LISA and LISA Pathfinder  

NASA Technical Reports Server (NTRS)

The Laser Interferometer Space Antenna (LISA) is a planned NASA-ESA gravitational wave observatory in the frequency range of 0.1mHz-100mHz. This observation band is inaccessible to ground-based detectors due to the large ground motions of the Earth. Gravitational wave sources for LISA include galactic binaries, mergers of supermasive black-hole binaries, extreme-mass-ratio inspirals, and possibly from as yet unimagined sources. LISA is a constellation of three spacecraft separated by 5 million km in an equilateral triangle, whose center follows the Earth in a heliocentric orbit with an orbital phase offset oF 20 degrees. Challenging technology is required to ensure pure geodetic trajectories of the six onboard test masses, whose distance fluctuations will be measured by interspacecraft laser interferometers with picometer accuracy. LISA Pathfinder is an ESA-launched technology demonstration mission of key LISA subsystems such us spacecraft control with micro-newton thrusters, test mass drag-free control, and precision laser interferometry between free-flying test masses. Ground testing of flight hardware of the Gravitational Reference Sensor and Optical Metrology subsystems of LISA Pathfinder is currently ongoing. An introduction to laser interferometric gravitational wave detection, ground-based observatories, and a detailed description of the two missions together with an overview of current investigations conducted by the community will bc discussed. The current status in development and implementation of LISA Pathfinder pre-flight systems and latest results of the ongoing ground testing efforts will also be presented

Guzman, Felipe

2010-01-01

280

The Data Processor of the JEM-EUSO pathfinders  

NASA Astrophysics Data System (ADS)

JEM-EUSO is a wide-angle refractive UV telescope being proposed for attachment to the Japanese Experiment Module on ISS. The main goal of the mission is to study Extreme Energy Cosmic Rays. Two pathfinder mission are now in progress: EUSO-TA and EUSO-Balloon. The EUSO-TA project foresees the installation of a telescope prototype in the Telescope Array site. The aim of this project is to calibrate the telescope with the TA fluorescence detector. An initial run of one year starting from 2013 is foreseen. EUSO-Balloon is a pathfinder mission in which a prototype telescope will be mounted on a stratospheric balloon. The main aim of this mission is to perform a end-to-end test of all the key technologies and instrumentation of JEM-EUSO detectors and to prove the global detection chain. EUSO-Balloon will measure the UV background fundamental for the development of the simulations. EUSO-Balloon has the potential to detect Extensive Air Showers from above, paving the way for any future space-based EECR observatory. We will present the Data Processor of the pathfinders. The DP is the component of the Electronics System which performs data management and instrument control. The DP controls front-end electronics, performs 2nd level trigger filtering, tags events with arrival time and payload position through a GPS system, manages mass memory for data storage, measures live and dead time of the telescope, provides signals for time synchronization of the event, performs housekeeping monitor and handles interface to the telemetry system. We will describe the main components of the DP, the state-of-the-art and the results of the tests carried out.

Scotti, V.; Osteria, G.

2014-06-01

281

Age of tilted reefs, Hawaii.  

USGS Publications Warehouse

Submerged carbonate reefs are preserved as a series of submarine terraces between Molokai and Hawaii along a 200-km span of the SE Hawaiian Ridge. Limestones from 2 of the terraces have been dated at 13 and 120 ka. Recognition that the terraces are tilted permits assignment of about a dozen terraces from 150 to 1300 m depth to 8 general reef platforms. These reefs were drowned by the combined effects of island subsidence and sea level rise at the end of successive glacial stages from 13 to 647 ka. The platforms are tilted 5 m/km SE toward the locus of volcanic centered on the island of Hawaii.-from Authors

Moore, J.G.; Campbell, J.F.

1987-01-01

282

Expeditions in Conservation: Mesoamerican Reef  

NSDL National Science Digital Library

The World Wildlife Fund (WWF) recently completed this expedition of the largest coral reef system in the Atlantic Ocean and has provided an opportunity for Web users to share some of what they experienced. Visitors can view spectacular photos and videos to learn about the reef and the creatures that reside there, as well as read the daily reports of the expedition. The site offers much more in terms of learning about coral reefs, the people who study them, and the threats that face these unique ecosystems.

1969-12-31

283

[Ciguatoxin and edible reef fishes].  

PubMed

Referring to the various human and animal clinical response to consumption of reef fish, the authors precise the importance of ingested dose and the role of cumulative effects. They point out the arbitrary character of distinguishing poisonous and edible fish of the same species. At the light of these data they find ciguatoxin in edible fish from known latent ciguateric potential species in atoxic areas. Therefore ciguatoxin does appear as a natural biotoxin permanently produced in most of the polynesian coral reefs ecosystems. The occurence of clinical disorders by men and animals results from a sudden increase of its production following biological transitory modification of some coral reef biota. PMID:1243745

Bagnis, R; Vernoux, J P

1975-01-01

284

Missile tracking and range safety: Tracking Interferometer Pathfinder System (TIPS)  

NASA Astrophysics Data System (ADS)

The tracking of missiles at close range proximity has been an ongoing challenge for many launch environments. The ability to provide accurate missile trajectory information is imperative for range safety and early termination of flight. In an effort to provide a potential solution to tracking issues that have plagued many traditional techniques, the Tracking Interferometer Pathfinder System (TIPS) was developed at the Naval Research Laboratory, Washington, D.C. The paper herein describes the design, field test, and results of an interferometer deployed for missile tracking.

Dowgiallo, David J.; Rauen, Stephen; Peters, Wendy M.; Polisensky, Emil J.

2013-05-01

285

Closed Loop Simulations of the Thermal Experiments in LISA Pathfinder  

NASA Astrophysics Data System (ADS)

The thermal experiments to be carried out onboard LISA Pathfinder (LPF) will provide essential information of the dependences of the instrument with respect to temperature variations. These thermal experiments must be modelled and simulated both to be validated for mission operations purposes and also to develop a data analysis tool able to characterise the temperature noise contribution to the instrument performance. Here we will present the models developed and the simulated signals for some of the experiments together with the corresponding interferometer readouts, the latter being computed by combining the thermal models with the global LTP (LISA Technology Package) simulator of the LTP Data Analysis team.

Gibert, F.; Nofrarias, M.; Karnesis, N.; Díaz-Aguiló, M.; Mateos, I.; Lobo, A.; Gesa, L.; Martín, V.; Lloro, I.

2013-01-01

286

The LISA PathFinder DMU Software, a Global Overview  

NASA Astrophysics Data System (ADS)

During the last 6 years, the IEEC software team has developed the Data Management Unit (DMU) software. It is a critical piece of engineering in the Lisa Pathfinder mission, in charge of the primary processing of data generated by the Phasemeter, acting also as an interface between the whole LISA Technology Package (LTP) and the On-Board Computer (OBC). It also manages and controls the diagnostics systems (Heaters, coils, magnetometers, radiation monitor, thermometers). This article briefly summarizes all the work performed, describing the complex environment built around the application generation.

Gesa, L.; Martin, V.; Conchillo, A.; Lobo, A.; Lloro, I.

2013-01-01

287

Symbolic PathFinder: Symbolic Execution of Java Bytecode  

NASA Technical Reports Server (NTRS)

Symbolic Pathfinder (SPF) combines symbolic execution with model checking and constraint solving for automated test case generation and error detection in Java programs with unspecified inputs. In this tool, programs are executed on symbolic inputs representing multiple concrete inputs. Values of variables are represented as constraints generated from the analysis of Java bytecode. The constraints are solved using off-the shelf solvers to generate test inputs guaranteed to achieve complex coverage criteria. SPF has been used successfully at NASA, in academia, and in industry.

Pasareanu, Corina S.; Rungta, Neha

2010-01-01

288

ER-20037 LLNL eternal pathfinder wing spar design study report  

SciTech Connect

This document outlines the results of a design study performed by EDO-FSD on the LLNL Eternal Pathfinder Wing Spar/Fuel Tank. The main focus of the design study was the weight minimization of the composite wall of the mid span spar section of the aircraft. The torque, shear, moment and pressure loading requirements, as well as LLNL`s preliminary drawings, were used to develop a reduced weight mid-span spar design. The design study also encompassed details such as the pressure bulkheads, wing rod connectors, and attachment flanges.

Not Available

1994-03-01

289

Rock and Soil Types at Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

Type areas of rocks and soils. (A) Dark rock type and bright soil type: Shown is the dark rock Barnacle Bill. Reflectance spectra typical of fresh basalt and APXS spectra indicating more silica-rich basaltic andesite compositions characterize this type. These rocks are typically the small boulders and intermediate-sized cobbles at the Pathfinder site. The bright soil type is very common and in this case comprises Barnacle Bill's wind tail and much of the surround soil area. This soil has a high reflectance and a strongly reddened spectrum indicative of oxidized ferric minerals. (B) Bright rock type: Shown is the bright rock Wedge. Reflectance spectra typical of weathered basalt and APXS spectra indicating basaltic compositions characterize this type. These rocks are typically larger than 1 meter in diameter and many display morphologies indicating flood deposition. (C) Pink rock type: Shown is the pink rock Scooby Doo. APXS and reflectance spectra indicate a composition and optical characteristics similar to the drift soil. However, the morphology of the pink rock type indicates a cemented or rocklike structure. This material may be a chemically cemented hardpan that underlies much of the Pathfinder site. (D) Dark soil type: The dark soil type is typically found on the windward sides of rocks or in rock-free areas like Photometry Flats (shown here) where the bright soil has been striped away by aeolian action or in open areas. Other locations include the Mermaid Dune. (E) Disturbed soil type: The darkening of disturbed soil relative to its parent material, bright soil, as a result of changes in soil texture and compaction caused by movement of the rover and retraction of the lander airbag. (F) Lamb-like soil type: This soil type shows reflectance and spectral characteristics intermediate between the bright and dark soils. Its distinguishing feature is a weak spectral absorption near 900 nanometers not seen in either the bright or dark soils.

NOTE: original caption as published in Science Magazine

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

290

Effectiveness of benthic foraminiferal and coral assemblages as water quality indicators on inshore reefs of the Great Barrier Reef, Australia  

NASA Astrophysics Data System (ADS)

Although the debate about coral reef decline focuses on global disturbances (e.g., increasing temperatures and acidification), local stressors (nutrient runoff and overfishing) continue to affect reef health and resilience. The effectiveness of foraminiferal and hard-coral assemblages as indicators of changes in water quality was assessed on 27 inshore reefs along the Great Barrier Reef. Environmental variables (i.e., several water quality and sediment parameters) and the composition of both benthic foraminiferal and hard-coral assemblages differed significantly between four regions (Whitsunday, Burdekin, Fitzroy, and the Wet Tropics). Grain size and organic carbon and nitrogen content of sediments, and a composite water column parameter (based on turbidity and concentrations of particulate matter) explained a significant amount of variation in the data (tested by redundancy analyses) in both assemblages. Heterotrophic species of foraminifera were dominant in sediments with high organic content and in localities with low light availability, whereas symbiont-bearing mixotrophic species were dominant elsewhere. A similar suite of parameters explained 89% of the variation in the FORAM index (a Caribbean coral reef health indicator) and 61% in foraminiferal species richness. Coral richness was not related to environmental setting. Coral assemblages varied in response to environmental variables, but were strongly shaped by acute disturbances (e.g., cyclones, Acanthaster planci outbreaks, and bleaching), thus different coral assemblages may be found at sites with the same environmental conditions. Disturbances also affect foraminiferal assemblages, but they appeared to recover more rapidly than corals. Foraminiferal assemblages are effective bioindicators of turbidity/light regimes and organic enrichment of sediments on coral reefs.

Uthicke, S.; Thompson, A.; Schaffelke, B.

2010-03-01

291

Home Reef, South Pacific  

NASA Technical Reports Server (NTRS)

In the South Pacific, south of Late Island along the Tofua volcanic arc in Tonga, a new volcanic island Home Reef is being re-born. The island is thought to have emerged after a volcanic eruption in mid-August that has also spewed large amounts of floating pumice into Tongan waters and sweeping across to Fiji about 350 km (220 miles) to the west of where the new island has formed. In 2004 a similar eruption created an ephemeral island about 0.5 by 1.5 km (0.3 by 0.9 miles) in size; it was no longer visible in an ASTER image acquired November 2005. This simulated natural color image shows the vegetation-covered stratovolcanic island of Late in the upper right. Home Reef is found in the lower left. The two bluish plumes are hot seawater that is laden with volcanic ash and chemicals; the larger one can be traced for more than 14 km (8.4 miles) to the east. The image was acquired October 10, 2006 and covers an area of 24.3 by 30.2 km. It is located at 18.9 degrees South latitude, 174.7 degrees west longitude.

With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Size: 24.3 by 30.2 kilometers (15 by 18.6 miles) Location: 18.9 degrees South latitude, 174.7 degrees West longitude Orientation: North at top Image Data: ASTER bands 3, 2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: October 4, 2006

2006-01-01

292

Commencement on a Coral Reef  

ERIC Educational Resources Information Center

Describes an environmental program in which sixteen students and three biology teachers from Northfield Mount Hermon School in Massachusetts spent two weeks examining the ecology of a Caribbean reef.. (JR)

Webster, Steven K.

1973-01-01

293

Sandstone Formations in Capitol Reef  

USGS Multimedia Gallery

Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

294

Artificial Reefs and Ocean Dumping.  

ERIC Educational Resources Information Center

Activities and instructional strategies for two multigrade lessons are provided. Activity objectives include describing an artificial reef (such as a sunken ocean liner) as an ecosystem, knowing animal types in the ecosystem, and describing a food web. (JN)

Glueck, Richard D.

1983-01-01

295

Fish Assemblages on Estuarine Artificial Reefs: Natural Rocky-Reef Mimics or Discrete Assemblages?  

PubMed Central

If the primary goal of artificial reef construction is the creation of additional reef habitat that is comparable to adjacent natural rocky-reef, then performance should be evaluated using simultaneous comparisons with adjacent natural habitats. Using baited remote underwater video (BRUV) fish assemblages on purpose-built estuarine artificial reefs and adjacent natural rocky-reef and sand-flat were assessed 18 months post-deployment in three south-east Australian estuaries. Fish abundance, species richness and diversity were found to be greater on the artificial reefs than on either naturally occurring reef or sand-flat in all estuaries. Comparisons within each estuary identified significant differences in the species composition between the artificial and natural rocky-reefs. The artificial reef assemblage was dominated by sparid species including Acanthopagrus australis and Rhabdosargus sarba. The preference for a range of habitats by theses sparid species is evident by their detection on sand-flat, natural rocky reef and artificial reef habitats. The fish assemblage identified on the artificial reefs remained distinct from the adjacent rocky-reef, comprising a range of species drawn from naturally occurring rocky-reef and sand-flat. In addition, some mid-water schooling species including Trachurus novaezelandiae and Pseudocaranx georgianus were only identified on the artificial reef community; presumably as result of the reef's isolated location in open-water. We concluded that estuarine artificial reef assemblages are likely to differ significantly from adjacent rocky-reef, potentially as a result of physical factors such as reef isolation, coupled with species specific behavioural traits such as the ability of some species to traverse large sand flats in order to locate reef structure, and feeding preferences. Artificial reefs should not be viewed as direct surrogates for natural reef. The assemblages are likely to remain distinct from naturally occurring habitat comprised of species that reside on a range of adjacent natural habitats. PMID:23755106

Folpp, Heath; Lowry, Michael; Gregson, Marcus; Suthers, Iain M.

2013-01-01

296

Reef Bioerosion: Agents and Processes  

Microsoft Academic Search

\\u000a Coral reef maintenance depends on the balance between constructive and destructive forces. Constructive forces are mainly\\u000a calcification and growth of corals and encrusting coralline algae. Destructive forces comprise physical, chemical, and biological\\u000a erosion. Bioerosion is considered as the main force of reef degradation because physical erosion (storms) is temporary and\\u000a localized, and chemical erosion is considered as negligible due to

Aline Tribollet; Stjepko Golubic

297

Private development of artificial reefs  

E-print Network

PRIVATE DEVFLOPMENT OF ARTIFICIAL REEFS A Thesis ARTHUR ALLEN BURNS, JR. Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject...: Management PRIVATE DEVELOPMENT OF ARTIFICIAL REEFS A Thesis by ARTHUR ALLEN BURNS, JR. Approved as to style and content by: irman o t e Committee { ead o the Depa tment ~Member Memb e- December 1978 12409Ei'7 ABSTRACT Private Development...

Burns, Arthur Allen

1978-01-01

298

Florida Keys NMS: Coral Reefs  

NSDL National Science Digital Library

Florida Keys National Marine Sanctuary's page with information on coral reefs and links to information on research, restoration and monitoring. Wealth of information on the protection of Florida's coral reefs and the Florida Keys as a whole. Includes an in-class activity for grades K-5, as well as information on a Keys field experience and teacher workshops. Information on safe diving and snorkeling. Education materials available for purchase, including the Seagrass Toolbox.

299

Lab 3: Building a Reef  

NSDL National Science Digital Library

During this lab, students learn about the life cycle of corals, including how they grow and reproduce. Students consider the chemistry of seawater and the importance of the symbiotic relationship between corals and zooxanthellae in the formation of coral reefs. They blow CO2 through calcium hydroxide (limewater) to model how respiration assists coral in precipitating calcium carbonate. Students also build on the coral polyp models they made in Lab 2 to demonstrate coral growth, reproduction, and reef formation.

300

Ecology of the south Florida coral reefs: a community profile  

SciTech Connect

An overview of coral reef research in southern Florida is provided as a prelude to a genuine description of the coral reef ecosystem in the Florida Keys and surrounding environments. Coral reef community types, reef benthos, plankton and reef fish are given specific treatment. Coral reef ecology and management are described. 27 figs., 31 tabs.

Jaap, W.C.

1984-08-01

301

Sedimentary Geochemistry of Martian Samples from the Pathfinder Mission  

NASA Technical Reports Server (NTRS)

The purpose of this research project was to evaluate the APXS data collected on soils and rocks at the Pathfinder site in terms of sedimentary geochemistry. Below are described the major findings of this research: (1) An influential model to explain the chemical variation among Pathfinder soils and rocks is a two component mixing model where rocks of fairly uniform composition mix with soil of uniform composition; (2) The very strong positive correlation between MgO and SO, points to a control by a MgSO4 mineral however, spectroscopic data continue to suggest that Fe-sulfates, notably schwertmannite and jarosite, may be important components; (3) In an attempt to better understand the causes of complexities in mixing relationships, the possible influence of sedimentary transport has been evaluated; (4) Another aspect of this research has been to examine the possibility of sedimentary silica being a significant phase on Mars; and (5) On Earth, the geochemistry of sedimentary rocks has been used to constrain the chemical composition of the continental crust and an important part of this research was to evaluate this approach for Mars.

McLennan, Scott M.

2001-01-01

302

Mars Pathfinder and Mars Global Surveyor Outreach Compilation  

NASA Astrophysics Data System (ADS)

This videotape is a compilation of the best NASA JPL (Jet Propulsion Laboratory) videos of the Mars Pathfinder and Mars Global Surveyor missions. The mission is described using animation and narration as well as some actual footage of the entire sequence of mission events. Included within these animations are the spacecraft orbit insertion; descent to the Mars surface; deployment of the airbags and instruments; and exploration by Sojourner, the Mars rover. JPL activities at spacecraft control during significant mission events are also included at the end. The spacecraft cameras pan the surrounding Mars terrain and film Sojourner traversing the surface and inspecting rocks. A single, brief, processed image of the Cydonia region (Mars face) at an oblique angle from the Mars Global Surveyor is presented. A description of the Mars Pathfinder mission, instruments, landing and deployment process, Mars approach, spacecraft orbit insertion, rover operation are all described using computer animation. Actual color footage of Sojourner as well as a 360 deg pan of the Mars terrain surrounding the spacecraft is provided. Lower quality black and white photography depicting Sojourner traversing the Mars surface and inspecting Martian rocks also is included.

1999-09-01

303

Mars Pathfinder and Mars Global Surveyor Outreach Compilation  

NASA Technical Reports Server (NTRS)

This videotape is a compilation of the best NASA JPL (Jet Propulsion Laboratory) videos of the Mars Pathfinder and Mars Global Surveyor missions. The mission is described using animation and narration as well as some actual footage of the entire sequence of mission events. Included within these animations are the spacecraft orbit insertion; descent to the Mars surface; deployment of the airbags and instruments; and exploration by Sojourner, the Mars rover. JPL activities at spacecraft control during significant mission events are also included at the end. The spacecraft cameras pan the surrounding Mars terrain and film Sojourner traversing the surface and inspecting rocks. A single, brief, processed image of the Cydonia region (Mars face) at an oblique angle from the Mars Global Surveyor is presented. A description of the Mars Pathfinder mission, instruments, landing and deployment process, Mars approach, spacecraft orbit insertion, rover operation are all described using computer animation. Actual color footage of Sojourner as well as a 360 deg pan of the Mars terrain surrounding the spacecraft is provided. Lower quality black and white photography depicting Sojourner traversing the Mars surface and inspecting Martian rocks also is included.

1999-01-01

304

Case for testing modified Newtonian dynamics using LISA pathfinder  

NASA Astrophysics Data System (ADS)

We quantify the potential for testing modified Newtonian dynamics (MOND) with Laser Interferometer Space Antenna pathfinder, should a saddle point fly-by be incorporated into the mission. We forecast the expected signal-to-noise ratio for a variety of instrument noise models and trajectories past the saddle. For standard theoretical parameters, the signal-to-noise ratio reaches middle to high double figures even with modest assumptions about instrument performance and saddle approach. Obvious concerns, like systematics arising from Laser Interferometer Space Antenna pathfinder self-gravity, or the Newtonian background, are examined and shown not to be a problem. We also investigate the impact of a negative observational result upon the free function determining the theory. We demonstrate that, if Newton’s gravitational constant is constrained to not be renormalized by more than a few percent, only contrived MONDian free functions would survive a negative result. There are exceptions, e.g. free functions not asymptoting to 1 in the Newtonian limit, but rather diverging or asymptoting to zero (depending on their mother relativistic MONDian theory). Finally, we scan the structure of all proposed relativistic MONDian theories, and classify them with regards to their nonrelativistic limit, finding three broad cases (with a few subcases depending on the form of the free function). It is appears that only the Einstein-Aether formulation, and the subcases where the free function does not asymptote to 1 in other theories, would survive a negative result without resorting to “designer” free functions.

Magueijo, João; Mozaffari, Ali

2012-02-01

305

Design of the magnetic diagnostics unit onboard LISA Pathfinder  

E-print Network

LISA (Laser Interferometer Space Antenna) is a joint mission of ESA and NASA which aims to be the first space-borne gravita- tional wave observatory. Due to the high complexity and technological challenges that LISA will face, ESA decided to launch a technological demonstrator, LISA Pathfinder. The payload of LISA Pathfinder is the so-called LISA Technology Package, and will be the highest sensitivity geodesic explorer flown to date. The LISA Technology Package is designed to measure relative accelerations between two test masses in nominal free fall (geodesic motion). The magnetic, thermal and radiation disturbances affecting the payload are monitored and dealt by the diagnostics subsystem. The diagnostics subsystem consists of several modules, and one of these is the magnetic diagnostics unit. Its main function is the assessment of differential acceleration noise between test masses due to the magnetic effects. To do so, it has to determine the magnetic characteristics of the test masses, namely their magnetic remanences and susceptibilities. In this paper we show how this can be achieved to the desired accuracy.

Marc Diaz-Aguiló; Ignacio Mateos; Juan Ramos-Castro; Alberto Lobo; Enrique García-Berro

2012-02-13

306

Revised electrostatic model of the LISA Pathfinder inertial sensor  

NASA Astrophysics Data System (ADS)

A comprehensive electrostatic finite-element (FE) analysis of the LISA Pathfinder Inertial Sensor (IS) has been carried out at Astrium GmbH. Starting with a detailed geometrical model of the IS housing and test mass (TM) flight units, FE results were derived from multiple analyses runs applying the Maxwell 3D field simulation software. The electrostatic forces and torques on the TM in 6DoF, as well as all non-negligible capacitances between the TM, the 18 electrodes, and the housing, have been extracted for different TM translations and rotations. The results of the FE analyses were expected to confirm the existing IS electrostatic model predictions used for performance analysis, simulations, and on-board algorithms. Major discrepancies were found, however, between the results and the model used so far. In general, FE results give considerably larger capacitance values than the equivalent infinite non-parallel plate estimates. In contrast, the FE derived forces and torques are in general significantly lower compared to the analytic IS electrostatic model predictions. In this paper, these results are discussed in detail and the reasons for the deviations are elaborated. Based on these results, an adapted analytic IS electrostatic model is proposed that reflects the electrostatic forces, torques, and stiffness values in the LISA Pathfinder IS significantly more accurate.

Brandt, Nico; Fichter, Walter

2009-03-01

307

LISA Pathfinder: hardware tests and their input to the mission  

NASA Astrophysics Data System (ADS)

The Laser Interferometer Space Antenna (LISA) is a joint ESA-NASA mission for the first space-borne gravitational wave detector. LISA aims to detect sources in the 0.1mHz to 1Hz range, which include supermassive black holes and galactic binary stars. Core technologies required for the LISA mission, including drag-free test mass control, picometre interferometry and micro-Newton thrusters, cannot be tested on-ground. Therefore, a precursor satellite, LISA Pathfinder, has been developed as a technology demonstration mission. The preparations for the LISA Pathfinder mission have reached an exciting stage. Tests of the engineering model of the optical metrology system have recently been completed at the Albert Einstein Institute, Hannover, and flight model tests are now underway. Significantly, they represent the first complete integration and testing of the space-qualified hardware and are the first tests on system level. The results and test procedures of these campaigns will be utilised directly in the ground-based flight hardware tests, and subsequently within in-flight operations. In addition, they allow valuable testing of the data analysis methods using the MatLab based LTP data analysis toolbox. This contribution presents an overview of the test campaigns calibration, control and perfor-mance results, focusing on the implications for the Experimental Master Plan which provides the basis for the in-flight operations and procedures.

Audley, Heather

308

Microbiota of the major South Atlantic reef building coral Mussismilia.  

PubMed

The Brazilian endemic scleractinian corals, genus Mussismilia, are among the main reef builders of the South Atlantic and are threatened by accelerating rates of disease. To better understand how holobiont microbial populations interact with corals during health and disease and to evaluate whether selective pressures in the holobiont or neutral assembly shape microbial composition, we have examined the microbiota structure of Mussismilia corals according to coral lineage, environment, and disease/health status. Microbiota of three Mussismilia species (Mussismilia harttii, Mussismilia hispida, and Mussismilia braziliensis) was compared using 16S rRNA pyrosequencing and clone library analysis of coral fragments. Analysis of biological triplicates per Mussismilia species and reef site allowed assessment of variability among Mussismilia species and between sites for M. braziliensis. From 173,487 V6 sequences, 6,733 coral- and 1,052 water-associated operational taxonomic units (OTUs) were observed. M. braziliensis microbiota was more similar across reefs than to other Mussismilia species microbiota from the same reef. Highly prevalent OTUs were more significantly structured by coral lineage and were enriched in Alpha- and Gammaproteobacteria. Bacterial OTUs from healthy corals were recovered from a M. braziliensis skeleton sample at twice the frequency of recovery from water or a diseased coral suggesting the skeleton is a significant habitat for microbial populations in the holobiont. Diseased corals were enriched with pathogens and opportunists (Vibrios, Bacteroidetes, Thalassomonas, and SRB). Our study examines for the first time intra- and inter-specific variability of microbiota across the genus Mussismilia. Changes in microbiota may be useful indicators of coral health and thus be a valuable tool for coral reef management and conservation. PMID:25213651

Fernando, Samodha C; Wang, Jia; Sparling, Kimberly; Garcia, Gizele D; Francini-Filho, Ronaldo B; de Moura, Rodrigo L; Paranhos, Rodolfo; Thompson, Fabiano L; Thompson, Janelle R

2015-02-01

309

Can artificial reefs mimic natural reef communities? The roles of structural features and age  

Microsoft Academic Search

In light of the deteriorating state of coral reefs worldwide, the need to rehabilitate marine environments has greatly increased. Artificial reefs (ARs) have been suggested as a tool for reef conservation and rehabilitation. Although successions of AR communities have been thoroughly studied, current understanding of the interactions between artificial and natural reefs (NRs) is poor and a fundamental question still

S. Perkol-Finkel; N. Shashar; Y. Benayahu

2006-01-01

310

Distribution, abundance, and substrate preferences of demersal reef zooplankton at Lizard Island Lagoon, Great Barrier Reef  

Microsoft Academic Search

Demersal zooplankton, those plankton which hide within reef sediments during the day but emerge to swim freely over the reef at night, were sampled quantitatively using emergence traps planced over the substrate at Lizard Island Lagoon, Great Barrier Reef. Densities of zooplankton emerging at night from 6 substrate types (fine, medium, and coarse sand, rubble, living coral and reef rock)

A. L. Alldredge; J. M. King

1977-01-01

311

ORIGINAL ARTICLE Black reefs: iron-induced phase shifts on coral reefs  

E-print Network

ORIGINAL ARTICLE Black reefs: iron-induced phase shifts on coral reefs This article has been, Australia The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions surveys show that the live coral cover was reduced from 40 to 60% to o10% on black reefs on Millennium

Smith, Jennifer E.

312

112 National Coral Reef Action Strategy CORAL REEF CONSERVATION ACT OF 2000  

E-print Network

management and sustainable use of coral reef ecosystems to benefit local communities and the Nation; (3 Reef Action Strategy APPENDIX A CORAL REEF CONSERVATION ACT OF 2000 [P.L. 106-562; 16 U.S.C. 6401 et seq; December 23, 2000] TITLE II--CORAL REEF CONSERVATION SEC. 201. SHORT TITLE. This title may

313

A Night in the Coral Reef  

NSDL National Science Digital Library

Coral reefs are often portrayed as brightly lit, bustling underwater marvels full of colorful creatures. This video segment, adapted from NOVA, paints a different picture as it explores the nocturnal behavior of organisms in the reef.

2007-04-19

314

Ocean acidification worse in coral reefs  

NASA Astrophysics Data System (ADS)

The rate of ocean acidification in coral reefs outpaces the rise in carbon dioxide (CO2) in Earth's atmosphere, indicating that anthropogenic carbon emissions alone are not to blame for the threat to coral reefs, a new study shows.

Betz, Eric O.

2014-12-01

315

Call to protect all coral reefs  

NASA Astrophysics Data System (ADS)

The world's coral reefs are in decline, threatening the food security of millions of people. Adopting an ecosystem-scale approach that protects deep as well as shallow reefs would deliver several social and economic benefits.

Bridge, Tom C. L.; Hughes, Terry P.; Guinotte, John M.; Bongaerts, Pim

2013-06-01

316

Reef Squid at USGS Monitoring Station  

USGS Multimedia Gallery

A curious reef squid hovers over a calcification-monitoring station used to measure calcification rates to determine impact of ocean acidification on coral growth at Fowey Rocks Light Reef in Biscayne National Park.  ...

317

Coral Reef Fishes: Opportunities, Challenges and Concerns  

Microsoft Academic Search

\\u000a Coral reef fishes represent superb models for test of biological theory in field or laboratory. Nonetheless, our knowledge\\u000a comes from few locations, few biological disciplines, and few of the more than 70 families of fishes occupying coral reefs.\\u000a Most reef fishes exhibit complex life histories involving distinctive pelagic larval stages, ecological and structural changes\\u000a associated with settling on reefs, and

W. Linn Montgomery

318

Development and implementation of coral reef biocriteria in U.S. jurisdictions.  

PubMed

Coral reefs worldwide are declining at an alarming rate and are under continuous threat from both natural and anthropogenic environmental stressors. Warmer sea temperatures attributed to global climate change and numerous human activities at local scales place these valuable ecosystems at risk. Reefs provide numerous services, including shoreline protection, fishing, tourism and biological diversity, which are lost through physical damage, overfishing, and pollution. Pollution can be controlled under provisions of the Clean Water Act, but these options have not been fully employed to protect coral reefs. No U.S. jurisdiction has implemented coral reef biocriteria, which are narrative or quantitative water quality standards based on the condition of a biological resource or assemblage. The President's Ocean Action Plan directs the U.S. Environmental Protection Agency (EPA) to develop biological assessment methods and biological criteria for evaluating and maintaining the health of coral reef ecosystems. EPA has formed the Coral Reef Biocriteria Working Group (CRBWG) to foster development of coral reef biocriteria through focused research, evaluation and communication among Agency partners and U.S. jurisdictions. Ongoing CRBWG activities include development and evaluation of a rapid bioassessment protocol for application in biocriteria programs; development of a survey design and monitoring strategy for the U.S. Virgin Islands; comprehensive reviews of biocriteria approaches proposed by states and territories; and assembly of data from a variety of monitoring programs for additional metrics. Guidance documents are being prepared to assist U.S. jurisdictions in reaching protective and defensible biocriteria. PMID:19052888

Bradley, Patricia; Fisher, William S; Bell, Heidi; Davis, Wayne; Chan, Valerie; LoBue, Charles; Wiltse, Wendy

2009-03-01

319

Lab 1: Coral Reefs, the Human View  

NSDL National Science Digital Library

Students are introduced to coral reef ecosystems and the importance of corals to humans. Students watch the IMAX film Coral Reef Adventure to experience the human view of coral reefs through the eyes of ocean explorers and underwater filmmakers Howard and Michele Hall. The students then use microscopes to examine coral and identify its features.

320

PHOSPHATE METABOLISM OF CORAL REEF FLATS  

E-print Network

PHOSPHATE METABOLISM OF CORAL REEF FLATS A DISSERTATION SUBMITTED TO THE GRADUATE DIVISION. Chave Edward A. Laws David M. Karl Robert L. Fox #12;iv ABSTRACT Ihe present dogma on coral reef overlying that community. The reef's nutritional requirements supposedly are met by cycling or retention

Luther, Douglas S.

321

The future of coral reefs Nancy Knowlton*  

E-print Network

Colloquium The future of coral reefs Nancy Knowlton* Marine Biology Research Division 0202, Scripps Tropical Research Institute, Apartado 2072, Balboa, Republic of Panama Coral reefs, with their millions communities, and coral death. (iv) The activities of people near reefs increase both fishing pressure

Bermingham, Eldredge

322

40 CFR 230.44 - Coral reefs.  

Code of Federal Regulations, 2011 CFR

... 25 2011-07-01 2011-07-01 false Coral reefs. 230.44 Section 230.44 Protection of...Impacts on Special Aquatic Sites § 230.44 Coral reefs. (a) Coral reefs consist of the skeletal deposit, usually...

2011-07-01

323

MFR PAPER 1183 Helen Reef's large tridacnid  

E-print Network

MFR PAPER 1183 Helen Reef's large tridacnid clams have declined sharply in recent years. Status of Giant Clam Stocks (Tridacnidae) on Helen Reef, Palau, Western Caroline Islands, April 1975 Philippines,800 m2 were covered in transects made on Helen Reef to assess population levels of Tridacnidae

324

Coral Reefs and Their Management in Tanzania  

Microsoft Academic Search

Coral reefs are very important in Tanzania, both ecologically and socio-economically, as major fishing grounds and tourist attractions. Numerous fringing and patch reefs are located along about two-thirds of Tanzania's coastline. These reefs have been partially to severely degraded by human (primarily destructive fishing practices) and natural (particularly coral bleaching) causes. These immediate human causes have been brought about by

Greg M. Wagner

325

The Pros and Cons of Artificial Reefs  

NSDL National Science Digital Library

This lesson plan asks students to consider whether artificial reefs (human-made objects in the ocean or sea) are good for marine ecosystems. Students will look at pictures of artificial reefs and read articles describing the pros and cons of these structures. They will conclude by writing paragraphs explaining whether they think a new artificial reef should be created in Florida waters.

326

Early survivorship of juvenile coral reef fishes  

Microsoft Academic Search

Data on early survivorship of newly settled reef fish were collected by monitoring individuals which recruited to 30 small lagoonal patch reefs over three summers. Preliminary survivorship curves spanning the first 45 days after settlement were derived for 17 species. Most species showed greatest rates of mortality in the first 1–2 weeks in the reef environment however there were substantial

Peter F. Sale; Douglas J. Ferrell

1988-01-01

327

Assessing Coral Reef Condition: Eliciting Community Meanings  

Microsoft Academic Search

Photographs depicting a gradient of coral reef condition associated with anchor damage were assessed and described by 76 research participants. The participants were divided into two groups: those with and those without occupational experience of coral reefs. Three important meanings ascribed to coral reefs were elicited. The most important meaning was “evaluation,” whether the scenes were perceived positively or negatively.

Elizabeth A. Dinsdale; D. Mark Fenton

2006-01-01

328

Coral Reef Conservation: A Reef of Your Own  

NSDL National Science Digital Library

This web-based lesson focuses on the physiological, ecological, and behavioral strategies that contribute to the success of reef-building corals. Students will learn to describe and explain the importance of asexual and sexual reproductive strategies to reef-building corals, why it is important that the corals have a nutritional strategy that includes both photosynthesis and carnivory, two behaviors that they use to compete for living space with other species, and how coral reefs can produce high levels of biological material when the waters surround­ing them contain relatively small amounts of the nutri­ents normally needed to support biological production. Links to the required online resources are provided.

2011-08-23

329

Acquiring multiple stars with the LINC-NIRVANA Pathfinder  

NASA Astrophysics Data System (ADS)

The LINC-NIRVANA Pathfinder1 (LN-PF), a ground-layer adaptive optics (AO) system recently commissioned at the Large Binocular Telescope (LBT), is one of 4 sensors that provide AO corrected images to the full LINC-NIRVANA instrument. With first light having taken place on November 17, 2013,2, 3 the core goals for the LN-PF have been accomplished. In this report, we look forward to one of the LN-PF extended goals. In particular, we review the acquisition mechanism required to place each of several star probes on its corresponding star in the target asterism. For emerging AO systems in general, co-addition of light from multiple stars stands as one of several methods being pursued to boost sky coverage. With 12 probes patrolling a large field of view (an annulus 6-arcminutes in diameter), the LN-PF will provide a valuable testbed to verify this method.

Conrad, Albert R.; Arcidiacono, Carmelo; Baumeister, Harald; Bergomi, Maria; Bertram, Thomas; Berwein, Jürgen; Briegel, Florian; Farinato, Jacopo; Herbst, Tom; Hofferbert, Ralph; Kittmann, Frank; Kürster, Martin; Kopon, Derek; Marafatto, Luca; Norris, Mark; Ragazzoni, Roberto; Viotto, Valentina

2014-08-01

330

Exploring MEDLINE space with random indexing and pathfinder networks.  

PubMed

The integration of disparate research domains is a prerequisite for the success of the translational science initiative. MEDLINE abstracts contain content from a broad range of disciplines, presenting an opportunity for the development of methods able to integrate the knowledge they contain. Latent Semantic Analysis (LSA) and related methods learn human-like associations between terms from unannotated text. However, their computational and memory demands limits their ability to address a corpus of this size. Furthermore, visualization methods previously used in conjunction with LSA have limited ability to define the local structure of the associative networks LSA learns. This paper explores these issues by (1) processing the entire MEDLINE corpus using Random Indexing, a variant of LSA, and (2) exploring learned associations using Pathfinder Networks. Meaningful associations are inferred from MEDLINE, including a drug-disease association undetected by PUBMED search. PMID:18999236

Cohen, Trevor

2008-01-01

331

Prediction and Validation of Mars Pathfinder Hypersonic Aerodynamic Data Base  

NASA Technical Reports Server (NTRS)

Postflight analysis of the Mars Pathfinder hypersonic, continuum aerodynamic data base is presented. Measured data include accelerations along the body axis and axis normal directions. Comparisons of preflight simulation and measurements show good agreement. The prediction of two static instabilities associated with movement of the sonic line from the shoulder to the nose and back was confirmed by measured normal accelerations. Reconstruction of atmospheric density during entry has an uncertainty directly proportional to the uncertainty in the predicted axial coefficient. The sensitivity of the moment coefficient to freestream density, kinetic models and center-of-gravity location are examined to provide additional consistency checks of the simulation with flight data. The atmospheric density as derived from axial coefficient and measured axial accelerations falls within the range required for sonic line shift and static stability transition as independently determined from normal accelerations.

Gnoffo, Peter A.; Braun, Robert D.; Weilmuenster, K. James; Mitcheltree, Robert A.; Engelund, Walter C.; Powell, Richard W.

1998-01-01

332

Cerberus Plains: A most excellent Pathfinder landing site  

NASA Technical Reports Server (NTRS)

The Cerberus Plains in southeastern Elysium and western Amazonis cover greater than 10(exp 5) sq km, extending an east-west distance of approximately 3000 km and a north-south distance of up to 700 km near 195 deg. Crater numbers are 89 plus or minus 15 craters greater than 1 km/10(exp 6) sq km, indicating a stratigraphic age of Upper Amazonian and an absolute age of 200-500 Ma. The material forming the surface is referred to as the Cerberus Formation. The two ideas postulated about the unit's origin are fluvial and volcanic. Regardless of which interpretation is correct, the Cerberus Plains is an important candidate for a pathfinder landing site because it represents the youngest major geologic event (be it fluvial or volcanic) on Mars.

Plescia, Jeff B.

1994-01-01

333

Dust devil vortices seen by the Mars Pathfinder camera  

USGS Publications Warehouse

Discovery of dust devil vortices in Mars Pathfinder (MPF) images reveals a dust entrainment mechanism at work on Mars. Scattering of visible light by dust in the Martian atmosphere creates a pronounced haze, preventing conventional image processing from displaying dust plumes. Spectral differencing techniques have enhanced five localized dust plumes from the general haze in images acquired near midday, which we determine to be dust devils. Processing of 440 nm images highlights dust devils as distinct occultation features against the horizon. The dust devils are interpreted to be 14-79 m wide, 46-350 m tall, travel at 0.5-4.6 m/s, with dust loading of 7E-5 kg m-3, relative to the general haze of 9E-8 kg m-3, and total particulate transport of 2.2 - 700 kg. The vortices match predictions from terrestrial analog studies. Copyright 1999 by the American Geophysical Union.

Metzger, S.M.; Carr, J.R.; Johnson, J.R.; Parker, T.J.; Lemmon, M.T.

1999-01-01

334

State space modelling and data analysis exercises in LISA Pathfinder  

E-print Network

LISA Pathfinder is a mission planned by the European Space Agency to test the key technologies that will allow the detection of gravitational waves in space. The instrument on-board, the LISA Technology package, will undergo an exhaustive campaign of calibrations and noise characterisation campaigns in order to fully describe the noise model. Data analysis plays an important role in the mission and for that reason the data analysis team has been developing a toolbox which contains all the functionalities required during operations. In this contribution we give an overview of recent activities, focusing on the improvements in the modelling of the instrument and in the data analysis campaigns performed both with real and simulated data.

Nofrarias, M; Armano, M; Audley, H; Auger, G; Benedetti, M; Binetruy, P; Bogenstahl, J; Bortoluzzi, D; Bosetti, P; Brandt, N; Caleno, M; Cañizares, P; Cavalleri, A; Cesa, M; Chmeissani, M; Conchillo, A; Congedo, G; Cristofolin, I; Cruise, M; Danzmann, K; De Marchi, F; Diaz-Aguilo, M; Diepholz, I; Dixon, G; Dolesi, R; Dunbar, N; Fauste, J; Ferraioli, L; Fichter, V Ferroni W; Fitzsimons, E; Freschi, M; Marin, A García; Marirrodriga, C García; Gesa, R Gerndt L; Gibert, F; Giardini, D; Grimani, C; Grynagier, A; Guillaume, B; Guzmán, F; Harrison, I; Heinzel, G; Hernández, V; Hewitson, M; Hollington, D; Hough, J; Hoyland, D; Hueller, M; Huesler, J; Jennrich, O; Jetzer, P; Johlander, B; Killow, C; Llamas, X; Lloro, I; Lobo, A; Maarschalkerweerd, R; Madden, S; Mance, D; Mateos, I; McNamara, P W; Mendes, J; Mitchell, E; Monsky, A; Nicolini, D; Nicolodi, D; Pedersen, F; Perreur-Lloyd, M; Plagnol, E; Prat, P; Racca, G D; Ramos-Castro, J; Reiche, J; Perez, J A Romera; Robertson, D; Rozemeijer, H; Sanjuan, J; Schleicher, A; Schulte, M; Shaul, D; Stagnaro, L; Strandmoe, S; Steier, F; Sumner, T J; Taylor, A; Texier, D; Trenkel, C; Vitale, H-B Tu S; Wanner, G; Ward, H; Waschke, S; Wass, P; Weber, W J; Ziegler, T; Zweifel, P

2013-01-01

335

State space modelling and data analysis exercises in LISA Pathfinder  

E-print Network

LISA Pathfinder is a mission planned by the European Space Agency to test the key technologies that will allow the detection of gravitational waves in space. The instrument on-board, the LISA Technology package, will undergo an exhaustive campaign of calibrations and noise characterisation campaigns in order to fully describe the noise model. Data analysis plays an important role in the mission and for that reason the data analysis team has been developing a toolbox which contains all the functionalities required during operations. In this contribution we give an overview of recent activities, focusing on the improvements in the modelling of the instrument and in the data analysis campaigns performed both with real and simulated data.

M Nofrarias; F Antonucci; M Armano; H Audley; G Auger; M Benedetti; P Binetruy; J Bogenstahl; D Bortoluzzi; N Brandt; M Caleno; A Cavalleri; G Congedo; M Cruise; K Danzmann; F De Marchi; M Diaz-Aguilo; I Diepholz; G Dixon; R Dolesi; N Dunbar; J Fauste; L Ferraioli; V Ferroni W Fichter; E Fitzsimons; M Freschi; C García Marirrodriga; R Gerndt; L Gesa; F Gibert; D Giardini; C Grimani; A Grynagier; F Guzmán; I Harrison; G Heinzel; M Hewitson; D Hollington; D Hoyland; M Hueller; J Huesler; O Jennrich; P Jetzer; B Johlander; N Karnesis; N Korsakova; C Killow; X Llamas; I Lloro; A Lobo; R Maarschalkerweerd; S Madden; D Mance; I Mateos; P W McNamara; J Mendes; E Mitchell; D Nicolini; D Nicolodi; M Perreur-Lloyd; E Plagnol; P Prat; J Ramos-Castro; J Reiche; J A Romera Perez; D Robertson; H Rozemeijer; G Russano; A Schleicher; D Shaul; CF Sopuerta; T J Sumner; A Taylor; D Texier; C Trenkel; H-B Tu; S Vitale; G Wanner; H Ward; S Waschke; P Wass; D Wealthy; S Wen; W J Weber; T Ziegler; P Zweifel

2013-06-21

336

Soil-like deposits observed by Sojourner, the Pathfinder rover  

USGS Publications Warehouse

Most of the soil-like materials at the Pathfinder landing site behave like moderately dense soils on Earth with friction angles near 34°-39° and are called cloddy deposits. Cloddy deposits appear to be poorly sorted with dust-sized to granule-sized mineral or rock grains; they may contain pebbles, small rock fragments, and clods. Thin deposits of porous, compressible drifts with friction angles near 26°-28° are also present. Drifts are fine grained. Cohesions of both types of deposits are small. There may be indurated soil-like deposits and/or coated or crusted rocks. Cloddy deposits may be fluvial sediments of the Ares-Tiu floods, but other origins, such as ejecta from nearby impact craters, should be considered. Drifts are probably dusts that settled from the Martian atmosphere. Remote-sensing signatures of the deposits inferred from rover observations are consistent with those observed from orbit and Earth.

Moore, Henry J.; Bickler, Donald B.; Crisp, Joy A.; Eisen, Howard J.; Gensler, Jeffrey A.; Haldemann, Albert F.C.; Matijevic, Jacob R.; Reid, Lisa K.; Pavlics, Ferenc

1999-01-01

337

Mars Pathfinder and the exploration of southern Amazonis Planitia  

NASA Technical Reports Server (NTRS)

The southern region of Amazonis Planitia provides a variety of target terrains for a roving vehicle such as the Mars Pathfinder Mission. A landing site is proposed at 4 deg N latitude 162 deg W longitude. This area has a reference altitude of between 0 and -1 km and consists of relatively smooth Amazonian-aged deposits within the entire 100 x 200 km landing ellipse. The proposed landing site is within the Upper Member Medusae Fossae Formation deposits (Amu) and near the boundary with Middle Member Medusae Fossae Formation deposits (Amm) and Member 1 Arcadia Formation plains (Aa(sub 1)). Slightly further afield are 107-km-diameter Nicholson crater, its ejecta deposits, and knobby terrain of proposed Hesperian age (HNu). Depending on the exact landing site of the spacecraft and the traverse distance of the rover, these materials also may be sampled.

Barlow, Nadine G.

1994-01-01

338

Aeolian features and processes at the Mars Pathfinder landing site  

USGS Publications Warehouse

The Mars Pathfinder landing site contains abundant features attributed to aeolian, or wind, processes. These include wind tails, drift deposits, duneforms of various types, ripplelike features, and ventifacts (the first clearly seen on Mars). Many of these features are consistant with formation involving sand-size particles. Although some features, such as dunes, could develop from saltating sand-size aggregates of finer grains, the discovery of ventifact flutes cut in rocks strongly suggests that at least some of the grains are crystalline, rather than aggregates. Excluding the ventifacts, the orientations of the wind-related features correlate well with the orientations of bright wind steaks seen on Viking Orbiter images in the general area. They also correlate with wind direction predictions from the NASA-Ames General Circulation Model (GCM) which show that the strongest winds in the area occur in the northern hemisphere winter and are directed toward 209°. Copyright 1999 by the American Geophysical Union.

Greeley, Ronald; Kraft, Michael; Sullivan, Robert; Wilson, Gregory; Bridges, Nathan; Herkenhoff, Ken; Kuzmin, Ruslan O.; Malin, Michael; Ward, Wes

1999-01-01

339

Drill/borescope System for the Mars Polar Pathfinder  

NASA Technical Reports Server (NTRS)

The primary goals of the Mars Polar Pathfinder (MPP) Discovery Mission are to characterize the composition and structure of Mars' north polar ice cap, and to determine whether a climate record may be preserved in layers of ice and dust. The MPP would land as close as possible to the geographic north pole of Mars and use a set of instruments similar to those used by glaciologists to study polar ice caps on Earth: a radar sounder, a drill/borescope system, and a thermal probe. The drill/borescope system will drill approximately 50 cm into the surface and image the sides of the hole at 10 micron resolution for compositional and stratigraphic analysis. Several uncertainties have guided the development of this instrument, and they are discussed.

Paige, D. A.; Wood, S. E.; Vasavada, A. R.

1993-01-01

340

Wake Flow About the Mars Pathfinder Entry Vehicle  

NASA Technical Reports Server (NTRS)

A computational approach is used to describe the aerothermodynamics of the Mars Pathfinder vehicle entering the Mars atmosphere at the maximum heating and maximum deceleration points in its trajectory. Ablating and nonablating boundary conditions are developed which produce maximum recombination of CO2 on the surface. For the maximum heating trajectory point, an axisymmetric, nonablating calculation predicts a stagnation-point value for the convective heating of 115 W/cm(exp 2). Radiative heating estimates predict an additional 5-12 W/cm(exp 2) at the stagnation point. Peak convective heating on the afterbody occurs on the vehicle's flat stern with a value of 5.9% of the stagnation value. The forebody flow exhibits chemical nonequilibrium behavior, and the flow is frozen in the near wake. Including ablation injection on the forebody lowers the stagnation-point convective heating 18%.

Mitcheltree, R. A.; Gnoffo, P. A.

1995-01-01

341

Wheel Abrasion Experiment Metals Selection for Mars Pathfinder Mission  

NASA Technical Reports Server (NTRS)

A series of metals was examined for suitability for the Wheel Abrasion Experiment, one of ten microrover experiments of the Mars Pathfinder Mission. The seven candidate metals were: Ag, Al, Au, Cu, Ni, Pt, and W. Thin films of candidate metals from 0.1 to 1.0 micrometer thick were deposited on black anodized aluminum coupons by e-beam and resistive evaporation and chemical vapor deposition. Optical, corrosion, abrasion, and adhesion criteria were used to select Al, Ni, and Pt. A description is given of the deposition and testing of thin films, followed by a presentation of experimental data and a brief discussion of follow-on testing and flight qualification.

Hepp, Aloysius F.; Fatemi, Navid S.; Wilt, David M.; Ferguson, Dale C.; Hoffman, Richard; Hill, Maria M.; Kaloyeros, Alain E.

1996-01-01

342

The LISA Pathfinder interferometry—hardware and system testing  

NASA Astrophysics Data System (ADS)

Preparations for the LISA Pathfinder mission have reached an exciting stage. Tests of the engineering model (EM) of the optical metrology system have recently been completed at the Albert Einstein Institute, Hannover, and flight model tests are now underway. Significantly, they represent the first complete integration and testing of the space-qualified hardware and are the first tests on an optical system level. The results and test procedures of these campaigns will be utilized directly in the ground-based flight hardware tests, and subsequently during in-flight operations. In addition, they allow valuable testing of the data analysis methods using the MATLAB-based LTP data analysis toolbox. This paper presents an overview of the results from the EM test campaign that was successfully completed in December 2009.

Audley, H.; Danzmann, K.; García Marín, A.; Heinzel, G.; Monsky, A.; Nofrarias, M.; Steier, F.; Gerardi, D.; Gerndt, R.; Hechenblaikner, G.; Johann, U.; Luetzow-Wentzky, P.; Wand, V.; Antonucci, F.; Armano, M.; Auger, G.; Benedetti, M.; Binetruy, P.; Boatella, C.; Bogenstahl, J.; Bortoluzzi, D.; Bosetti, P.; Caleno, M.; Cavalleri, A.; Cesa, M.; Chmeissani, M.; Ciani, G.; Conchillo, A.; Congedo, G.; Cristofolini, I.; Cruise, M.; De Marchi, F.; Diaz-Aguilo, M.; Diepholz, I.; Dixon, G.; Dolesi, R.; Fauste, J.; Ferraioli, L.; Fertin, D.; Fichter, W.; Fitzsimons, E.; Freschi, M.; García Marirrodriga, C.; Gesa, L.; Gibert, F.; Giardini, D.; Grimani, C.; Grynagier, A.; Guillaume, B.; Guzmán, F.; Harrison, I.; Hewitson, M.; Hollington, D.; Hough, J.; Hoyland, D.; Hueller, M.; Huesler, J.; Jeannin, O.; Jennrich, O.; Jetzer, P.; Johlander, B.; Killow, C.; Llamas, X.; Lloro, I.; Lobo, A.; Maarschalkerweerd, R.; Madden, S.; Mance, D.; Mateos, I.; McNamara, P. W.; Mendes, J.; Mitchell, E.; Nicolini, D.; Nicolodi, D.; Pedersen, F.; Perreur-Lloyd, M.; Perreca, A.; Plagnol, E.; Prat, P.; Racca, G. D.; Rais, B.; Ramos-Castro, J.; Reiche, J.; Romera Perez, J. A.; Robertson, D.; Rozemeijer, H.; Sanjuan, J.; Schulte, M.; Shaul, D.; Stagnaro, L.; Strandmoe, S.; Sumner, T. J.; Taylor, A.; Texier, D.; Trenkel, C.; Tombolato, D.; Vitale, S.; Wanner, G.; Ward, H.; Waschke, S.; Wass, P.; Weber, W. J.; Zweifel, P.

2011-05-01

343

Exploring MEDLINE Space with Random Indexing and Pathfinder Networks  

PubMed Central

The integration of disparate research domains is a prerequisite for the success of the translational science initiative. MEDLINE abstracts contain content from a broad range of disciplines, presenting an opportunity for the development of methods able to integrate the knowledge they contain. Latent Semantic Analysis (LSA) and related methods learn human-like associations between terms from unannotated text. However, their computational and memory demands limits their ability to address a corpus of this size. Furthermore, visualization methods previously used in conjunction with LSA have limited ability to define the local structure of the associative networks LSA learns. This paper explores these issues by (1) processing the entire MEDLINE corpus using Random Indexing, a variant of LSA, and (2) exploring learned associations using Pathfinder Networks. Meaningful associations are inferred from MEDLINE, including a drug-disease association undetected by PUBMED search. PMID:18999236

Cohen, Trevor

2008-01-01

344

Miocene reefs of Dominican Republic  

SciTech Connect

The reefs are overlain by conglomeratic strata. The stratigraphic setting of these reefs suggests that they have developed along the stalled portions of rapidly prograding fan deltas. Thickets and layers of coral debris are found seaward and stratigraphically above the well-developed reef. The matrix sediments are exclusively fine-grained sand to mud, and the fauna are suggestive of more open shelf conditions. In thickets, branched (porites spp., Pocillopora spp.), small massive (Montastrea spp., Siderastrea spp.), and foliose or plate like (Agaricia spp.) corals are found upright in the muddy sediment. Similarities in coral species and areal proximity suggest that thickets are the source of most layers of coralline debris. The association of coral debris with graded bedding and cross-bedding suggests that coral debris has been reworked by storms. The growth of corals and development of coral reefs in the Miocene-Pliocene Yaque Group is limited only by opportunities created by the slowing of siliciclastic sedimentation. Soft, muddy, terrigenous substrates and a continuing supply of terrigenous mud exert only a limited, indirect effect on reef growth.

Evans, C.C.

1988-01-01

345

Techniques for identifying dust devils in mars pathfinder images  

USGS Publications Warehouse

Image processing methods used to identify and enhance dust devil features imaged by IMP (Imager for Mars Pathfinder) are reviewed. Spectral differences, visible red minus visible blue, were used for initial dust devil searches, driven by the observation that Martian dust has high red and low blue reflectance. The Martian sky proved to be more heavily dust-laden than pre-Pathfinder predictions, based on analysis of images from the Hubble Space Telescope. As a result, these initial spectral difference methods failed to contrast dust devils with background dust haze. Imager artifacts (dust motes on the camera lens, flat-field effects caused by imperfections in the CCD, and projection onto a flat sensor plane by a convex lens) further impeded the ability to resolve subtle dust devil features. Consequently, reference images containing sky with a minimal horizon were first subtracted from each spectral filter image to remove camera artifacts and reduce the background dust haze signal. Once the sky-flat preprocessing step was completed, the red-minus-blue spectral difference scheme was attempted again. Dust devils then were successfully identified as bright plumes. False-color ratios using calibrated IMP images were found useful for visualizing dust plumes, verifying initial discoveries as vortex-like features. Enhancement of monochromatic (especially blue filter) images revealed dust devils as silhouettes against brighter background sky. Experiments with principal components transformation identified dust devils in raw, uncalibrated IMP images and further showed relative movement of dust devils across the Martian surface. A variety of methods therefore served qualitative and quantitative goals for dust plume identification and analysis in an environment where such features are obscure.

Metzger, S.M.; Carr, J.R.; Johnson, J.R.; Parker, T.J.; Lemmon, M.T.

2000-01-01

346

Two Pathfinder Tests of High Precision Astrometry On-Sky  

NASA Astrophysics Data System (ADS)

MCAO systems on ELTs should deliver the best available relative astrometric precision from the ground, which may be sufficient to detect exo-earths orbiting nearby brown and red dwarfs (< 0.03 mas). Yet despite the success of AO astrometry on large telescopes, we still do not understand the systematic errors that may dominate long-term astrometric stability with MCAO, such as dynamic optical distortion and differential atmospheric refraction (DAR). We present results from two on-sky pathfinders intended to characterize long-term systematic errors in MCAO systems and discuss implications for MCAO on ELTs. The first is an astrometric monitoring program of bright stars in 2013A on the GEMS LGS MCAO system. We isolate the effects of dynamic optical distortion by using narrow filters to counter atmospheric refraction and observing sparse fields to avoid crowding errors. We characterize the magnitude of long-term optical drift in GEMs as well as the dependency on the number of NGSs used. The second pathfinder is an on-sky test of the diffractive pupil concept on a 1-meter telescope at Lick Observatory, theorized to calibrate changing optical distortion with diffracted light from the target star (Guyon et al. 2012). These data indicate PSF modeling systematics of one thousandth of the star FWHM (1 mas) for individual stars, but we show that averaging the many diffracted PSFs reduces this error and other flat-fielding errors to the ~0.5 mas level. We show that the diffractive pupil stabilizes the instrumental distortion to at least the precision of the experiment (~1 mas over 3'). We simulate the astrometric performance of a hybrid MCAO + diffractive pupil system on ELTs. The diffracted PSFs include an anisoplanatic term, increasing PSF modeling errors, but the sum of all random errors (CDAR, DAR, DTTJ, S/N) can be better than 0.01 mas for 5 minute exposures for K < 15 stars.

Ammons, S. Mark; Bendek, Eduardo; Guyon, Olivier; Macintosh, Bruce; Marois, Christian; Neichel, Benoit; Galicher, Raphael; Savransky, Dimitri

2013-12-01

347

Inflight magnetic characterization of the test masses onboard LISA Pathfinder  

NASA Astrophysics Data System (ADS)

Laser Interferometer Space Antenna (LISA) Pathfinder is a science and technology demonstrator of the European Space Agency within the framework of its LISA mission, the latter aiming to be the first space-borne gravitational wave observatory. The payload of LISA Pathfinder is the so-called LISA Technology Package, which is designed to measure relative accelerations between two test masses in nominal free fall. The diagnostics subsystem consists of several modules, one of which is the magnetic diagnostics unit. Its main function is the assessment of the differential acceleration noise between the test masses due to magnetic effects. This subsystem is composed of two onboard coils intended to produce controlled magnetic fields at the location of the test masses. These magnetic fields couple with the remanent magnetic moment and susceptibility and produce forces and torques on the test masses. These, in turn, produce kinematic excursions of the test masses which are sensed by the onboard interferometer. We prove that adequately processing these excursions, the magnetic properties of the test masses can be estimated using classical multiparameter estimation techniques. Moreover, we show that special processing procedures to minimize the effect of the multichannel cross-talks are needed. Finally, we demonstrate that the quality of our estimates is frequency-dependent. We also suggest that using a multiple frequency experiment, the global estimate can be obtained in such a way that the results of the magnetic experiment are more reliable. Finally, using our procedure, we compute the contribution of the magnetic noise to the total proof-mass acceleration noise.

Diaz-Aguiló, Marc; García-Berro, Enrique; Lobo, Alberto

2012-02-01

348

Inflight magnetic characterization of the test masses onboard LISA Pathfinder  

E-print Network

LISA Pathfinder is a science and technology demonstrator of the European Space Agency within the framework of its LISA mission, the latter aiming to be the first space-borne gravitational wave observatory. The payload of LISA Pathfinder is the so-called LISA Technology Package, which is designed to measure relative accelerations between two test masses in nominal free fall. The diagnostics subsystem consists of several modules, one of which is the magnetic diagnostics unit. Its main function is the assessment of the differential acceleration noise between the test masses due to magnetic effects. This subsystem is composed of two onboard coils intended to produce controlled magnetic fields at the location of the test masses. These magnetic fields couple with the remanent magnetic moment and susceptibility and produce forces and torques on the test masses. These, in turn, produce kinematic excursions of the test masses which are sensed by the onboard interferometer. We prove that adequately processing these excursions, the magnetic properties of the test masses can be estimated using classical multi-parameter estimation techniques. Moreover, we show that special processing procedures to minimize the effect of the multi channel cross-talks are needed. Finally, we demonstrate that the quality of our estimates is frequency dependent. We also suggest that using a multiple frequency experiment the global estimate can be obtained in such a way that the results of the magnetic experiment are more reliable. Finally, using our procedure we compute the the contribution of the magnetic noise to the total proof-mass acceleration noise.

Marc Diaz-Aguiló; Enrique García-Berro; Alberto Lobo

2012-02-13

349

Coral reef crisis in deep and shallow reefs: 30 years of constancy and change in reefs of Curacao and Bonaire  

NASA Astrophysics Data System (ADS)

Coral reefs are thought to be in worldwide decline but available data are practically limited to reefs shallower than 25 m. Zooxanthellate coral communities in deep reefs (30-40 m) are relatively unstudied. Our question is: what is happening in deep reefs in terms of coral cover and coral mortality? We compare changes in species composition, coral mortality, and coral cover at Caribbean (Curacao and Bonaire) deep (30-40 m) and shallow reefs (10-20 m) using long-term (1973-2002) data from permanent photo quadrats. About 20 zooxanthellate coral species are common in the deep-reef communities, dominated by Agaricia sp., with coral cover up to 60%. In contrast with shallow reefs, there is no decrease in coral cover or number of coral colonies in deep reefs over the last 30 years. In deep reefs, non-agaricid species are decreasing but agaricid domination will be interrupted by natural catastrophic mortality such as deep coral bleaching and storms. Temperature is a vastly fluctuating variable in the deep-reef environment with extremely low temperatures possibly related to deep-reef bleaching.

Bak, Rolf P. M.; Nieuwland, Gerard; Meesters, Erik H.

2005-11-01

350

Old Desert Varnish-like Coatings and Young Breccias at the Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

Many rocks at the Mars Pathfinder landing site exhibit evidence for desert varnish-like coatings that formed during an early, moist climate. Later eolian erosion partly stripped the coatings. Rocks excavated subsequently have shapes consistent with breccias or conglomerates.

Murchie, S.; Barnouin-Jha, O.; Barnouin-Jha, K.; Bishop, J.; Johnson, J.; McSween, H.; Morris, R.

2004-01-01

351

PATHFINDER REVIEW COMMITTEE FINAL REPORT Presented to UC Berkeley Library Cabinet  

E-print Network

Pathfinder Features D. Position Paper from Library Sciences Council E. The UC Davis experience: statement with members of the Arts and Humanities and the Social Sciences councils. The Library Sciences Council provided

California at Berkeley, University of

352

Gambling on the Protestants: the Pathfinder Fund and birth control in Peru, 1958-1965.  

PubMed

Among the agencies involved in population control activities in the mid-twentieth century, none scored as many early victories in Latin America as did the Pathfinder Fund, founded by Procter & Gamble scion Clarence Gamble. This article analyzes a style in the delivery of family planning assistance in the developing world through the work of the Pathfinder Fund in Peru, the organization's hub in South America, and shows how Pathfinder personnel collaborated with local Protestant institutions. Its Protestant allies helped Pathfinder set up and manage rapid interventions such as the production of pamphlets, the smuggling of contraceptives, and the enrollment of physicians as advocates of the use of intrauterine devices. Although these rapid interventions helped quickly disseminate information and certain technologies among a fortunate few, they also weakened legitimate state agencies, neglected the monitoring of the safety of the drugs supplied, and alienated allies with their high-handed boldness. PMID:24976165

López, L Necochea

2014-01-01

353

The MARS pathfinder end-to-end information system: A pathfinder for the development of future NASA planetary missions  

NASA Technical Reports Server (NTRS)

The development of the Mars pathfinder is considered with emphasis on the End-to-End Information System (EEIS) development approach. The primary mission objective is to successfully develop and deliver a single flight system to the Martian surface, demonstrating entry, descent and landing. The EEIS is a set of functions distributed throughout the flight, ground and Mission Operation Systems (MOS) that inter-operate in order to control, collect, transport, process, store and analyze the uplink and downlink information flows of the mission. Coherence between the mission systems is achieved though the EEIS architecture. The key characteristics of the system are: a concurrent engineering approach for the development of flight, ground and mission operation systems; the fundamental EEIS architectural heuristics; a phased incremental EEIS development and test approach, and an EEIS design deploying flight, ground and MOS operability features, including integrated ground and flight based toolsets.

Cook, Richard A.; Kazz, Greg J.; Tai, Wallace S.

1996-01-01

354

Pathfinder aircraft prepared for flight showing solar cell arrays on wing  

NASA Technical Reports Server (NTRS)

The solar cell arrays, which cover about 75 percent of its upper wing surface, are clearly evident in this view of the Pathfinder solar-electric aircraft. The solar arrays are capable not only of absorbing direct sunlight, but can also absorb light reflected from the ground through the transparent lower surface of the 98-foot-long wing. Engineers and technicians from Pathfinder's developer, AeroVironment, Inc., conducted a successful two-hour check-out flight from NASA's Dryden Flight Research Center, Edwards, California, on Nov. 19, 1996. The craft then underwent preperations at AeroVironment's Simi Valley, California, facility for a new series of flight tests in Hawaii, during summer, 1997. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

355

A stamp commemorating NASA's Mars Pathfinder mission is unveiled at KSC's Visitor Complex  

NASA Technical Reports Server (NTRS)

Nancy Warren, supervisor of stamp distribution for the U.S. Post Office, unveils the $3 commemorative Mars Pathfinder postage stamp at Kennedy Space Center's Visitor Complex on the second day of its issue. The stamp was first issued on Dec. 10 at the Jet Propulsion Laboratory, Pasadena, Calif. It depicts the Sojourner rover at rest on the Pathfinder spacecraft with a panoramic Martian view that is based on one of the first mission images sent back to Earth.

1997-01-01

356

Coral Skeletons Provide Historical Evidence of Phosphorus Runoff on the Great Barrier Reef  

PubMed Central

Recently, the inshore reefs of the Great Barrier Reef have declined rapidly because of deteriorating water quality. Increased catchment runoff is one potential culprit. The impacts of land-use on coral growth and reef health however are largely circumstantial due to limited long-term data on water quality and reef health. Here we use a 60 year coral core record to show that phosphorus contained in the skeletons (P/Ca) of long-lived, near-shore Porites corals on the Great Barrier Reef correlates with annual records of fertiliser application and particulate phosphorus loads in the adjacent catchment. Skeletal P/Ca also correlates with Ba/Ca, a proxy for fluvial sediment loading, again linking near-shore phosphorus records with river runoff. Coral core records suggest that phosphorus levels increased 8 fold between 1949 and 2008 with the greatest levels coinciding with periods of high fertiliser-phosphorus use. Periods of high P/Ca correspond with intense agricultural activity and increased fertiliser application in the river catchment following agricultural expansion and replanting after cyclone damage. Our results demonstrate how coral P/Ca records can be used to assess terrestrial nutrient loading of vulnerable near-shore reefs. PMID:24086606

Mallela, Jennie; Lewis, Stephen E.; Croke, Barry

2013-01-01

357

A deep reef in deep trouble  

USGS Publications Warehouse

The well-documented degradation of shallower reefs which are often closer to land and more vulnerable to pollution, sewage and other human-related stressors has led to the suggestion that deeper, more remote offshore reefs could possibly serve as sources of coral and fish larvae to replenish the shallower reefs. Yet, the distribution, status, and ecological roles of deep (>30 m) Caribbean reefs are not well known. In this report, an observation of a deep reef which has undergone a recent extensive loss of coral cover is presented. In stark contrast to the typical pattern of coral loss in shallow reefs, the deeper corals were most affected. This report is the first description of such a pattern of coral loss on a deep reef.

Menza, C.; Kendall, M.; Rogers, C.; Miller, J.

2007-01-01

358

NOAA Coral Reef Watch: Remote Sensing and Coral Reefs  

NSDL National Science Digital Library

Developed by a fifth grade teacher, the Remote Sensing and Coral Reefs curriculum includes lesson plans, which feature links to additional information, and PowerPoint presentations. Topics discussed include altimetry, phytoplankton and ocean color, symbiosis and coral anatomy, sea surface temperature and coral bleaching, and conservation. The lesson plans can be used in sequence or by themselves.

359

Accretion history of mid-Holocene coral reefs from the southeast Florida continental reef tract, USA  

NASA Astrophysics Data System (ADS)

Sixteen new coral reef cores were collected to better understand the accretion history and composition of submerged relict reefs offshore of continental southeast (SE) Florida. Coral radiometric ages from three sites on the shallow inner reef indicate accretion initiated by 8,050 Cal BP and terminated by 5,640 Cal BP. The reef accreted up to 3.75 m of vertical framework with accretion rates that averaged 2.53 m kyr-1. The reef was composed of a nearly even mixture of Acropora palmata and massive corals. In many cases, cores show an upward transition from massives to A. palmata and may indicate local dominance by this species prior to reef demise. Quantitative macroscopic analyses of reef clasts for various taphonomic and diagenetic features did not correlate well with depth/environmental-related trends established in other studies. The mixed coral framestone reef lacks a classical Caribbean reef zonation and is best described as an immature reef and/or a series of fused patch reefs; a pattern that is evident in both cores and reef morphology. This is in stark contrast to the older and deeper outer reef of the SE Florida continental reef tract. Accretion of the outer reef lasted from 10,695-8,000 Cal BP and resulted in a larger and better developed structure that achieved a distinct reef zonation. The discrepancies in overall reef morphology and size as well as the causes of reef terminations remain elusive without further study, yet they likely point to different climatic/environmental conditions during their respective accretion histories.

Stathakopoulos, A.; Riegl, B. M.

2015-03-01

360

Validation of the Version 1 NOAA/NASA Pathfinder Sea Surface Temperature Data Set  

NASA Technical Reports Server (NTRS)

A high-resolution, global satellite-derived sea surface temperature (SST) data set called Pathfinder, from the Advanced Very High Resolution Radiometer (AVHRR) aboard the NOAA Polar Orbiters, is available from the Jet Propulsion Laboratory Physical Oceanography Distributed Active Archive Center (JPL PO.DAAC). Suitable for research as well as education, the Pathfinder SST data set is a result of a collaboration between the National Oceanographic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA) and investigators at several universities. NOAA and NASA are the sponsors of the Pathfinder Program, which takes advantage of currently archived Earth science data from satellites. Where necessary, satellite sensors have been intercalibrated, algorithms improved and processing procedures revised, in order to produce long time-series, global measurements of ocean, land and atmospheric properties necessary for climate research. Many Pathfinder data sets are available to researchers now, nearly a decade before the first launch of NASA's Earth Observing System (EOS). The lessons learned from the Pathfinder programs will facilitate the processing and management of terabytes of data from EOS. The Oceans component of Pathfinder has undertaken to reprocess all Global Area Coverage (GAC) data acquired by the 5-channel AVHRRs since 1981. The resultant data products are consistent and stably calibrated [Rao, 1993a, Rao, 1993b, Brown et al., 1993], Earth-gridded SST fields at a variety of spatial and temporal resolutions.

Smith, Elizabeth A.

1998-01-01

361

Catchment to Reef: Water Quality Issues in the  

E-print Network

Centre is a knowledge-based partnership of coral reef managers, researchers and industry. Partner research solutions to protect, conserve and restore the world's coral reef ecosystems. CRC Reef ResearchCatchment to Reef: Water Quality Issues in the Great Barrier Reef Region. 9-11 March 2004

Marsh, Helene

362

DYNAMIC CHANGES IN COLORED DISSOLVED ORGANIC MATTER AND TOTAL SUSPENDED MATTER CONTROL UV EXPOSURE OF CORAL REEFS IN THE FLORIDA KEYS  

EPA Science Inventory

Variation in ultraviolet (UV) light exposure is one important environmental factor that influences the health of coral reefs. Here we present evidence that the reef tract in the Florida Keys experiences significantly higher variability in UV exposure than other surrounding coast...

363

A multi-scale biophysical model to inform regional management of coral reefs in the western Philippines and South China Sea  

Microsoft Academic Search

The health and functioning of coral reef ecosystems worldwide is in decline, and in the face of increasing anthropogenic stress, the rate of decline of these important ecosystems is set to accelerate. Mitigation strategies at regional scales are costly, but nevertheless critical, as reef systems are highly connected across regions by ocean transport of both larval propagules and pollutants. It

J. Melbourne-Thomas; C. R. Johnson; P. M. Aliño; R. C. Geronimo; C. L. Villanoy; G. G. Gurney

2011-01-01

364

Conservation, precaution, and Caribbean reefs  

Microsoft Academic Search

Some authors argue that overfishing is an important reason that reef corals have declined in recent decades. Their reasoning is that overfishing removes herbivores, releasing macroalgae to overgrow and kill the corals. The evidence suggests, however, that global climate change and emergent marine diseases make a far greater contribution to coral mortality, and that macroalgae generally grow on the exposed

Richard B. Aronson; William F. Precht

2006-01-01

365

Reef tanks, public aquariums and  

E-print Network

of sponges, soft corals, coral rock and other algae, these green algae cover hard substrates and corals, such as the glass-anemone (Aiptasia pallida), the fireworm (Hermodice carunculata) and the bubble algae (Valonia spp (Decapoda: Brachyura: Majidae) are utilized in reef aquaria to control nuisance algae, particularly bubble

Watson, Andrew

366

Quantifying Coral Reef Ecosystem Services  

EPA Science Inventory

Coral reefs have been declining during the last four decades as a result of both local and global anthropogenic stresses. Numerous research efforts to elucidate the nature, causes, magnitude, and potential remedies for the decline have led to the widely held belief that the recov...

367

Sublittoral Reef Phenomena of Aldabra  

Microsoft Academic Search

DURING phase 6 of the Royal Society expedition to Aldabra the sublittoral structure of the reef front was studied by means of one detailed reference transect (marked 1 in Fig. 1) and thirteen survey transects. All were levelled by SCUBA divers in the following way. Two divers holding the ends of a 10 m tape ``leapfrogged'' over each other in

J. Barnes; D. J. Bellamy; D. J. Jones; B. A. Whitton

1970-01-01

368

Sandstone Spire in Capitol Reef  

USGS Multimedia Gallery

A view of a sandstone spire in Capitol Reef National Park. This area, known as the Fruita, is made up of three primary layers. The bottom sandstone layer is known as the Moenkopi Formation and is about 245 million years old. The middle gray-green layer is known as the Chinle Formation and was laid d...

369

The future of coral reefs  

PubMed Central

Coral reefs, with their millions of species, have changed profoundly because of the effects of people, and will continue to do so for the foreseeable future. Reefs are subject to many of the same processes that affect other human-dominated ecosystems, but some special features merit emphasis: (i) Many dominant reef builders spawn eggs and sperm into the water column, where fertilization occurs. They are thus particularly vulnerable to Allee effects, including potential extinction associated with chronic reproductive failure. (ii) The corals likely to be most resistant to the effects of habitat degradation are small, short-lived “weedy” corals that have limited dispersal capabilities at the larval stage. Habitat degradation, together with habitat fragmentation, will therefore lead to the establishment of genetically isolated clusters of inbreeding corals. (iii) Increases in average sea temperatures by as little as 1°C, a likely result of global climate change, can cause coral “bleaching” (the breakdown of coral–algal symbiosis), changes in symbiont communities, and coral death. (iv) The activities of people near reefs increase both fishing pressure and nutrient inputs. In general, these processes favor more rapidly growing competitors, often fleshy seaweeds, and may also result in explosions of predator populations. (v) Combinations of stress appear to be associated with threshold responses and ecological surprises, including devastating pathogen outbreaks. (vi) The fossil record suggests that corals as a group are more likely to suffer extinctions than some of the groups that associate with them, whose habitat requirements may be less stringent. PMID:11344288

Knowlton, Nancy

2001-01-01

370

Coral Reefs (2005) 24: 593 DOI 10.1007/s00338-005-0043-zReef sites  

E-print Network

Coral Reefs (2005) 24: 593 DOI 10.1007/s00338-005-0043-zReef sites Fig. 2 Fossil coral reef in southern Exmouth Gulf, Western Australia. The fossil coral reef is exposed at Point Maxwell et al. (1998) and White et al. (1998). U-series dates obtained from reef corals preserved

Greenstein, Benjamin J.

371

Battelle developing reefs to ease habitat losses  

SciTech Connect

Artificial reefs may be the answer to solving a worldwide problem of declining fish habitats, or they may only be good for creating fishing spots. Researchers at Battelle's Ocean Sciences Laboratory in Duxbury, Massachusetts, are studying artificial reefs in the Delaware River to determine if they are a solution to habitat losses in estuaries and coastal regions. [open quotes]Right now, we don't know if the fish are using the reefs simply as a grazing land, and then moving on, or if they're using the areas to colonize,[close quotes] said researcher Karen Foster. [open quotes]Ultimately, we hope to find they are colonizing.[close quotes] In 1989, Battelle researchers placed 16 prefabricated concrete reefs 45 feet deep in Delaware Bay. The reefs were placed in clusters of four, and monitoring began the following year. The federal government ordered the reefs placed in the bay as a mitigation technique for fish habitat that was lost when the river was dredged for navigational purposes. Researchers examined the reefs twice last summer. It will take five years, Foster said, before researchers can determine if the reefs are increasing the fish population. Early tests show, however, the populations of mussels, sponges, corals, and anemones increased by up to 150 percent over an area of bay bottom where the reefs were placed. Divers take crustacean samples from the reefs, and fish are caught near the reefs for examination. Researchers dissect the fish stomachs and analyze the contents to determine if they have been feeding at the reefs. [open quotes]If we find blue mussels in the stomach of the fish, that's great because we know that blue mussels are growing on the reef,[close quotes] Foster said.

Not Available

1993-04-01

372

78 FR 67128 - Coral Reef Conservation Program; Meeting  

Federal Register 2010, 2011, 2012, 2013, 2014

...National Oceanic and Atmospheric Administration Coral Reef Conservation Program; Meeting AGENCY: Coral Reef Conservation Program, Office of Ocean...hereby given of a public meeting of the U.S. Coral Reef Task Force (USCRTF). The meeting...

2013-11-08

373

The Earth System Science Pathfinder Orbiting Carbon Observatory (OCO) Mission  

NASA Technical Reports Server (NTRS)

A viewgraph presentation describing the Earth System Science Pathfinder Orbiting Carbon Observatory (OCO) Mission is shown. The contents include: 1) Why CO2?; 2) What Processes Control CO2 Sinks?; 3) OCO Science Team; 4) Space-Based Measurements of CO2; 5) Driving Requirement: Precise, Bias-Free Global Measurements; 6) Making Precise CO2 Measurements from Space; 7) OCO Spatial Sampling Strategy; 8) OCO Observing Modes; 9) Implementation Approach; 10) The OCO Instrument; 11) The OCO Spacecraft; 12) OCO Will Fly in the A-Train; 13) Validation Program Ensures Accuracy and Minimizes Spatially Coherent Biases; 14) Can OCO Provide the Required Precision?; 15) O2 Column Retrievals with Ground-based FTS; 16) X(sub CO2) Retrieval Simulations; 17) Impact of Albedo and Aerosol Uncertainty on X(sub CO2) Retrievals; 18) Carbon Cycle Modeling Studies: Seasonal Cycle; 19) Carbon Cycle Modeling Studies: The North-South Gradient in CO2; 20) Carbon Cycle Modeling Studies: Effect of Diurnal Biases; 21) Project Status and Schedule; and 22) Summary.

Crisp, David

2003-01-01

374

Model Checking Real Time Java Using Java PathFinder  

NASA Technical Reports Server (NTRS)

The Real Time Specification for Java (RTSJ) is an augmentation of Java for real time applications of various degrees of hardness. The central features of RTSJ are real time threads; user defined schedulers; asynchronous events, handlers, and control transfers; a priority inheritance based default scheduler; non-heap memory areas such as immortal and scoped, and non-heap real time threads whose execution is not impeded by garbage collection. The Robust Software Systems group at NASA Ames Research Center has JAVA PATHFINDER (JPF) under development, a Java model checker. JPF at its core is a state exploring JVM which can examine alternative paths in a Java program (e.g., via backtracking) by trying all nondeterministic choices, including thread scheduling order. This paper describes our implementation of an RTSJ profile (subset) in JPF, including requirements, design decisions, and current implementation status. Two examples are analyzed: jobs on a multiprogramming operating system, and a complex resource contention example involving autonomous vehicles crossing an intersection. The utility of JPF in finding logic and timing errors is illustrated, and the remaining challenges in supporting all of RTSJ are assessed.

Lindstrom, Gary; Mehlitz, Peter C.; Visser, Willem

2005-01-01

375

Multiple Sun-Earth Saddle Point flybys for LISA Pathfinder  

NASA Astrophysics Data System (ADS)

LISA Pathfinder is an ESA mission due to be launched in the next two years. The gravity gradiometer onboard has the sensitivity required to test predictions by gravitational theories proposed as alternatives to Dark Matter such as TeVeS. Within the Solar System measurable effects are predicted only in the vicinity of gravitational saddle points (SP). For this reason it has been proposed to fly LPF by the Earth-Sun SP, at some 259,000 km from Earth. This could be done in an extension to the nominal mission which uses a Lissajous orbit about the Earth-Sun L1 point. The responsibility for LPF mission design lies with ESA/ESOC, who have designed the transfer trajectories, orbits about L1, and station keeping strategies. This article describes an analysis performed by Astrium to support a suggestion for a possible mission extension to a saddle point crossing. With only very limited fuel availability, reaching the saddle point is a significant challenge. In this article, we present recent advances in the work on trajectory design. It is demonstrated that reaching the SP is feasible once the LPF mission is completed. Furthermore, in a significant enhancement, it is demonstrated that trajectories including more than one SP flyby are possible, thus improving the science return for this proposed mission extension.

Fabacher, Emilien; Kemble, Stephen; Trenkel, Christian; Dunbar, Neil

2013-07-01

376

Antenna Deployment for a Pathfinder Lunar Radio Observatory  

NASA Technical Reports Server (NTRS)

A first step in the development of a large radio observatory on the moon for cosmological or other astrophysical and planetary goals is to deploy a few antennas as a pathfinder mission. In this presentation, we describe a mechanism being developed to deploy such antennas from a small craft, such as a Google Lunar X-prize lander. The antenna concept is to deposit antennas and leads on a polyimide film, such as Kapton, and to unroll the film on the lunar surface. The deployment technique utilized is to launch an anchor which pulls a double line from a reel at the spacecraft. Subsequently, the anchor is set by catching on the surface or collecting sufficient regolith. A motor then pulls in one end of the line, pulling the film off of its roller onto the lunar surface. Detection of a low frequency cutoff of the galactic radio background or of solar radio bursts by such a system would determine the maximum lunar ionospheric density at the time of measurement. The current design and testing, including videos of the deployment, will be presented. These activities are funded in part by the NASA Lunar Science Institute as an activity of the Lunar University Network for Astrophysical Research (LUNAR) consortium. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

MacDowall, Robert J.; Minetto, F. A.; Lazio, T. W.; Jones, D. L.; Kasper, J. C.; Burns, J. O.; Stewart, K. P.; Weiler, K. W.

2012-01-01

377

Science With The Australian Square Kilometre Array Pathfinder  

E-print Network

The future of cm and m-wave astronomy lies with the Square Kilometre Array (SKA), a telescope under development by a consortium of 17 countries that will be 50 times more sensitive than any existing radio facility. Most of the key science for the SKA will be addressed through large-area imaging of the Universe at frequencies from a few hundred MHz to a few GHz. The Australian SKA Pathfinder (ASKAP) is a technology demonstrator aimed in the mid-frequency range, and achieves instantaneous wide-area imaging through the development and deployment of phased-array feed systems on parabolic reflectors. The large field-of-view makes ASKAP an unprecedented synoptic telescope that will make substantial advances in SKA key science. ASKAP will be located at the Murchison Radio Observatory in inland Western Australia, one of the most radio-quiet locations on the Earth and one of two sites selected by the international community as a potential location for the SKA. In this paper, we outline an ambitious science program for ASKAP, examining key science such as understanding the evolution, formation and population of galaxies including our own, understanding the magnetic Universe, revealing the transient radio sky and searching for gravitational waves.

Simon Johnston

2007-11-14

378

PathFinder Science: Keeping an Eye on Ozone  

NSDL National Science Digital Library

This site offers information and research projects that engage students in learning about ground level ozone. As part of the Pathfinder Science Collaborative Research program, students conduct scientific research on real-world topics to understand the process of science. They then submit their data so that other students and scientists around the world gain a better understanding of the issues and drive further research. Other topics include monitoring monarch butterflies, lichens, and greenhouse gases. In this forum, students determine the level of tropospheric ozone in their area and the impact on organisms in the environment, such as the milkweed plant. Background information, instructions for making ozone testing paper, and a protocol for measuring the impact of ozone on milkweed plant are provided. After collecting data, students submit it electronically and then access other students' data to develop and answer further research questions. The site also offers information on formulating questions, research methods, and data analysis along with the process and values that underlie scientific research.

379

Slope Morphology of Twin Peaks, Mars Pathfinder Landing Site  

NASA Astrophysics Data System (ADS)

Development of slope form over time has long been a concern of geomorphologists, although recently this concern has been moved to slope processes rather than form. There are two basic approaches. The first is theoretical, involving modeling of different types and rates of processes, and calculation of results in terms of slope evolution over time. Comparisons with real-life slopes can follow this approach [1], [2]. The second, inductive, approach involves field measurements to test ideas about slope evolution starting from the assumption that observed slopes represent different stages of an essentially similar evolution [3]. Space is substituted for time, and a number of slopes, assumed to be of increasing age, are measured and placed in an evolutionary sequence (e.g. [4], [5], [6]). [5] showed that slope angles are modally distributed, with the modal angles controlled by the materials (regolith) of which the slopes are formed, and by the processes operating on them. Data can be obtained directly from field work or from digital elevation models (DEM) derived from remote sensing investigations [7]. DEMs are particularly useful to study inaccessible planets, such as Mars, where on site observations are restricted to only a few landing sites. Here we present a study of slopes on the Twin Peaks, two small hills located 780 m north and 910 m south of the Mars Pathfinder landing site at the mouth of the Ares and Tiu flood channels. The presence of streamlined hills, jumbled surfaces and conglomerates suggested the region was modified by massive flooding 1.8 - 3.5 billion years ago [8], [9]. The streamlined forms and terraces of the Twin Peaks were taken to indicate catastrophic flood conditions that were believed to be prevalent in the area [8]. It was also suggested that the northernmost peak was topped by floodwater, causing its flatter appearance. Other researchers postulated alternative geomorphological origins for the features observed at the Pathfinder landing site. Processes such as ice flow or deposition were proposed as being the principal cause of most of observed features, by analogy with similar features observed on Earth [10]. Here we propose that the slopes on the Twin Peaks may provide an indication of the processes that shaped them after they were formed. This work shows the results of a detailed morphometric analysis of slopes on the southernmost peak, conducted to gain a greater understanding of past and present slope processes at work at the Pathfinder landing site. The southern Twin Peak is a conical hill rising 38 m above the local terrain. A portion of the Pathfinder super panorama was used to analyse the hill-slope morphology. The camera horizon was used as a baseline and all slope angles were measured from this. The hill comprises four separate regions including the top of the hill, which is convex in shape. The convex nature of the hilltop is a common if not ubiquitous feature of hills regardless of their origin. It is related to the creep processes that frequently dominate the tops of hill slopes. In this case it was probably caused by heating and cooling during the Martian diurnal cycle, by the action of soil water, or a combination of both. All slope sections were observed to be similar in length. The slopes nearest the hill top measure 21? and 22.5? respectively on the north and south sides of the Southern Twin Peak. Mid way down the hill the next sequence of slopes have north and south angles of 9? and 15? respectively. Shallow end-slopes measure 4? and 5? north and south respectively. Similarity of slope angles and lengths indicates symmetry, suggesting that the rocks are the same all around the hill. Our analysis suggests that slope angles are controlled by a combination of the materials of which they are formed and the processes that are operating on them. Their primarily symmetrical outlook indicates no structural control, suggesting that the hill is formed by flat-lying or massive homogeneous rocks. This being the case, slope morphology results from shallow processes related to mass was

Hobbs, Steven; Paine, Colin; Clarke, Jon; Caprarelli, Graziella

2010-05-01

380

Polar Geophysics Products Derived from AVHRR: The "AVHRR Polar Pathfinder  

NASA Technical Reports Server (NTRS)

This NOAA/NASA Pathfinder effort was established to locate, acquire, and process Advanced Very High Resolution Radiometer (AVHRR) imagery into geo-located and calibrated radiances, cloud masks, surface clear-sky broadband albedo, clear-sky skin temperatures, satellite viewing times, and viewing and solar geometry for the, high-latitude portions of the northern and southern hemispheres (all area north of 48N and south of 53S). AVHRR GAC data for August 1981 - July 1998 were acquired, with some gaps remaining, and processed into twice-daily 5-km grids, with some products also provided at 25-km resolution. AVHRR LAC data for 3.5 years of coverage in the northern hemisphere and 2.75 years of coverage in the southern hemisphere were processed into 1.25-km grids for the same suite of products. The resulting data sets are presently being transferred to the National Snow and Ice Data Center (NSIDC) for archiving and distribution. Using these data, researchers now have at their disposal an extensive AVHRR data set for investigations of high-latitude processes. In addition, the data lend themselves to development and testing of algorithms. The products are particularly relevant for climate research and algorithm development as applied to relatively long time periods and large areas.

Maslanik, James; Fowler, Charles; Scambos, Theodore

1999-01-01

381

Reef-Building Corals of Vietnam as a Part of the Indo-Pacific Reef Ecosystem  

Microsoft Academic Search

The paper analyzes both published and unpublished results of the investigations of Vietnamese reef-building corals and reefs\\u000a performed in the last decades of the twentieth century. The state of the art in the study of reef-building scleractinian corals\\u000a and reefs is presented. The scleractinian fauna of Vietnam is shown to match in species diversity (366 species of 70 genera)\\u000a the

Yu. Ya. Latypov

2005-01-01

382

Trade off analysis for participatory coral reef management: lessons learned from Buccoo Reef Marine Park, Tobago  

Microsoft Academic Search

Coral reefs provide a range of important functions and services, yet often conflicts exist over coral reef use among multiple users. This paper outlines the trade-off analysis approach to coral reef management where multiple and conflicting objectives for coral reef resources can be identified, assessed and reconciled within a decision-support framework. The paper applies trade-off analysis to the case of

E. Tompkins; K. Brown; W. N. Adger; P. Bacon; K. Young; D. Shim

383

Delineating optimal settlement areas of juvenile reef fish in Ngederrak Reef, Koror state, Republic of Palau.  

PubMed

Establishing the effectiveness of habitat features to act as surrogate measures of diversity and abundance of juvenile reef fish provides information that is critical to coral reef management. When accurately set on a broader spatial context, microhabitat information becomes more meaningful and its management application becomes more explicit. The goal of the study is to identify coral reef areas potentially important to juvenile fishes in Ngederrak Reef, Republic of Palau, across different spatial scales. To achieve this, the study requires the accomplishment of the following tasks: (1) structurally differentiate the general microhabitat types using acoustics; (2) quantify microhabitat association with juvenile reef fish community structure; and (3) conduct spatial analysis of the reef-wide data and locate areas optimal for juvenile reef fish settlement. The results strongly suggest the importance of branching structures in determining species count and abundance of juvenile reef fish at the outer reef slope of Ngederrak Reef. In the acoustic map, the accurate delineation of these features allowed us to identify reef areas with the highest potential to harbor a rich aggregation of juvenile reef fish. Using a developed spatial analysis tool that ranks pixel groups based on user-defined parameters, the reef area near the Western channel of Ngederrak is predicted to have the most robust aggregation of juvenile reef fish. The results have important implications not only in management, but also in modeling the impacts of habitat loss on reef fish community. At least for Ngederrak Reef, the results advanced the utility of acoustic systems in predicting spatial distribution of juvenile fish. PMID:25394769

Ticzon, Victor S; Foster, Greg; David, Laura T; Mumby, Peter J; Samaniego, Badi R; Madrid, Val Randolf

2015-01-01

384

Diving down the reefs? Intensive diving tourism threatens the reefs of the northern Red Sea  

Microsoft Academic Search

Intensive recreational SCUBA diving threatens coral reef ecosystems. The reefs at Dahab, South Sinai, Egypt, are among the world’s most dived (>30,000divesy?1). We compared frequently dived sites to sites with no or little diving. Benthic communities and condition of corals were examined by the point intercept sampling method in the reef crest zone (3m) and reef slope zone (12m). Additionally,

Harald Hasler; Jörg A. Ott

2008-01-01

385

Sedimentation on three caribbean atolls: Glovers reef, lighthouse reef and turneffe Islands, belize  

Microsoft Academic Search

Summary  The chief mode of carbonate sedimentation on the Belizean atolls Glovers Reef, Lighthouse Reef and Turneffe Islands is the\\u000a accumulation of organically-derived particles. Variations in the distribution of the composition and grain-sizes of surface\\u000a sediments, collected along transects across the atolls, are environmentally controlled. Two major sediment types may be distinguished.\\u000a (1) Reef and fore reef sediments are dominated by

Eberhard Gischler

1994-01-01

386

Live coral cover in the fossil record: an example from Holocene reefs of the Dominican Republic  

NASA Astrophysics Data System (ADS)

Fossil reefs hold important ecological information that can provide a prehuman baseline for understanding recent anthropogenic changes in reefs systems. The most widely used proxy for reef "health," however, is live coral cover, and this has not been quantified in the fossil record because it is difficult to establish that even adjacent corals were alive at the same time. This study uses microboring and taphonomic proxies to differentiate between live and dead corals along well-defined time surfaces in Holocene reefs of the Enriquillo Valley, Dominican Republic. At Cañada Honda, live coral cover ranged from 59 to 80% along a contemporaneous surface buried by a storm layer, and the reef, as a whole had 33-80% live cover within the branching, mixed, massive and platy zones. These values equal or exceed those in the Dominican Republic and Caribbean today or reported decades ago. The values from the western Dominican Republic provide a geologic baseline against which modern anthropogenic changes in Caribbean reefs can be considered.

Lescinsky, H.; Titus, B.; Hubbard, D.

2012-06-01

387

Evaluating coral reef health in American Samoa  

USGS Publications Warehouse

The study of coral disease has suffered from an absence of systematic approaches that are commonly used to determine causes of diseases in animals. There is a critical need to develop a standardized and portable nomenclature for coral lesions in the field and to incorporate more commonly available biomedical tools in coral disease surveys to determine the potential causes of lesions in corals. We characterized lesions in corals from American Samoa based on gross and microscopic morphology and classified them as discoloration, growth anomalies, or tissue loss. The most common microscopic finding in corals manifesting discoloration was the depletion of zooxanthellae, followed by necrosis, sometimes associated with invasive algae or fungi. The most common microscopic lesion in corals manifesting tissue loss was cell necrosis often associated with algae, fungi, or protozoa. Corals with growth anomaly had microscopic evidence of hyperplasia of gastrovascular canals, followed by necrosis associated with algae or metazoa (polychaete worms). Several species of apparently normal corals also had microscopic changes, including the presence of bacterial aggregates or crustacea in tissues. A single type of gross lesion (e.g., discoloration) could have different microscopic manifestations. This phenomenon underlines the importance of using microscopy to provide a more systematic description of coral lesions and to detect potential pathogens associated with these lesions.

Work, T.M.; Rameyer, R.A.

2005-01-01

388

ReefLink Database: A decision support tool for Linking Coral Reefs and Society Through Systems Thinking  

EPA Science Inventory

Coral reefs provide the ecological foundation for productive and diverse fish and invertebrate communities that support multibillion dollar reef fishing and tourism industries. Yet reefs are threatened by growing coastal development, climate change, and over-exploitation. A key i...

389

Assessing Coral Reefs on a Pacific-Wide Scale Using the Microbialization Score  

PubMed Central

The majority of the world's coral reefs are in various stages of decline. While a suite of disturbances (overfishing, eutrophication, and global climate change) have been identified, the mechanism(s) of reef system decline remain elusive. Increased microbial and viral loading with higher percentages of opportunistic and specific microbial pathogens have been identified as potentially unifying features of coral reefs in decline. Due to their relative size and high per cell activity, a small change in microbial biomass may signal a large reallocation of available energy in an ecosystem; that is the microbialization of the coral reef. Our hypothesis was that human activities alter the energy budget of the reef system, specifically by altering the allocation of metabolic energy between microbes and macrobes. To determine if this is occurring on a regional scale, we calculated the basal metabolic rates for the fish and microbial communities at 99 sites on twenty-nine coral islands throughout the Pacific Ocean using previously established scaling relationships. From these metabolic rate predictions, we derived a new metric for assessing and comparing reef health called the microbialization score. The microbialization score represents the percentage of the combined fish and microbial predicted metabolic rate that is microbial. Our results demonstrate a strong positive correlation between reef microbialization scores and human impact. In contrast, microbialization scores did not significantly correlate with ocean net primary production, local chla concentrations, or the combined metabolic rate of the fish and microbial communities. These findings support the hypothesis that human activities are shifting energy to the microbes, at the expense of the macrobes. Regardless of oceanographic context, the microbialization score is a powerful metric for assessing the level of human impact a reef system is experiencing. PMID:22970122

McDole, Tracey; Nulton, James; Barott, Katie L.; Felts, Ben; Hand, Carol; Hatay, Mark; Lee, Hochul; Nadon, Marc O.; Nosrat, Bahador; Salamon, Peter; Bailey, Barbara; Sandin, Stuart A.; Vargas-Angel, Bernardo; Youle, Merry; Zgliczynski, Brian J.; Brainard, Russell E.; Rohwer, Forest

2012-01-01

390

Assessing coral reefs on a Pacific-wide scale using the microbialization score.  

PubMed

The majority of the world's coral reefs are in various stages of decline. While a suite of disturbances (overfishing, eutrophication, and global climate change) have been identified, the mechanism(s) of reef system decline remain elusive. Increased microbial and viral loading with higher percentages of opportunistic and specific microbial pathogens have been identified as potentially unifying features of coral reefs in decline. Due to their relative size and high per cell activity, a small change in microbial biomass may signal a large reallocation of available energy in an ecosystem; that is the microbialization of the coral reef. Our hypothesis was that human activities alter the energy budget of the reef system, specifically by altering the allocation of metabolic energy between microbes and macrobes. To determine if this is occurring on a regional scale, we calculated the basal metabolic rates for the fish and microbial communities at 99 sites on twenty-nine coral islands throughout the Pacific Ocean using previously established scaling relationships. From these metabolic rate predictions, we derived a new metric for assessing and comparing reef health called the microbialization score. The microbialization score represents the percentage of the combined fish and microbial predicted metabolic rate that is microbial. Our results demonstrate a strong positive correlation between reef microbialization scores and human impact. In contrast, microbialization scores did not significantly correlate with ocean net primary production, local chla concentrations, or the combined metabolic rate of the fish and microbial communities. These findings support the hypothesis that human activities are shifting energy to the microbes, at the expense of the macrobes. Regardless of oceanographic context, the microbialization score is a powerful metric for assessing the level of human impact a reef system is experiencing. PMID:22970122

McDole, Tracey; Nulton, James; Barott, Katie L; Felts, Ben; Hand, Carol; Hatay, Mark; Lee, Hochul; Nadon, Marc O; Nosrat, Bahador; Salamon, Peter; Bailey, Barbara; Sandin, Stuart A; Vargas-Angel, Bernardo; Youle, Merry; Zgliczynski, Brian J; Brainard, Russell E; Rohwer, Forest

2012-01-01

391

Astronaut Photography of Coral Reefs  

NASA Technical Reports Server (NTRS)

Astronaut photographs of tropical coastal areas may contain information on submerged features, including coral reefs, up to depths of about 15 m in clear waters. Previous research efforts have shown that astronaut photographs can aid in estimating coral reef locations and extent on national, regional and global scales, and allow characterization of major geomorphological rim and lagoon features (Andrefouet et al. 2000, in preparation). They can be combined with traditional satellite data to help distinguish between clouds and lagoon features such as pinnacles (Andrefouet and Robinson, in review). Furthermore, astronaut photographs may provide reef scientists and managers with information on the location and extent of river plumes and sediment run off, or facilitate identification of land cover types, including mangroves (Webb et al., in press). Photographs included in the section were selected based on several criteria. The primary consideration of the editors was that the photographs represent a worldwide distribution of coral reefs, have extremely low visual interference by cloud cover, and display a spatial scale reasonable for examining reef-related features. Once photographs were selected, they were digitized from 2nd generation copies. The color and contrast were hand corrected to an approximation of natural color (required to account for spectral differences between photographs due to the color sensitivities of films used, and differences in sun angle and exposure of the photographs). None of the photographs shown here have been georeferenced to correct them to a map projection and scale. Any distortions in features due to slightly oblique look angles when the photographs were taken through spacecraft windows remain. When feasible, near vertical photographs have been rotated so that north is toward the top. An approximate scale bar and north arrow have added using distinctive features on each photograph with reference to a 1:1,000,000 scale navigation chart. Astronaut photographs provide a unique source of moderate resolution reef remote sensing data because of their global coverage and (immediate) availability in the public domain. The database of photographs can be searched an browsed online and high-resolution digital copies of photographs in this atlas can be accessed via the Website of Earth Science and Image Analysis at NASA's Johnson Space Center:

Robinson, Julie A.; Noordeloos, Marco

2001-01-01

392

Using Reef Check For Long-term Coral Reef Monitoring in Hawaii  

Microsoft Academic Search

A major goal of a government coral reef monitoring program is to provide the data required for management. But management programs will fail without community support. Involving the community in monitoring builds public support for management initiatives. The Reef Check coral reef survey program is carried out by volunteers from the community, particularly recreational divers. It was initially designed as

Gregor Hodgson; Carl M. Stepath

393

Rigs to reefs: a petroleum industry perspective  

E-print Network

of converting obsolete, nonproductive offshore oil and gas structures (primarily production platforms, but also drilling rigs) into artificial reefs. To date, five reefs have been constructed in this manner. In 1980, Exxon Company, U. S. A. donated a 2, 200... to reefs concept financially attractive and to resolve all lingering liability concerns, a viable program will not occur. It is important, then, to explore various alternatives to overcome these constraints. Specific 30 recommendations will be made...

Dubose, William Perry

1988-01-01

394

Pearl and Hermes Reef, Hawaiian Island Chain  

NASA Technical Reports Server (NTRS)

Pearl and Hermes Reef (28.0N, 176.0W) in the Hawaiian Island Chain, are seen with several small sandy islands, forming an atoll that caps a seamount on the long chain that extends some 1,500 miles northwestward from the more familiar Hawaiian Islands proper. Pearl and Hermes Reef lies about 100 miles southeast of Midway island. A reticulate network of coral patch reefs separates the lagoon into more or less isolated pools.

1992-01-01

395

United States Coral Reef Task Force  

NSDL National Science Digital Library

The U.S. Coral Reef Task Force was established to lead the U.S. response to the growing global environmental crisis facing our coral reefs. This site contains information on what coral reefs are, where they can be found, how to protect them, and what the threats are. Reports on Task Force accomplishments and documents about national action plans and other information on the Task Force and their meetings is also included.

396

Community ecology of mesophotic coral reef ecosystems  

Microsoft Academic Search

Given the global degradation of shallow-water coral reef ecosystems resulting from anthropogenic activities, mesophotic coral\\u000a reef ecosystems (MCEs) are gaining attention because they are generally considered a de facto refuge for shallow-water species.\\u000a Despite their inferred importance, MCEs remain one of the most understudied reef habitats, and basic information on the taxonomic\\u000a composition, depth range, habitat preferences, and abundance and

S. E. Kahng; J. R. Garcia-Sais; H. L. Spalding; E. Brokovich; D. Wagner; E. Weil; L. Hinderstein; R. J. Toonen

2010-01-01

397

Competition Among Sessile Organisms on Coral Reefs  

Microsoft Academic Search

\\u000a Competition among sessile organisms is a major process on coral reefs, and is becoming more important as anthropogenic disturbances\\u000a cause shifts in dominance to non-reef builders such as macroalgae, soft corals, ascidians, and corallimorpharians. Long-term\\u000a monitoring and field experiments have demonstrated that competition for limited space can exert major impacts on reef biodiversity\\u000a and community composition across habitats and regions.

Nanette E. Chadwick; Kathleen M. Morrow

398

Coral reef ecosystems and anthropogenic climate change  

Microsoft Academic Search

Coral reef ecosystems are among the most biologically diverse ecosystems on the planet. In addition to their value in terms\\u000a of biodiversity, coral reefs provide food and resources for over 500 million people. Despite their importance, coral reefs\\u000a are declining at a rapid rate (1–2% per year) as a result of a range of local (e.g., overexploitation of fisheries, declining\\u000a water

Ove Hoegh-Guldberg

2011-01-01

399

Climate change and coral reef connectivity  

Microsoft Academic Search

This review assesses and predicts the impacts that rapid climate change will have on population connectivity in coral reef\\u000a ecosystems, using fishes as a model group. Increased ocean temperatures are expected to accelerate larval development, potentially\\u000a leading to reduced pelagic durations and earlier reef-seeking behaviour. Depending on the spatial arrangement of reefs, the\\u000a expectation would be a reduction in dispersal

P. L. Munday; J. M. Leis; J. M. Lough; C. B. Paris; M. J. Kingsford; M. L. Berumen; J. Lambrechts

2009-01-01

400

Long-term monitoring of reef corals at the Flower Garden Banks (northwest Gulf of Mexico): Reef coral population changes and historical incorporation of barium in Montastrea annularis  

SciTech Connect

Reef coral populations were monitored from 1988 to 1991 at the Flower Garden Banks located in the northwestern Gulf of Mexico. The status of reef coral populations, and natural or man-made factors potentially affecting their well-being were determined. Man-made chronic disturbances are degrading coral reef resources on a global scale. Yet, the Flower Garden coral reefs seem to have been sheltered from the effects of regional stresses generated by population growth and increased industrial activity. Since 1974, reef coral population levels have remained unchanged in the Montastrea-Diploria Zones at the Flower Garden Banks. Live coral cover ranges between 46 and 46.5%. Montastrea annularis and Diploria strigosa comprise 80% of the coral cover on either bank. The remainder of the cover is mostly shared by eight other taxa. Coral taxa appear to be more homogeneously distributed on the West Bank. The relatively greater number of Agaricia spp., Madracis decastis, and P. astreoides colonies on the East Bank may be the source of a decreased evenness. The health of reef corals was assessed using repetitive and non-repetitive photographic methods, and accretionary growth measurements of M. annularis. Reef corals have undergone small scale changes at the Flower Gardens probably reflecting natural disturbance, predation, disease, and inter-specific competition. White mat disease (ridge disease) is shown to generate more tissue loss than any of the three bleaching events that took place at the Flower Gardens (1989, 1990, and 1991). Advance to retreat linear ratios of encrusting growth revealed a net tissue gain on the East Bank and a net tissue loss on the West Bank. Growth rates of M. annularis were highly variable. The annual barium content from 1910 in 1989 in a M. annularis colony from the West Flower Garden did not reveal trends associated with the extensive oil and gas exploration in the northern Gulf of Mexico.

Deslarzes, K.J.P.

1992-01-01

401

Pathfinder ground preparations prior to altitude record setting flight of 71,500 feet  

NASA Technical Reports Server (NTRS)

Technicians make final adjustments on the solar-powered Pathfinder remotely piloted research aircraft prior to the craft's taking off on a flight which established a new unofficial world's altitude record for both propellor-driven and solar-powered aircraft. The new record of more than 71,500 feet was set during a 14 1/2-hour flight July 7, 1997, from the U.S. Navy's Pacific Missile Range Facility (PMRF) at Barking Sands, Kauai, Hawaii. The new altitude record is subject to verification by the National Aeronautics Association. The Pathfinder took off at 8:34 a.m. HDT, passed its previous record altitude of 67,350 feet about 2:45 p.m., and then reached its new mark at about 4 p.m. Controllers on the ground then initiated a slow decent, and Pathfinder landed seven hours later at 11:05 p.m. HDT. The experimental Boeing Condor remotely-piloted aircraft had held the previous record for propellor-driven craft of 67,028 feet. The Pathfinder had exceeded that height on a previous flight on June 9, 1997, but not by a large enough margin to be considered a new record. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1997-01-01

402

Coral Reef Protection: A Watershed Approach  

NSDL National Science Digital Library

This colorful, straightforward site from the Environmental Protection Agency (EPA)'s Oceans and Coastal Protection division (described in the November 25, 1998 Scout Report for Science & Engineering) outlines coral reef basic ecology and protection. About Coral Reefs provides background ecological information on coral reefs; Initiatives and Activities highlights EPA's activities but includes other US initiatives and links to symposia preceedings, factsheets, and other resources; and Related Links provides additional information on coral reef protection from the international, non-governmental (as well as federal), and educational sectors. A selection of recent news items (on the front page) rounds out the site.

United States. Environmental Protection Agency. Office of Water.

1998-01-01

403

Onondage pinnacle reefs in New York State  

SciTech Connect

Onondaga pinnacle reefs, part of the Onondaga Formation, developed in an epeiric setting of the lowermost Middle Devonian (Eifelian). The reefs were initiated as coral-crinoidal mounds in the Edgecliff Member of the formation. Whereas most Devonian reefs are composed of rugose corals. Coral is the predominant kind of fossil, followed by crinoids, brachiopods, mollusks, undifferentiated skeletal debris, and possible sponges. The initial mineralogy of the corals is inferred to have been calcite. The porosity of these reefs is almost unique among reef reservoirs. most reefs produce from secondary or diagenetic porosity; by contrast Onondaga reefs display primary intracoralline or framework porosity. Between framework builders and/or skeletal particles cryptocrystalline/microcrystalline cement fills pores. As observed in modern reefs this kind of cement resembles micrite, but probable formed as high-magnesian calcite in a high-energy setting. Syntaxial or rim cement common lines crinoid particles. Some of these pinnacle reefs, formerly gas producers, are presently under development as gas-storage reservoirs.

Friedman, G.M. [Brooklyn College and Graduate School of CUNY, Brooklyn, NY (United States)

1995-09-01

404

Satellite Remote Sensing of Coral Reefs  

NSDL National Science Digital Library

Coral reefs are one of the most endangered ecosystems as coral reef coverage has declined dramatically in the past three decades. In recent years, satellite remote sensing has become a popular and effective mapping tool for ecological studies, especially in marine science. This lesson plan designed for high school science students demonstrates how marine scientists use satellite remote sensing to gather detailed information about coral reefs worldwide. An in-depth review of both remote sensing and coral reefs is also included in this article.

David Palandro

2005-09-01

405

Studies on the Great Barrier Reef  

SciTech Connect

Proposals to drill for oil on Australia's Great Barrier Reef have led to the appointment of a royal commission to study the environmental impact of such activities. The Australian Institute of Marine Science has developed a 5-part research plant which covers the Australian mangrove environment; nearshore habitat; processes and interactions, energy flows, resource cycling and their consequences within the reef ecosystems; patterns, abundances and relationships within the reef; and the continental shelf of the Great Barrier Reef region. Research in each of these areas is described.

Walton, S.

1985-01-01

406

Impacts of Artificial Reefs on Surrounding Ecosystems  

NASA Astrophysics Data System (ADS)

Artificial reefs are becoming a popular biological and management component in shallow water environments characterized by soft seabed, representing both important marine habitats and tools to manage coastal fisheries and resources. An artificial reef in the marine environment acts as an open system with exchange of material and energy, altering the physical and biological characteristics of the surrounding area. Reef stability will depend on the balance of scour, settlement, and burial resulting from ocean conditions over time. Because of the unstable nature of sediments, they require a detailed and systematic investigation. Acoustic systems like high-frequency multibeam sonar are efficient tools in monitoring the environmental evolution around artificial reefs, whereas water turbidity can limit visual dive and ROV inspections. A high-frequency multibeam echo sounder offers the potential of detecting fine-scale distribution of reef units, providing an unprecedented level of resolution, coverage, and spatial definition. How do artificial reefs change over time in relation to the coastal processes? How accurately does multibeam technology map different typologies of artificial modules of known size and shape? How do artificial reefs affect fish school behavior? What are the limitations of multibeam technology for investigating fish school distribution as well as spatial and temporal changes? This study addresses the above questions and presents results of a new approach for artificial reef seafloor mapping over time, based upon an integrated analysis of multibeam swath bathymetry data and geoscientific information (backscatter data analysis, SCUBA observations, physical oceanographic data, and previous findings on the geology and sedimentation processes, integrated with unpublished data) from Senigallia artificial reef, northwestern Adriatic Sea (Italy) and St. Petersburg Beach Reef, west-central Florida continental shelf. A new approach for observation of fish aggregations associated with Senigallia reef based on the analysis of multibeam backscatter data in the water column is also explored. The settlement of the reefs and any terrain change are investigated over time providing a useful description of the local hydrodynamics and geological processes. All the artificial structures (made up by water-based concrete for Senigallia reef and mainly steel for St. Petersburg Beach reef) are identified and those showing substantial horizontal and/or vertical movements are analyzed in detail. Most artificial modules of Senigallia reef are not intact and scour signatures are well depicted around them, indicating reversals of the local current. This is due to both the wind pattern and to the quite close arrangement of the reef units that tend to deflect the bottom flow. As regards to the St. Petersburg Beach reef, all the man-made steel units are still in their upright position. Only a large barge shows a gradual collapse of its south side, and presents well-developed scouring at its east-northeast side, indicating dominant bottom flow from west-southwest to east-northeast. While an overall seafloor depth shallowing of about 0.30 m from down-current deposits was observed for Senigallia reef, an overall deepening of about 0.08 m due to scour was observed at the St. Petersburg Beach reef. Based on the backscatter data interpretation, surficial sediments are coarser in the vicinities of both artificial reefs than corresponding surrounding sediments. Scouring reveals this coarser layer underneath the prevalent mud sediment at Senigallia reef, and the predominant silt sediment at St. Petersburg Beach reef. In the ten years of Senigalia reef study, large-scale variations between clay and silt appear to be directly linked to large flood events that have occurred just prior to the change. As regards the water column investigation, acoustic backscatter from fish aggregations gives detailed information on their morphology and spatial distribution. In addition, relative fish biomass estimates can be extrapolated. Results suggest that most of

Manoukian, Sarine

407

Conservation, precaution, and Caribbean reefs  

NASA Astrophysics Data System (ADS)

Some authors argue that overfishing is an important reason that reef corals have declined in recent decades. Their reasoning is that overfishing removes herbivores, releasing macroalgae to overgrow and kill the corals. The evidence suggests, however, that global climate change and emergent marine diseases make a far greater contribution to coral mortality, and that macroalgae generally grow on the exposed skeletal surfaces of corals that are already dead. Macroalgal dominance, therefore, is an effect rather than a cause of coral mortality. Marine protected areas (MPAs), which are usually established to protect stocks of reef fish, foster populations of herbivorous fish under at least some circumstances. Increased herbivory can reduce algal cover, potentially accelerating the recovery of coral populations inside MPAs; however, establishing MPAs will have only a limited impact on coral recovery unless policymakers confront the accelerating negative effects of the global-scale sources of coral mortality.

Aronson, Richard B.; Precht, William F.

2006-08-01

408

Nocturnal relocation of adult and juvenile coral reef fishes in response to reef noise  

NASA Astrophysics Data System (ADS)

Juvenile and adult reef fishes often undergo migration, ontogenic habitat shifts, and nocturnal foraging movements. The orientation cues used for these behaviours are largely unknown. In this study, the use of sound as an orientation cue guiding the nocturnal movements of adult and juvenile reef fishes at Lizard Island, Great Barrier Reef was examined. The first experiment compared the movements of fishes to small patch reefs where reef noise was broadcast, with those to silent reefs. No significant responses were found in the 79 adults that were collected, but the 166 juveniles collected showed an increased diversity each morning on the reefs with broadcast noise, and significantly greater numbers of juveniles from three taxa (Apogonidae, Gobiidae and Pinguipedidae) were collected from reefs with broadcast noise. The second experiment compared the movement of adult and juvenile fishes to reefs broadcasting high (>570 Hz), or low (<570 Hz) frequency reef noise, or to silent reefs. Of the 122 adults collected, the highest diversity was seen at the low frequency reefs; and adults from two families (Gobiidae and Blenniidae) preferred these reefs. A similar trend was observed in the 372 juveniles collected, with higher diversity at the reefs with low frequency noises. This preference was seen in the juvenile apogonids; however, juvenile gobiids were attracted to both high and low sound treatments equally, and juvenile stage Acanthuridae preferred the high frequency noises. This evidence that juvenile and adult reef fishes orientate with respect to the soundscape raises important issues for management, conservation and the protection of sound cues used in natural behaviour.

Simpson, S. D.; Jeffs, A.; Montgomery, J. C.; McCauley, R. D.; Meekan, M. G.

2008-03-01

409

A novel reef coral symbiosis  

Microsoft Academic Search

Reef building corals form close associations with unicellular microalgae, fungi, bacteria and archaea, some of which are symbiotic\\u000a and which together form the coral holobiont. Associations with multicellular eukaryotes such as polychaete worms, bivalves\\u000a and sponges are not generally considered to be symbiotic as the host responds to their presence by forming physical barriers\\u000a with an active growth edge in

O. Pantos; J. C. Bythell

2010-01-01

410

From ridge to reef—linking erosion and changing watersheds to impacts on the coral reef ecosystems of Hawai‘i and the Pacific Ocean  

USGS Publications Warehouse

Coral reef ecosystems are threatened by unprecedented watershed changes in the United States and worldwide. These ecosystems sustain fishing and tourism industries essential to the economic survival of many communities. Sediment, nutrients, and pollutants from watersheds are increasingly transported to coastal waters, where these contaminants damage corals. Although pollution from watersheds is one of many factors threatening coral survival, it is one that local people can have a profound influence on. U.S. Geological Survey scientists are using mapping, monitoring, and computer modeling to better forecast the effects of watershed changes on reef health. Working with communities in Hawai‘i and on other U.S. islands in the Pacific, they are helping to provide the science needed to make informed decisions on watershed and coral reef management.

Stock, Jonathan D.; Cochran, Susan A.; Field, Michael E.; Jacobi, James D.; Tribble, Gordon

2011-01-01

411

General geology and geomorphology of the Mars Pathfinder landing site  

USGS Publications Warehouse

The Mars Pathfinder (MPF) spacecraft landed on relatively young (late Hesperian-early Amazonian; 3.1-0.7 Ga) plains in Chryse Planitia near the mouth of Ares Vallis. Images returned from the spacecraft reveal a complex landscape of ridges and troughs, large hills and crater rims, rocks and boulders of various sizes and shapes, and surficial deposits, indicating a complex, multistage geologic history of the landing site. After the deposition of one or more bedrock units, depositional and erosional fluvial processes shaped much of the present landscape. Multiple erosional events are inferred on the basis of observations of numerous channels, different orientations of many streamlined tails from their associated knobs and hills, and superposition of lineations and streamlines. Medium- and small-scale features, interpreted to be related to late-stage drainage of floodwaters, are recognized in several areas at the landing site. Streamlined knobs and hills seen in Viking orbiter images support this inference, as they seem to be complex forms, partly erosional and partly depositional, and may also indicate a series of scouring and depositional events that, in some cases, further eroded or partially buried these landforms. Although features such as these are cited as evidence for catastrophic flooding at Ares Vallis, some of these features may also be ascribed to alternative primary or secondary depositional processes, such as glacial or mass-wasting processes. Close inspection of the landing site reveals rocks that are interpreted to be volcanic in origin and others that may be conglomeratic. If such sedimentary rocks are confirmed, fluvial processes have had a greater significance on Mars than previously thought. For the last several hundred million to few billion years, eolian processes have been dominant. Dunes and dune-like features, ventifacts, and deflation and exhumation features around several rocks probably are the most recent landforms. The relatively pristine nature of the overall landscape at the MPF site suggests weathering and erosion processes on Mars are exceptionally slow.

Ward, A.W.; Gaddis, L.R.; Kirk, R.L.; Soderblom, L.A.; Tanaka, K.L.; Golombek, M.P.; Parker, T.J.; Greeley, Ronald; Kuzmin, R.O.

1999-01-01

412

The actin-binding protein UNC-115 is an effector of Rac signaling during axon pathfinding in C-elegans  

E-print Network

the role of UNC-115 as a downstream cytoskeletal effector of Rac signaling in axon pathfinding. We show that unc-115 double mutants with ced-10 Rac, mig-2 Rac or unc-73 GEF but not with rac-2/3 Rac displayed synthetic axon pathfinding defects, and that loss...

Struckhoff, Eric Charles; Lundquist, Erik A.

2003-02-01

413

Inadequate evaluation and management of threats in Australia's Marine Parks, including the Great Barrier Reef, misdirect Marine conservation.  

PubMed

The magnificence of the Great Barrier Reef and its worthiness of extraordinary efforts to protect it from whatever threats may arise are unquestioned. Yet almost four decades after the establishment of the Great Barrier Reef Marine Park, Australia's most expensive and intensely researched Marine Protected Area, the health of the Reef is reported to be declining alarmingly. The management of the suite of threats to the health of the reef has clearly been inadequate, even though there have been several notable successes. It is argued that the failure to prioritise correctly all major threats to the reef, coupled with the exaggeration of the benefits of calling the park a protected area and zoning subsets of areas as 'no-take', has distracted attention from adequately addressing the real causes of impact. Australia's marine conservation efforts have been dominated by commitment to a National Representative System of Marine Protected Areas. In so doing, Australia has displaced the internationally accepted primary priority for pursuing effective protection of marine environments with inadequately critical adherence to the principle of having more and bigger marine parks. The continuing decline in the health of the Great Barrier Reef and other Australian coastal areas confirms the limitations of current area management for combating threats to marine ecosystems. There is great need for more critical evaluation of how marine environments can be protected effectively and managed efficiently. PMID:25358302

Kearney, Bob; Farebrother, Graham

2014-01-01

414

Pathfinder technologies for bold new missions. [U.S. research and development program for space exploration  

NASA Technical Reports Server (NTRS)

Project Pathfinder is a proposed U.S. Space Research and Technology program intended to enable bold new missions of space exploration. Pathfinder continues the advancement of technological capabilities and extends the foundation established under the Civil Space Technology Initiative, CSTI. By filling critical technological gaps, CSTI enhances access to Earth orbit and supports effective operations and science missions therein. Pathfinder, with a longer-term horizon, looks to a future that builds on Shuttle and Space Station and addresses technologies that support a range of exploration missions including: a return to the Moon to build an outpost; piloted missions to Mars; and continued scientific exploration of Earth and the other planets. The program's objective is to develop, within reasonable time frames, those emerging and innovative technologies that will make possible both new and enhanced missions and system concepts.

Sadin, Stanley R.; Rosen, Robert

1987-01-01

415

Photogrammetric analysis of horizon panoramas: The Pathfinder landing site in Viking orbiter images  

USGS Publications Warehouse

Tiepoint measurements, block adjustment techniques, and sunrise/sunset pictures were used to obtain precise pointing data with respect to north for a set of 33 IMP horizon images. Azimuth angles for five prominent topographic features seen at the horizon were measured and correlated with locations of these features in Viking orbiter images. Based on this analysis, the Pathfinder line/sample coordinates in two raw Viking images were determined with approximate errors of 1 pixel, or 40 m. Identification of the Pathfinder location in orbit imagery yields geological context for surface studies of the landing site. Furthermore, the precise determination of coordinates in images together with the known planet-fixed coordinates of the lander make the Pathfinder landing site the most important anchor point in current control point networks of Mars. Copyright 1999 by the American Geophysical Union.

Oberst, J.; Jaumann, R.; Zeitler, W.; Hauber, E.; Kuschel, M.; Parker, T.; Golombek, M.; Malin, M.; Soderblom, L.

1999-01-01

416

Preliminary Findings of the Photovoltaic Cell Calibration Experiment on Pathfinder Flight 95-3  

NASA Technical Reports Server (NTRS)

The objective of the photovoltaic (PV) cell calibration experiment for Pathfinder was to develop an experiment compatible with an ultralight UAV to predict the performance of PV cells at AM0, the solar spectrum in space, using the Langley plot technique. The Langley plot is a valuable technique for this purpose and requires accurate measurements of air mass (pressure), cell temperature, solar irradiance, and current-voltage(IV) characteristics with the cells directed normal to the direct ray of the sun. Pathfinder's mission objective (95-3) of 65,000 ft. maximum altitude, is ideal for performing the Langley plot measurements. Miniaturization of electronic data acquisition equipment enabled the design and construction of an accurate and light weight measurement system that meets Pathfinder's low payload weight requirements.

Vargas-Aburto, Carlos

1997-01-01

417

Coral reef evolution on rapidly subsiding margins  

USGS Publications Warehouse

A series of well-developed submerged coral reefs are preserved in the Huon Gulf (Papua New Guinea) and around Hawaii. Despite different tectonics settings, both regions have experienced rapid subsidence (2-6??m/ka) over the last 500??ka. Rapid subsidence, combined with eustatic sea-level changes, is responsible for repeated drowning and backstepping of coral reefs over this period. Because we can place quantitative constraints on these systems (i.e., reef drowning age, eustatic sea-level changes, subsidence rates, accretion rates, basement substrates, and paleobathymetry), these areas represent unique natural laboratories for exploring the roles of tectonics, reef accretion, and eustatic sea-level changes in controlling the evolution of individual reefs, as well as backstepping of the entire system. A review of new and existing bathymetric, radiometric, sedimentary facies and numerical modeling data indicate that these reefs have had long, complex growth histories and that they are highly sensitive, recording drowning not only during major deglaciations, but also during high-frequency, small-amplitude interstadial and deglacial meltwater pulse events. Analysis of five generalized sedimentary facies shows that reef drowning is characterized by a distinct biological and sedimentary sequence. Observational and numerical modeling data indicate that on precessional (20??ka) and sub-orbital timescales, the rate and amplitude of eustatic sea-level changes are critical in controlling initiation, growth, drowning or sub-aerial exposure, subsequent re-initiation, and final drowning. However, over longer timescales (> 100-500??ka) continued tectonic subsidence and basement substrate morphology influence broad scale reef morphology and backstepping geometries. Drilling of these reefs will yield greatly expanded stratigraphic sections compared with similar reefs on slowly subsiding, stable and uplifting margins, and thus they represent a unique archive of sea-level and climate changes, as well as a record of the response of coral reefs to these changes over the last six glacial cycles. ?? 2008 Elsevier B.V. All rights reserved.

Webster, J.M.; Braga, J.C.; Clague, D.A.; Gallup, C.; Hein, J.R.; Potts, D.C.; Renema, W.; Riding, R.; Riker-Coleman, K.; Silver, E.; Wallace, L.M.

2009-01-01

418

Coral reef evolution on rapidly subsiding margins  

NASA Astrophysics Data System (ADS)

A series of well-developed submerged coral reefs are preserved in the Huon Gulf (Papua New Guinea) and around Hawaii. Despite different tectonics settings, both regions have experienced rapid subsidence (2-6 m/ka) over the last 500 ka. Rapid subsidence, combined with eustatic sea-level changes, is responsible for repeated drowning and backstepping of coral reefs over this period. Because we can place quantitative constraints on these systems (i.e., reef drowning age, eustatic sea-level changes, subsidence rates, accretion rates, basement substrates, and paleobathymetry), these areas represent unique natural laboratories for exploring the roles of tectonics, reef accretion, and eustatic sea-level changes in controlling the evolution of individual reefs, as well as backstepping of the entire system. A review of new and existing bathymetric, radiometric, sedimentary facies and numerical modeling data indicate that these reefs have had long, complex growth histories and that they are highly sensitive, recording drowning not only during major deglaciations, but also during high-frequency, small-amplitude interstadial and deglacial meltwater pulse events. Analysis of five generalized sedimentary facies shows that reef drowning is characterized by a distinct biological and sedimentary sequence. Observational and numerical modeling data indicate that on precessional (20 ka) and sub-orbital timescales, the rate and amplitude of eustatic sea-level changes are critical in controlling initiation, growth, drowning or sub-aerial exposure, subsequent re-initiation, and final drowning. However, over longer timescales (> 100-500 ka) continued tectonic subsidence and basement substrate morphology influence broad scale reef morphology and backstepping geometries. Drilling of these reefs will yield greatly expanded stratigraphic sections compared with similar reefs on slowly subsiding, stable and uplifting margins, and thus they represent a unique archive of sea-level and climate changes, as well as a record of the response of coral reefs to these changes over the last six glacial cycles.

Webster, Jody M.; Braga, Juan Carlos; Clague, David A.; Gallup, Christina; Hein, James R.; Potts, Donald C.; Renema, Willem; Riding, Robert; Riker-Coleman, Kristin; Silver, Eli; Wallace, Laura M.

2009-03-01

419

Motoneuron axon pathfinding errors in zebrafish: Differential effects related to concentration and timing of nicotine exposure.  

PubMed

Nicotine exposure during embryonic stages of development can affect many neurodevelopmental processes. In the developing zebrafish, exposure to nicotine was reported to cause axonal pathfinding errors in the later born secondary motoneurons (SMNs). These alterations in SMN axon morphology coincided with muscle degeneration at high nicotine concentrations (15-30?M). Previous work showed that the paralytic mutant zebrafish known as sofa potato exhibited nicotine-induced effects onto SMN axons at these high concentrations but in the absence of any muscle deficits, indicating that pathfinding errors could occur independent of muscle effects. In this study, we used varying concentrations of nicotine at different developmental windows of exposure to specifically isolate its effects onto subpopulations of motoneuron axons. We found that nicotine exposure can affect SMN axon morphology in a dose-dependent manner. At low concentrations of nicotine, SMN axons exhibited pathfinding errors, in the absence of any nicotine-induced muscle abnormalities. Moreover, the nicotine exposure paradigms used affected the 3 subpopulations of SMN axons differently, but the dorsal projecting SMN axons were primarily affected. We then identified morphologically distinct pathfinding errors that best described the nicotine-induced effects on dorsal projecting SMN axons. To test whether SMN pathfinding was potentially influenced by alterations in the early born primary motoneuron (PMN), we performed dual labeling studies, where both PMN and SMN axons were simultaneously labeled with antibodies. We show that only a subset of the SMN axon pathfinding errors coincided with abnormal PMN axonal targeting in nicotine-exposed zebrafish. We conclude that nicotine exposure can exert differential effects depending on the levels of nicotine and developmental exposure window. PMID:25668718

Menelaou, Evdokia; Paul, Latoya T; Perera, Surangi N; Svoboda, Kurt R

2015-04-01

420

Coral reef community composition in the context of disturbance history on the Great Barrier Reef, Australia.  

PubMed

Much research on coral reefs has documented differential declines in coral and associated organisms. In order to contextualise this general degradation, research on community composition is necessary in the context of varied disturbance histories and the biological processes and physical features thought to retard or promote recovery. We conducted a spatial assessment of coral reef communities across five reefs of the central Great Barrier Reef, Australia, with known disturbance histories, and assessed patterns of coral cover and community composition related to a range of other variables thought to be important for reef dynamics. Two of the reefs had not been extensively disturbed for at least 15 years prior to the surveys. Three of the reefs had been severely impacted by crown-of-thorns starfish outbreaks and coral bleaching approximately a decade before the surveys, from which only one of them was showing signs of recovery based on independent surveys. We incorporated wave exposure (sheltered and exposed) and reef zone (slope, crest and flat) into our design, providing a comprehensive assessment of the spatial patterns in community composition on these reefs. Categorising corals into life history groupings, we document major coral community differences in the unrecovered reefs, compared to the composition and covers found on the undisturbed reefs. The recovered reef, despite having similar coral cover, had a different community composition from the undisturbed reefs, which may indicate slow successional processes, or a different natural community dominance pattern due to hydrology and other oceanographic factors. The variables that best correlated with patterns in the coral community among sites included the density of juvenile corals, herbivore fish biomass, fish species richness and the cover of macroalgae. Given increasing impacts to the Great Barrier Reef, efforts to mitigate local stressors will be imperative to encouraging coral communities to persist into the future. PMID:24983747

Graham, Nicholas A J; Chong-Seng, Karen M; Huchery, Cindy; Januchowski-Hartley, Fraser A; Nash, Kirsty L

2014-01-01

421

Dynamic Stability of Coral Reefs on the West Australian Coast  

PubMed Central

Monitoring changes in coral cover and composition through space and time can provide insights to reef health and assist the focus of management and conservation efforts. We used a meta-analytical approach to assess coral cover data across latitudes 10–35°S along the west Australian coast, including 25 years of data from the Ningaloo region. Current estimates of coral cover ranged between 3 and 44% in coral habitats. Coral communities in the northern regions were dominated by corals from the families Acroporidae and Poritidae, which became less common at higher latitudes. At Ningaloo Reef coral cover has remained relatively stable through time (?28%), although north-eastern and southern areas have experienced significant declines in overall cover. These declines are likely related to periodic disturbances such as cyclones and thermal anomalies, which were particularly noticeable around 1998/1999 and 2010/2011. Linear mixed effects models (LME) suggest latitude explains 10% of the deviance in coral cover through time at Ningaloo. Acroporidae has decreased in abundance relative to other common families at Ningaloo in the south, which might be related to persistence of more thermally and mechanically tolerant families. We identify regions where quantitative time-series data on coral cover and composition are lacking, particularly in north-western Australia. Standardising routine monitoring methods used by management and research agencies at these, and other locations, would allow a more robust assessment of coral condition and a better basis for conservation of coral reefs. PMID:23922829

Speed, Conrad W.; Babcock, Russ C.; Bancroft, Kevin P.; Beckley, Lynnath E.; Bellchambers, Lynda M.; Depczynski, Martial; Field, Stuart N.; Friedman, Kim J.; Gilmour, James P.; Hobbs, Jean-Paul A.; Kobryn, Halina T.; Moore, James A. Y.; Nutt, Christopher D.; Shedrawi, George; Thomson, Damian P.; Wilson, Shaun K.

2013-01-01

422

Climate Change on Mars Inferred from Erosion Rates at the Mars Pathfinder Landing Site  

NASA Technical Reports Server (NTRS)

The observation that the Mars Pathfinder landing site probably looks very similar to when it was deposited by catastrophic floods some 1.8-3.5 Ga allows quantitative constraints to be placed on the rate of change at the landing site since that time. When combined with interpretations of data recently returned by the Mars Pathfinder and Global Surveyor missions and perspectives drawn from 20 years of analysis and interpretation of Viking data, these observations and inferences suggest an early warmer and wetter environment with vastly different erosion rates and a major climatic change on Mars. Additional information is contained in the original extended abstract.

Golombek, M. P.; Bridges, N. T.

1999-01-01

423

MARS PATHFINDER ENTRY VEHICLE MATE TO CRUISE STAGE COMPLETED IN SAEF-2  

NASA Technical Reports Server (NTRS)

Work stands in KSC's Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) are pulled away to reveal the Mars Pathfinder lander and cruise stage mated together. The compact spacecraft still must be fueled and then balanced. It is scheduled to be mated with its upper stage booster around Nov. 15 and then delivered to Launch Complex 17 on Cape Canaveral Air Station around the 21st of November. The second of two U.S. missions to Mars being launched this year, the Mars Pathfinder is targeted for liftoff aboard a Delta II expendable launch vehicle at the beginning of a 24-day launch period opening Dec. 2.

1996-01-01

424

The SKA and its pathfinders in the next decade: synergies with the TMT  

NASA Astrophysics Data System (ADS)

The next decade will be extremely exciting for centimeter- and meter-wave radio astronomy. Large new facilities such as ASKAP, LOFAR and MeerKAT, as well as major retrofits to existing facilities such as the JVLA and WSRT, are under construction or have begun operations. While revolutionary in and of themselves, these facilities are also important pathfinders to the SKA, whose construction will begin towards the end of this decade. This talk will review the key science that will be delivered by the SKA pathfinders as well as that anticipated with SKA Phase One (2018-2023) and Phase Two (>2023), with a focus on potential synergies with the TMT.

Spekkens, Kristine

2014-07-01

425

Mineralogic and compositional properties of Martian soil and dust: results from Mars Pathfinder  

USGS Publications Warehouse

Mars Pathfinder obtained multispectral, elemental, magnetic, and physical measurements of soil and dust at the Sagan Memorial Station during the course of its 83 sol mission. We describe initial results from these measurements, concentrating on multispectral and elemental data, and use these data, along with previous Viking, SNC meteorite, and telescopic results, to help constrain the origin and evolution of Martian soil and dust. We find that soils and dust can be divided into at least eight distinct spectral units, based on parameterization of Imager for Mars Pathfinder (IMP) 400 to 1000 nm multispectral images. The most distinctive spectral parameters for soils and dust are the reflectivity in the red, the red/blue reflectivity ratio, the near-IR spectral slope, and the strength of the 800 to 1000 nm absorption feature. Most of the Pathfinder spectra are consistent with the presence of poorly crystalline or nanophase ferric oxide(s), sometimes mixed with small but varying degrees of well-crystalline ferric and ferrous phases. Darker soil units appear to be coarser-grained, compacted, and/or mixed with a larger amount of dark ferrous materials relative to bright soils. Nanophase goethite, akaganeite, schwertmannite, and maghemite are leading candidates for the origin of the absorption centered near 900 nm in IMP spectra. The ferrous component in the soil cannot be well-constrained based on IMP data. Alpha proton X-ray spectrometer (APXS) measurements of six soil units show little variability within the landing site and show remarkable overall similarity to the average Viking-derived soil elemental composition. Differences exist between Viking and Pathfinder soils, however, including significantly higher S and Cl abundances and lower Si abundances in Viking soils and the lack of a correlation between Ti and Fe in Pathfinder soils. No significant linear correlations were observed between IMP spectral properties and APXS elemental chemistry. Attempts at constraining the mineralogy of soils and dust using normative calculations involving mixtures of smectites and silicate and oxide minerals did not yield physically acceptable solutions. We attempted to use the Pathfinder results to constrain a number of putative soil and dust formation scenarios, including palagonitization and acid-fog weathering. While the Pathfinder soils cannot be chemically linked to the Pathfinder rocks by palagonitization, this study and McSween et al. [1999] suggest that palagonitic alteration of a Martian basaltic rock, plus mixture with a minor component of locally derived andesitic rock fragments, could be consistent with the observed soil APXS and IMP properties.

Bell, J.F., III; McSween, H.Y., Jr.; Crisp, J.A.; Morris, R.V.; Murchie, S.L.; Bridges, N.T.; Johnson, J.R.; Britt, D.T.; Golombek, M.P.; Moore, H.J.; Ghosh, A.; Bishop, J.L.; Anderson, R.C.; Brückner, J.; Economou, T.; Greenwood, J.P.; Gunnlaugsson, H.P.; Hargraves, R.M.; Hviid, S.; Knudsen, J.M.; Madsen, M.B.; Reid, R.; Rieder, R.; Soderblom, L.

2000-01-01

426

Observation of early photons from gamma-ray bursts with the Lomonosov / UFFO-pathfinder  

NASA Astrophysics Data System (ADS)

UFFO-pathfinder is a pioneering space mission to observe the early evolution of Gamma-ray Bursts using a fast slewing strategy. It consists of the Slewing Mirror Telescope, for rapid pointing at UV/optical wavelengths and the UFFO Burst Alert and Trigger Telescope. It has a total weight of ˜ 20 kg and will be launched on-board the Russian Lomonosov satellite at the end of 2015. The instrumental details of UFFO-pathfinder and its performance are discussed briefly here.

Jeong, S.; Brandt, S.; Budtz-Jørgensen, C.; Castro-Tirado, A. J.; Chen, P.; Connell, P.; Eyles, C.; Huang, M.-H. A.; Kim, J. E.; Kim, M. B.; Kim, S.-W.; Lee, J.; Lim, H.; Liu, T.-C.; Nam, J. W.; Park, H. W.; Park, I. H.; Panasyuk, M. I.; Reglero, V.; Ripa, J.; Rodrigo, J. M.; Svertilov, S.; Vedenkin, N.; Yashin, I.

2014-12-01

427

Observations by the Mars 1994 orbiter and possible correlations with Mars Pathfinder  

NASA Technical Reports Server (NTRS)

The Mars '94 spacecraft will still be operational when Mars Pathfinder begins its observations. While it will probably not be possible to detect the lander directly, the terrain, including the landing error ellipse, can be covered in high resolution (10 m) in various color bands. The stereo capability of the high resolution camera will provide a three-dimensional terrain map. The landing site of Pathfinder could possibly be chosen so that correlated observations of IMP and the remote sensing instruments onboard Mars '94 may be possible. We will discuss this scenario based on the presently adopted Mars '94 orbit and resulting enhancements stemming from correlations of data obtained by both spacecraft.

Keller, H. Uwe

1994-01-01

428

Wonders of the Living Reef The Invertebrates  

Microsoft Academic Search

The living reef is a realm of wonders. With a first look at a living reef, one is overwhelmed with the diversity in color and shape of the corals and fishes. But beneath this surface is an even more wondrous world, one of bizarre, alien creatures, some of which hardly resemble living animals. These \\

Scott Johnson

429

Reefs and Learning: Education Evaluation Techniques  

ERIC Educational Resources Information Center

Marine education research designs are discussed, and student learning outcomes while monitoring a coral reef is evaluated. Changes in environmental knowledge and attitudes, ecological intention to act, and direct reef experience were investigated. Differences between student pre-test and the post-test responses were observed, and analysis is…

Stepath, Carl M.

2006-01-01

430

Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve  

NSDL National Science Digital Library

Describes the unique Northwestern Hawaiian Islands (NWHI) Ecosystem Reserve. Provides resources focused on NWHI coral reef ecosystems, and introductions to reef research, management and protection activities. Educational outreach includes: teacher workshops; student activities, and a Discovery Center in Hilo, Hawaii that features exhibits and activities for schools and the public.

431

Silurian pinnacle reefs of the Canadian Arctic  

SciTech Connect

Pinnacle reefs are commonly an attractive target for oil exploration because they are usually porous carbonate bodies entombed in impervious, deep-water shales that provide both the source and the seal for hydrocarbons. Silurian pinnacle reefs, the first described in the Canadian Arctic Archipelago, are exposed on Ellesmere and Devon Islands. Two main reef trends occur, one of early middle Llandovery to middle Ludlow age and a second of middle Ludlow to Late Silurian or Early Devonian age. Reefs of both phases contain lime mudstone cores: some are stromatactoid-rich and others consist predominantly of microbialite-rich lime mudstone or microbial boundstone. Facies sequences of both reef phases show evidence of upward-shallowing overall, but, in the older reefs, isochronous capping facies are dominated either by coral-mirian or by stromatoporoid boundstone and floatstone. This difference perhaps reflects variation in wave stress and apparent ability of a few corals,thickly encrusted by or associated with microbial boundstone and skeletal algae, to withstand greater wave energy than a stromatoporoid-coral-rich reef community. These reefs constitute one of the bright prospects of hydrocarbon exploration in rocks of the Franklinian succession. 43 refs., 9 figs.

De Freitas, T.A.; Dixon, O.A. (Univ. of Ottawa, Ontario (Canada)); Mayr, U. (Institute of Sedimentary and Petroleum Geology, Alberta (Canada))

1993-04-01

432

Preliminary observations on coral reef plankton  

Microsoft Academic Search

ABSTBRCT Plankton collections near coral reefs were made by hand-towing nets while swimming and by using a suction device for sampling caves. Plankton in sheltered areas was con- sidcrably different from that in nonsheltered areas; some plankton forms maintained position near coral reefs, indicating that the terms planktonic and epibenthic may represent extremes of a behavior continuum. Copepods were observed

ALAN R. EMERY

1968-01-01

433

Disease of coral and coral reef fishes  

USGS Publications Warehouse

The Department of the Interior protects sensitive habitats amounting to about 3,600,000 acres of coral reefs and other submerged lands. These reefs are important ecosystems in 13 National Wildlife Refuges, 10 National Parks and in certain territorial waters such as the Wake Atoll.

Panek, Frank

2008-01-01

434

Reproductive ecology of Caribbean reef corals  

Microsoft Academic Search

The last decade has seen a resurgence of interest in the processes of sexual reproduction by scleractinian reef corals. Earlier investigations had focused fortuitously on brooding (planulating) species, which resulted in the general misconception that brooding was the main form of larval development of reef corals. More recent work on Indo-Pacific species has shown broadcast spawning and short annual reproductive

Alina M. Szmant

1986-01-01

435

Sandstone Strata in Capitol Reef National Park  

USGS Multimedia Gallery

A detail view of some sandstone strata within Capitol Reef National Park. Capitol Reef is primarily made up of sandstone formations within the Waterpocket Fold, monocline that extends nearly 100 miles. A monocline is a step-like fold in rock strata that can resemble an enormous wrinkle in the earth....

436

Coral Reef Conservation in Marine Protected Areas  

E-print Network

Coral Reef Conservation in Marine Protected Areas A Case Study of Parque Nacional del Este 22203, USA Telephone: (703) 841-4860 Coral Reef Conservation in Marine Protected Areas: A Case Study, Dominican Republic Part 3 of 3 in a Series on Science Tools for Marine Park Management Edited by Mark

Greer, Lisa

437

REEF MANAGER'S GUIDE TO CORAL BLEACHING  

EPA Science Inventory

A Reef Manager's Guide to Coral Bleaching is the result of a collaborative effort by over 50 scientists and managers to: (1) engage in information-sharing in the areas of coral reef science and management for climate change and coral bleaching; and (2) compile a management tool ...

438

Subtropical Biotic Fringing Reefs as Ecological Laboratories.  

ERIC Educational Resources Information Center

Describes a 16-week course in marine biology involving a class-coordinated investigation of a subtropical biotic fringing reef of Hawaii. Describes in detail the development of preliminary hypotheses regarding general cause-effect relationships on the reef, and the exploration of specific areas, such as chemical or physical factors. (CS)

Hunt, Jeffrey W.

1980-01-01

439

Along-Track Reef Imaging System (ATRIS)  

USGS Publications Warehouse

"Along-Track Reef Imaging System (ATRIS)" describes the U.S. Geological Survey's Along-Track Reef Imaging System, a boat-based sensor package for rapidly mapping shallow water benthic environments. ATRIS acquires high resolution, color digital images that are accurately geo-located in real-time.

Brock, John; Zawada, Dave

2006-01-01

440

Artificial Reefs--A Coastal Classroom Project.  

ERIC Educational Resources Information Center

Discusses the construction of artificial reefs for such uses as commercial fishing and recreational boating. Describes a class project in which students construct a small artificial reef and observe the changes over time in terms of temperature, salinity, flora and fauna. (TW)

Dindo, John J.

1986-01-01

441

Status of Pacific Island coral reef fisheries  

Microsoft Academic Search

It is difficult to determine the status of fisheries on Pacific Islands coral reefs. The region is economically undeveloped, sparsely populated and its coral reefs are scattered over a vast area. Resultant constraints on monitoring and investigation mean that quantitative information is rare. The few available quantitative indicators are summarised here alongside opinions based on extensive practical experience. Most anecdotal

Tim Adams; Paul Dalzell; Richard Farman

442

Bathymetric distribution of foraminifera in Jamaican reef environments  

SciTech Connect

Recent foraminifera inhabiting Jamaican north-coast fringing reefs display variations in distributional patterns that are related to bathymetry and reef morphology. Sediment samples containing foraminifera were collected along a profile that traversed the back reef (depth 1-2 m), fore-reef terrace (3-15 m), fore-reef escarpment (15-27 m), fore-reef slope (30-55 m), and upper deep fore reef (70 m). Approximately 150 species distributed among 80 genera were identified from the samples. Preliminary analyses indicate that diversity values (S, H') are lowest on the fore-reef terrace (79, 3.0, respectively), increase similarly in back-reef and fore-reef escarpment and slope settings (93, 3.4), and are highest on the deep fore reef (109, 3.7). Larger groupings (suborders) exhibit distinct bathymetric trends with miliolids occurring more commonly in back-reef (comprising 51% of the fauna) than in fore-reef (28%) zones, whereas agglutinated and planktonic species occur more commonly in deeper reef (> 15 m, 9% and 4%, respectively) than in shallower reef zones (< 15 m, 3%, and 0.5%, respectively). Among the more common species Amphistegina gibbosa (Rotolina) is much more abundant in fore-reef (3%) environments, and Sorites marginalis (Miliolina) occurs almost exclusively in the back reef, where it comprises 5.5% of the fauna. Q-mode cluster analysis, involving all species collected, enabled the delineation of back-reef, shallow fore-reef, and deeper fore-reef biofacies, also indicating the potential utility of foraminiferal distributions in detailed paleoenvironment interpretations of ancient reef settings.

Martin, R.E.; Liddell, W.D.

1985-02-01

443

National Center for Caribbean Coral Reef Research  

NSDL National Science Digital Library

A number of research centers are concerned with the state of the world's coral reefs, and the National Center for Caribbean Coral Reef Research (NCORE) is one such center of scholarly excellence. Located at the University of Miami, NCORE is primarily concerned with "the analysis and predication of coral reef resilience". On their site, visitors can learn about some of their primary research initiatives, such as their work on the Florida reef tract and on tracking the effects of climate change on the reef communities. The general public will also find their digital map series quite useful as well. In this section, users can examine a number of complex digital maps and images that provide information about the state of coral cover around Puerto Rico, South Florida, and the Bahamas.

444

Coral Reef Information System: Discover NOAA's Data  

NSDL National Science Digital Library

Part of the National Oceanic and Atmospheric Administration's Coral Reef Information System (CoRIS), this Web site is "designed to be a single point of access to NOAA coral reef information and data products, especially those derived from NOAA's Coral Reef Initiative Program." With Discover NOAA's Data, users can access information by a text search of metadata records, or by a spatial search using an Arc IMS application. The two approaches share many of the same data sets. With the text search, users may search NOAA coral reef information by title, author, keyword, etc. The map program includes "over 19,000 aerial photos, 400 preview navigational charts, tide stations, paleoclimatological studies, photo mosaics, coral reef monitoring, bleaching reports, and more." The site provides numerous help features for both search methods.

445

Parrotfish abundance and selective corallivory on a Belizean coral reef  

E-print Network

Parrotfish abundance and selective corallivory on a Belizean coral reef Randi D. Rotjan *, Sara M of coral reef communities because they consume macroalgae that would otherwise outcompete reef grazing by parrotfish on particular coral species, differences in grazing incidence among reef habitats

Lewis, Sara

446

Science and management of coral reefs: problems and prospects  

Microsoft Academic Search

It should be recognised that many principles of reef management do not need further research, as they involve changing human behaviour and activities in order to remove or reduce impacts on reefs. Much of the time of a reef manager is taken up with social, economic and political issues: the integration of reef management into broad coastal zone management objectives;

S. M. Wells

1995-01-01

447

Pressures and effects on the Great Barrier Reef lagoon  

E-print Network

not presented) Impacts on and responses of seagrasses in the Great Barrier Reef - issues for management W Lee) ecosystem relevant to management are reviewed. Reefs per se only make up a small fraction ( sea, bounded by and encompassing to varymg degrees a porous matrix of coral reefs. Reef area

Marsh, Helene

448

-Congressional Policy Brief -United States Coral Reef Task Force  

E-print Network

and jurisdictions in coral reef regions, and helped its members launch new actions to protect and manage reef- Congressional Policy Brief - United States Coral Reef Task Force "NOAA, on behalf of the Department of Commerce, is honored to serve as Co-Chair of the U.S. Coral Reef Task Force, along

449

A Global Estimate of the Number of Coral Reef Fishers.  

PubMed

Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest that slightly over a quarter of the world's small-scale fishers fish on coral reefs, and half of all coral reef fishers are in Southeast Asia. Coral reefs evidently support the socio-economic well-being of numerous coastal communities. By quantifying the number of people who are employed as reef fishers, we provide decision-makers with an important input into planning for sustainable coral reef fisheries at the appropriate scale. PMID:23840327

Teh, Louise S L; Teh, Lydia C L; Sumaila, U Rashid

2013-01-01

450

Climate Change, Human Impacts, and the Resilience of Coral Reefs  

Microsoft Academic Search

The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing

T. P. Hughes; A. H. Baird; D. R. Bellwood; M. Card; S. R. Connolly; C. Folke; R. Grosberg; O. Hoegh-Guldberg; J. B. C. Jackson; J. Kleypas; J. M. Lough; P. Marshall; M. Nyström; S. R. Palumbi; J. M. Pandolfi; B. Rosen; J. Roughgarden

2003-01-01

451

A Global Estimate of the Number of Coral Reef Fishers  

PubMed Central

Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest