75 FR 76943 - Regulated Navigation Area; Hudson River South of the Troy Locks, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-10

...-AA11 Regulated Navigation Area; Hudson River South of the Troy Locks, NY AGENCY: Coast Guard, DHS... Navigation Area (RNA) on the navigable waters of the Hudson River in New York, south of the Troy Locks. This... within the waters of the Hudson River south of the Troy Locks when ice is a threat to navigation. DATES...

Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route

PubMed Central

Inoue, Jun; Yamazaki, Akira; Ono, Jun; Dethloff, Klaus; Maturilli, Marion; Neuber, Roland; Edwards, Patti; Yamaguchi, Hajime

2015-01-01

During ice-free periods, the Northern Sea Route (NSR) could be an attractive shipping route. The decline in Arctic sea-ice extent, however, could be associated with an increase in the frequency of the causes of severe weather phenomena, and high wind-driven waves and the advection of sea ice could make ship navigation along the NSR difficult. Accurate forecasts of weather and sea ice are desirable for safe navigation, but large uncertainties exist in current forecasts, partly owing to the sparse observational network over the Arctic Ocean. Here, we show that the incorporation of additional Arctic observations improves the initial analysis and enhances the skill of weather and sea-ice forecasts, the application of which has socioeconomic benefits. Comparison of 63-member ensemble atmospheric forecasts, using different initial data sets, revealed that additional Arctic radiosonde observations were useful for predicting a persistent strong wind event. The sea-ice forecast, initialised by the wind fields that included the effects of the observations, skilfully predicted rapid wind-driven sea-ice advection along the NSR. PMID:26585690

The Rapidly Diminishing Arctic ice Cover and its Potential Impact on Navy Operational Considerations

NASA Astrophysics Data System (ADS)

Muench, R. D.; Conlon, D.; Lamb, D.

2001-12-01

Observations made from U.S. Navy Fleet submarines during the 1990s have revealed a dramatic decrease in thickness, when compared to historical values, of the central Arctic Ocean pack ice cover. Estimates of this decrease have been as high as 40%. Remote sensing observations have shown a coincident decrease in the areal extent of the pack. The areal decrease has been especially apparent during winter. The overall loss of ice appears to have accelerated over the past decade, raising the possibility that the Northwest Passage and the Northern Sea Route may become seasonally navigable on a regular basis in the coming decade. The ice loss has been most evident in the peripheral seas and continental shelf areas. For example, during winter 2000-2001 the Bering Sea was effectively ice-free, with strong and immediate impacts on the surrounding indigenous populations. Lessening of the peripheral pack ice cover will presumably, lead to accelerated development of the resource-rich regions that surround the deep, central Arctic Ocean basin. This raises potential issues with respect to national security and commercial interests, and has implicit strategic concerns for the Navy. The timeline for a significantly navigable Arctic may extend decades into the future; however, operational requirements must be identified in the nearer term to ensure that the necessary capabilities exist when future Arctic missions do present themselves. A first step is to improve the understanding of the coupled atmosphere/ice/ocean system. Current environmental measurement and prediction, including Arctic weather and ice prediction, shallow water acoustic performance prediction, dynamic ocean environmental changes and data to support navigation is inadequate to support sustained naval operations in the Arctic. A new focus on data collection is required in order to measure, map, monitor and model Arctic weather, ice and oceanographic conditions.

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2013 CFR

2013-07-01

... maintain an exact position because strong or varying currents, heavy seas, ice, and collisions with vessels... the navigating bridge is operated to determine if the steering equipment is operating properly under manual control, unless the vessel has been steered under manual control from the navigating bridge within...

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2014 CFR

2014-07-01

... maintain an exact position because strong or varying currents, heavy seas, ice, and collisions with vessels... the navigating bridge is operated to determine if the steering equipment is operating properly under manual control, unless the vessel has been steered under manual control from the navigating bridge within...

Long-Endurance, Ice-capable Autonomous Seagliders

NASA Astrophysics Data System (ADS)

Lee, C. M.; Gobat, J. I.; Shilling, G.; Curry, B.

2012-12-01

Autonomous Seagliders capable of extended (many months) operation in ice-covered waters have been developed and successfully employed as part of the US Arctic Observing Network. Seagliders operate routinely in lower-latitude oceans for periods of up to 9 months to provide persistent sampling in difficult, remote conditions, including strong boundary currents and harsh wintertime subpolar seas. The Arctic Observing Network calls for sustained occupation of key sections within the Arctic Ocean and across the critical gateways that link the Arctic to lower-latitude oceans, motivating the extension of glider technologies to permit operation in ice-covered waters. When operating in open water, gliders rely on GPS for navigation and Iridium satellite phones for data and command telemetry. Ice cover blocks access to the sea surface and thus prevents gliders from using these critical services. When operating under ice, ice-capable Seagliders instead navigate by trilateration from an array of RAFOS acoustic sound sources and employ advanced autonomy to make mission-critical decisions (previously the realm of the human pilot) and identify and exploit leads in the ice to allow intermittent communication through Iridium. Davis Strait, one of the two primary pathways through which Arctic waters exit into the subpolar North Atlantic, provided a convenient site for development of ice-capable Seagliders at a location where the resulting measurements could greatly augment the existing observing system. Initial testing of 780 Hz RAFOS sources in Davis Strait, substantiated by the performance of the operational array, indicates effective ranges of 100-150 km in ice-covered waters. Surface ducting and reflection off the ice bottom significantly degrade the range from the 500+ km expected in ice-free conditions. Comparisons between GPS and acoustically-derived positions collected during operations in ice-free conditions suggest 1-2 km uncertainty in the acoustically-derived positions. The first successful section across the ice-covered Davis Strait occurred in 2006, while the first full mission took place September - February 2008. Mission duration was 25 weeks, with over 800 km of under-ice transit over 51 days. The glider was able to identify and surface through leads 10 times during under-ice operations. Most recently, a pair of successful missions collected continuous sections across Davis Strait from October 2010 through June 2011, including operations between January and June, when the strait was nearly entirely ice-covered and the glider rarely gained access to the surface. These missions provide the first year-round time series of high-resolution sections across Davis Strait. In the Antarctic, ice-capable Seagliders successfully transited beneath a 40-km ice bridge and self-extracted after being carried beneath the Ross ice shelf during missions conducted without the support of an acoustic navigation array. Ice-capable Seagliders can provide sustainable, continuous occupation of critical sections in ice-covered regions, including the marginal ice zone, with typical horizontal resolution of 3 km and routine sampling of the important, but hazardous, region near the ice-ocean interface. Future directions include development of basin-scale acoustic navigation ('underwater GPS' for the Arctic) and use of existing high-frequency acoustic communications for short-range data transfer.

Long-Endurance, Ice-capable Autonomous Seagliders

NASA Astrophysics Data System (ADS)

Lee, Craig; Gobat, Jason; Shilling, Geoff; Curry, Beth

2013-04-01

Autonomous Seagliders capable of extended (many months) operation in ice-covered waters have been developed and successfully employed as part of the US Arctic Observing Network. Seagliders operate routinely in lower-latitude oceans for periods of up to 9 months to provide persistent sampling in difficult, remote conditions, including strong boundary currents and harsh wintertime subpolar seas. The Arctic Observing Network calls for sustained occupation of key sections within the Arctic Ocean and across the critical gateways that link the Arctic to lower-latitude oceans, motivating the extension of glider technologies to permit operation in ice-covered waters. When operating in open water, gliders rely on GPS for navigation and Iridium satellite phones for data and command telemetry. Ice cover blocks access to the sea surface and thus prevents gliders from using these critical services. When operating under ice, ice-capable Seagliders instead navigate by trilateration from an array of RAFOS acoustic sound sources and employ advanced autonomy to make mission-critical decisions (previously the realm of the human pilot) and identify and exploit leads in the ice to allow intermittent communication through Iridium. Davis Strait, one of the two primary pathways through which Arctic waters exit into the subpolar North Atlantic, provided a convenient site for development of ice-capable Seagliders at a location where the resulting measurements could greatly augment the existing observing system. Initial testing of 780 Hz RAFOS sources in Davis Strait, substantiated by the performance of the operational array, indicates effective ranges of 100-150 km in ice-covered waters. Surface ducting and reflection off the ice bottom significantly degrade the range from the 500+ km expected in ice-free conditions. Comparisons between GPS and acoustically-derived positions collected during operations in ice-free conditions suggest 1-2 km uncertainty in the acoustically-derived positions. The first successful section across the ice-covered Davis Strait occurred in 2006, while the first full mission took place September - February 2008. Mission duration was 25 weeks, with over 800 km of under-ice transit over 51 days. The glider was able to identify and surface through leads 10 times during under-ice operations. Most recently, a pair of successful missions collected continuous sections across Davis Strait from October 2010 through June 2011, including operations between January and June, when the strait was nearly entirely ice-covered and the glider rarely gained access to the surface. These missions provide the first year-round time series of high-resolution sections across Davis Strait. In the Antarctic, ice-capable Seagliders successfully transited beneath a 40-km ice bridge and self-extracted after being carried beneath the Ross ice shelf during missions conducted without the support of an acoustic navigation array. Ice-capable Seagliders can provide sustainable, continuous occupation of critical sections in ice-covered regions, including the marginal ice zone, with typical horizontal resolution of 3 km and routine sampling of the important, but hazardous, region near the ice-ocean interface. Future directions include development of basin-scale acoustic navigation ('underwater GPS' for the Arctic) and use of existing high-frequency acoustic communications for short-range data transfer.

The Secret of the Svalbard Sea Ice Barrier

NASA Technical Reports Server (NTRS)

Nghiem, Son V.; Van Woert, Michael L.; Neumann, Gregory

2004-01-01

An elongated sea ice feature called the Svalbard sea ice barrier rapidly formed over an area in the Barents Sea to the east of Svalbard posing navigation hazards. The secret of its formation lies in the bottom bathymetry that governs the distribution of cold Arctic waters masses, which impacts sea ice growth on the water surface.

75 FR 8486 - Regulated Navigation Area; Hudson River south of the Troy Locks, New York

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-25

...-AA11 Regulated Navigation Area; Hudson River south of the Troy Locks, New York AGENCY: Coast Guard, DHS... area on the navigable waters of the Hudson River south of the Troy Locks. This regulated navigation... Hudson River south of the Troy locks when ice conditions are 8 inches or greater unless authorized by the...

76 FR 8654 - Regulated Navigation Area; Hudson River South of the Troy Locks, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-15

...-AA11 Regulated Navigation Area; Hudson River South of the Troy Locks, NY AGENCY: Coast Guard, DHS... navigable waters of the Hudson River in New York, south of the Troy Locks. This action is necessary to... Hudson River south of the Troy Locks when ice is a threat to navigation. DATES: This rule is effective in...

47 CFR 80.329 - Safety signals and messages.

Code of Federal Regulations, 2010 CFR

2010-10-01

... cyclones, dangerous ice, dangerous wrecks, or any other imminent danger to marine navigation must be... is about to transmit a message concerning the safety of navigation or giving important meteorological...

47 CFR 80.329 - Safety signals and messages.

Code of Federal Regulations, 2011 CFR

2011-10-01

... cyclones, dangerous ice, dangerous wrecks, or any other imminent danger to marine navigation must be... is about to transmit a message concerning the safety of navigation or giving important meteorological...

SONARC: A Sea Ice Monitoring and Forecasting System to Support Safe Operations and Navigation in Arctic Seas

NASA Astrophysics Data System (ADS)

Stephenson, S. R.; Babiker, M.; Sandven, S.; Muckenhuber, S.; Korosov, A.; Bobylev, L.; Vesman, A.; Mushta, A.; Demchev, D.; Volkov, V.; Smirnov, K.; Hamre, T.

2015-12-01

Sea ice monitoring and forecasting systems are important tools for minimizing accident risk and environmental impacts of Arctic maritime operations. Satellite data such as synthetic aperture radar (SAR), combined with atmosphere-ice-ocean forecasting models, navigation models and automatic identification system (AIS) transponder data from ships are essential components of such systems. Here we present first results from the SONARC project (project term: 2015-2017), an international multidisciplinary effort to develop novel and complementary ice monitoring and forecasting systems for vessels and offshore platforms in the Arctic. Automated classification methods (Zakhvatkina et al., 2012) are applied to Sentinel-1 dual-polarization SAR images from the Barents and Kara Sea region to identify ice types (e.g. multi-year ice, level first-year ice, deformed first-year ice, new/young ice, open water) and ridges. Short-term (1-3 days) ice drift forecasts are computed from SAR images using feature tracking and pattern tracking methods (Berg & Eriksson, 2014). Ice classification and drift forecast products are combined with ship positions based on AIS data from a selected period of 3-4 weeks to determine optimal vessel speed and routing in ice. Results illustrate the potential of high-resolution SAR data for near-real-time monitoring and forecasting of Arctic ice conditions. Over the next 3 years, SONARC findings will contribute new knowledge about sea ice in the Arctic while promoting safe and cost-effective shipping, domain awareness, resource management, and environmental protection.

Meteorological-physical Limitations of Icing in the Atmosphere

NASA Technical Reports Server (NTRS)

Findeisen, W

1939-01-01

The icing hazard can, in most cases, be avoided by correct execution of the flights according to meteorological viewpoints and by meteorologically correct navigation (horizontal and, above all, vertical). The zones of icing hazard are usually narrowly confined. Their location can be ascertained with, in most cases, sufficient accuracy before take-off.

Mapping of sea ice and measurement of its drift using aircraft synthetic aperture radar images

NASA Technical Reports Server (NTRS)

Leberl, F.; Bryan, M. L.; Elachi, C.; Farr, T.; Campbell, W.

1979-01-01

Side-looking radar images of Arctic sea ice were obtained as part of the Arctic Ice Dynamics Joint Experiment. Repetitive coverages of a test site in the Arctic were used to measure sea ice drift, employing single images and blocks of overlapping radar image strips; the images were used in conjunction with data from the aircraft inertial navigation and altimeter. Also, independently measured, accurate positions of a number of ground control points were available. Initial tests of the method were carried out with repeated coverages of a land area on the Alaska coast (Prudhoe). Absolute accuracies achieved were essentially limited by the accuracy of the inertial navigation data. Errors of drift measurements were found to be about + or - 2.5 km. Relative accuracy is higher; its limits are set by the radar image geometry and the definition of identical features in sequential images. The drift of adjacent ice features with respect to one another could be determined with errors of less than + or - 0.2 km.

Marine geodesy a multipurpose approach to solve oceanic problems. [including submersible navigation under iced seas, demarcation and determination of boundaries in deep ocean, tsunamis, and ecology

NASA Technical Reports Server (NTRS)

Saxena, N.

1974-01-01

Various current and future problem areas of marine geodesy are identified. These oceanic problem areas are highly diversified and include submersible navigation under ice seas, demarcation and determination of boundaries in deep ocean, tsunamis, ecology, etc., etc. Their achieved as well as desired positional accuracy estimates, based upon publications and discussions, are also given. A multipurpose approach to solve these problems is described. An optimum configuration of an ocean-bottom control-net unit is provided.

Lunar and Lagrangian Point L1 L2 CubeSat Communication and Navigation Considerations

NASA Technical Reports Server (NTRS)

Schaire, Scott; Wong, Yen F.; Altunc, Serhat; Bussey, George D.; Shelton, Marta; Folta, Dave; Gramling, Cheryl; Celeste, Peter; Anderson, Mike; Perrotto, Trish;

NWS Alaska Sea Ice Program: Operations and Decision Support Services

NASA Astrophysics Data System (ADS)

Schreck, M. B.; Nelson, J. A., Jr.; Heim, R.

2015-12-01

The National Weather Service's Alaska Sea Ice Program is designed to service customers and partners operating and planning operations within Alaska waters. The Alaska Sea Ice Program offers daily sea ice and sea surface temperature analysis products. The program also delivers a five day sea ice forecast 3 times each week, provides a 3 month sea ice outlook at the end of each month, and has staff available to respond to sea ice related information inquiries. These analysis and forecast products are utilized by many entities around the state of Alaska and nationally for safety of navigation and community strategic planning. The list of current customers stem from academia and research institutions, to local state and federal agencies, to resupply barges, to coastal subsistence hunters, to gold dredgers, to fisheries, to the general public. Due to a longer sea ice free season over recent years, activity in the waters around Alaska has increased. This has led to a rise in decision support services from the Alaska Sea Ice Program. The ASIP is in constant contact with the National Ice Center as well as the United States Coast Guard (USCG) for safety of navigation. In the past, the ASIP provided briefings to the USCG when in support of search and rescue efforts. Currently, not only does that support remain, but our team is also briefing on sea ice outlooks into the next few months. As traffic in the Arctic increases, the ASIP will be called upon to provide more and more services on varying time scales to meet customer needs. This talk will address the many facets of the current Alaska Sea Ice Program as well as delve into what we see as the future of the ASIP.

NWS Alaska Sea Ice Program: Operations, Customer Support & Challenges

NASA Astrophysics Data System (ADS)

Heim, R.; Schreck, M. B.

2016-12-01

The National Weather Service's Alaska Sea Ice Program is designed to service customers and partners operating and planning operations within Alaska waters. The Alaska Sea Ice Program offers daily sea ice and sea surface temperature analysis products. The program also delivers a five day sea ice forecast 3 times each week, provides a 3 month sea ice outlook at the end of each month, and has staff available to respond to sea ice related information inquiries. These analysis and forecast products are utilized by many entities around the state of Alaska and nationally for safety of navigation and community strategic planning. The list of current customers stem from academia and research institutions, to local state and federal agencies, to resupply barges, to coastal subsistence hunters, to gold dredgers, to fisheries, to the general public. Due to a longer sea ice free season over recent years, activity in the waters around Alaska has increased. This has led to a rise in decision support services from the Alaska Sea Ice Program. The ASIP is in constant contact with the National Ice Center as well as the United States Coast Guard (USCG) for safety of navigation. In the past, the ASIP provided briefings to the USCG when in support of search and rescue efforts. Currently, not only does that support remain, but our team is also briefing on sea ice outlooks into the next few months. As traffic in the Arctic increases, the ASIP will be called upon to provide more and more services on varying time scales to meet customer needs. This talk will address the many facets of the current Alaska Sea Ice Program as well as delve into what we see as the future of the ASIP.

Evaluation of Rutter Sigma S6 Ice Navigation Radar on USCGC Healy during Arctic Shield 2014

DTIC Science & Technology

2015-03-01

useful in making decisions about the pressure ridges ahead of time instead of making an immediate decision. Figure 33. CG radar display of... use the radar to help chart an efficient path through an ice field to reduce transit time and fuel expenses. This includes a clear picture of the ice...a ship would be able to use the radar to help chart an efficient path through an ice field to reduce transit time and fuel expenses. This includes

Ice Formation in Frequently Transited Navigation Channels

DTIC Science & Technology

1990-12-01

measurements made at different sec- The propellers were driven by a 186-W electric tions in the monitoring area. The measurements motor, which is visible in...321. Navigation ConferenceandExhibitionattheFinlandia Mellor, M., Vance, G.P., Wuebben, J.C. and G.E. Hall, Helsinki, Finland, p. 1021-103E Frankenstein

Lunar and Lagrangian Point L1 L2 CubeSat Communication and Navigation Considerations

NASA Technical Reports Server (NTRS)

Schaire, Scott; Wong, Yen F.; Altunc, Serhat; Bussey, George; Shelton, Marta; Folta, Dave; Gramling, Cheryl; Celeste, Peter; Anderson, Mile; Perrotto, Trish;

Lewis Research Center earth resources program

NASA Technical Reports Server (NTRS)

Mark, H.

1972-01-01

The Lewis Research Center earth resources program efforts are in the areas of: (1) monitoring and rapid evaluation of water quality; (2) determining ice-type and ice coverage distribution to aid operations in a possible extension of the Great Lakes ice navigation and shipping season; (3) monitoring spread of crop viruses; and (4) extent of damage to strip mined areas as well as success of efforts to rehabilitate such areas for agriculture.

76 FR 67596 - Amendment of Class E Airspace; Spearfish, SD

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-02

... Spearfish, SD, to accommodate new Area Navigation (RNAV) Standard Instrument Approach Procedures at Black... additional controlled airspace at Black Hills Airport--Clyde Ice Field (76 FR 43610) Docket No. FAA-2011-0431... procedures at Black Hills Airport--Clyde Ice Field, Spearfish, SD. This action is necessary for the safety...

14 CFR Appendix B to Part 63 - Flight Navigator Training Course Requirements

Code of Federal Regulations, 2011 CFR

2011-01-01

.... Hazards. Air masses. Front weather. Fog. Thunderstorms. Icing. World weather and climate. Weather maps and... required standards, but the period between inspections shall not exceed 12 months. (j) Change of ownership, name, or location—(1) Change of ownership. Approval of a flight navigator course shall not be continued...

14 CFR Appendix B to Part 63 - Flight Navigator Training Course Requirements

Code of Federal Regulations, 2012 CFR

2012-01-01

.... Hazards. Air masses. Front weather. Fog. Thunderstorms. Icing. World weather and climate. Weather maps and... required standards, but the period between inspections shall not exceed 12 months. (j) Change of ownership, name, or location—(1) Change of ownership. Approval of a flight navigator course shall not be continued...

14 CFR Appendix B to Part 63 - Flight Navigator Training Course Requirements

Code of Federal Regulations, 2014 CFR

2014-01-01

.... Hazards. Air masses. Front weather. Fog. Thunderstorms. Icing. World weather and climate. Weather maps and... required standards, but the period between inspections shall not exceed 12 months. (j) Change of ownership, name, or location—(1) Change of ownership. Approval of a flight navigator course shall not be continued...

14 CFR Appendix B to Part 63 - Flight Navigator Training Course Requirements

Code of Federal Regulations, 2013 CFR

2013-01-01

.... Hazards. Air masses. Front weather. Fog. Thunderstorms. Icing. World weather and climate. Weather maps and... required standards, but the period between inspections shall not exceed 12 months. (j) Change of ownership, name, or location—(1) Change of ownership. Approval of a flight navigator course shall not be continued...

33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

Code of Federal Regulations, 2014 CFR

2014-07-01

... of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A vessel... miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not...

33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

Code of Federal Regulations, 2010 CFR

2010-07-01

... of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A vessel... miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not...

33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

Code of Federal Regulations, 2013 CFR

2013-07-01

... of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A vessel... miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not...

33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

Code of Federal Regulations, 2012 CFR

2012-07-01

... of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A vessel... miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not...

33 CFR 151.79 - Operating requirements: Discharge of sewage within Antarctica.

Code of Federal Regulations, 2011 CFR

2011-07-01

... of sewage within Antarctica. 151.79 Section 151.79 Navigation and Navigable Waters COAST GUARD... Pollution and Sewage § 151.79 Operating requirements: Discharge of sewage within Antarctica. (a) A vessel... miles of Antarctic land or ice shelves; beyond such distance, sewage stored in a holding tank must not...

An Integrative Wave Model for the Marginal Ice Zone based on a Rheological Parameterization

DTIC Science & Technology

2013-09-30

climate in the present and future Arctic seas. OBJECTIVES 1. To build a comprehensive wave-ice interaction mathematical framework for a wide...group (e.g. Fox and Squire, 1994, Meylan and Squire, 1996, Bennetts and Squire, 2009) is also applicable to the case of ice floes imbedded in a frazil...environmental protection purposes: such as navigation route planning, offshore structure design in the Arctic , and coastal erosion prevention. They

The Environmental Evaluation Work Group Fiscal Year 1979 Studies of the Winter Navigation Demonstration Program. Effects of Ship-Induced Waves in an Ice Environment on the St. Marys River Ecosystem

DTIC Science & Technology

1979-07-27

April 17-21, immediately after the solid ice cover had been broken up by heavy vessel traffic. 4. 1acroinvertebrates of 56 taxa were identified in 75...clams), Amphipoda (scuds), Polychaeta, Ephemeroptera (mayflies), and Trichoptera (caddisflies) were common in all samples and collectively made up about...period of solid ice cover. Comparison of drift net catches in March when there was solid ice cover and moderate vessel traffic with catches in April

Field Results for an Arctic AUV Designed for Characterizing Circulation and Ice Thickness

NASA Astrophysics Data System (ADS)

Bellingham, J. G.; Kirkwood, W. J.; Tervalon, N.; Cokelet, E.; Thomas, H.; Sibenac, M.; Gashler, D.; McEwen, R.; Henthorn, R.; Shane, F.; Osborn, D. J.; Johnson, K.; Overland, J.; Stein, P.; Bahlavouni, A.; Anderson, D.

2002-12-01

An Autonomous Underwater Vehicle designed for operation at high latitudes and under ice completed its first Arctic field tests from the USCGC Healy in fall of 2001. The ALTEX AUV has been under development since 1998, and is being created to provide: unprecedented endurance, ability to navigate at high latitudes, a depth rating of 1500 to 4500 meters depending on payload, and the capability to relay data through the ice to satellites via data buoys. The AUV's initial applications are focused on tracking the warm Atlantic Layer inflow - the primary source of seawater to the Arctic Ocean. Consequently the primary payloads are twin pumped CTD systems. Oxygen and nitrate sensors provide the ability to use NO as a tracer. An ice profiling sonar allows the AUV to estimate the ice thickness in real-time and is designed to generate high quality post-processed ice draft data comparable to that collected through the SCICEX program. The experiments in October aboard the USCGC Healy generated numerous water column and under-ice data sets. Traditional ship-based CTD operations were used to provide a comparison data set for AUV water column measurements. The post-processed ice draft results show reasonable ice profiles and have the potential, when combined with other science data collected, to shed some additional light on upper water column processes in ice-covered regions. Cruise results include: operating the AUV from the USCGC Healy in the ice pack, demonstrating inertial navigation system performance, obtaining oceanographic sections with the AUV, obtaining ice draft measurements with an AUV born sonar, and testing the data-buoy system. This work is supported by the National Science Foundation under grant NSF-OPP 9910290. The Packard Foundation and the Office of Naval Research have also provided support. The project was initiated under the National Ocean Partnership Program under contract N00014-98-1-0814.

Proceedings of oceans 87. The ocean - an international workplace

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-01-01

This book includes proceedings containing 347 papers. Some of the topics are: ICE -Cold ocean and ice research; ICE-1-Icebergs; ICE-2-Sea ice and structures; IE-3-Cold ocean instrumentation; ICE-4-Ocean and ice; INS-Oceanographic instrumentation; INS-1-Acoustic Doppler Current profilers; ENG-1-New solutions to old problems; ENG-2-energy from the ocean; ENG-3-Cables and connectors; POL-Policy, education and technology transfer; POL-1-International issues; POL-2-Ocean space utilization; POL-3-Economics, planning and management; SCI-6-fish stock assessment; ACI-7-Coastal currents and sediment; SCI-9-Satellite navigation; SCI-10-Deep sea minerals and methods of recovery; ODS-Fifth working symposium on oceanographic data system; ODS-1-Data base management; UND-Underwater work systems; UND-1-Diving for science.

Determining the ice seasons severity during 1982-2015 using the ice extents sum as a new characteristic

NASA Astrophysics Data System (ADS)

Rjazin, Jevgeni; Pärn, Ove

2016-04-01

Sea ice is a key climate factor and it restricts considerably the winter navigation in sever seasons on the Baltic Sea. So determining ice conditions severity and describing ice cover behaviour at severe seasons interests scientists, engineers and navigation managers. The present study is carried out to determine the ice seasons severity degree basing on the ice seasons 1982 to 2015. A new integrative characteristic is introduced to describe the ice season severity. It is the sum of ice extents of the ice season id est the daily ice extents of the season are summed. The commonly used procedure to determine the ice season severity degree by the maximal ice extent is in this research compared to the new characteristic values. The remote sensing data on the ice concentrations on the Baltic Sea published in the European Copernicus Programme are used to obtain the severity characteristic values. The ice extents are calculated on these ice concentration data. Both the maximal ice extent of the season and a newly introduced characteristic - the ice extents sum are used to classify the winters with respect of severity. The most severe winter of the reviewed period is 1986/87. Also the ice seasons 1981/82, 1984/85, 1985/86, 1995/96 and 2002/03 are classified as severe. Only three seasons of this list are severe by both the criteria. They are 1984/85, 1985/86 and 1986/87. We interpret this coincidence as the evidence of enough-during extensive ice cover in these three seasons. In several winters, for example 2010/11 ice cover extended enough for some time, but did not endure. At few other ice seasons as 2002/03 the Baltic Sea was ice-covered in moderate extent, but the ice cover stayed long time. At 11 winters the ice extents sum differed considerably (> 10%) from the maximal ice extent. These winters yield one third of the studied ice seasons. The maximal ice extent of the season is simple to use and enables to reconstruct the ice cover history and to predict maximal ice extent values. A shortage of this characteristic is its failure to account with the ice cover durability. The ice extents sum enables to describe the ice cover behaviour more adequately. However using this characteristic we lack the option to compare its values with those in the past as the ice cover extent was not daily measured then. We can use ice extents sum only for those ice seasons on which we have enough data. Using the ice extents sum of the season adds the temporal dimension to the ice season severity study.

Statistical Analyses of High-Resolution Aircraft and Satellite Observations of Sea Ice: Applications for Improving Model Simulations

NASA Astrophysics Data System (ADS)

Farrell, S. L.; Kurtz, N. T.; Richter-Menge, J.; Harbeck, J. P.; Onana, V.

2012-12-01

Satellite-derived estimates of ice thickness and observations of ice extent over the last decade point to a downward trend in the basin-scale ice volume of the Arctic Ocean. This loss has broad-ranging impacts on the regional climate and ecosystems, as well as implications for regional infrastructure, marine navigation, national security, and resource exploration. New observational datasets at small spatial and temporal scales are now required to improve our understanding of physical processes occurring within the ice pack and advance parameterizations in the next generation of numerical sea-ice models. High-resolution airborne and satellite observations of the sea ice are now available at meter-scale resolution or better that provide new details on the properties and morphology of the ice pack across basin scales. For example the NASA IceBridge airborne campaign routinely surveys the sea ice of the Arctic and Southern Oceans with an advanced sensor suite including laser and radar altimeters and digital cameras that together provide high-resolution measurements of sea ice freeboard, thickness, snow depth and lead distribution. Here we present statistical analyses of the ice pack primarily derived from the following IceBridge instruments: the Digital Mapping System (DMS), a nadir-looking, high-resolution digital camera; the Airborne Topographic Mapper, a scanning lidar; and the University of Kansas snow radar, a novel instrument designed to estimate snow depth on sea ice. Together these instruments provide data from which a wide range of sea ice properties may be derived. We provide statistics on lead distribution and spacing, lead width and area, floe size and distance between floes, as well as ridge height, frequency and distribution. The goals of this study are to (i) identify unique statistics that can be used to describe the characteristics of specific ice regions, for example first-year/multi-year ice, diffuse ice edge/consolidated ice pack, and convergent/divergent ice zones, (ii) provide datasets that support enhanced parameterizations in numerical models as well as model initialization and validation, (iii) parameters of interest to Arctic stakeholders for marine navigation and ice engineering studies, and (iv) statistics that support algorithm development for the next-generation of airborne and satellite altimeters, including NASA's ICESat-2 mission. We describe the potential contribution our results can make towards the improvement of coupled ice-ocean numerical models, and discuss how data synthesis and integration with high-resolution models may improve our understanding of sea ice variability and our capabilities in predicting the future state of the ice pack.

Medium-range predictability of early summer sea ice thickness distribution in the East Siberian Sea based on the TOPAZ4 ice-ocean data assimilation system

NASA Astrophysics Data System (ADS)

Nakanowatari, Takuya; Inoue, Jun; Sato, Kazutoshi; Bertino, Laurent; Xie, Jiping; Matsueda, Mio; Yamagami, Akio; Sugimura, Takeshi; Yabuki, Hironori; Otsuka, Natsuhiko

2018-06-01

Accelerated retreat of Arctic Ocean summertime sea ice has focused attention on the potential use of the Northern Sea Route (NSR), for which sea ice thickness (SIT) information is crucial for safe maritime navigation. This study evaluated the medium-range (lead time below 10 days) forecast of SIT distribution in the East Siberian Sea (ESS) in early summer (June-July) based on the TOPAZ4 ice-ocean data assimilation system. A comparison of the operational model SIT data with reliable SIT estimates (hindcast, satellite and in situ data) showed that the TOPAZ4 reanalysis qualitatively reproduces the tongue-like distribution of SIT in ESS in early summer and the seasonal variations. Pattern correlation analysis of the SIT forecast data over 3 years (2014-2016) reveals that the early summer SIT distribution is accurately predicted for a lead time of up to 3 days, but that the prediction accuracy drops abruptly after the fourth day, which is related to a dynamical process controlled by synoptic-scale atmospheric fluctuations. For longer lead times ( > 4 days), the thermodynamic melting process takes over, which contributes to most of the remaining prediction accuracy. In July 2014, during which an ice-blocking incident occurred, relatively thick SIT ( ˜ 150 cm) was simulated over the ESS, which is consistent with the reduction in vessel speed. These results suggest that TOPAZ4 sea ice information has great potential for practical applications in summertime maritime navigation via the NSR.

Investigation of air transportation technology at Massachusetts Institute of Technology, 1984

NASA Technical Reports Server (NTRS)

Simpson, Robert W.

1987-01-01

Three projects sponsored by the Joint University Program at MIT are summarized. Two projects were focussed on the potential application of Loran-C in flying nonprecision approaches to general aviation runways, and the third project involved research on aircraft icing. In one Loran-C project, Aircraft Approach Guidance Using Relative Loran-C Navigation, the concept was flight tested. It used the difference in TD's from those of the touchdown point to simplify and speed navigation computer processing and took advantage of the short term accuracy of less than 100 feet for Loran-C. The goal of the project, Probabilistic Modelling of Loran-C Error for Nonprecision Approaches, was to develop a mathematical model which would predict the probability that an approach flown to a runway with a particular Loran-C receiver would fall within a given standard. The Aircraft Icing project focussed on measurement of droplet trajectories and droplet impingement/runback characteristics and measurement of real time ice accretion using ultrasonic pulse echo techniques.

Future sea ice conditions and weather forecasts in the Arctic: Implications for Arctic shipping.

PubMed

Gascard, Jean-Claude; Riemann-Campe, Kathrin; Gerdes, Rüdiger; Schyberg, Harald; Randriamampianina, Roger; Karcher, Michael; Zhang, Jinlun; Rafizadeh, Mehrad

2017-12-01

The ability to forecast sea ice (both extent and thickness) and weather conditions are the major factors when it comes to safe marine transportation in the Arctic Ocean. This paper presents findings focusing on sea ice and weather prediction in the Arctic Ocean for navigation purposes, in particular along the Northeast Passage. Based on comparison with the observed sea ice concentrations for validation, the best performing Earth system models from the Intergovernmental Panel on Climate Change (IPCC) program (CMIP5-Coupled Model Intercomparison Project phase 5) were selected to provide ranges of potential future sea ice conditions. Our results showed that, despite a general tendency toward less sea ice cover in summer, internal variability will still be large and shipping along the Northeast Passage might still be hampered by sea ice blocking narrow passages. This will make sea ice forecasts on shorter time and space scales and Arctic weather prediction even more important.

Sand Waves That Impede Navigation of Coastal Inlet Navigation Channels

DTIC Science & Technology

2006-08-01

Merrymeeting Bay. The bay collects coarse-grained sediment from unconsolidated ice-contact and periglacial deposits (Fenster and FitzGerald 1996). During...bed, which is a layer of denser or larger sized sediment left after finer material has been winnowed by a strong current, can inhibit bed form...Order Descriptors (important) • Superposition: simple or compound. • Sediment Characteristics (size, sorting). Third Order Descriptors (useful

Effects of Ship-Induced Waves in an Ice Environment on the St. Marys River Ecosystem,

DTIC Science & Technology

1980-01-01

Oligochaeta (worms), and Gastropoda (snails) comprised about 67% of the total number of organisms collected. Pelecypoda (fingernail clams), Amphipoda...Identiflero/Open.Endad Terms St. Marys River, winter navigation, Chronomidae, Oligochaetes, Gastropoda , ice c. cosATI ieid/Group IS. Availaleity...Chronomidae (midge larvae), Oligochaeta (worms), and Gastropoda (snails); collectively they comprised about 67% of the total number of organisms

Counting whales in a challenging, changing environment

PubMed Central

Williams, R.; Kelly, N.; Boebel, O.; Friedlaender, A. S.; Herr, H.; Kock, K.-H.; Lehnert, L. S.; Maksym, T.; Roberts, J.; Scheidat, M.; Siebert, U.; Brierley, A. S.

2014-01-01

Estimating abundance of Antarctic minke whales is central to the International Whaling Commission's conservation and management work and understanding impacts of climate change on polar marine ecosystems. Detecting abundance trends is problematic, in part because minke whales are frequently sighted within Antarctic sea ice where navigational safety concerns prevent ships from surveying. Using icebreaker-supported helicopters, we conducted aerial surveys across a gradient of ice conditions to estimate minke whale density in the Weddell Sea. The surveys revealed substantial numbers of whales inside the sea ice. The Antarctic summer sea ice is undergoing rapid regional change in annual extent, distribution, and length of ice-covered season. These trends, along with substantial interannual variability in ice conditions, affect the proportion of whales available to be counted by traditional shipboard surveys. The strong association between whales and the dynamic, changing sea ice requires reexamination of the power to detect trends in whale abundance or predict ecosystem responses to climate change. PMID:24622821

Sea ice and surface water circulation, Alaskan Continental Shelf

NASA Technical Reports Server (NTRS)

Wright, F. F. (Principal Investigator); Sharma, G. D.; Burn, J. J.

1973-01-01

The author has identified the following significant results. The boundaries of land-fast ice, distribution of pack ice, and major polynya were studied in the vicinity of the Bering Strait. Movement of pack ice during 24 hours was determined by plotting the distinctly identifiable ice floes on ERTS-1 imagery obtained from two consecutive passes. Considerably large shallow area along the western Seward Peninsula just north of the Bering Strait is covered by land fast ice. This ice hinders the movement of ice formed in eastern Chukchi Sea southward through the Bering Strait. The movement of ice along the Russian coast is relatively faster. Plotting of some of the ice floes indicated movement of ice in excess of 30 km in and south of the Bering Strait between 6 and 7 March, 1973. North of the Bering Strait the movement approached 18 km. The movement of ice observed during March 6 and 7 considerably altered the distribution and extent of polynya. These features when continually plotted should be of considerable aid in navigation of ice breakers. The movement of ice will also help delineate the migration and distribution of sea mammals.

EnEx-RANGE - Robust autonomous Acoustic Navigation in Glacial icE

NASA Astrophysics Data System (ADS)

Heinen, Dirk; Eliseev, Dmitry; Henke, Christoph; Jeschke, Sabina; Linder, Peter; Reuter, Sebastian; Schönitz, Sebastian; Scholz, Franziska; Weinstock, Lars Steffen; Wickmann, Stefan; Wiebusch, Christopher; Zierke, Simon

2017-03-01

Within the Enceladus Explorer Initiative of the DLR Space Administration navigation technologies for a future space mission are in development. Those technologies are the basis for the search for extraterrestrial life on the Saturn moon Enceladus. An autonomous melting probe, the EnEx probe, aims to extract a liquid sample from a water reservoir below the icy crust. A first EnEx probe was developed and demonstrated in a terrestrial scenario at the Bloodfalls, Taylor Glacier, Antarctica in November 2014. To enable navigation in glacier ice two acoustic systems were integrated into the probe in addition to conventional navigation technologies. The first acoustic system determines the position of the probe during the run based on propagation times of acoustic signals from emitters at reference positions at the glacier surface to receivers in the probe. The second system provides information about the forefield of the probe. It is based on sonographic principles with phased array technology integrated in the probe's melting head. Information about obstacles or sampling regions in the probe's forefield can be acquired. The development of both systems is now continued in the project EnEx-RANGE. The emitters of the localization system are replaced by a network of intelligent acoustic enabled melting probes. These localize each other by means of acoustic signals and create the reference system for the EnEx probe. This presentation includes the discussion of the intelligent acoustic network, the acoustic navigation systems of the EnEx probe and results of terrestrial tests.

Operationally Monitoring Sea Ice at the Canadian Ice Service

NASA Astrophysics Data System (ADS)

de Abreu, R.; Flett, D.; Carrieres, T.; Falkingham, J.

2004-05-01

The Canadian Ice Service (CIS) of the Meteorological Service of Canada promotes safe and efficient maritime operations and protects Canada's environment by providing reliable and timely information about ice and iceberg conditions in Canadian waters. Daily and seasonal charts describing the extent, type and concentration of sea ice and icebergs are provided to support navigation and other activities (e.g. oil and gas) in coastal waters. The CIS relies on a suite of spaceborne visible, infrared and microwave sensors to operationally monitor ice conditions in Canadian coastal and inland waterways. These efforts are complemented by operational sea ice models that are customized and run at the CIS. The archive of these data represent a 35 year archive of ice conditions and have proven to be a valuable dataset for historical sea ice analysis. This presentation will describe the daily integration of remote sensing observations and modelled ice conditions used to produce ice and iceberg products. A review of the decadal evolution of this process will be presented, as well as a glimpse into the future of ice and iceberg monitoring. Examples of the utility of the CIS digital sea ice archive for climate studies will also be presented.

Zero-fluoroscopy cryothermal ablation of atrioventricular nodal re-entry tachycardia guided by endovascular and endocardial catheter visualization using intracardiac echocardiography (Ice&ICE Trial).

PubMed

Luani, Blerim; Zrenner, Bernhard; Basho, Maksim; Genz, Conrad; Rauwolf, Thomas; Tanev, Ivan; Schmeisser, Alexander; Braun-Dullaeus, Rüdiger C

2018-01-01

Stochastic damage of the ionizing radiation to both patients and medical staff is a drawback of fluoroscopic guidance during catheter ablation of cardiac arrhythmias. Therefore, emerging zero-fluoroscopy catheter-guidance techniques are of great interest. We investigated, in a prospective pilot study, the feasibility and safety of the cryothermal (CA) slow-pathway ablation in patients with symptomatic atrioventricular-nodal-re-entry-tachycardia (AVNRT) using solely intracardiac echocardiography (ICE) for endovascular and endocardial catheter visualization. Twenty-five consecutive patients (mean age 55.6 ± 12.0 years, 17 female) with ECG-documentation or symptoms suggesting AVNRT underwent an electrophysiology study (EPS) in our laboratory utilizing ICE for catheter navigation. Supraventricular tachycardia was inducible in 23 (92%) patients; AVNRT was confirmed by appropriate stimulation maneuvers in 20 (80%) patients. All EPS in the AVNRT subgroup could be accomplished without need for fluoroscopy, relying solely on ICE-guidance. CA guided by anatomical location and slow-pathway potentials was successful in all patients, median cryo-mappings = 6 (IQR:3-10), median cryo-ablations = 2 (IQR:1-3). Fluoroscopy was used to facilitate the trans-septal puncture and localization of the ablation substrate in the remaining 3 patients (one focal atrial tachycardia and two atrioventricular-re-entry-tachycardias). Mean EPS duration in the AVNRT subgroup was 99.8 ± 39.6 minutes, ICE guided catheter placement 11.9 ± 5.8 minutes, time needed for diagnostic evaluation 27.1 ± 10.8 minutes, and cryo-application duration 26.3 ± 30.8 minutes. ICE-guided zero-fluoroscopy CA in AVNRT patients is feasible and safe. Real-time visualization of the true endovascular borders and cardiac structures allow for safe catheter navigation during the ICE-guided EPS and might be an alternative to visualization technologies using geometry reconstructions. © 2017 Wiley Periodicals, Inc.

Managing the ice in the waters ahead: lessons from the Titanic.

PubMed

Waymack, Pamela M

2006-07-01

To navigate carefully through today's rough healthcare waters, healthcare financial managers need to: Plan for the unexpected. Realize that technology alone is not a solution. Refrain from being overconfident

First spaceborne phase altimetry over sea ice using TechDemoSat-1 GNSS-R signals

NASA Astrophysics Data System (ADS)

Li, Weiqiang; Cardellach, Estel; Fabra, Fran; Rius, Antonio; Ribó, Serni; Martín-Neira, Manuel

2017-08-01

A track of sea ice reflected Global Navigation Satellite System (GNSS) signal collected by the TechDemoSat-1 mission is processed to perform phase altimetry over sea ice. High-precision carrier phase measurements are extracted from coherent GNSS reflections at a high angle of elevation (>57°). The altimetric results show good consistency with a mean sea surface (MSS) model, and the root-mean-square difference is 4.7 cm with an along-track sampling distance of ˜140 m and a spatial resolution of ˜400 m. The difference observed between the altimetric results and the MSS shows good correlation with the colocated sea ice thickness data from Soil Moisture and Ocean Salinity. This is consistent with the reflecting surface aligned with the bottom of the ice-water interface, due to the penetration of the GNSS signal into the sea ice. Therefore, these high-precision altimetric results have potential to be used for determination of sea ice thickness.

Annual Report Fiscal Year 2003 of the Secretary of the Army on Civil Works Activities (1 October 2004 - 30 September 2005)

DTIC Science & Technology

2006-08-25

the glaciers that covered the Great Lakes region during the last ice age. IMPROVEMENTS Navigation Page 1. Alpena Harbor, MI...21-85 NAVIGATION 1. ALPENA HARBOR, MI Location. At mouth of Thunder Bay River which empties into Thunder Bay, Lake Huron...Harbor is 100 miles southeast of Cheboygan Harbor, MI. River has its source in Montmorency and Alpena Counties, MI. (See NOAA Nautical Chart

Bibliography on Cold Regions Science and Technology. Volume 39, Part 1, 1985,

DTIC Science & Technology

1985-12-01

ad their effect on ship speed . te.394678 Borodsachev, V.E., Dynamics of ice cover. Edited by 349Jskobshsnvna Glacier drainage basis: a balaneaess L.A...39-1856 lee navigation, Ships , lee conditions, Ice loads, Dam- Metzner, R.C., Hanson, A ., Johnson, J.. " s Environmental and performance monitoring...Russian. t1I 39-2594 Logistics, Marine transportation, Cargo . Ships . a refs. Deployment of satellite automatic weather sensing A brief-ree is heno (if the

Estimation of degree of sea ice ridging based on dual-polarized C-band SAR data

NASA Astrophysics Data System (ADS)

Gegiuc, Alexandru; Similä, Markku; Karvonen, Juha; Lensu, Mikko; Mäkynen, Marko; Vainio, Jouni

2018-01-01

For ship navigation in the Baltic Sea ice, parameters such as ice edge, ice concentration, ice thickness and degree of ridging are usually reported daily in manually prepared ice charts. These charts provide icebreakers with essential information for route optimization and fuel calculations. However, manual ice charting requires long analysis times, and detailed analysis of large areas (e.g. Arctic Ocean) is not feasible. Here, we propose a method for automatic estimation of the degree of ice ridging in the Baltic Sea region, based on RADARSAT-2 C-band dual-polarized (HH/HV channels) SAR texture features and sea ice concentration information extracted from Finnish ice charts. The SAR images were first segmented and then several texture features were extracted for each segment. Using the random forest method, we classified them into four classes of ridging intensity and compared them to the reference data extracted from the digitized ice charts. The overall agreement between the ice-chart-based degree of ice ridging and the automated results varied monthly, being 83, 63 and 81 % in January, February and March 2013, respectively. The correspondence between the degree of ice ridging reported in the ice charts and the actual ridge density was validated with data collected during a field campaign in March 2011. In principle the method can be applied to the seasonal sea ice regime in the Arctic Ocean.

Mapping uncharted territory in ice from zeolite networks to ice structures.

PubMed

Engel, Edgar A; Anelli, Andrea; Ceriotti, Michele; Pickard, Chris J; Needs, Richard J

2018-06-05

Ice is one of the most extensively studied condensed matter systems. Yet, both experimentally and theoretically several new phases have been discovered over the last years. Here we report a large-scale density-functional-theory study of the configuration space of water ice. We geometry optimise 74,963 ice structures, which are selected and constructed from over five million tetrahedral networks listed in the databases of Treacy, Deem, and the International Zeolite Association. All prior knowledge of ice is set aside and we introduce "generalised convex hulls" to identify configurations stabilised by appropriate thermodynamic constraints. We thereby rediscover all known phases (I-XVII, i, 0 and the quartz phase) except the metastable ice IV. Crucially, we also find promising candidates for ices XVIII through LI. Using the "sketch-map" dimensionality-reduction algorithm we construct an a priori, navigable map of configuration space, which reproduces similarity relations between structures and highlights the novel candidates. By relating the known phases to the tractably small, yet structurally diverse set of synthesisable candidate structures, we provide an excellent starting point for identifying formation pathways.

Arctic Physical Oceanography.

DTIC Science & Technology

1984-07-01

series of fluActuations. a 1 ate velocity was recorded -’ith bot "h fixed and rofig current meter systems . Current v eters eaere rigidly attached to 750-r...with the U.S. Navy Transit satellite navigation system two per hour. II _20. 00 " 00 Ice slotion - 5i 850 FRAM-I drill frock 0F 1500 Monned floe o...kilometers of such survey line was flown. system . In addition 200 km of continuous aeromagnetic lines Both sea ice and water were sampled for later were

Hydrocarbon biodegradation by Arctic sea-ice and sub-ice microbial communities during microcosm experiments, Northwest Passage (Nunavut, Canada).

PubMed

Garneau, Marie-Ève; Michel, Christine; Meisterhans, Guillaume; Fortin, Nathalie; King, Thomas L; Greer, Charles W; Lee, Kenneth

2016-10-01

The increasing accessibility to navigation and offshore oil exploration brings risks of hydrocarbon releases in Arctic waters. Bioremediation of hydrocarbons is a promising mitigation strategy but challenges remain, particularly due to low microbial metabolic rates in cold, ice-covered seas. Hydrocarbon degradation potential of ice-associated microbes collected from the Northwest Passage was investigated. Microcosm incubations were run for 15 days at -1.7°C with and without oil to determine the effects of hydrocarbon exposure on microbial abundance, diversity and activity, and to estimate component-specific hydrocarbon loss. Diversity was assessed with automated ribosomal intergenic spacer analysis and Ion Torrent 16S rRNA gene sequencing. Bacterial activity was measured by (3)H-leucine uptake rates. After incubation, sub-ice and sea-ice communities degraded 94% and 48% of the initial hydrocarbons, respectively. Hydrocarbon exposure changed the composition of sea-ice and sub-ice communities; in sea-ice microcosms, Bacteroidetes (mainly Polaribacter) dominated whereas in sub-ice microcosms, the contribution of Epsilonproteobacteria increased, and that of Alphaproteobacteria and Bacteroidetes decreased. Sequencing data revealed a decline in diversity and increases in Colwellia and Moritella in oil-treated microcosms. Low concentration of dissolved organic matter (DOM) in sub-ice seawater may explain higher hydrocarbon degradation when compared to sea ice, where DOM was abundant and composed of labile exopolysaccharides. © Fisheries and Oceans Canada [2016].

Integrating expert- and algorithm-derived data to generate a hemispheric ice edge

NASA Astrophysics Data System (ADS)

Tsatsoulis, C.; Komp, E.

The Arctic ice edge is the area of the Arctic where sea ice concentration is less than 15%, and is considered navigable by most vessels. Experts at the National Ice Center generate a daily ice edge product that is available to the public. Data of preference is that of active, high resolution satellite sensors such as RADARSAT which yields all-weather images of 100m resolution, and a second source is OLS data with 550m resolution. Unfortunately, RADARSAT does not provide full, daily coverage of the Arctic and OLS can be obscured by clouds. The SSM/I sensor provides complete coverage of the Arctic at 25km resolution and is independent of cloud cover and solar illumination during the Arctic winter. SSM/I data is analyzed by the NASA Team algorithm to establish ice concentration. Our work integrates the ice edge created by experts using high resolution data with the ice edge generated out of the coarser SSM/I microwave data. The result is a product that combines human and algorithmic outputs, deals with gross differences in resolution of the underlying data sets, and results in a useful, operational product.

Maritime User Requirements at High Latitudes - the MARENOR Project

NASA Astrophysics Data System (ADS)

Behlke, R.

2014-12-01

The ionosphere at high latitudes is characterised by a great variety of spatial and temporal variations that influence radio signals. In addition to navigation solutions that are based on Global Navigation Satellite Systems (GNSS), satellite communication systems also suffer from ionospheric degradation. This is worsened by harsh weather conditions, insufficient coverage by geostationary satellites and the absence of land-based augmentation infrastructure. Climate change will lead to a decrease in sea ice extent and thus to an increased use of trans-polar shipping routes, presence of gas and oil industries in the High Arctic and higher focus on Search-and-Rescue (SAR) as well as sovereignty issues. These moments usually require navigation and communication solutions that are accurate and reliable. We describe requirements presented by industrial operators on and around Svalbard. In addition, we present the MARENOR project that aims on evaluating navigation and communication systems at high latitudes including first results

An Intelligent Pinger Network for Solid Glacier Environments

NASA Astrophysics Data System (ADS)

Schönitz, S.; Reuter, S.; Henke, C.; Jeschke, S.; Ewert, D.; Eliseev, D.; Heinen, D.; Linder, P.; Scholz, F.; Weinstock, L.; Wickmann, S.; Wiebusch, C.; Zierke, S.

2016-12-01

This talk presents a novel approach for an intelligent, agent-based pinger network in an extraterrestrial glacier environment. Because of recent findings of the Cassini spacecraft, a mission to Saturn's moon Enceladus is planned in order search for extraterrestrial life within the ocean beneath Enceladus' ice crust. Therefore, a maneuverable melting probe, the EnEx probe, was developed to melt into Enceladus' ice and take liquid samples from water-filled crevasses. Hence, the probe collecting the samples has to be able to navigate in ice which is a hard problem, because neither visual nor gravitational methods can be used. To enhance the navigability of the probe, a network of autonomous pinger units (APU) is in development that is able to extract a map of the ice environment via ultrasonic soundwaves. A network of these APUs will be deployed on the surface of Enceladus, melt into the ice and form a network to help guide the probe safely to its destination. The APU network is able to form itself fully autonomously and to compensate system failures of individual APUs. The agents controlling the single APU are realized by rule-based expert systems implemented in CLIPS. The rule-based expert system evaluates available information of the environment, decides for actions to take to achieve the desired goal (e.g. a specific network topology), and executes and monitors such actions. In general, it encodes certain situations that are evaluated whenever an APU is currently idle, and then decides for a next action to take. It bases this decision on its internal world model that is shared with the other APUs. The optimal network topology that defines each agents position is iteratively determined by mixed-integer nonlinear programming. Extensive simulations studies show that the proposed agent design enables the APUs to form a robust network topology that is suited to create a reliable 3D map of the ice environment.

Waterway Ice Thickness Measurements

NASA Technical Reports Server (NTRS)

1978-01-01

The ship on the opposite page is a U. S. Steel Corporation tanker cruising through the ice-covered waters of the Great Lakes in the dead of winter. The ship's crew is able to navigate safely by plotting courses through open water or thin ice, a technique made possible by a multi-agency technology demonstration program in which NASA is a leading participant. Traditionally, the Great Lakes-St. Lawrence Seaway System is closed to shipping for more than three months of winter season because of ice blockage, particularly fluctuations in the thickness and location of ice cover due to storms, wind, currents and variable temperatures. Shippers have long sought a system of navigation that would allow year-round operation on the Lakes and produce enormous economic and fuel conservation benefits. Interrupted operations require that industrial firms stockpile materials to carry them through the impassable months, which is costly. Alternatively, they must haul cargos by more expensive overland transportation. Studies estimate the economic benefits of year-round Great Lakes shipping in the hundreds of millions of dollars annually and fuel consumption savings in the tens of millions of gallons. Under Project Icewarn, NASA, the U.S. Coast Guard and the National Oceanic Atmospheric Administration collaborated in development and demonstration of a system that permits safe year-round operations. It employs airborne radars, satellite communications relay and facsimile transmission to provide shippers and ships' masters up-to-date ice charts. Lewis Research Center contributed an accurate methods of measuring ice thickness by means of a special "short-pulse" type of radar. In a three-year demonstration program, Coast Guard aircraft equipped with Side-Looking Airborne Radar (SLAR) flew over the Great Lakes three or four times a week. The SLAR, which can penetrate clouds, provided large area readings of the type and distribution of ice cover. The information was supplemented by short-pulse radar measurements of ice thickness. The radar data was relayed by a NOAA satellite to a ground station where NOAA analyzed it and created picture maps, such as the one shown at lower left, showing where icebreakers can cut paths easily or where shipping can move through thin ice without the aid of icebreakers. The ice charts were then relayed directly to the wheelhouses of ships operating on the Lakes. Following up the success of the Great Lakes program, the icewarn team applied its system in another demonstration, this one a similarly successful application designed to aid Arctic coast shipping along the Alaskan North Slope. Further improvement of the ice-monitoring system is planned. Although aircraft-mounted radar is effective, satellites could provide more frequent data. After the launch this year of Seasat, an ocean-monitoring satellite, NASA will conduct tests to determine the ice-mapping capability and accuracy of satellite radar images.

Sea Ice Detection Based on Differential Delay-Doppler Maps from UK TechDemoSat-1

PubMed Central

Zhu, Yongchao; Yu, Kegen; Zou, Jingui; Wickert, Jens

2017-01-01

Global Navigation Satellite System (GNSS) signals can be exploited to remotely sense atmosphere and land and ocean surface to retrieve a range of geophysical parameters. This paper proposes two new methods, termed as power-summation of differential Delay-Doppler Maps (PS-D) and pixel-number of differential Delay-Doppler Maps (PN-D), to distinguish between sea ice and sea water using differential Delay-Doppler Maps (dDDMs). PS-D and PN-D make use of power-summation and pixel-number of dDDMs, respectively, to measure the degree of difference between two DDMs so as to determine the transition state (water-water, water-ice, ice-ice and ice-water) and hence ice and water are detected. Moreover, an adaptive incoherent averaging of DDMs is employed to improve the computational efficiency. A large number of DDMs recorded by UK TechDemoSat-1 (TDS-1) over the Arctic region are used to test the proposed sea ice detection methods. Through evaluating against ground-truth measurements from the Ocean Sea Ice SAF, the proposed PS-D and PN-D methods achieve a probability of detection of 99.72% and 99.69% respectively, while the probability of false detection is 0.28% and 0.31% respectively. PMID:28704948

Nimbus 6 Random Access Measurement System applications experiments

NASA Technical Reports Server (NTRS)

Cote, C. E. (Editor); Taylor, R. (Editor); Gilbert, E. (Editor)

1982-01-01

The advantages of a technique in which data collection platforms randomly transmit signal to a polar orbiting satellite, thus eliminating satellite interrogation are demonstrated in investigations of the atmosphere; oceanographic parameters; Arctic regions and ice conditions; navigation and position location; and data buoy development.

Sea ice decline and 21st century trans-Arctic shipping routes

NASA Astrophysics Data System (ADS)

Melia, N.; Haines, K.; Hawkins, E.

2016-09-01

The observed decline in Arctic sea ice is projected to continue, opening shorter trade routes across the Arctic Ocean, with potentially global economic implications. Here we quantify, using Coupled Model Intercomparison Project Phase 5 global climate model simulations calibrated to remove spatial biases, how projected sea ice loss might increase opportunities for Arctic transit shipping. By midcentury for standard open water vessels, the frequency of navigable periods doubles, with routes across the central Arctic becoming available. A sea ice-ship speed relationship is used to show that European routes to Asia typically become 10 days faster via the Arctic than alternatives by midcentury, and 13 days faster by late century, while North American routes become 4 days faster. Future greenhouse gas emissions have a larger impact by late century; the shipping season reaching 4-8 months in Representative Concentration Pathway (RCP)8.5 double that of RCP2.6, both with substantial interannual variability. Moderately, ice-strengthened vessels likely enable Arctic transits for 10-12 months by late century.

Maiden Voyage of the Under-Ice Float

NASA Astrophysics Data System (ADS)

Shcherbina, A.; D'Asaro, E. A.; Light, B.; Deming, J. W.; Rehm, E.

2016-02-01

The Under-Ice Float (UIF) is a new autonomous platform for sea ice and upper ocean observations in the marginal ice zone (MIZ). UIF is based on the Mixed Layer Lagrangian Float design, inheriting its accurate buoyancy control and relatively heavy payload capability. A major challenge for sustained autonomous observations in the MIZ is detection of open water for navigation and telemetry surfacings. UIF employs the new surface classification algorithm based on the spectral analysis of surface roughness sensed by an upward-looking sonar. A prototype UIF was deployed in the MIZ of the central Arctic Ocean in late August 2015. The main payload of the first UIF was a bio-optical suit consisting of upward- and downward hyperspectral radiometers; temperature, salinity, chlorophyll, turbidity, and dissolved oxygen sensors, and a high-definition photo camera. In the early stages of its mission, the float successfully avoided ice, detected leads, surfaced in open water, and transmitted data and photographs. We will present the analysis of these observations from the full UIF mission extending into the freeze-up season.

Edwardsiella andrillae, a new species of sea anemone from Antarctic ice.

PubMed

Daly, Marymegan; Rack, Frank; Zook, Robert

2013-01-01

Exploration of the lower surface of the Ross Ice Shelf in Antarctica by the Submersible Capable of under-Ice Navigation and Imaging (SCINI) remotely operated vehicle discovered a new species of sea anemone living in this previously undocumented ecosystem. This discovery was a significant outcome of the Coulman High Project's geophysical and environmental fieldwork in 2010-2011 as part of the ANDRILL (ANtarctic geologic DRILLing) program. Edwardsiella andrillae n. sp., lives with most of its column in the ice shelf, with only the tentacle crown extending into the seawater below. In addition to being the only Antarctic representative of the genus, Edwardsiella andrillae is distinguished from all other species of the genus in the number of tentacles and in the size and distribution of cnidae. The anatomy and histology of Edwardsiella andrillae present no features that explain how this animal withstands the challenges of life in such an unusual habitat.

Edwardsiella andrillae, a New Species of Sea Anemone from Antarctic Ice

PubMed Central

Daly, Marymegan; Rack, Frank; Zook, Robert

2013-01-01

Exploration of the lower surface of the Ross Ice Shelf in Antarctica by the Submersible Capable of under-Ice Navigation and Imaging (SCINI) remotely operated vehicle discovered a new species of sea anemone living in this previously undocumented ecosystem. This discovery was a significant outcome of the Coulman High Project’s geophysical and environmental fieldwork in 2010-2011 as part of the ANDRILL (ANtarctic geologic DRILLing) program. Edwardsiella andrillae n. sp., lives with most of its column in the ice shelf, with only the tentacle crown extending into the seawater below. In addition to being the only Antarctic representative of the genus, Edwardsiella andrillae is distinguished from all other species of the genus in the number of tentacles and in the size and distribution of cnidae. The anatomy and histology of Edwardsiella andrillae present no features that explain how this animal withstands the challenges of life in such an unusual habitat. PMID:24349517

Monitoring of Sea Ice Dynamic by Means of ERS-Envisat Tandem Cross-Interferometry

NASA Astrophysics Data System (ADS)

Pasquali, Paolo; Cantone, Alessio; Barbieri, Massimo; Engdahl, Marcus

2010-03-01

The interest in the monitoring of sea ice masses has increased greatly over the past decades for a variety of reasons. These include:- Navigation in northern latitude waters;- transportation of petroleum;- exploitation of mineral deposits in the Arctic, and- the use of icebergs as a source of fresh water.The availability of ERS-Envisat 28minute tandem acquisitions from dedicated campaigns, covering large areas in the northern latitudes with large geometrical baseline and very short temporal separation, allows the precise estimation of sea ice displacement fields with an accuracy that cannot be obtained on large scale from any other instrument. This article presents different results of sea ice dynamic monitoring over northern Canada obtained within the "ERS-Envisat Tandem Cross-Interferometry Campaigns: CInSAR processing and studies over extended areas" project from data acquired during the 2008-2009 Tandem campaign..

Environmental Predictors of Ice Seal Presence in the Bering Sea

PubMed Central

Miksis-Olds, Jennifer L.

2014-01-01

Ice seals overwintering in the Bering Sea are challenged with foraging, finding mates, and maintaining breathing holes in a dark and ice covered environment. Due to the difficulty of studying these species in their natural environment, very little is known about how the seals navigate under ice. Here we identify specific environmental parameters, including components of the ambient background sound, that are predictive of ice seal presence in the Bering Sea. Multi-year mooring deployments provided synoptic time series of acoustic and oceanographic parameters from which environmental parameters predictive of species presence were identified through a series of mixed models. Ice cover and 10 kHz sound level were significant predictors of seal presence, with 40 kHz sound and prey presence (combined with ice cover) as potential predictors as well. Ice seal presence showed a strong positive correlation with ice cover and a negative association with 10 kHz environmental sound. On average, there was a 20–30 dB difference between sound levels during solid ice conditions compared to open water or melting conditions, providing a salient acoustic gradient between open water and solid ice conditions by which ice seals could orient. By constantly assessing the acoustic environment associated with the seasonal ice movement in the Bering Sea, it is possible that ice seals could utilize aspects of the soundscape to gauge their safe distance to open water or the ice edge by orienting in the direction of higher sound levels indicative of open water, especially in the frequency range above 1 kHz. In rapidly changing Arctic and sub-Arctic environments, the seasonal ice conditions and soundscapes are likely to change which may impact the ability of animals using ice presence and cues to successfully function during the winter breeding season. PMID:25229453

Transit navigation through Northern Sea Route from satellite data and CMIP5 simulations

NASA Astrophysics Data System (ADS)

Khon, Vyacheslav C.; Mokhov, Igor I.; Semenov, Vladimir A.

2017-02-01

Rapid Arctic sea ice decline over the last few decades opens new perspectives for Arctic marine navigation. Further warming in the Arctic will promote the Northern Sea Route (NSR) as an alternative to the conventional Suez or Panama Canal routes for intercontinental shipping. Here we use both satellite data and CMIP5 ensemble of climate models to estimate the NSR transit window allowing intercontinental navigation between Atlantic and Pacific regions. To this end, we introduce a novel approach to calculate start and end dates of the navigation season along the NSR. We show that modern climate models are able to reproduce the mean time of the NSR transit window and its trend over the last few decades. The selected models demonstrate that the rate of increase of the NSR navigation season will slow down over the next few decades with the RCP4.5 scenario. By the end of the 21st century ensemble-mean estimates show an increase of the NSR transit window by about 4 and 6.5 months according to RCP4.5 and 8.5, respectively. Estimated trends for the end date of the navigation season are found to be stronger compared to those for the start date.

Oceanography Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › FNMOC › Oceanography Products FNMOC Logo FNMOC Navigation Meteorology Products Oceanography Products Tropical Applications Climatology and Archived Data Info Oceanography Products Global

Publications about Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Publications about Products USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center

Software - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Software USNO Logo USNO Navigation Earth Orientation Search databases Auxiliary Software Supporting Software Form Folder Earth Orientation Matrix Calculator

USNO Scientific Colloquia - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You Navigation Tour Information USNO Scientific Colloquia Info USNO Scientific Colloquia Time and Place: Unless departure. Add additional time prior to arriving at the colloquium for issuance of a visitors badge and

NASA-ISRO synthetic aperture radar (NISAR) for temporal tracking of iceberg calving events in the Antarctica

NASA Astrophysics Data System (ADS)

Jawak, S. D.; Luis, A. J.

2017-12-01

Estimating mass loss of the Antarctic ice sheet caused by iceberg calving is a challenging job. Antarctica is surrounded by a variety of large, medium and small sized ice shelves, glacier tongues and coastal areas without offshore floating ice masses. It is possible to monitor surface structures on the continental ice and the ice shelves as well as calved icebergs using NASA-ISRO synthetic aperture radar (NISAR) satellite images in future. The NISAR, which is planned to be launched in 2020, can be used as an all-weather and all-season system to classify the coastline of Antarctica to map patterns of surface structures close to the calving front. Additionally, classifying patterns and density of surface structures distributed over the ice shelves and ice tongues can be a challenging research where NISAR can be of a great advantage. So this work explores use of NISAR to map surface structures visible on ice shelves which can provide advisories to field teams. The ice shelf fronts has been categorized into various classes based on surface structures relative to the calving front within a 30 km-wide seaward strip. The resulting map of the classified calving fronts around Antarctica and their description would provide a detailed representation of crevasse formation and dominant iceberg in the southern ocean which pose a threat to navigation of Antarctic bound ships.

Impacts of Colville River dynamics on river navigability near Nuiqsut, Alaska: 1955-present

NASA Astrophysics Data System (ADS)

Whitley, M. A.; Panda, S. K.; Prakash, A.; Brinkman, T. J.

2016-12-01

Climate-driven changes in river systems are challenging access to ecosystem services such as access to traditional hunting grounds and other subsistence food sources on the North Slope of Alaska. This work studies the dynamics of the Colville River and assesses the impacts on traditional harvest practices and subsistence travel of the Native community of Nuiqsut. Recent reports from Nuiqsut residents indicate accelerated changes in the environment, limiting river travel and their ability to harvest subsistence food. This study explores how channel migration, gravel bars, and bank erosion have evolved since the 1950s, and their impact on water depth and navigability. In an area of ice-rich permafrost, warmer summer temperatures exacerbate lateral bank erosion, resulting in river siltation. The study focuses on selected key areas south of Nuiqsut that have shown significant change in river geomorphology. Since 1955, some areas proximate to ice wedge exposures show channel migration in excess of 1 km. Panchromatic aerial photography acquired by US Geological Surveys in the mid 1950s, color infrared aerial photography from 1979 and 1982 acquired by the Alaska High Altitude Photography (AHAP) mission, and high resolution satellite images from Digital Globe, Inc. were used in this study. We mapped water, vegetation, and gravel/non-vegetated classes to identify risk areas for river navigability. River bathymetry was also mapped using a multispectral ratio-based water depth retrieval algorithm to identify problem sites for boat travel. Remote sensing products and analyses were validated with field data for mapping risk areas along the river. This study has the potential to be implemented on a larger scale for predictive mapping to aid river navigation. Findings from this study will provide insight whether recent changes are anomalies, or if they are part of a directional trend that will require local adaptation.

Leap Second Announcement - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › Leap Second Announcement USNO Logo USNO Navigation Earth Orientation Products GPS-based Products VLBI-based Products EO Information Center Publications

Earth Orientation - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation USNO Logo USNO Navigation Earth Orientation Products GPS -based Products VLBI-based Products EO Information Center Publications about Products Software Info Earth

Gulf of Mexico Imagery - Satellite Products and Services Division/Office of

Science.gov Websites

Satellite and Product Operations Skip Navigation Link NESDIS banner image and link to NESDIS Home Page Default Office of Satellite and Product Operations banner image and link to OSPO DOC / NOAA Bleaching -- Ocean Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface Temperatures -- Tropical

Southwest U.S. Imagery (GOES-WEST) - Satellite Services Division / Office

Science.gov Websites

of Satellite Data Processing and Distribution Skip Navigation Link NESDIS banner image and link Information Service Home Page Default Office of Satellite and Product Operations banner image and link to OSPO Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface Temperatures -- Tropical Systems Product List

Tropical Pacific Imagery - Satellite Products and Services Division/Office

Science.gov Websites

of Satellite and Product Operations Skip Navigation Link NESDIS banner image and link to NESDIS Home Page Default Office of Satellite and Product Operations banner image and link to OSPO DOC / NOAA Bleaching -- Ocean Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface Temperatures -- Tropical

Tropical West Pacific Imagery - Satellite Products and Services

Science.gov Websites

Division/Office of Satellite and Product Operations Skip Navigation Link NESDIS banner image Information Service Home Page Default Office of Satellite and Product Operations banner image and link to OSPO MIRS MSPPS Ocean -- Coral Bleaching -- Ocean Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface

Tropical Atlantic Imagery - Satellite Products and Services Division/Office

Science.gov Websites

of Satellite and Product Operations Skip Navigation Link NESDIS banner image and link to NESDIS Home Page Default Office of Satellite and Product Operations banner image and link to OSPO DOC / NOAA Bleaching -- Ocean Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface Temperatures -- Tropical

First results from a new interdisciplinary robotic vehicle for under-ice research

NASA Astrophysics Data System (ADS)

Nicolaus, M.; Katlein, C.; Schiller, M.

2016-12-01

Research at the ice-water interface below drifting sea-ice is crucial for the investigation of the fluxes of energy, momentum and matter across the atmosphere-ice-ocean boundary. Transmission of solar energy through the ice and snow layers causes warming of the upper ocean and melting of the ice itself. It is also a key factor for in and under-ice primary production, supplying the ice associated food-chain and causing carbon export to deeper water layers and the sea floor. The complex geometry of sea ice does not only cause a large spatial variability in optical properties of the ice cover, but also influences biomass accumulations and especially the hydrodynamic interaction between the ice cover and the uppermost layers of the ocean. Access to the ice underside is however still sparse, as diving operations are risky and logistically challenging. In the last decade, robotic underwater technologies have evolved significantly and enabled the first targeted large-scale observations by remotely operated and autonomous underwater vehicles. A new remotely operated vehicle was commissioned for under ice research at the Alfred Wegener Institute supported by the FRAM infrastructure program of the Helmholtz-Society. Apart from proven under-ice navigation and operation capabilities, the vehicle provides an extended interdisciplinary sensor platform supporting oceanographic, biological, biogeochemical and physical sea-ice research. Here we present the first preliminary data obtained with the new vehicle during the PS101 expedition of the German icebreaker RV Polarstern to the Central Arctic in September and October 2016. Apart from measurements of spectral light transmittance of sea ice during the autumn freeze-up, we show vertical profiles of the bio-optical and oceanographic properties of the upper water column. This data is combined with under-ice topography obtained from upward-looking multibeam sonar, still imagery and HD-video material.

Evaluation of the operational SAR based Baltic sea ice concentration products

NASA Astrophysics Data System (ADS)

Karvonen, Juha

Sea ice concentration is an important ice parameter both for weather and climate modeling and sea ice navigation. We have developed an fully automated algorithm for sea ice concentration retrieval using dual-polarized ScanSAR wide mode RADARSAT-2 data. RADARSAT-2 is a C-band SAR instrument enabling dual-polarized acquisition in ScanSAR mode. The swath width for the RADARSAT-2 ScanSAR mode is about 500 km, making it very suitable for operational sea ice monitoring. The polarization combination used in our concentration estimation is HH/HV. The SAR data is first preprocessed, the preprocessing consists of geo-rectification to Mercator projection, incidence angle correction fro both the polarization channels. and SAR mosaicking. After preprocessing a segmentation is performed for the SAR mosaics, and some single-channel and dual-channel features are computed for each SAR segment. Finally the SAR concentration is estimated based on these segment-wise features. The algorithm is similar as introduced in Karvonen 2014. The ice concentration is computed daily using a daily RADARSAT-2 SAR mosaic as its input, and it thus gives the concentration estimated at each Baltic Sea location based on the most recent SAR data at the location. The algorithm has been run in an operational test mode since January 2014. We present evaluation of the SAR-based concentration estimates for the Baltic ice season 2014 by comparing the SAR results with gridded the Finnish Ice Service ice charts and ice concentration estimates from a radiometer algorithm (AMSR-2 Bootstrap algorithm results). References: J. Karvonen, Baltic Sea Ice Concentration Estimation Based on C-Band Dual-Polarized SAR Data, IEEE Transactions on Geoscience and Remote Sensing, in press, DOI: 10.1109/TGRS.2013.2290331, 2014.

The High-Stakes Literacies of Undocumented, Unaccompanied Immigrant Youth Detained in America

ERIC Educational Resources Information Center

Cullerton, Alexis

2013-01-01

Every year, thousands of undocumented, unaccompanied immigrant youth take dangerous journeys to the United States only to be apprehended by Immigration and Customs Enforcement (ICE) upon arrival. These youth, who are both involuntary and voluntary immigrants, are then faced with the challenge of having to navigate the complex contexts of the legal…

Deterioration and Repair of Concrete in the Lower Monumental Navigation Lock Wall.

DTIC Science & Technology

1981-06-01

Lewiston , ID, along the Columbia and Snake Rivers. Because there are no alternate waterways or lock, the transportation system stops if the lock is...tem 3 Page 1 of 1 LOWER SNAKE RIVER PROJECT LOWERGRANITE 7.0 Lewiston LFliLE GOOSE C LOWER ~ MONUMENTAL ~rDN LCOWER SNAKE Tri-cites ICE HAROBO R ASH

VLBI-based Products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Earth Orientation › VLBI-based Products USNO Logo USNO Navigation Earth determine Earth Orientation Parameters (EOP) is Very Long Baseline Interferometry (VLBI). USNO provides both

USNO Master Clock - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Master Clock USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info USNO Master Clock clock vault The USNO Master Clock is the

GPS timing products - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › GPS USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info GPS timing products USNO monitors the GPS constellation and provides

Precise Time - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Precise Time The U. S. Naval Observatory is charged with maintaining the

Two-way Satellite Time Transfer - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › TWSTT USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT What is TWSTT? Operational Services Calibration Services Precision Telephone Time NTP Info

GOES Composite - El Niño Support Imagery - Satellite Products and Services

Science.gov Websites

Division/Office of Satellite and Product Operations Skip Navigation Link NESDIS banner image Information Service Home Page Default Office of Satellite and Product Operations banner image and link to OSPO MIRS MSPPS Ocean -- Coral Bleaching -- Ocean Color -- Sea/Lake Ice -- Sea Surface Height -- Sea Surface

Integrating Research on Global Climate Change and Human Use of the Oceans: a Geospatial Method for Daily Monitoring of Sea Ice and Ship Traffic in the Arctic

NASA Astrophysics Data System (ADS)

Eucker, W.; McGillivary, P. A.

2012-12-01

One apparent consequence of global climate change has been a decrease in the extent and thickness of Arctic sea ice more rapidly than models have predicted, while Arctic ship traffic has likewise increased beyond economic predictions. To ensure representative observations of changing climate conditions and human use of the Arctic Ocean, we concluded a method of tracking daily changes in both sea ice and shipping in the Arctic Ocean was needed. Such a process improves the availability of sea ice data for navigational safety and allows future developments to be monitored for understanding of ice and shipping in relation to policy decisions appropriate to optimize sustainable use of a changing Arctic Ocean. The impetus for this work was the 2009 Arctic Marine Shipping Assessment (AMSA) which provided baseline data on Arctic ship traffic. AMSA was based on responses from circumpolar countries, was manpower intensive, and took years to compile. A more timely method of monitoring human use of the Arctic Ocean was needed. To address this, a method of monitoring sea ice on a scale relevant to ship-navigation (<10km) was developed and implemented in conjunction with arctic ship tracking using S-AIS (Satellite Automatic Identification Systems). S-AIS is internationally required on ships over a certain size, which includes most commercial vessels in the Arctic Ocean. Daily AIS and sea ice observations were chosen for this study. Results of this method of geospatial analysis of the entire arctic are presented for a year long period from April 1, 2010 to March 31, 2011. This confirmed the dominance of European Arctic ship traffic. Arctic shipping is maximal during August and diminishes in September with a minimum in winter, although some shipping continues year-round in perennially ice-free areas. Data are analyzed for the four principal arctic quadrants around the North Pole by season for number and nationality of vessels. The goal of this study was not merely to monitor ship traffic and ice conditions concurrently, but also to demonstrate a new method of ocean monitoring based on daily assimilation, data fusion, and integrated visualization of satellite ice remote sensing data and S-AIS ship data. In the future, as Arctic ship traffic and cryosphere sea ice cover variability are both expected to increase, this method can provide near real-time physical data on global climate change and human dimensions of ocean use of to guide policies addressing arctic resource management, Search and Rescue (SAR) operations, oil spill response, and issues such as ship noise impacts on marine mammals, and whale-ship collision avoidance. An internationally agreed implementation of this methodology would benefit ships operating in the Arctic and advance sustainable use of the Arctic Ocean.

Comparing the Behavior of Polarimetric SAR Imagery (TerraSAR-X and Radarsat-2) for Automated Sea Ice Classification

NASA Astrophysics Data System (ADS)

Ressel, Rudolf; Singha, Suman; Lehner, Susanne

2016-08-01

Arctic Sea ice monitoring has attracted increasing attention over the last few decades. Besides the scientific interest in sea ice, the operational aspect of ice charting is becoming more important due to growing navigational possibilities in an increasingly ice free Arctic. For this purpose, satellite borne SAR imagery has become an invaluable tool. In past, mostly single polarimetric datasets were investigated with supervised or unsupervised classification schemes for sea ice investigation. Despite proven sea ice classification achievements on single polarimetric data, a fully automatic, general purpose classifier for single-pol data has not been established due to large variation of sea ice manifestations and incidence angle impact. Recently, through the advent of polarimetric SAR sensors, polarimetric features have moved into the focus of ice classification research. The higher information content four polarimetric channels promises to offer greater insight into sea ice scattering mechanism and overcome some of the shortcomings of single- polarimetric classifiers. Two spatially and temporally coincident pairs of fully polarimetric acquisitions from the TerraSAR-X/TanDEM-X and RADARSAT-2 satellites are investigated. Proposed supervised classification algorithm consists of two steps: The first step comprises a feature extraction, the results of which are ingested into a neural network classifier in the second step. Based on the common coherency and covariance matrix, we extract a number of features and analyze the relevance and redundancy by means of mutual information for the purpose of sea ice classification. Coherency matrix based features which require an eigendecomposition are found to be either of low relevance or redundant to other covariance matrix based features. Among the most useful features for classification are matrix invariant based features (Geometric Intensity, Scattering Diversity, Surface Scattering Fraction).

Fragmentation and melting of the seasonal sea ice cover

NASA Astrophysics Data System (ADS)

Feltham, D. L.; Bateson, A.; Schroeder, D.; Ridley, J. K.; Aksenov, Y.

2017-12-01

Recent years have seen a rapid reduction in the summer extent of Arctic sea ice. This trend has implications for navigation, oil exploration, wildlife, and local communities. Furthermore the Arctic sea ice cover impacts the exchange of heat and momentum between the ocean and atmosphere with significant teleconnections across the climate system, particularly mid to low latitudes in the Northern Hemisphere. The treatment of melting and break-up processes of the seasonal sea ice cover within climate models is currently limited. In particular floes are assumed to have a uniform size which does not evolve with time. Observations suggest however that floe sizes can be modelled as truncated power law distributions, with different exponents for smaller and larger floes. This study aims to examine factors controlling the floe size distribution in the seasonal and marginal ice zone. This includes lateral melting, wave induced break-up of floes, and the feedback between floe size and the mixed ocean layer. These results are then used to quantify the proximate mechanisms of seasonal sea ice reduction in a sea ice—ocean mixed layer model. Observations are used to assess and calibrate the model. The impacts of introducing these processes to the model will be discussed and the preliminary results of sensitivity and feedback studies will also be presented.

33 CFR 207.718 - Navigation locks and approach channels, Columbia and Snake Rivers, Oreg. and Wash.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Ice Harbor, WUJ 43 Lower Monumental, WUJ 44 Little Goose, or WUJ 45 Lower Granite, at least one-half... is 19 feet. When the river flow at Lower Granite exceeds 330,000 cubic feet per second the normal... Lower Granite Lock and Dam. The waters restricted to all vessels, except Government vessels, are...

33 CFR 207.718 - Navigation locks and approach channels, Columbia and Snake Rivers, Oreg. and Wash.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Ice Harbor, WUJ 43 Lower Monumental, WUJ 44 Little Goose, or WUJ 45 Lower Granite, at least one-half... is 19 feet. When the river flow at Lower Granite exceeds 330,000 cubic feet per second the normal... Lower Granite Lock and Dam. The waters restricted to all vessels, except Government vessels, are...

33 CFR 207.718 - Navigation locks and approach channels, Columbia and Snake Rivers, Oreg. and Wash.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Ice Harbor, WUJ 43 Lower Monumental, WUJ 44 Little Goose, or WUJ 45 Lower Granite, at least one-half... is 19 feet. When the river flow at Lower Granite exceeds 330,000 cubic feet per second the normal... Lower Granite Lock and Dam. The waters restricted to all vessels, except Government vessels, are...

33 CFR 207.718 - Navigation locks and approach channels, Columbia and Snake Rivers, Oreg. and Wash.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Ice Harbor, WUJ 43 Lower Monumental, WUJ 44 Little Goose, or WUJ 45 Lower Granite, at least one-half... is 19 feet. When the river flow at Lower Granite exceeds 330,000 cubic feet per second the normal... Lower Granite Lock and Dam. The waters restricted to all vessels, except Government vessels, are...

33 CFR 207.718 - Navigation locks and approach channels, Columbia and Snake Rivers, Oreg. and Wash.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Ice Harbor, WUJ 43 Lower Monumental, WUJ 44 Little Goose, or WUJ 45 Lower Granite, at least one-half... is 19 feet. When the river flow at Lower Granite exceeds 330,000 cubic feet per second the normal... Lower Granite Lock and Dam. The waters restricted to all vessels, except Government vessels, are...

14 CFR Special Federal Aviation... - Mitsubishi MU-2B Series Special Training, Experience, and Operating Requirements

Code of Federal Regulations, 2010 CFR

2010-01-01

.... Fuselage 2. Wing 3. Empennage 4. Doors 5. Windshield and Windows C. Airplane Systems 1. Electrical Power 2... System 1. Navigation Lights 2. Anti-Collision Lights 3. Wing Inspection Lights 4. Taxi Lights 5. Landing... Operations 3. Synchronization 4. De-Ice D. Ground Checks 1. Overspeed Governor 2. SRL and Delta P/P 3. NTS...

14 CFR Special Federal Aviation... - Mitsubishi MU-2B Series Special Training, Experience, and Operating Requirements

Code of Federal Regulations, 2011 CFR

2011-01-01

.... Fuselage 2. Wing 3. Empennage 4. Doors 5. Windshield and Windows C. Airplane Systems 1. Electrical Power 2... System 1. Navigation Lights 2. Anti-Collision Lights 3. Wing Inspection Lights 4. Taxi Lights 5. Landing... Operations 3. Synchronization 4. De-Ice D. Ground Checks 1. Overspeed Governor 2. SRL and Delta P/P 3. NTS...

Telephone Time - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Telephone Time USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Telephone Time USNO provides both voice announcements of the

Web-Based Time Synchronization - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › Display Clocks USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Info Web-Based Time Synchronization Web time displays from the

Network Time Protocol - Naval Oceanography Portal

Science.gov Websites

section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home › USNO › Precise Time › NTP USNO Logo USNO Navigation Master Clock GPS Display Clocks TWSTT Telephone Time NTP Eastern TZ Mountain TZ DoD Customers Info Network Time Protocol Network

Multiscale Observation System for Sea Ice Drift and Deformation

NASA Astrophysics Data System (ADS)

Lensu, M.; Haapala, J. J.; Heiler, I.; Karvonen, J.; Suominen, M.

2011-12-01

The drift and deformation of sea ice cover is most commonly followed from successive SAR images. The time interval between the images is seldom less than one day which provides rather crude approximation of the motion fields as ice can move tens of kilometers per day. This is particulary so from the viewpoint of operative services, seeking to provide real time information for ice navigating ships and other end users, as leads are closed and opened or ridge fields created in time scales of one hour or less. The ice forecast models are in a need of better temporal resolution for ice motion data as well. We present experiences from a multiscale monitoring system set up to the Bay of Bothnia, the northernmost basin of the Baltic Sea. The basin generates difficult ice conditions every winter while the ports are kept open with the help of an icebreaker fleet. The key addition to SAR imagery is the use of coastal radars for the monitoring of coastal ice fields. An independent server is used to tap the radar signal and process it to suit ice monitoring purposes. This is done without interfering the basic use of the radars, the ship traffic monitoring. About 20 images per minute are captured and sent to the headquarters for motion field extraction, website animation and distribution. This provides very detailed real time picture of the ice movement and deformation within 20 km range. The real time movements are followed in addition with ice drifter arrays, and using AIS ship identification data, from which the translation of ship cannels due to ice drift can be found out. To the operative setup is associated an extensive research effort that uses the data for ice drift model enhancement. The Baltic ice models seek to forecast conditions relevant to ship traffic, especilly hazardous ones like severe ice compression. The main missing link here is downscaling, or the relation of local scale ice dynamics and kinematics to the ice model scale behaviour. The data flow when combined with SAR images gives information on how large scale ice cover motions manifest as local scale deformations. The research includes also ice stress measurements for relating the kinematic state and modeled stresses to local scale ice cover stresses, and ice thickness mappings with profiling sonars and EM methods. Downscaling results based on four-month campaing during winter 2011 are presented.

ICE navigation support

NASA Astrophysics Data System (ADS)

Efron, L.; Muellerschoen, R. J.; Premkumar, R. I.

1986-08-01

The International Cometary Explorer (ICE) encounter with Comet Giacobini-Zinner took place 7 years after the spacecraft's original launch on 12 August 1978 as the International Sun Earth Explorer 3 (ISEE-3), part of a three-spacecraft project to study the interaction between the solar wind and the Earth's magnetosphere. Transfer to an interplanetary trajectory was performed via a 119-km-altitute, gravity-assist, lunar swingby on December 1983. Navigation support during interplanetary cruise and comet encounter was provided by orbit determination utilizing radio metric data from the DSN 64-meter antennas in Goldstone, California and Madrid, Spain. Orbit solutions yielding predictions of 50-km geocentric delivery accuracy in the target aim plane were achieved during interplanetary cruise and at comet encounter using 6-to-12-week data arcs between periodic attitude-change maneuvers. One-sigma two-way range and range rate residuals were consistently 40 meters and 0.2 mm/s or better, respectively. Non-gravitational forces affected the comet's motion during late August and early September 1985 and caused a 2300-km shift in the orbit of the comet relative to the spacecraft. This necessitated a final ICE orbit trim maneuver 3 days prior to encounter. Near-real-time assessment of two-way 2-GHz (S-band) Doppler pseudo-residuals during the June and July 1985 trajectory change maneuvers aided in calibration of the spacecraft's thrusters in preparation for this final critical maneuver. Post-flight analysis indicates tail centerline passage was achieved within 10 seconds of the predicted time and geocentric position uncertainty at encounter was less than 40 km.

NAVO MSRC Navigator. Fall 2001

DTIC Science & Technology

2001-01-01

of the CAVE. A view from the VR Juggler simulator . The particles indicate snow (white) & ice (blue). Rainfall is shown on the terrain, and clouds as...the Cover: Virtual environment built by the NAVO MSRC Visualization Center for the Concurrent Computing Laboratory for Materials Simulation at...Louisiana State University. This application allows the researchers to visualize a million atom simulation of an indentor puncturing a block of gallium

Polar Applications of Spaceborne Scatterometers.

PubMed

Long, David G

2017-05-01

Wind scatterometers were originally developed for observation of near-surface winds over the ocean. They retrieve wind indirectly by measuring the normalized radar cross section ( σ o ) of the surface, and estimating the wind via a geophysical model function relating σ o to the vector wind. The σ o measurements have proven to be remarkably capable in studies of the polar regions where they can map snow cover; detect the freeze/thaw state of forest, tundra, and ice; map and classify sea ice; and track icebergs. Further, a long time series of scatterometer σ o observations is available to support climate studies. In addition to fundamental scientific research, scatterometer data are operationally used for sea-ice mapping to support navigation. Scatterometers are, thus, invaluable tools for monitoring the polar regions. In this paper, a brief review of some of the polar applications of spaceborne wind scatterometer data is provided. The paper considers both C-band and Ku-band scatterometers, and the relative merits of fan-beam and pencil-beam scatterometers in polar remote sensing are discussed.

Polar Applications of Spaceborne Scatterometers

PubMed Central

Long, David G.

2017-01-01

Wind scatterometers were originally developed for observation of near-surface winds over the ocean. They retrieve wind indirectly by measuring the normalized radar cross section (σo) of the surface, and estimating the wind via a geophysical model function relating σo to the vector wind. The σo measurements have proven to be remarkably capable in studies of the polar regions where they can map snow cover; detect the freeze/thaw state of forest, tundra, and ice; map and classify sea ice; and track icebergs. Further, a long time series of scatterometer σo observations is available to support climate studies. In addition to fundamental scientific research, scatterometer data are operationally used for sea-ice mapping to support navigation. Scatterometers are, thus, invaluable tools for monitoring the polar regions. In this paper, a brief review of some of the polar applications of spaceborne wind scatterometer data is provided. The paper considers both C-band and Ku-band scatterometers, and the relative merits of fan-beam and pencil-beam scatterometers in polar remote sensing are discussed. PMID:28919936

Seeing from Space: What Icebergs Can Tell Us About Ice-ocean Interactions

NASA Astrophysics Data System (ADS)

Scheick, J.; Enderlin, E. M.; Hamilton, G. S.

2017-12-01

Icebergs are an important component of the ice-ocean system, yet until recently they have remained the focus of relatively few studies. Icebergs are an important distributed freshwater and nutrient source and can pose significant hazards for navigation and infrastructure, warranting further study. Importantly, icebergs are also easily observable en masse using satellite imagery and other remote sensing platforms, allowing for the collection of large datasets from already existing archives. Here we present some of the many ways that remotely sensed icebergs can be used to inform our understanding of ice-ocean interactions, as well as some of the limitations of these methods and what information is still needed. We will explore the size and spatial distribution of icebergs through time and what that can tell us about the calving behavior of the parent glacier and/or ocean-driven melting below the waterline. We will also explore the use of icebergs as depth finders and drifters to infer bathymetry and components of fjord circulation, respectively.

ROSS: The Remotely-Operated Surface Sampler - A MediumEndurance, Precision-Navigated Platform Optimized for Uncontaminated Measurement of Upper-Ocean Velocity, Density and Turbulence

DTIC Science & Technology

2015-09-30

ocean  surface.   It  is ideal for studying fronts, river plumes, near-­‐surface  phenomena like ice-­‐ melt  or rain   puddles,  air...regions  too  dangerous  for manned craft (like near glacier faces),  and for interpreting  the  undersea structure  of satellite

Modeling Primary Productivity in the Margin Ice Zone from Glider-Based Measurements of Chlorophyll and Light during the 2014 Miz Program

NASA Astrophysics Data System (ADS)

Perry, M. J.; Lee, C.; Rainville, L.; Cetinic, I.; Yang, E. J.; Kang, S. H.

2016-02-01

In late summer 2014 during the Marginal Ice Zone (MIZ) Experiment, an international project sponsored by ONR, four Seagliders transited open water, through the marginal ice zone, and under ice-covered regions in the Beaufort Sea, penetrating as far as 100 km into the ice pack. The gliders navigated either by GPS in open water or, when under the ice, by acoustics from sound sources embedded in the MIZ autonomous observing array. The glider sensor suite included temperature, temperature microstructure, salinity, oxygen, chlorophyll fluorescence, optical backscatter, and multi-spectral downwelling irradiance. Cruises on the IBRV Araon operating in the open Beaufort Sea and on the R/V Ukpik and Norseman operating in continental shelf waters off Alaska's north slope allowed us to construct proxy libraries for converting chlorophyll fluorescence to chlorophyll concentration and optical backscatter to particulate organic carbon concentration. Water samples were collected for chlorophyll and particulate organic carbon analysis on the cruises and aligned with optical profiles of fluorescence and backscatter using sensors that were factory calibrated at the same time as the glider sensors. Fields of chlorophyll, particulate organic carbon, light, and primary productivity are constructed from the glider data. Productivity is modeled as a function of chlorophyll and light, using photosynthesis-light (PE) models with available PE parameters from Arctic measurements. During August the region under the ice was characterized by a deep chlorophyll maximum layer with low rates of production in overlying waters. A phytoplankton bloom developed in open water at the end of September, preceding the rapid reformation of ice, despite shorter days and reduce irradiation.

Skating mechanics of change-of-direction manoeuvres in ice hockey players.

PubMed

Fortier, Antoine; Turcotte, René A; Pearsall, David J

2014-11-01

Ice hockey requires rapid transitions between skating trajectories to effectively navigate about the ice surface. Player performance relates in large part to effective change-of-direction manoeuvres, but little is known about how those skills are performed mechanically and the effect of equipment design on them. The purpose of this study was to observe the kinetics involved in those manoeuvres as well as to compare whether kinetic differences may result between two skate models of varying ankle mobility. Eight subjects with competitive ice hockey playing experience performed rapid lateral (90°) left and right change-of-direction manoeuvres. Kinetic data were collected using force strain gauge transducers on the blade holders of the skates. Significantly greater forces were applied by the outside skate (50-70% body weight, %BW) in comparison to the inside skate (12-24%BW, p < 0.05). Skate model and turn direction had no main effect, though significant mixed interactions between leg side (inside/outside) with skate model or turn direction (p < 0.05) were observed, with a trend for left-turn dominance. This study demonstrates the asymmetric dynamic behaviour inherent in skating change-of-direction tasks.

Navigating under sea ice promotes rapid maturation of diving physiology and performance in beluga whales.

PubMed

Noren, Shawn R; Suydam, Robert

2016-09-15

Little is known about the postnatal development of the physiological characteristics that support breath-hold in cetaceans, despite their need to swim and dive at birth. Arctic species have the additional demand of avoiding entrapment while navigating under sea ice, where breathing holes are patchily distributed and ephemeral. This is the first investigation of the ontogeny of the biochemistry of the locomotor muscle in a year-round Arctic-dwelling cetacean (beluga whale, Delphinapterus leucas). Compared with what we know about other cetaceans, belugas are born with high myoglobin content (1.56±0.02 g 100 g -1 wet muscle mass, N=2) that matures rapidly. Myoglobin increased by 452% during the first year after birth and achieved adult levels (6.91±0.35 g 100 g -1 wet muscle mass, N=9) by 14 months postpartum. Buffering capacity was 48.88±0.69 slykes (N=2) at birth; adult levels (84.31±1.38 slykes, N=9) were also achieved by 14 months postpartum. As the oxygen stores matured, calculated aerobic dive limit more than doubled over the first year of life, undoubtedly facilitating the movements of calves under sea ice. Nonetheless, small body size theoretically continues to constrain the diving ability of newly weaned 2 year olds, as they only had 74% and 69% of the aerobic breath-hold capacity of larger adult female and male counterparts. These assessments enhance our knowledge of the biology of cetaceans and provide insight into age-specific flexibility to alter underwater behaviors, as may be required with the ongoing alterations in the Arctic marine ecosystem associated with climate change and increased anthropogenic activities. © 2016. Published by The Company of Biologists Ltd.

Advances in river ice hydrology 1999-2003

NASA Astrophysics Data System (ADS)

Morse, Brian; Hicks, Faye

2005-01-01

In the period 1999 to 2003, river ice has continued to have important socio-economic impacts in Canada and other Nordic countries. Concurrently, there have been many important advances in all areas of Canadian research into river ice engineering and hydrology. For example: (1) River ice processes were highlighted in two special journal issues (Canadian Journal of Civil Engineering in 2003 and Hydrological Processes in 2002) and at five conferences (Canadian Committee on River Ice Processes and the Environment in 1999, 2001 and 2003, and International Association of Hydraulic Research in 2000 and 2002). (2) A number of workers have clearly advanced our understanding of river ice processes by bringing together disparate information in comprehensive review articles. (3) There have been significant advances in river ice modelling. For example, both one-dimensional (e.g. RIVICE, RIVJAM, ICEJAM, HEC-RAS, etc.) and two-dimensional (2-D; www.river2d.ca) public-domain ice-jam models are now available. Work is ongoing to improve RIVER2D, and a commercial 2-D ice-process model is being developed. (4) The 1999-2003 period is notable for the number of distinctly hydrological and ecological studies. On the quantitative side, many are making efforts to determine streamflow during the winter period. On the ecological side, some new publications have addressed the link to water quality (temperature, dissolved oxygen, nutrients and pollutants), and others have dealt with sediment transport and geomorphology (particularly as it relates to break-up), stream ecology (plants, food cycle, etc.) and fish habitat.There is the growing recognition, that these types of study require collaborative efforts. In our view, the main areas requiring further work are: (1) to interface geomorphological and habitat models with quantitative river ice hydrodynamic models; (2) to develop a manager's toolbox (database management, remote sensing, forecasting, intervention methodologies, etc.) to enable agencies to intervene better at the time of ice-jam-induced floods; and (3) finalize ice-jam prevention methods on the St Lawrence River to safeguard its $2 billion commercial navigation industry. Copyright

SIPEX 2012: Extreme sea-ice and atmospheric conditions off East Antarctica

NASA Astrophysics Data System (ADS)

Heil, P.; Stammerjohn, S.; Reid, P.; Massom, R. A.; Hutchings, J. K.

2016-09-01

In 2012, Antarctic sea-ice coverage was marked by weak annual-mean climate anomalies that consisted of opposing anomalies early and late in the year (some setting new records) which were interspersed by near-average conditions for most of the austral autumn and winter. Here, we investigate the ocean-ice-atmosphere system off East Antarctica, prior to and during the Sea Ice Physics and Ecosystems eXperiment [SIPEX] 2012, by exploring relationships between atmospheric and oceanic forcing together with the sea-ice and snow characteristics. During August and September 2012, just prior to SIPEX 2012, atmospheric circulation over the Southern Ocean was near-average, setting up the ocean-ice-atmosphere system for near-average conditions. However, below-average surface pressure and temperature as well as strengthened circumpolar winds prevailed during June and July 2012. This led to a new record (19.48×106 km2) in maximum Antarctic sea-ice extent recorded in late September. In contrast to the weak circum-Antarctic conditions, the East Antarctic sector (including the SIPEX 2012 region) experienced positive sea-ice extent and concentration anomalies during most of 2012, coincident with negative atmospheric pressure and sea-surface temperature anomalies. Heavily deformed sea ice appeared to be associated with intensified wind stress due to increased cyclonicity as well as an increased influx of sea ice from the east. This increased westward ice flux is likely linked to the break-up of nearly 80% of the Mertz Glacier Tongue in 2010, which strongly modified the coastal configuration and hence the width of the westward coastal current. Combined with favourable atmospheric conditions the associated changed coastal configuration allowed more sea ice to remain within the coastal current at the expense of a reduced northward flow in the region around 141°-145°E. In addition a westward propagating positive anomaly of sea-ice extent from the western Ross Sea during austral winter 2012 has been identified to have fed into the westward current of the SIPEX 2012 region. A pair of large grounded icebergs appears to have modified the local stress state as well as the structure of the ice pack upstream and also towards the Dalton Glacier Tongue. Together with the increased influx of sea ice into the regions, this contributed to the difficulties in navigating the SIPEX 2012 region.

Middle Range Sea Ice Prediction System of Voyage Environmental Information System in Arctic Sea Route

NASA Astrophysics Data System (ADS)

Lim, H. S.

2017-12-01

Due to global warming, the sea ice in the Arctic Ocean is melting dramatically in summer, which is providing a new opportunity to exploit the Northern Sea Route (NSR) connecting Asia and Europe ship route. Recent increases in logistics transportation through NSR and resource development reveal the possible threats of marine pollution and marine transportation accidents without real-time navigation system. To develop a safe Voyage Environmental Information System (VEIS) for vessels operating, the Korea Institute of Ocean Science and Technology (KIOST) which is supported by the Ministry of Oceans and Fisheries, Korea has initiated the development of short-term and middle range prediction system for the sea ice concentration (SIC) and sea ice thickness (SIT) in NSR since 2014. The sea ice prediction system of VEIS consists of AMSR2 satellite composite images (a day), short-term (a week) prediction system, and middle range (a month) prediction system using a statistical method with re-analysis data (TOPAZ) and short-term predicted model data. In this study, the middle range prediction system for the SIC and SIT in NSR is calibrated with another middle range predicted atmospheric and oceanic data (NOAA CFSv2). The system predicts one month SIC and SIT on a daily basis, as validated with dynamic composite SIC data extracted from AMSR2 L2 satellite images.

Changing Sea Ice Conditions in the Northwest Passage

NASA Astrophysics Data System (ADS)

Tivy, A. C.; Howell, S.; Agnew, T.; Derksen, C.

2010-12-01

The Northwest Passage lies in the middle of Canadian Arctic Archipelago providing a potential deepwater route that links the Atlantic and Pacific Oceans. Discovered by Sir Robert M’Clure in the 1850s, ever-present multi-year ice (MYI) has always prevented its practical navigation. 2007 marked extreme low MYI conditions in the Arctic and temporarily cleared the Northwest Passage. However, is one single clearing event within the Northwest Passage over the past 40 years indicative of future clearings? This analysis addressed two inter-related questions: i) why has the Northwest Passage contained historically heavy amounts of MYI? and ii) will decreases in MYI within the Northwest Passage continue into the future? Results indicate that for nearly 4 decades, the southern regions of the Canadian Arctic Archipelago have continuously operated as a drain-trap for MYI and this mechanism is responsible for maintaining the heavy MYI conditions within the Northwest Passage. The oldest and thickest MYI in the world resides along the northern flank of the Canadian Arctic Archipelago therefore, as the transition to a sea ice-free Arctic continues, MYI from this region will continue to migrate southward to the channels of the Northwest Passage. Results also find that 2007 was indeed an anomalously light sea ice year in the Northwest Passage but record low ice conditions have since been observed as of mid-August 2010.

China and the Arctic: An Opportunity for the U.S.

DTIC Science & Technology

2017-04-06

DISTRIBUTION A. Approved for public release: distribution unlimited. 10 nations’ sovereign claims and the Law of the Sea.53 As an observer on the Arctic...distribution unlimited. 13 China and UNCLOS To sustain or grow its economy, China needs to navigate the Law of the Sea (UNCLOS) concerning the Arctic...right to adopt and enforce non-discriminatory laws and regulations for the prevention, reduction and control of marine pollution from vessels in ice

Field observations of slush ice generated during freeze-up in arctic coastal waters

USGS Publications Warehouse

Reimnitz, E.; Kempema, E.W.

1987-01-01

In some years, large volumes of slush ice charged with sediment are generated from frazil crystals in the shallow Beaufort Sea during strong storms at the time of freeze-up. Such events terminate the navigation season, and because of accompanying hostile conditions, little is known about the processes acting. The water-saturated slush ice, which may reach a thickness of 4 m, exists for only a few days before freezing from the surface downward arrests further wave motion or pancake ice forms. Movements of small vessels and divers in the slush ice occurs only in phase with passing waves, producing compression and rarefaction, and internal pressure pulses. Where in contact with the seafloor, the agitated slush ice moves cobble-size material, generates large sediment ripples, and may possibly produce a flat rampart observed on the arctic shoreface in some years. Processes charging the slush ice with as much as 1000 m3 km-2 of sediment remain uncertain, but our field observations rule out previously proposed filtration from turbid waters as a likely mechanism. Sedimentary particles apparently are only trapped in the interstices of the slush ice rather than being held by adhesion, since wave-related internal pressure oscillations result in downward particle movement and cleansing of the slush ice. This loss of sediment explains the typical downward increase in sediment concentration in that part of the fast-ice canopy composed largely of frazil ice. The congealing slush ice in coastal water does not become fast ice until grounded ridges are formed in the stamukhi zone, one to two months after freeze-up begins. During this period of new-ice mobility, long-range sediment transport occurs. The sediment load held by the fast-ice canopy in the area between the Colville and Sagavanirktok River deltas in the winter of 1978-1979 was 16 times larger than the yearly river input to the same area. This sediment most likely was rafted from Canada, more than 400 km to the east, during a brief time period in the previous fall. Ocean turbulence is greatly reduced while the congealing slush ice drifts about. Therefore, new ice then forming in intervening open-water areas is clean. These events explain the patchy appearance of the fast ice after the summer snowmelt. More work on the important phenomena reported here is needed to close a major gap in the knowledge of the arctic marine environment. ?? 1987.

Ice erosion of a sea-floor knickpoint at the inner edge of the stamukhi zone, Beaufort Sea, Alaska

USGS Publications Warehouse

Barnes, P.W.; Asbury, J.L.; Rearic, D.M.; Ross, C.R.

1987-01-01

In 1981 and 1982, detailed bathymetric and side-scan sonar surveys were made of an area of the sea floor north of Prudhoe Bay, Alaska, to study the changing characteristics of the seabed at the inner boundary of the stamukhi zone, the coast-parallel zone of grounded ice ridges that occurs in water depths between 15 and 50 m in the arctic. The fathograms and sonographs resolved 10-cm features and electronic navigation gave relocations accurate to about 10 m. Year after year an ice boundary develops at the inner edge of the stamukhi zone where major shear and pressure deformation occur in about the same location. Associated with this ice boundary, the bathymetry shows a pronounced break in slope - the knickpoint - on the shelf profile at about 20 m depth. The 2-3 m-high knickpoint is cut in a consolidated gravelly mud of pre-Holocene age. A well-defined gravel and cobble shoal a few meters high usually occurs at the inshore edge of the knickpoint. The sonograph mosaic shows that seaward of the knickpoint, ice gouges saturate the sea floor and are well defined; inshore the gouges are fewer in number and are poorly defined on the records. Few gouges can be traced from the seaward side of the knickpoint across the shoals to the inshore side of the knickpoint. Studies of ice gouging rates in two seabed corridors that cross the stamukhi zone reveal the highest rates of gouging seaward of the knickpoint. We believe that the knickpoint results from ice erosion at the inner boundary of the stamukhi zone. Intensified currents associated with this boundary winnow away fine sediments. Ice bulldozing and currents shape the shoals, which perch atop the knickpoint. The knickpoint helps to limit ice forces on the seabed inshore of the stamukhi zone. ?? 1987.

Clean Sampling of an Englacial Conduit at Blood Falls, Antarctica - Some Experimental and Numerical Results

NASA Astrophysics Data System (ADS)

Kowalski, Julia; Francke, Gero; Feldmann, Marco; Espe, Clemens; Heinen, Dirk; Digel, Ilya; Clemens, Joachim; Schüller, Kai; Mikucki, Jill; Tulaczyk, Slawek M.; Pettit, Erin; Berry Lyons, W.; Dachwald, Bernd

2017-04-01

There is significant interest in sampling subglacial environments for geochemical and microbiological studies, yet those environments are typically difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. With the "IceMole", a minimally invasive, maneuverable subsurface ice probe, we have developed a clean glacial exploration technology for in-situ analysis and sampling of glacial ice and sub- and englacial materials. Its design is based on combining melting and mechanical stabilization, using an ice screw at the tip of the melting head to maintain firm contact between the melting head and the ice. The IceMole can change its melting direction by differential heating of the melting head and optional side wall heaters. Downward, horizontal and upward melting, as well as curve driving and penetration of particulate-ladden layers has already been demonstrated in several field tests. This maneuverability of the IceMole also necessitates a sophisticated on-board navigation system, capable of autonomous operations. Therefore, between 2012 and 2014, a more advanced probe was developed as part of the "Enceladus Explorer" (EnEx) project. The EnEx-IceMole offers systems for accurate positioning, based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection, which is all integrated through a high-level sensor fusion algorithm. In December 2014, the EnEx-IceMole was used for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, where an englacial brine sample was successfully obtained after about 17 meters of oblique melting. Particular attention was paid to clean protocols for sampling for geochemical and microbiological analysis. In this contribution, we will describe the general technological approach of the IceMole and report on the results of its deployment at Blood Falls. In contrast to conventional melting-probe applications, which can only melt vertically, the IceMole realized an oblique melting path to penetrate the englacial conduit. Experimental and numerical results on melting at oblique angles are rare. Besides reporting on the IceMole technology and the field deployment itself, we will compare and discuss the observed melting behavior with re-analysis results in the context of a recently developed numerical model. Finally, we will present our first steps in utilizing the model to infer on the ambient cryo-environment.

Sea Ice Pressure Ridge Height Distributions for the Arctic Ocean in Winter, Just Prior to Melt

NASA Astrophysics Data System (ADS)

Duncan, K.; Farrell, S. L.; Richter-Menge, J.; Hutchings, J.; Dominguez, R.; Connor, L. N.

2016-12-01

Pressure ridges are one of the most dominant morphological features of the Arctic sea ice pack. An impediment to navigation, pressure ridges are also of climatological interest since they impact the mass, energy and momentum transfer budgets for the Arctic Ocean. Understanding the regional and seasonal distributions of ridge sail heights, and their variability, is important for quantifying total sea ice mass, and for improved treatment of sea ice dynamics in high-resolution numerical models. Observations of sail heights from airborne and ship-based platforms have been documented in previous studies, however studies with both high spatial and temporal resolution, across multiple regions of the Arctic, are only recently possible with the advent of dedicated airborne surveys of the Arctic Ocean. In this study we present results from the high-resolution Digital Mapping System (DMS), flown as part of NASA's Operation IceBridge missions. We use DMS imagery to calculate ridge sail heights, derived from the shadows they cast combined with the solar elevation angle and the known pixel size of each image. Our analyses describe sea ice conditions at the end of winter, during the months of March and April, over a period spanning seven years, from 2010 to 2016. The high spatial resolution (0.1m) and temporal extent (seven years) of the DMS data set provides, for the first time, the full sail-height distributions of both first-year and multi-year sea ice. We present the inter-annual variability in sail height distributions for both the Central Arctic and the Beaufort and Chukchi Seas. We validate our results via comparison with spatially coincident high-resolution SAR imagery and airborne laser altimeter elevations.

Winter Fish Populations in Probable Locations of Air Bubblers in the St. Marys River-Lake Superior Area

DTIC Science & Technology

1980-09-01

Lawrence Seaway Navigation Season Extension, Draft Main Report and Environmental Statement. Detroit, Michigan. Potential effects on fish were discussed...to keep channels ice free for winter vessel passage. The stucies were Jone to determine base line ecological conditions and the effects of the...Subjects were: "Ecological effects of air bub- blers in the winter, a partially annotated bibliography" and "Annotated bibliography on winter fish and

Using Airborne Lidar Data from IcePod to Measure Annual and Seasonal Ice Changes Over Greenland

NASA Astrophysics Data System (ADS)

Frearson, N.; Bertinato, C.; Das, I.

2014-12-01

The IcePod is a multi-sensor airborne science platform that supports a wide suite of instruments, including a Riegl VQ-580 infrared scanning laser, GPS-inertial positioning system, shallow and deep-ice radars, visible-wave and infrared cameras, and upward-looking pyrometer. These instruments allow us to image the ice from top to bottom, including the surface of melt-water plumes that originate at the ice-ocean boundary. In collaboration with the New York Air National Guard 109th Airlift Wing, the IcePod is flown on LC-130 aircraft, which presents the unique opportunity to routinely image the Greenland ice sheet several times within a season. This is particularly important for mass balance studies, as we can measure elevation changes during the melt season. During the 2014 summer, laser data was collected via IcePod over the Greenland ice sheet, including Russell Glacier, Jakobshavn Glacier, Eqip Glacier, and Summit Camp. The Icepod will also be routinely operated in Antarctica. We present the initial testing, calibration, and error estimates from the first set of laser data that were collected on IcePod. At a survey altitude of 1000 m, the laser swath covers ~ 1000 m. A Northrop-Grumman LN-200 tactical grade IMU is rigidly attached to the laser scanner to provide attitude data at a rate of 200 Hz. Several methods were used to determine the lever arm between the IMU center of navigation and GPS antenna phase center, terrestrial scanning laser, total station survey, and optimal estimation. Additionally, initial bore sight calibration flights yielded misalignment angles within an accuracy of ±4 cm. We also performed routine passes over the airport ramp in Kangerlussuaq, Greenland, comparing the airborne GPS and Lidar data to a reference GPS-based ground survey across the ramp, spot GPS points on the ramp and a nearby GPS base station. Positioning errors can severely impact the accuracy of a laser altimeter when flying over remote regions such as across the ice sheets. Setting up GPS base stations along the flight track can prove to be logistically challenging. We have processed the GPS-inertial data using both DGPS and PPP and present the comparison of those results here. Finally, we discuss our processing, calibration and error estimation methods and compare our results to previously flown IceBridge lines.

Water Ice Clouds as Seen from the Mars Exploration Rovers

NASA Astrophysics Data System (ADS)

Wolff, M. J.; Clancy, R. T.; Banfield, D.; Cuozzo, K.

2005-12-01

Water ice clouds that bear a striking resemblance to terrestrial cirrus (e.g., "Mare's tails") have been observed by the Panoramic Camera (Pancam), the Navigation Camera (Navcam), the Hazard Camera (Hazcam), and the Minature Thermal Emission Spectrometer (Mini-TES) on board the Mars Exploration Rovers (MER). Such phenomena represent an opportunity to characterize local and regional scale meteorology as well as our understanding of the processes involved. However, a necessary first-step is to adequately describe some basic properties of the detected clouds: 1) when are the clouds present (i.e., local time, season, etc.)? 2) where are the clouds present? That is to say, what is the relative frequency between the two rover sites as well as the connection to detections from orbiting spacecraft. 3) what are the observed morphologies? 4) what are the projected velocities (i.e., wind speeds and directions) associated with the clouds? 5) what is the abundance of water ice nuclei (i.e., optical depth)? Our talk will summarize our progress in answering the above questions, as well as provide initial results in connecting the observations to more global behavior in the Martian climate.

Sustaining observations in the polar oceans

PubMed Central

Abrahamsen, E. P.

2014-01-01

Polar oceans present a unique set of challenges to sustained observations. Sea ice cover restricts navigation for ships and autonomous measurement platforms alike, and icebergs present a hazard to instruments deployed in the upper ocean and in shelf seas. However, the important role of the poles in the global ocean circulation provides ample justification for sustained observations in these regions, both to monitor the rapid changes taking place, and to better understand climate processes in these traditionally poorly sampled areas. In the past, the vast majority of polar measurements took place in the summer. In recent years, novel techniques such as miniature CTD (conductivity–temperature–depth) tags carried by seals have provided an explosion in year-round measurements in areas largely inaccessible to ships, and, as ice avoidance is added to autonomous profiling floats and gliders, these promise to provide further enhancements to observing systems. In addition, remote sensing provides vital information about changes taking place in sea ice cover at both poles. To make these observations sustainable into the future, improved international coordination and collaboration is necessary to gain optimum utilization of observing networks. PMID:25157189

Applications of ERTS-1 imagery to terrestrial and marine environmental analyses in Alaska

NASA Technical Reports Server (NTRS)

Anderson, D. M.; Mckim, H. L.; Crowder, W. K.; Haugen, R. K.; Gatto, L. W.; Marlar, T. L.

1974-01-01

ERTS-1 imagery provides a means of distinguishing and monitoring estuarine surface water circulation patterns and changes in the relative sediment load of discharging rivers on a regional basis. It also will aid local fishing industries by augmenting currently available hydrologic and navigation charts. The interpretation of geologic and vegetation features resulted in preparation of improved surficial geology, vegetation and permafrost terrain maps at a scale of 1:1 million utilizing ERTS-1 band 7 imagery. This information will be further utilized in a route and site selection study for the Nome to Kobuk Road in central Alaska. Large river icings along the proposed Alaska pipeline route have been monitored. Sea ice deformation and drift northeast of Point Barrow, Alaska has been measured and shorefast ice accumulation and ablation along the west coast of Alaska is being mapped for the spring and early summer seasons. These data will be used for route and site selection, regional environmental analysis, identification and inventory of natural resources, land use planning, and in land use regulation and management.

A lander mission to probe subglacial water on Saturn's moon Enceladus for life

NASA Astrophysics Data System (ADS)

Konstantinidis, Konstantinos; Flores Martinez, Claudio L.; Dachwald, Bernd; Ohndorf, Andreas; Dykta, Paul; Bowitz, Pascal; Rudolph, Martin; Digel, Ilya; Kowalski, Julia; Voigt, Konstantin; Förstner, Roger

2015-01-01

The plumes discovered by the Cassini mission emanating from the south pole of Saturn's moon Enceladus and the unique chemistry found in them have fueled speculations that Enceladus may harbor life. The presumed aquiferous fractures from which the plumes emanate would make a prime target in the search for extraterrestrial life and would be more easily accessible than the moon's subglacial ocean. A lander mission that is equipped with a subsurface maneuverable ice melting probe will be most suitable to assess the existence of life on Enceladus. A lander would have to land at a safe distance away from a plume source and melt its way to the inner wall of the fracture to analyze the plume subsurface liquids before potential biosignatures are degraded or destroyed by exposure to the vacuum of space. A possible approach for the in situ detection of biosignatures in such samples can be based on the hypothesis of universal evolutionary convergence, meaning that the independent and repeated emergence of life and certain adaptive traits is wide-spread throughout the cosmos. We thus present a hypothetical evolutionary trajectory leading towards the emergence of methanogenic chemoautotrophic microorganisms as the baseline for putative biological complexity on Enceladus. To detect their presence, several instruments are proposed that may be taken aboard a future subglacial melting probe. The "Enceladus Explorer" (EnEx) project funded by the German Space Administration (DLR), aims to develop a terrestrial navigation system for a subglacial research probe and eventually test it under realistic conditions in Antarctica using the EnEx-IceMole, a novel maneuverable subsurface ice melting probe for clean sampling and in situ analysis of ice and subglacial liquids. As part of the EnEx project, an initial concept study is foreseen for a lander mission to Enceladus to deploy the IceMole near one of the active water plumes on the moon's South-Polar Terrain, where it will search for signatures of life. The general mission concept is to place the Lander at a safe distance from an active plume. The IceMole would then be deployed to melt its way through the ice crust to an aquiferous fracture at a depth of 100 m or more for an in situ examination for the presence of microorganisms. The driving requirement for the mission is the high energy demand by the IceMole to melt through the cold Enceladan ices. This requirement is met by a nuclear reactor providing 5 kW of electrical power. The nuclear reactor and the IceMole are placed on a pallet lander platform. An Orbiter element is also foreseen, with the main function of acting as a communications relay between Lander and Earth. After launch, the Lander and Orbiter will perform the interplanetary transfer to Saturn together, using the on-board nuclear reactor to power electric thrusters. After Saturn orbit insertion, the Combined Spacecraft will continue using Nuclear Electric Propulsion to reach the orbit of Enceladus. After orbit insertion at Enceladus, the Orbiter will perform a detailed reconnaissance of the South-Polar Terrain. At the end of the reconnaissance phase, the Lander will separate from the Orbiter and an autonomously guided landing sequence will place it near one of the active vapor plumes. Once landed, the IceMole will be deployed and start melting through the ice, while navigating around hazards and towards a target subglacial aquiferous fracture. An initial estimation of the mission's cost is given, as well as recommendations on the further development of enabling technologies. The planetary protection challenges posed by such a mission are also addressed.

New space technology advances knowledge of the remote polar regions. [Arctic and Antarctic regions

NASA Technical Reports Server (NTRS)

Macdonald, W. R.

1974-01-01

The application of ERTS-1 imagery is rapidly increasing man's knowledge of polar regions. Products compiled from this imagery at scales of 1:250,000, 1:500,000 and 1:1,000,000 are already providing valuable information to earth scientists working in Antarctica. Significant finds detected by these bench mark products were glaciological changes, advancement in ice fronts, discovery of new geographic features, and the repositioning of nunataks, islands, and ice tongues. Tests conducted in Antarctica have proven the feasibility of tracking Navy navigation satellites to establish ground control for positioning ERTS-1 imagery in remote areas. ERTS imagery coupled with satellite geodesy shows great promise and may prove to be the most practical and cost effective way to meet the small-scale cartographic requirements of the polar science community.

Development and Antarctic Testing of a Maneuverable Probe for Clean In-Situ Analysis and Sampling of Subsurface Ice and Subglacial Aquatic Ecosystems

NASA Astrophysics Data System (ADS)

Francke, G.; Dachwald, B.; Kowalski, J.; Digel, I.; Tulaczyk, S. M.; Mikucki, J.; Feldmann, M.; Espe, C.; Schöngarth, S.; Hiecker, S.; Blandfort, D.; Schüller, K.; Plescher, E.

2016-12-01

There is significant interest in sampling subglacial environments for geochemical and microbiological studies, but those environments are difficult to access. Such environments exist not only on Earth but are also expected beneath the icy crusts of some outer solar system bodies, like the Jovian moon Europa and the Saturnian moon Enceladus. Existing ice drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The "IceMole" is a maneuverable subsurface ice probe for clean in-situ analysis and sampling of glacial ice and subglacial materials. The design is based on combining melting and mechanical propulsion, using an ice screw at the tip of the melting head to maintain firm contact between the melting head and the ice. It can change melting direction by differential heating of the melting head and optional side wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland, where they demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. Hence, the IceMole allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. Therefore, between 2012 and 2014, a more advanced probe was developed as part of the "Enceladus Explorer" (EnEx) project. The EnEx-IceMole offers systems for relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection, which is all integrated through a high-level sensor fusion. In December 2014, it was used for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, where a subglacial brine sample was successfully obtained after about 17 meters of oblique melting. Particular attention was paid to clean protocols for the sampling of subglacial materials for geochemical and microbiological analysis. Much more development has to be done in many areas, however, until the probe can be used for extraterrestrial applications.

Accounts from 19th-century Canadian Arctic explorers' logs reflect present climate conditions

NASA Astrophysics Data System (ADS)

Overland, James E.; Wood, Kevin

The widely perceived failure of 19th-century expeditions to find and transit the Northwest Passage in the Canadian Arctic is often attributed to extraordinary cold climatic conditions associated with the “Little Ice Age” evident in proxy records. However, examination of 44 explorers' logs for the western Arctic from 1818 to 1910 reveals that climate indicators such as navigability, the distribution and thickness of annual sea ice, monthly surface air temperature, and the onset of melt and freeze were within the present range of variability.The quest for the Northwest Passage through the Canadian archipelago during the 19th century is frequently seen as a vain and tragic failure. Polar exploration during the Victorian era seems to us today to have been a costly exercise in heroic futility, which in many respects it was. This perspective has been reinforced since the 1970s, when paleoclimate reconstructions based on Arctic ice core stratigraphy appeared to confirm the existence of exceptionally cold conditions consistent with the period glaciologists had termed the “Little Ice Age” (Figure 1a), with temperatures more than one standard deviation colder relative to an early 20th-century mean [Koerner, 1977; Koerner and Fisher, 1990; Overpeck et al., 1998]. In recent years, the view of the Little Ice Age as a synchronous worldwide and prolonged cold epoch that ended with modern warming has been questioned [Bradley and Jones, 1993; Jones and Briffa, 2001 ;Ogilvie, 2001].

The impact of the CartoSound® image directly acquired from the left atrium for integration in atrial fibrillation ablation.

PubMed

Kaseno, Kenichi; Hisazaki, Kaori; Nakamura, Kohki; Ikeda, Etsuko; Hasegawa, Kanae; Aoyama, Daisetsu; Shiomi, Yuichiro; Ikeda, Hiroyuki; Morishita, Tetsuji; Ishida, Kentaro; Amaya, Naoki; Uzui, Hiroyasu; Tada, Hiroshi

2018-04-14

Intracardiac echocardiographic (ICE) imaging might be useful for integrating three-dimensional computed tomographic (CT) images for left atrial (LA) catheter navigation during atrial fibrillation (AF) ablation. However, the optimal CT image integration method using ICE has not been established. This study included 52 AF patients who underwent successful circumferential pulmonary vein isolation (CPVI). In all patients, CT image integration was performed after the CPVI with the following two methods: (1) using ICE images of the LA derived from the right atrium and right ventricular outflow tract (RA-merge) and (2) using ICE images of the LA directly derived from the LA added to the image for the RA-merge (LA-merge). The accuracy of these two methods was assessed by the distances between the integrated CT image and ICE image (ICE-to-CT distance), and between the CT image and actual ablated sites for the CPVI (CT-to-ABL distance). The mean ICE-to-CT distance was comparable between the two methods (RA-merge = 1.6 ± 0.5 mm, LA-merge = 1.7 ± 0.4 mm; p = 0.33). However, the mean CT-to-ABL distance was shorter for the LA-merge (2.1 ± 0.6 mm) than RA-merge (2.5 ± 0.8 mm; p < 0.01). The LA, especially the left-sided PVs and LA roof, was more sharply delineated by direct LA imaging, and whereas the greatest CT-to-ABL distance was observed at the roof portion of the left superior PV (3.7 ± 2.8 mm) after the RA-merge, it improved to 2.6 ± 1.9 mm after the LA-merge (p < 0.01). Additional ICE images of the LA directly acquired from the LA might lead to a greater accuracy of the CT image integration for the CVPI.

VHF downline communication system for SLAR data

NASA Technical Reports Server (NTRS)

Schertler, R. J.; Chase, T. L.; Mueller, R. A.; Kramarchuk, I.; Jirberg, R. J.; Gedney, R. T.

1979-01-01

A real time VHF downlink communication system is described for transmitting side-looking airborne radar (SLAR) data directly from an aircraft to a portable ground/shipboard receiving station. Use of this receiving station aboard the U.S. Coast Guard icebreaker Mackinaw for generating real-time photographic quality radar images is discussed. The system was developed and demonstrated in conjunction with the U.S Coast Guard and NOAA National Weather Service as part of the Project Icewarn all weather ice information system for the Great Lakes Winter Navigation Program.

National Waterways Study. Analysis of Navigation Relationships to Other Water Uses.

DTIC Science & Technology

1981-07-01

The Erie Harbor is defined as all of Presque Isle Bay. There are five marinas within the harbor with a total of 1,500 slips and four launching...Lake Erie and two feet at some locations on Lake Ontario. Other natural phenomena causing fluctuations of water levels are ice jams and the growth of...raised Lake Erie 0.23 feet. During the high water periods in the early 1950s and middle 1970s (caused by excessive precipitation) the Ogoki diversions

Joint University Program for Air Transportation Research, 1990-1991

NASA Technical Reports Server (NTRS)

Morrell, Frederick R. (Compiler)

1991-01-01

The goals of this program are consistent with the interests of both NASA and the FAA in furthering the safety and efficiency of the National Airspace System. Research carried out at the Massachusetts Institute of Technology (MIT), Ohio University, and Princeton University are covered. Topics studied include passive infrared ice detection for helicopters, the cockpit display of hazardous windshear information, fault detection and isolation for multisensor navigation systems, neural networks for aircraft system identification, and intelligent failure tolerant control.

Proceedings of the Arctic Oceanography Conference and Workshop Held at the Naval Ocean Research and Development Activity, NSTL, MS on June 11-14, 1985

DTIC Science & Technology

1985-01-01

Patrol (IIP) has been conducted by the U. S. Coast Guard, to provide the North Atlantic Mariner with a warning of hazardous icebergs in the region...of the Grand Banks of Newfoundland. During the iceberg season, March to August, IIP conducts iceberg reconnaissance flights using HC-130 aircraft...Connecticut. 1. INTRODUCTION Icebergs and sea ice have been hazards to navigation in northern waters for centuries, but the threat did not attract

Lunar Navigation Determination System - LaNDS

NASA Technical Reports Server (NTRS)

Quinn, David; Talabac, Stephen

2012-01-01

A portable comprehensive navigational system has been developed that both robotic and human explorers can use to determine their location, attitude, and heading anywhere on the lunar surface independent of external infrastructure (needs no Lunar satellite network, line of sight to the Sun or Earth, etc.). The system combines robust processing power with an extensive topographical database to create a real-time atlas (GIS Geospatial Information System) that is able to autonomously control and monitor both single unmanned rovers and fleets of rovers, as well as science payload stations. The system includes provisions for teleoperation and tele-presence. The system accepts (but does not require) inputs from a wide range of sensors. A means was needed to establish a location when the search is taken deep in a crater (looking for water ice) and out of view of Earth or any other references. A star camera can be employed to determine the user's attitude in menial space and stellar map in body space. A local nadir reference (e.g., an accelerometer that orients the nadir vector in body space) can be used in conjunction with a digital ephemeris and gravity model of the Moon to isolate the latitude, longitude, and azimuth of the user on the surface. That information can be used in conjunction with a Lunar GIS and advanced navigation planning algorithms to aid astronauts (or other assets) to navigate on the Lunar surface.

Analysis of ArcticDEM orthorectification for polar navigational traverses

NASA Astrophysics Data System (ADS)

Menio, E. C.; Deeb, E. J.; Weale, J.; Courville, Z.; Tracy, B.; Cloutier, M. D.; Cothren, J. D.; Liu, J.

2017-12-01

The availability and accessibility of high-resolution satellite imagery allows operational support teams to visually assess physical risks along traverse routes before and during the field season. In support of operations along the Greenland Inland Traverse (GrIT), DigitalGlobe's WorldView 0.5m resolution panchromatic imagery is analyzed to identify and digitize crevasse features along the route from Thule Air Force Base to Summit Station, Greenland. In the spring of 2016, field teams reported up to 150 meters of offset between the location of crevasse features on the ground and the location of the same feature on the imagery provided. Investigation into this issue identified the need to orthorectify imagery—use digital elevation models (DEMs) to correct viewing geometry distortions—to improve navigational accuracy in the field. It was previously thought that orthorectification was not necessary for applications in relatively flat terrain such as ice sheets. However, the surface elevations on the margins of the Greenland Ice Sheet vary enough to cause distortions in imagery, if taken obliquely. As is standard for requests, the Polar Geospatial Center (PGC) provides orthorectified imagery using the MEaSUREs Greenland Ice Mapping Project (GIMP) 30m digital elevation model. Current, higher-resolution elevation datasets, such as the ArcticDEM (2-5m resolution) and WorldView stereopair DEMs (2-3m resolution), are available for use in orthorectification. This study examines three heavily crevassed areas along the GrIT traverse, as identified in 2015 and 2016 imagery. We extracted elevation profiles along the GrIT route from each of the three DEMs: GIMP, ArcticDEM, and WorldView stereopair mosaic. Results show the courser GIMP data deviating significantly from the ArcticDEM and WorldView data, at points by up to 80m, which is seen as offset of features in plan view. In-situ Ground Penetrating Radar (GPR) surveys of crevasse crossings allow for evaluation of geopositional accuracy of each resulting orthorectified photo and a quantitative analysis of plan view offset.

Design of an Autonomous Underwater Vehicle to Calibrate the Europa Clipper Ice-Penetrating Radar

NASA Astrophysics Data System (ADS)

Stone, W.; Siegel, V.; Kimball, P.; Richmond, K.; Flesher, C.; Hogan, B.; Lelievre, S.

2013-12-01

Jupiter's moon Europa has been prioritized as the target for the Europa Clipper flyby mission. A key science objective for the mission is to remotely characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange. This objective is a critical component of the mission's overarching goal of assessing the habitability of Europa. The instrument targeted for addressing key aspects of this goal is an ice-penetrating radar (IPR). As a primary goal of our work, we will tightly couple airborne IPR studies of the Ross Ice Shelf by the Europa Clipper radar team with ground-truth data to be obtained from sub-glacial sonar and bio-geochemical mapping of the corresponding ice-water and water-rock interfaces using an advanced autonomous underwater vehicle (AUV). The ARTEMIS vehicle - a heavily morphed long-range, low drag variant of the highly successful 4-degree-of-freedom hovering sub-ice ENDURANCE bot -- will be deployed from a sea-ice drill hole adjacent the McMurdo Ice Shelf (MIS) and will perform three classes of missions. The first includes original exploration and high definition mapping of both the ice-water interface and the benthic interface on a length scale (approximately 10 kilometers under-ice penetration radius) that will definitively tie it to the synchronous airborne IPR over-flights. These exploration and mapping missions will be conducted at up to 10 different locations along the MIS in order to capture varying ice thickness and seawater intrusion into the ice shelf. Following initial mapping characterization, the vehicle will conduct astrobiology-relevant proximity operations using bio-assay sensors (custom-designed UV fluorescence and machine-vision-processed optical imagery) followed by point-targeted studies at regions of interest. Sample returns from the ice-water interface will be triggered autonomously using real-time-processed instrument data and onboard decision-to-collect algorithms. ARTEMIS will be capable of conducting precision hovering proximity science in an unexplored environment, followed by high speed (1.5 m/s) return to the melt hole. The navigation system will significantly advance upon the successes of the prior DEPTHX and ENDURANCE systems and several novel pose-drift correction technologies will be developed and tested under ice during the project. The method of down-hole deployment and auto-docking return will be extended to a vertically-deployed, horizontally-recovered concept that is depth independent and highly relevant to an ice-water deployment on an icy moon. The presentation will discuss the mission down-select architecture for the ARTEMIS vehicle and its implications for the design of a Europa 'fast mover' carrier AUV, the onboard instrument suite, and the Antarctic mission CONOPS. The vehicle and crew will deploy to Antarctica in the 2015/2016 season.

Environmental impact of exhaust emissions by Arctic shipping.

PubMed

Schröder, Christian; Reimer, Nils; Jochmann, Peter

2017-12-01

Since 2005, a dramatic decline of the Arctic sea-ice extent is observed which results in an increase of shipping activities. Even though this provides commercial and social development opportunities, the resulting environmental impacts need to be investigated and monitored. In order to understand the impact of shipping in arctic areas, the method described in this paper determines the travel time, fuel consumption and resulting exhaust emissions of ships navigating in arctic waters. The investigated case studies are considering ship particulars as well as environmental conditions with special focus on ice scenarios. Travel time, fuel consumption and exhaust gas emission were investigated for three different vessels, using different passages of the Northern Sea Route (NSR) in different seasons of years 1960, 2000 and 2040. The presented results show the sensitivity of vessel performance and amount of exhaust emissions to optimize arctic traffic with respect to efficiency, safety and environmental impact.

Climate Change, Globalization and Geopolitics in the New Maritime Arctic

NASA Astrophysics Data System (ADS)

Brigham, L. W.

2011-12-01

Early in the 21st century a confluence of climate change, globalization and geopolitics is shaping the future of the maritime Arctic. This nexus is also fostering greater linkage of the Arctic to the rest of the planet. Arctic sea ice is undergoing a historic transformation of thinning, extent reduction in all seasons, and reduction in the area of multiyear ice in the central Arctic Ocean. Global Climate Model simulations of Arctic sea ice indicate multiyear ice could disappear by 2030 for a short period of time each summer. These physical changes invite greater marine access, longer seasons of navigation, and potential, summer trans-Arctic voyages. As a result, enhanced marine safety, environmental protection, and maritime security measures are under development. Coupled with climate change as a key driver of regional change is the current and future integration of the Arctic's natural wealth with global markets (oil, gas and hard minerals). Abundant freshwater in the Arctic could also be a future commodity of value. Recent events such as drilling for hydrocarbons off Greenland's west coast and the summer marine transport of natural resources from the Russian Arctic to China across the top of Eurasia are indicators of greater global economic ties to the Arctic. Plausible Arctic futures indicate continued integration with global issues and increased complexity of a range of regional economic, security and environmental challenges.

Generation of a high-accuracy regional DEM based on ALOS/PRISM imagery of East Antarctica

NASA Astrophysics Data System (ADS)

Shiramizu, Kaoru; Doi, Koichiro; Aoyama, Yuichi

2017-12-01

A digital elevation model (DEM) is used to estimate ice-flow velocities for an ice sheet and glaciers via Differential Interferometric Synthetic Aperture Radar (DInSAR) processing. The accuracy of DInSAR-derived displacement estimates depends upon the accuracy of the DEM. Therefore, we used stereo optical images, obtained with a panchromatic remote-sensing instrument for stereo mapping (PRISM) sensor mounted onboard the Advanced Land Observing Satellite (ALOS), to produce a new DEM ("PRISM-DEM") of part of the coastal region of Lützow-Holm Bay in Dronning Maud Land, East Antarctica. We verified the accuracy of the PRISM-DEM by comparing ellipsoidal heights with those of existing DEMs and values obtained by satellite laser altimetry (ICESat/GLAS) and Global Navigation Satellite System surveying. The accuracy of the PRISM-DEM is estimated to be 2.80 m over ice sheet, 4.86 m over individual glaciers, and 6.63 m over rock outcrops. By comparison, the estimated accuracy of the ASTER-GDEM, widely used in polar regions, is 33.45 m over ice sheet, 14.61 m over glaciers, and 19.95 m over rock outcrops. For displacement measurements made along the radar line-of-sight by DInSAR, in conjunction with ALOS/PALSAR data, the accuracy of the PRISM-DEM and ASTER-GDEM correspond to estimation errors of <6.3 mm and <31.8 mm, respectively.

Earth Observations taken by Expedition 30 crewmember

NASA Image and Video Library

2012-03-15

ISS030-E-162344 (15 March 2012) --- Ice floes along the Kamchatka coastline are featured in this image photographed by an Expedition 30 crew member on the International Space Station. The vantage point from orbit frequently affords the opportunity to observe processes that are impossible to see on the ground – or in this case the northeastern Pacific Ocean. The winter season blankets the Kamchatka Peninsula of Russia in snow, but significant amounts of sea ice can also form and collect along the coastline. As ice floes grind against each other, they produce smaller floes that can be moved by wind and water currents acting along the coastline. The irregular southeastern coastline of Kamchatka helps to produce large circular eddy currents from the main southwestward-flowing Kamchatka current. Three such eddies are clearly highlighted by surface ice floe patterns at center. The ice patterns are very difficult (and dangerous) to navigate in an ocean vessel – while the floes may look thin and delicate from the space station vantage point, even the smaller ice chunks are likely several meters across. White clouds at top right are distinguished from the sea ice and snow cover in the image by their high brightness and discontinuous nature. The Kamchatka Peninsula also hosts many currently and historically active stratovolcanoes. Kliuchevskoi Volcano, the highest in Kamchatka (summit elevation 4,835 meters) and one of the most active, had its most recent confirmed eruption in June of 2011, while Karymsky Volcano to the south likely produced ash plumes days before this image was taken; the snow cover near the volcano to the south and east of the summit is darkened, probably due to a cover of fresh ash, or melted away altogether (bottom center). In contrast, Kronotsky Volcano – a “textbook” symmetrical cone-shaped stratovolcano – last erupted in 1923.

Software for a GPS-Reflection Remote-Sensing System

NASA Technical Reports Server (NTRS)

Lowe, Stephen

2003-01-01

A special-purpose software Global Positioning System (GPS) receiver designed for remote sensing with reflected GPS signals is described in Delay/Doppler-Mapping GPS-Reflection Remote-Sensing System (NPO-30385), which appears elsewhere in this issue of NASA Tech Briefs. The input accepted by this program comprises raw (open-loop) digitized GPS signals sampled at a rate of about 20 MHz. The program processes the data samples to perform the following functions: detection of signals; tracking of phases and delays; mapping of delay, Doppler, and delay/Doppler waveforms; dual-frequency processing; coherent integrations as short as 125 s; decoding of navigation messages; and precise time tagging of observable quantities. The software can perform these functions on all detectable satellite signals without dead time. Open-loop data collected over water, land, or ice and processed by this software can be further processed to extract geophysical information. Possible examples include mean sea height, wind speed and direction, and significant wave height (for observations over the ocean); bistatic-radar terrain images and measures of soil moisture and biomass (for observations over land); and estimates of ice age, thickness, and surface density (for observations over ice).

ERTS imagery applied to Alaskan coastal problems. [surface water circulation

NASA Technical Reports Server (NTRS)

Wright, F. F.; Sharma, G. D.; Burbank, D. C.; Burns, J. J.

1974-01-01

Along the Alaska coast, surface water circulation is relatively easy to study with ERTS imagery. Highly turbid river water, sea ice, and fluvial ice have proven to be excellent tracers of the surface waters. Sea truth studies in the Gulf of Alaska, Cook Inlet, Bristol Bay, and the Bering Strait area have established the reliability of these tracers. ERTS imagery in the MSS 4 and 5 bands is particularly useful for observing lower concentrations of suspended sediment, while MSS 6 data is best for the most concentrated plumes. Ice features are most clearly seen on MSS 7 imagery; fracture patterns and the movement of specific floes can be used to map circulation in the winter when runoff is restricted, if appropriate allowance is made for wind influence. Current patterns interpreted from satellite data are only two-dimensional, but since most biological activity and pollution are concentrated near the surface, the information developed can be of direct utility. Details of Alaska inshore circulation of importance to coastal engineering, navigation, pollution studies, and fisheries development have been clarified with satellite data. ERTS has made possible the analysis of circulation in many parts of the Alaskan coast.

Sustaining observations in the polar oceans.

PubMed

Abrahamsen, E P

2014-09-28

Polar oceans present a unique set of challenges to sustained observations. Sea ice cover restricts navigation for ships and autonomous measurement platforms alike, and icebergs present a hazard to instruments deployed in the upper ocean and in shelf seas. However, the important role of the poles in the global ocean circulation provides ample justification for sustained observations in these regions, both to monitor the rapid changes taking place, and to better understand climate processes in these traditionally poorly sampled areas. In the past, the vast majority of polar measurements took place in the summer. In recent years, novel techniques such as miniature CTD (conductivity-temperature-depth) tags carried by seals have provided an explosion in year-round measurements in areas largely inaccessible to ships, and, as ice avoidance is added to autonomous profiling floats and gliders, these promise to provide further enhancements to observing systems. In addition, remote sensing provides vital information about changes taking place in sea ice cover at both poles. To make these observations sustainable into the future, improved international coordination and collaboration is necessary to gain optimum utilization of observing networks. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Testing of SIR (a transformable robotic submarine) in Lake Tahoe for future deployment at West Antarctic Ice Sheet grounding lines of Siple Coast

NASA Astrophysics Data System (ADS)

Powell, R. D.; Scherer, R. P.; Griffiths, I.; Taylor, L.; Winans, J.; Mankoff, K. D.

2011-12-01

A remotely operated vehicle (ROV) has been custom-designed and built by DOER Marine to meet scientific requirements for exploring subglacial water cavities. This sub-ice rover (SIR) will explore and quantitatively document the grounding zone areas of the Ross Ice Shelf cavity using a 3km-long umbilical tether by deployment through an 800m-long ice borehole in a torpedo shape, which is also its default mode if operational failure occurs. Once in the ocean cavity it transforms via a diamond-shaped geometry into a rectangular form when all of its instruments come alive in its flight mode. Instrumentation includes 4 cameras (one forward-looking HD), a vertical scanning sonar (long-range imaging for spatial orientation and navigation), Doppler current meter (determine water current velocities), multi-beam sonar (image and swath map bottom topography), sub-bottom profiler (profile sub-sea-floor sediment for geological history), CTD (determine salinity, temperature and depth), DO meter (determine dissolved oxygen content in water), transmissometer (determine suspended particulate concentrations in water), laser particle-size analyzer (determine sizes of particles in water), triple laser-beams (determine size and volume of objects), thermistor probe (measure in situ temperatures of ice and sediment), shear vane probe (determine in situ strength of sediment), manipulator arm (deploy instrumentation packages, collect samples), shallow ice corer (collect ice samples and glacial debris), water sampler (determine sea water/freshwater composition, calibrate real-time sensors, sample microbes), shallow sediment corer (sample sea floor, in-ice and subglacial sediment for stratigraphy, facies, particle size, composition, structure, fabric, microbes). A sophisticated array of data handling, storing and displaying will allow real-time observations and environmental assessments to be made. This robotic submarine and other instruments will be tested in Lake Tahoe in September, 2011 and results will be presented on its trials and geological and biological findings down to the deepest depths of the lake. Other instruments include a 5m-ling percussion corer for sampling deeper sediments, an ice-tethered profiler with CTD and ACDP, and in situ oceanographic mooring designed to fit down a narrow (30cm-diameter) ice borehole that include interchangeable packages of ACDPs, CTDs, transmissometers, laser particle-size analyzer, DO meter, automated multi-port water sampler, water column nutrient analyzer, sediment porewater chemistry analyzer, down-looking color camera (see figure), and altimeter.

Ship accessibility predictions for the Arctic Ocean based on IPCC CO2 emission scenarios

NASA Astrophysics Data System (ADS)

Oh, Jai-Ho; Woo, Sumin; Yang, Sin-Il

2017-02-01

Changes in the extent of Arctic sea ice, which have resulted from climate change, offer new opportunities to use the Northern Sea Route (NSR) and Northwest Passage (NWP) for shipping. However, choosing to navigate the Arctic Ocean remains challenging due to the limited accessibility of ships and the balance between economic gain and potential risk. As a result, more precise and detailed information on both weather and sea ice change in the Arctic are required. In this study, a high-resolution global AGCM was used to provide detailed information on the extent and thickness of Arctic sea ice. For this simulation, we have simulated the AMIP-type simulation for the present-day climate during 31 years from 1979 to 2009 with observed SST and Sea Ice concentration. For the future climate projection, we have performed the historical climate during 1979-2005 and subsequently the future climate projection during 2010-2099 with mean of four CMIP5 models due to the two Representative Concentration Pathway scenarios (RCP 8.5 and RCP 4.5). First, the AMIP-type simulation was evaluated by comparison with observations from the Hadley Centre sea-ice and Sea Surface Temperature (HadlSST) dataset. The model reflects the maximum (in March) and minimum (in September) sea ice extent and annual cycle. Based on this validation, the future sea ice extents show the decreasing trend for both the maximum and minimum seasons and RCP 8.5 shows more sharply decreasing patterns of sea ice than RCP 4.5. Under both scenarios, ships classified as Polar Class (PC) 3 and Open-Water (OW) were predicted to have the largest and smallest number of ship-accessible days (in any given year) for the NSR and NWP, respectively. Based on the RCP 8.5 scenario, the projections suggest that after 2070, PC3 and PC6 vessels will have year-round access across to the Arctic Ocean. In contrast, OW vessels will continue to have a seasonal handicap, inhibiting their ability to pass through the NSR and NWP.

The global signature of post-1900 land ice wastage on vertical land motion

NASA Astrophysics Data System (ADS)

Riva, Riccardo; Frederikse, Thomas; King, Matt; Marzeion, Ben; van den Broeke, Michiel

2017-04-01

The amount of ice stored on land has strongly declined during the 20th century, and melt rates showed a significant acceleration over the last two decades. Land ice wastage is well known to be one of the main drivers of global mean sea-level rise, as widely discussed in the literature and reflected in the last assessment report of the IPCC. A less obvious effect of melting land ice is the response of the solid earth to mass redistribution on its surface, which, in the first approximation, results in land uplift where the load reduces (e.g., close to the meltwater sources) and land subsidence where the load increases (e.g., under the rising oceans). This effect is nowadays well known within the cryospheric and sea level communities. However, what is often not realized is that the solid earth response is a truly global effect: a localized mass change does cause a large deformation signal in its proximity, but also causes a change of the position of every other point on the Earth's surface. The theory of the Earth's elastic response to changing surface loads forms the basis of the 'sea-level equation', which allows sea-level fingerprints of continental mass change to be computed. In this paper, we provide the first dedicated analysis of global vertical land motion driven by land ice wastage. By means of established techniques to compute the solid earth elastic response to surface load changes and the most recent datasets of glacier and ice sheet mass change, we show that land ice loss currently leads to vertical deformation rates of several tenths of mm per year at mid-latitudes, especially over the Northern Hemisphere where most sources are located. In combination with the improved accuracy of space geodetic techniques (e.g., Global Navigation Satellite Systems), this means that the effect of ice melt is non-negligible over a large part of the continents. In particular, we show how deformation rates have been strongly varying through the last century, which implies that they should be properly modelled before interpreting and extrapolating recent observations of vertical land motion and sea level change.

More than the sum of its parts? A merged satellite product from MODIS and AMSR2 sea ice concentration

NASA Astrophysics Data System (ADS)

Ludwig, V. S.; Istomina, L.; Spreen, G.

2017-12-01

Arctic sea ice concentration (SIC), the fraction of a grid cell that is covered by sea ice, is relevant for a multitude of branches: physics (heat/momentum exchange), chemistry (gas exchange), biology (photosynthesis), navigation (location of pack ice) and others. It has been observed from passive microwave (PMW) radiometers on satellites continuously since 1979, providing an almost 40-year time series. However, the resolution is limited to typically 25 km which is good enough for climate studies but too coarse to properly resolve the ice edge or to show leads. The highest resolution from PMW sensors today is 5 km of the AMSR2 89 GHz channels. Thermal infrared (TIR) and visible (VIS) measurements provide much higher resolutions between 1 km (TIR) and 30 m (VIS, regional daily coverage). The higher resolutions come at the cost of depending on cloud-free fields of view (TIR and VIS) and daylight (VIS). We present a merged product of ASI-AMSR2 SIC (PMW) and MODIS SIC (TIR) at a nominal resolution of 1 km. This product benefits from both the independence of PMW towards cloud coverage and the high resolution of TIR data. An independent validation data set has been produced from manually selected, cloud-free Landsat VIS data at 30 m resolution. This dataset is used to evaluate the performance of the merged SIC dataset. Our results show that the merged product resolves features which are smeared out by the PMW data while benefitting from the PMW data in cloudy cases and is thus indeed more than the sum of its parts.

Single pilot IFR operating problems determined from accidental data analysis

NASA Technical Reports Server (NTRS)

Forsyth, D. L.; Shaughnessy, J. D.

1978-01-01

The accident reports examined were restricted to instrument rated pilots flying in IFR weather. A brief examination was made of accidents which occurred during all phases of flight and which were due to all causes. A detailed examination was made of those accidents which involved a single pilot which occurred during the landing phases of flight, and were due to pilot error. Problem areas found include: (1) landing phase operations especially final approach, (2) pilot weather briefings, (3) night approaches in low IFR weather, (4) below minimum approaches, (5) aircraft icing, (6) imprecise navigation, (7) descending below minimum IFR altitudes, (8) fuel mismanagement, (9) pilot overconfidence, and (10) high pilot workload especially in twins. Some suggested areas of research included: (1) low cost deicing systems, (2) standardized navigation displays, (3) low cost low-altitude warning systems, (4) improved fuel management systems, (5) improved ATC communications, (6) more effective pilot training and experience acquisition methods, and (7) better weather data dissemination techniques.

An Array of Ice-Based Observatories for Arctic Studies

NASA Astrophysics Data System (ADS)

Plueddemann, A.; Proshutinsky, A.; Toole, J.; Ashjian, C.; Krishfield, R.; Carmack, E.; Dethloff, K.; Fahrbach, E.; Gascard, J.; Perovich, D.; Pryamikov, S.

2004-12-01

The Arctic Ocean's role in global climate - while now widely appreciated - remains poorly understood. Lack of information about key processes within the oceanic, cryospheric, biologic, atmospheric and geologic disciplines will continue to impede physical understanding, model validation, and climate prediction until a practical observing system is designed and implemented. Requirements, challenges and recommendations for Ice-Based Observatories (IBO?s) for the Arctic Ocean were formulated by workshop participants of an international workshop entitled "Arctic Observing Based on Ice-Tethered Platforms" held at the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts, USA, June 28-30, 2004. The principal conclusion from the workshop was that practical, cost-effective and proven IBO designs presently exist, can be readily extended to provide interdisciplinary observations, and should be implemented expeditiously as part of a coordinated Arctic observing system. Ice-based instrument systems are a proven means of acquiring unattended high quality air, ice, and ocean data from the central Arctic during all seasons. Arctic Change is ongoing and measurements need to begin now. An array of approximately 25-30 IBO units maintained throughout the Arctic Ocean is envisioned to observe the annual and interannual variations of the polar atmosphere-ice-ocean environment. An international body will be required to coordinate the various national programs (eliminate overlap, insure no data holes) and insure compatibility of data and their widespread distribution. A long-term, internationally coordinated logistics plan should be implemented as an essential complement to scientific and technical plans for an IBO array. The 25 years of IABP drift trajectories, existing data climatologies and available numerical simulations should be exploited to derive insight to optimal array design, deployment strategies, sampling intervals, and expected performance of an IBO array. IBO designs should provide accommodation for novel sensors, tomographic receivers, and communication and navigation capabilities for free vehicles. Emerging technologies for Arctic observation should be developed within the framework of an integrated Arctic observing system.

Altimeter Observations of Wave Climate in the Arctic Ocean

NASA Astrophysics Data System (ADS)

Babanin, A. V.; Liu, Q.; Zieger, S.

2016-02-01

Wind waves are a new physical phenomenon to the Arctic Seas, which in the past were covered with ice. Now, over summer months, ice coverage retreats up to high latitudes and waves are generated. The marginal open seas provide new opportunities and new problems. Navigation and other maritime activities become possible, but wave heights, storm surges and coastal erosion will likely increase. Air-sea interactions enter a completely new regime, with momentum, energy, heat, gas and moisture fluxes being moderated or produced by the waves, and impacting on upper-ocean mixing. All these issues require knowledge of the wave climate. We will report results of investigation of wave climate and its trends by means of satellite altimetry. This is a challenging, but important topic. On one hand, no statistical approach is possible since in the past for most of the Arctic Ocean there was limited wave activity. Extrapolations of the current observations into the future are not feasible, because ice cover and wind patterns in the Arctic are changing. On the other hand, information on the mean and extreme wave properties, such as wave height, period, direction, on the frequency of occurrence and duration of the storms is of great importance for oceanographic, meteorological, climate, naval and maritime applications in the Arctic Seas.

The NASA CYGNSS mission: a pathfinder for GNSS scatterometry remote sensing applications

NASA Astrophysics Data System (ADS)

Rose, Randy; Gleason, Scott; Ruf, Chris

2014-10-01

Global Navigation Satellite System (GNSS) based scatterometry offers breakthrough opportunities for wave, wind, ice, and soil moisture remote sensing. Recent developments in electronics and nano-satellite technologies combined with modeling techniques developed over the past 20 years are enabling a new class of remote sensing capabilities that present more cost effective solutions to existing problems while opening new applications of Earth remote sensing. Key information about the ocean and global climate is hidden from existing space borne observatories because of the frequency band in which they operate. Using GNSS-based bi-static scatterometry performed by a constellation of microsatellites offers remote sensing of ocean wave, wind, and ice data with unprecedented temporal resolution and spatial coverage across the full dynamic range of ocean wind speeds in all precipitating conditions. The NASA Cyclone Global Navigation Satellite System (CYGNSS) is a space borne mission being developed to study tropical cyclone inner core processes. CYGNSS consists of 8 GPS bi-static radar receivers to be deployed on separate micro-satellites in October 2016. CYGNSS will provide data to address what are thought to be the principle deficiencies with current tropical cyclone intensity forecasts: inadequate observations and modeling of the inner core. The inadequacy in observations results from two causes: 1) Much of the inner core ocean surface is obscured from conventional remote sensing instruments by intense precipitation in the eye wall and inner rain bands. 2) The rapidly evolving (genesis and intensification) stages of the tropical cyclone life cycle are poorly sampled in time by conventional polar-orbiting, wide-swath surface wind imagers. It is anticipated that numerous additional Earth science applications can also benefit from the cost effective high spatial and temporal sampling capabilities of GNSS remote sensing. These applications include monitoring of rough and dangerous sea states, global observations of sea ice cover and extent, meso-scale ocean circulation studies, and near surface soil moisture observations. This presentation provides a primer for GNSS based scatterometry, an overview of NASA's CYGNSS mission and its expected performance, as well as a summary of possible other GNSS based remote sensing applications.

C- and L-band space-borne SAR incidence angle normalization for efficient Arctic sea ice monitoring

NASA Astrophysics Data System (ADS)

Mahmud, M. S.; Geldsetzer, T.; Howell, S.; Yackel, J.; Nandan, V.

2017-12-01

C-band Synthetic Aperture Radar (SAR) has been widely used effectively for operational sea ice monitoring, owing to its greater seperability between snow-covered first-year (FYI) and multi-year (MYI) ice types, during winter. However, during the melt season, C-band SAR backscatter contrast reduces between FYI and MYI. To overcome the limitations of C-band, several studies have recommended utlizing L-band SAR, as it has the potential to significantly improve sea ice classification. Given its longer wavelength, L-band can efficiently separate FYI and MYI types, especially during melt season. Therefore, the combination of C- and L-band SAR is an optimal solution for efficient seasonal sea ice monitoring. As SAR acquires images over a range of incidence angles from near-range to far-range, SAR backscatter varies substantially. To compensate this variation in SAR backscatter, incidence angle dependency of C- and L-band SAR backscatter for different FYI and MYI types is crucial to quantify, which is the objective of this study. Time-series SAR imagery from C-band RADARSAT-2 and L-band ALOS PALSAR during winter months of 2010 across 60 sites over the Canadian Arctic was acquired. Utilizing 15 images for each sites during February-March for both C- and L-band SAR, incidence angle dependency was calculated. Our study reveals that L- and C-band backscatter from FYI and MYI decreases with increasing incidence angle. The mean incidence angle dependency for FYI and MYI were estimated to be -0.21 dB/1° and -0.30 dB/1° respectively from L-band SAR, and -0.22 dB/1° and -0.16 dB/1° from C-band SAR, respectively. While the incidence angle dependency for FYI was found to be similar in both frequencies, it doubled in case of MYI from L-band, compared to C-band. After applying the incidence angle normalization method to both C- and L-band SAR images, preliminary results indicate improved sea ice type seperability between FYI and MYI types, with substantially lower number of mixed pixels; thereby offering more reliable sea ice classification accuracies. Research findings from this study can be utilized to improve seasonal sea ice classification with higher accuracy for operational Arctic sea ice monitoring, especially in regions like the Canadian Arctic, where MYI detection is crucial for safer ship navigations.

Detection and Analysis of High Ice Concentration Events and Supercooled Drizzle from IAGOS Commercial Aircraft

NASA Astrophysics Data System (ADS)

Gallagher, Martin; Baumgardner, Darrel; Lloyd, Gary; Beswick, Karl; Freer, Matt; Durant, Adam

2016-04-01

Hazardous encounters with high ice concentrations that lead to temperature and airspeed sensor measurement errors, as well as engine rollback and flameout, continue to pose serious problems for flight operations of commercial air carriers. Supercooled liquid droplets (SLD) are an additional hazard, especially for smaller commuter aircraft that do not have sufficient power to fly out of heavy icing conditions or heat to remove the ice. New regulations issued by the United States and European regulatory agencies are being implemented that will require aircraft below a certain weight class to carry sensors that will detect and warn of these types of icing conditions. Commercial aircraft do not currently carry standard sensors to detect the presence of ice crystals in high concentrations because they are typical found in sizes that are below the detection range of aircraft weather radar. Likewise, the sensors that are currently used to detect supercooled water do not respond well to drizzle-sized drops. Hence, there is a need for a sensor that can fill this measurement void. In addition, the forecast models that are used to predict regions of icing rely on pilot observations as the only means to validate the model products and currently there are no forecasts for the prevalence of high altitude ice crystals. Backscatter Cloud Probes (BCP) have been flying since 2011 under the IAGOS project on six Airbus commercial airliners operated by Lufthansa, Air France, China Air, Iberia and Cathay Pacific, and measure cloud droplets, ice crystals and aerosol particles larger than 5 μm. The BCP can detect these particles and measures an optical equivalent diameter (OED) but is not able to distinguish the type of particle, i.e. whether they are droplets, ice crystals, dust or ash. However, some qualification can be done based on measured temperature to discriminate between liquid water and ice. The next generation BCP (BCPD, Backscatter Cloud Probe with polarization detection) is now undergoing performance testing and can differentiate atmospheric particle types. Given that the BCP and BCPD are both single particle detectors, this permits high sensitivity to the smallest quantities and rapid detection (within seconds) to alert flight crews. The BCPD is being implemented as part of a near real-time, flight forecasting system that uses satellite and models, coupled with in situ measurements from the BCPD and meteorological sensors. DAEDALUS is a weather threat situational awareness system for commercial aircraft currently funded by the European Space Agency and supported by major aircraft and engine manufacturers, airlines and air navigation service providers. This presentation will describe the essential components of DAEDALUS and how it will be implemented to optimize aircraft flight paths while minimizing potential hazards. Examples of measurements from the BCPD will be given that demonstrate its capability for detection and differentiation of atmospheric particulates, especially supercooled liquid droplets and ice crystals, in near real-time.

Radio science with Voyager 2 at Uranus - Results on masses and densities of the planet and five principal satellites

NASA Technical Reports Server (NTRS)

Anderson, J. D.; Campbell, J. K.; Jacobson, R. A.; Sweetnam, D. N.; Taylor, A. H.

1987-01-01

Phase-coherent Doppler data generated by the Deep Space Network with the radio communication system during the Voyager 2 encounter with Uranus in January 1986, optical navigation data generated by the Voyager Navigation Team with the Voyager 2 imaging system, and ground-based astrometric data obtained over an 8-yr period are compiled and analyzed to determine the masses and densities of Uranus and its principal satellites. The data-analysis procedures are explained in detail, and the results are presented in tables and graphs. The mean density of Uranus is found to be 1.285 + or - 0.001 g/cu cm, whereas the mean uncompressed mass of all five satellites is 1.48 + or - 0.06 g/cu cm, or 0.10 g/cu cm above the density expected for a homogeneous solar mix of rock, H2O and NH3 ice, and CH4 as clathrate hydrate. This difference is tentatively attributed to the presence of 15 mass percent of pure graphite, which would provide the thermal conductivity required to keep the satellites cold and undifferentiated.

Towards breaking the spatial resolution barriers: An optical flow and super-resolution approach for sea ice motion estimation

NASA Astrophysics Data System (ADS)

Petrou, Zisis I.; Xian, Yang; Tian, YingLi

2018-04-01

Estimation of sea ice motion at fine scales is important for a number of regional and local level applications, including modeling of sea ice distribution, ocean-atmosphere and climate dynamics, as well as safe navigation and sea operations. In this study, we propose an optical flow and super-resolution approach to accurately estimate motion from remote sensing images at a higher spatial resolution than the original data. First, an external example learning-based super-resolution method is applied on the original images to generate higher resolution versions. Then, an optical flow approach is applied on the higher resolution images, identifying sparse correspondences and interpolating them to extract a dense motion vector field with continuous values and subpixel accuracies. Our proposed approach is successfully evaluated on passive microwave, optical, and Synthetic Aperture Radar data, proving appropriate for multi-sensor applications and different spatial resolutions. The approach estimates motion with similar or higher accuracy than the original data, while increasing the spatial resolution of up to eight times. In addition, the adopted optical flow component outperforms a state-of-the-art pattern matching method. Overall, the proposed approach results in accurate motion vectors with unprecedented spatial resolutions of up to 1.5 km for passive microwave data covering the entire Arctic and 20 m for radar data, and proves promising for numerous scientific and operational applications.

Evaluation of an operational water cycle prediction system for the Laurentian Great Lakes and St. Lawrence River

NASA Astrophysics Data System (ADS)

Fortin, Vincent; Durnford, Dorothy; Smith, Gregory; Dyck, Sarah; Martinez, Yosvany; Mackay, Murray; Winter, Barbara

2017-04-01

Environment and Climate Change Canada (ECCC) is implementing new numerical guidance products based on fully coupled numerical models to better inform the public as well as specialized users on the current and future state of various components of the water cycle, including stream flow and water levels. Outputs from this new system, named the Water Cycle Prediction System (WCPS), have been available for the Great Lakes and St. Lawrence River watershed since June 2016. WCPS links together ECCC's weather forecasting model, GEM, the 2-D ice model C-ICE, the 3-D lake and ocean model NEMO, and a 2-D hydrological model, WATROUTE. Information concerning the water cycle is passed between the models at intervals varying from a few minutes to one hour. It currently produces two forecasts per day for the next three days of the complete water cycle in the Great Lakes region, the largest freshwater lake system in the world. Products include spatially-varying precipitation, evaporation, river discharge, water level anomalies, surface water temperatures, ice coverage, and surface currents. These new products are of interest to water resources and management authority, flood forecasters, hydroelectricity producers, navigation, environmental disaster managers, search and rescue teams, agriculture, and the general public. This presentation focuses on the evaluation of various elements forecasted by the system, and weighs the advantages and disadvantages of running the system fully coupled.

Vermilion Harbor, Ohio. Condition Survey Report. Study of the Impact of the Offshore Breakwater on A. Municipal Water Supply. B. Swimming Area and Beaches. C. Ice Jam Flooding. D. Free-Flow Flooding. E. Sedimentation. F. Navigation. G. Aesthetics.

DTIC Science & Technology

1982-09-01

greater than the presently authorized 12-foot channel in Vermilion Harbor). It is the pur- pose of this study to determine which of the four ...963 A 94 VERMILION HARBOR, OHIO CONDITION SURVEY REPORT STUDY OF THE IMPACT OF THE OFFSHORE BREAKWATER ON A. MUNICIPAL WATER SUPPLY B. SWIMMING AREA...a result of the breakwater construction. Seven possible adverse impacts were identified and studied . These impacts DomS 143 Imna or I Moves is OSOLETE

Variability and Change in the Canadian Cryosphere: A Canadian Science Contribution to International Polar Year

NASA Astrophysics Data System (ADS)

Walker, A. E.; Derksen, C.

2008-12-01

The cryosphere (snow, permafrost and seasonally frozen ground, ice caps and glaciers, sea-, river-, and lake ice) represents a significant feature of the Canadian landscape that impacts climate, hydrology, the economy and the daily lives of all Canadians, especially those living in northern communities. Over the past few decades significant changes have been observed in cryospheric elements (e.g. decreases in snow cover, glacier extent, sea ice cover) that have been attributed to a warming climate. This poster presentation will highlight initial scientific results from the approved Canadian International Polar Year project "Variability and Change in the Canadian Cryosphere" that is being led by Environment Canada and involves 33 co- investigators from government, academia and the private sector and links with international collaborators. This project builds on Canadian strengths in remote sensing, climate analysis and modeling with the overall objective to observe and understand the current state of the cryosphere in Canada and determine how fast it is changing and why. Research activities are focused on: (1) developing new satellite-based capabilities to provide information on the current state of the Canadian cryosphere during the IPY period; (2) placing current cryospheric conditions in the context of the historical record to document the magnitude of changes over the 50 years since the last International Polar Year (IGY 1957-1958); (3) characterizing and explaining the observed variability and changes in the context of the coupled climate cryosphere system; and (4) improving the representation of the cryosphere in Canadian land surface and climate models to provide current and future climate simulations of the cryosphere for climate impact studies. The project also includes several outreach activities to engage northern communities in cryospheric monitoring and incorporate traditional knowledge with remotely-sensed information to generate new maps on local river ice and sea ice conditions to assist residents in planning safe navigation routes.

Modelling Greenland icebergs

NASA Astrophysics Data System (ADS)

Marson, Juliana M.; Myers, Paul G.; Hu, Xianmin

2017-04-01

The Atlantic Meridional Overturning Circulation (AMOC) is well known for carrying heat from low to high latitudes, moderating local temperatures. Numerical studies have examined the AMOC's variability under the influence of freshwater input to subduction and deep convections sites. However, an important source of freshwater has often been overlooked or misrepresented: icebergs. While liquid runoff decreases the ocean salinity near the coast, icebergs are a gradual and remote source of freshwater - a difference that affects sea ice cover, temperature, and salinity distribution in ocean models. Icebergs originated from the Greenland ice sheet, in particular, can affect the subduction process in Labrador Sea by decreasing surface water density. Our study aims to evaluate the distribution of icebergs originated from Greenland and their contribution to freshwater input in the North Atlantic. To do that, we use an interactive iceberg module coupled with the Nucleus for European Modelling of the Ocean (NEMO v3.4), which will calve icebergs from Greenland according to rates established by Bamber et al. (2012). Details on the distribution and trajectory of icebergs within the model may also be of use for understanding potential navigation threats, as shipping increases in northern waters.

Calibration and evaluation of a magnetically tracked ICE probe for guidance of left atrial ablation therapy

NASA Astrophysics Data System (ADS)

Linte, Cristian A.; Rettmann, Maryam E.; Dilger, Ben; Gunawan, Mia S.; Arunachalam, Shivaram P.; Holmes, David R., III; Packer, Douglas L.; Robb, Richard A.

2012-02-01

The novel prototype system for advanced visualization for image-guided left atrial ablation therapy developed in our laboratory permits ready integration of multiple imaging modalities, surgical instrument tracking, interventional devices and electro-physiologic data. This technology allows subject-specific procedure planning and guidance using 3D dynamic, patient-specific models of the patient's heart, augmented with real-time intracardiac echocardiography (ICE). In order for the 2D ICE images to provide intuitive visualization for accurate catheter to surgical target navigation, the transducer must be tracked, so that the acquired images can be appropriately presented with respect to the patient-specific anatomy. Here we present the implementation of a previously developed ultrasound calibration technique for a magnetically tracked ICE transducer, along with a series of evaluation methods to ensure accurate imaging and faithful representation of the imaged structures. Using an engineering-designed phantom, target localization accuracy is assessed by comparing known target locations with their transformed locations inferred from the tracked US images. In addition, the 3D volume reconstruction accuracy is also estimated by comparing a truth volume to that reconstructed from sequential 2D US images. Clinically emulating validation studies are conducted using a patient-specific left atrial phantom. Target localization error of clinically-relevant surgical targets represented by nylon fiducials implanted within the endocardial wall of the phantom was assessed. Our studies have demonstrated 2.4 +/- 0.8 mm target localization error in the engineering-designed evaluation phantoms, 94.8 +/- 4.6 % volume reconstruction accuracy, and 3.1 +/- 1.2 mm target localization error in the left atrial-mimicking phantom. These results are consistent with those disseminated in the literature and also with the accuracy constraints imposed by the employed technology and the clinical application.

AURORA BOREALIS - European Research Icebreaker With Drilling Capability

NASA Astrophysics Data System (ADS)

Biebow, N.; Lembke-Jene, L.; Kunz-Pirrung, M.; Thiede, J.

2008-12-01

The polar oceans are the least known areas of the globe, in although they hold the key to many of our climate´s secrets. How does the sea ice coverage and the sea water properties change? How do plants and animals survive under the most extreme conditions of the earth? Which information of past climate change can be read from the sediments at the sea-floor and how can the future changing climate be predicted? In order to answer such and further questions, for the moment a hypermodern research vessel, the AURORA BOREALIS, is planned, which can handle the cool summers and freezing winters of the polar oceans and which can drill deep into the sea floor. AURORA BOREALIS will be the most advanced Research Icebreaker in the world with a multi-functional role of drilling in deep ocean basins and supporting climate/environmental research and decision support for stakeholder governments for the next 35-40 years. It will have a high icebreaking capacity to penetrate autonomously (single ship operation) into the central Arctic Ocean with more than 2.5 meters of ice cover, during all seasons of the year. The new technological features will include dynamic positioning in closed sea- ice cover, satellite navigation and ice-management support and the deployment and operation of Remotely Operated Vehicles (ROV) and Autonomous Underwater Vehicles (AUVs) from the twin moon-pools. A unique feature of the vessel is the deep-sea drilling rig, which will enable sampling of the ocean floor and sub-sea up to 5000 m water and 1000 m penetration at the most inhospitable places on earth. The drilling capability will be deployed in both Polar Regions on the long run and AURORA BOREALIS will be the only vessel worldwide that could undertake this type of scientific investigation.

Innovative Camera and Image Processing System to Characterize Cryospheric Changes

NASA Astrophysics Data System (ADS)

Schenk, A.; Csatho, B. M.; Nagarajan, S.

2010-12-01

The polar regions play an important role in Earth’s climatic and geodynamic systems. Digital photogrammetric mapping provides a means for monitoring the dramatic changes observed in the polar regions during the past decades. High-resolution, photogrammetrically processed digital aerial imagery provides complementary information to surface measurements obtained by laser altimetry systems. While laser points accurately sample the ice surface, stereo images allow for the mapping of features, such as crevasses, flow bands, shear margins, moraines, leads, and different types of sea ice. Tracking features in repeat images produces a dense velocity vector field that can either serve as validation for interferometrically derived surface velocities or it constitutes a stand-alone product. A multi-modal, photogrammetric platform consists of one or more high-resolution, commercial color cameras, GPS and inertial navigation system as well as optional laser scanner. Such a system, using a Canon EOS-1DS Mark II camera, was first flown on the Icebridge missions Fall 2009 and Spring 2010, capturing hundreds of thousands of images at a frame rate of about one second. While digital images and videos have been used for quite some time for visual inspection, precise 3D measurements with low cost, commercial cameras require special photogrammetric treatment that only became available recently. Calibrating the multi-camera imaging system and geo-referencing the images are absolute prerequisites for all subsequent applications. Commercial cameras are inherently non-metric, that is, their sensor model is only approximately known. Since these cameras are not as rugged as photogrammetric cameras, the interior orientation also changes, due to temperature and pressure changes and aircraft vibration, resulting in large errors in 3D measurements. It is therefore necessary to calibrate the cameras frequently, at least whenever the system is newly installed. Geo-referencing the images is performed by the Applanix navigation system. Our new method enables a 3D reconstruction of ice sheet surface with high accuracy and unprecedented details, as it is demonstrated by examples from the Antarctic Peninsula, acquired by the IceBridge mission. Repeat digital imaging also provides data for determining surface elevation changes and velocities that are critical parameters for ice sheet models. Although these methods work well, there are known problems with satellite images and the traditional area-based matching, especially over rapidly changing outlet glaciers. To take full advantage of the high resolution, repeat stereo imaging we have developed a new method. The processing starts with the generation of a DEM from geo-referenced stereo images of the first time epoch. The next step is concerned with extracting and matching interest points in object space. Since an interest point moves its spatial position between two time epochs, such points are only radiometrically conjugate but not geometrically. In fact, the geometric displacement of two identical points, together with the time difference, renders velocities. We computed the evolution of the velocity field and surface topography on the floating tongue of the Jakobshavn glacier from historical stereo aerial photographs to illustrate the approach.

Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker Amundsen from the Polar 6 aircraft platform

NASA Astrophysics Data System (ADS)

Aliabadi, Amir A.; Thomas, Jennie L.; Herber, Andreas B.; Staebler, Ralf M.; Leaitch, W. Richard; Schulz, Hannes; Law, Kathy S.; Marelle, Louis; Burkart, Julia; Willis, Megan D.; Bozem, Heiko; Hoor, Peter M.; Köllner, Franziska; Schneider, Johannes; Levasseur, Maurice; Abbatt, Jonathan P. D.

2016-06-01

Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols) campaign, the plume dispersion and gas and particle emission factors of effluents originating from the Canadian Coast Guard icebreaker Amundsen operating near Resolute Bay, NU, Canada, were investigated. The Amundsen burned distillate fuel with 1.5 wt % sulfur. Emissions were studied via plume intercepts using the Polar 6 aircraft measurements, an analytical plume dispersion model, and using the FLEXPART-WRF Lagrangian particle dispersion model. The first plume intercept by the research aircraft was carried out on 19 July 2014 during the operation of the Amundsen in the open water. The second and third plume intercepts were carried out on 20 and 21 July 2014 when the Amundsen had reached the ice edge and operated under ice-breaking conditions. Typical of Arctic marine navigation, the engine load was low compared to cruising conditions for all of the plume intercepts. The measured species included mixing ratios of CO2, NOx, CO, SO2, particle number concentration (CN), refractory black carbon (rBC), and cloud condensation nuclei (CCN). The results were compared to similar experimental studies in mid-latitudes. Plume expansion rates (γ) were calculated using the analytical model and found to be γ = 0.75 ± 0.81, 0.93 ± 0.37, and 1.19 ± 0.39 for plumes 1, 2, and 3, respectively. These rates were smaller than prior studies conducted at mid-latitudes, likely due to polar boundary layer dynamics, including reduced turbulent mixing compared to mid-latitudes. All emission factors were in agreement with prior observations at low engine loads in mid-latitudes. Ice-breaking increased the NOx emission factor from EFNOx = 43.1 ± 15.2 to 71.6 ± 9.68 and 71.4 ± 4.14 g kg-diesel-1 for plumes 1, 2, and 3, likely due to changes in combustion temperatures. The CO emission factor was EFCO = 137 ± 120, 12.5 ± 3.70 and 8.13 ± 1.34 g kg-diesel-1 for plumes 1, 2, and 3. The rBC emission factor was EFrBC = 0.202 ± 0.052 and 0.202 ± 0.125 g kg-diesel-1 for plumes 1 and 2. The CN emission factor was reduced while ice-breaking from EFCN = 2.41 ± 0.47 to 0.45 ± 0.082 and 0.507 ± 0.037 × 1016 kg-diesel-1 for plumes 1, 2, and 3. At 0.6 % supersaturation, the CCN emission factor was comparable to observations in mid-latitudes at low engine loads with EFCCN = 3.03 ± 0.933, 1.39 ± 0.319, and 0.650 ± 0.136 × 1014 kg-diesel-1 for plumes 1, 2, and 3.

Spatio-temporal hotspots of satellite-tracked arctic foxes reveal a large detection range in a mammalian predator.

PubMed

Lai, Sandra; Bêty, Joël; Berteaux, Dominique

2015-01-01

The scale at which animals perceive their environment is a strong fitness determinant, yet few empirical estimates of animal detection ranges exist, especially in mammalian predators. Using daily Argos satellite tracking of 26 adult arctic foxes (Vulpes lagopus) during a single winter in the High Canadian Arctic, we investigated the detection range of arctic foxes by detecting hotspots of fox activity on the sea ice. While maintaining territories in the tundra, these solitary foragers occasionally used the sea ice where they sometimes formed spatio-temporal hotspots, likely scavenging on marine mammal carcasses. We detected 35 movements by 13 individuals forming five hotspots. Foxes often traveled more than 10 km, and up to 40 km, to reach hotspots, which lasted one-two weeks and could gather up to 12 individuals. The likelihood of a fox joining a hotspot was neither influenced by its distance from the hotspot nor by the distance of its home range to the coast. Observed traveling distances may indicate a high detection range in arctic foxes, and our results suggest their ability to detect food sources on the sea ice from their terrestrial home range. While revealing a wide knowledge gap regarding resource detection abilities in mammalian predators, our study provides estimates of detection range useful for interpreting and modeling animal movements. It also allows a better understanding of foraging behavior and navigation capacity in terrestrial predators.

Assessing Effects of Climate Change on Access to Ecosystem Services in Rural Alaska: Enhancing the Science through Community Engagement

NASA Astrophysics Data System (ADS)

Brinkman, T. J.; Cold, H.; Brown, D. N.; Brown, C.; Hollingsworth, T. N.; Verbyla, D.

2017-12-01

In Arctic-Boreal regions, studies quantifying the characteristics and prevalence of environmental disruptions to access to ecosystem services are lacking. Empirical investigations are needed to assess the vulnerability of rural communities to climate change. We integrated community-based local observation (9 Interior Alaska Communities), field-based ground measurements, and remote sensing data to: 1) identify and prioritize the relative importance of different environmental changes affecting access, 2) characterize the biophysical causes and mechanisms related to access, and 3) evaluate long-term (30 year) trends in the environment that are challenging access. Dynamic winter ice and snow conditions (e.g., dangerous ice travel; n =147) were the most commonly reported cause of disturbance to access, followed by changes in summer hydrology (e.g., river navigability; n = 77) and seasonal shifts in freeze/thaw cycles (n = 31). Supporting local observations, our remote-sensing analysis indicated a trend toward environmental conditions that hinder or disrupt traditional uses of ecosystem services. For example, we found that the window of safe travel on ice has narrowed by approximately 2 weeks since the 1980s. Shifts in travel have implications on the effectiveness of subsistence activities, such as winter trapping and spring waterfowl hunting. From a methods perspective, we implemented a study design that generated novel science while also addressing locally relevant issues. Our approach and findings highlight opportunities for connecting biophysical science with societal concerns.

SPINDLE: A 2-Stage Nuclear-Powered Cryobot for Ocean World Exploration

NASA Astrophysics Data System (ADS)

Stone, W.; Hogan, B.; Siegel, V. L.; Howe, T.; Howe, S.; Harman, J.; Richmond, K.; Flesher, C.; Clark, E.; Lelievre, S.; Moor, J.; Rothhammer, B.

2016-12-01

SPINDLE (Sub-glacial Polar Ice Navigation, Descent, and Lake Exploration) is a 2-stage autonomous vehicle system consisting of a robotic ice-penetrating carrier vehicle (cryobot) and a marsupial, hovering autonomous underwater vehicle (HAUV). The cryobot will descend through an ice body into a sub-ice aqueous environment and deploy the HAUV to conduct long range reconnaissance, life search, and sample collection. The HAUV will return to, and auto-dock with, the cryobot at the conclusion of the mission for subsequent data uplink and sample return to the surface. The SPINDLE cryobot has been currently designed for a 1.5 kilometer penetration through a terrestrial ice sheet and the HAUV has been designed for persistent exploration and science presence in for deployments up to a kilometer radius from the cryobot. Importantly, the cryobot is bi-directional and vertically controllable both in an ice sheet as well as following breakthrough into a subglacial water cavity / ocean. The vehicle has been designed for long-duration persistent science in subglacial cavities and to allow for subsequent return-to-surface at a much later date or subsequent season. Engineering designs for the current SPINDLE cryobot will be presented in addition to current designs for autonomous rendezvous, docking, and storing of the HAUV system into the cryobot for subsequent recovery of the entire system to the surface. Taken to completion in a three-phase program, SPINDLE will deliver an integrated and field-tested system that will be directly transferable into a Flagship-class mission to either the hypothesized shallow lakes of Europa, the sub-surface ocean of Ganymede, or the geyser/plume sources on both Europa and Enceladus. We present the results of several parallel laboratory investigations into advanced power transmission systems (laser, high voltage) as well as onboard systems that enable the SPINDLE vehicle to access any subglacial lake on earth while using non-nuclear surrogate, surface-based power systems and accounting for full re-freeze of the hole behind the cryobot. We additionally present new designs for a compatible nuclear drop-in power source and include preliminary design results for both radio-thermal and compact fission power plant designs that would be used for actual ocean world missions.

Making sense of Arctic maritime traffic using the Polar Operational Limits Assessment Risk Indexing System (POLARIS)

NASA Astrophysics Data System (ADS)

Stoddard, M. A.; Etienne, L.; Fournier, M.; Pelot, R.; Beveridge, L.

2016-04-01

Maritime traffic volume in the Arctic is growing for several reasons: climate change is resulting in less ice in extent, duration, and thickness; economic drivers are inducing growth in resource extraction traffic, community size (affecting resupply) and adventure tourism. This dynamic situation, coupled with harsh weather, variable operating conditions, remoteness, and lack of straightforward emergency response options, demand robust risk management processes. The requirements for risk management for polar ship operations are specified in the new International Maritime Organization (IMO) International Code for Ships Operating in Polar Waters (Polar Code). The goal of the Polar Code is to provide for safe ship operations and protection of the polar environment by addressing the risk present in polar waters. Risk management is supported by evidence-based models, including threat identification (types and frequency of hazards), exposure levels, and receptor characterization. Most of the information used to perform risk management in polar waters is attained in-situ, but increasingly is being augmented with open-access remote sensing information. In this paper we focus on the use of open-access historical ice charts as an integral part of northern navigation, especially for route planning and evaluation.

Applications of ERTS data to resource surveys of Alaska

NASA Technical Reports Server (NTRS)

Belon, A. E.; Miller, J. M.

1974-01-01

ERTS data affords a unique opportunity to perform urgently needed resource surveys and land use planning at a critical juncture in the history of Alaska's social and economic development. The available facilities for photographic, optical and digital processing of ERTS data are described, along with the interpretive techniques which have been developed. Examples of the applications of these facilities and techniques are given for three environmental disciplines: vegetation mapping for potential archeological sites; marine and sea ice surveys on the Alaskan continental shelf for the determination of surface circulation and sedimentation patterns and their effects on navigation, pollution assessment, fisheries, location of habors and construction of off-shore structures; snow surveys for inventories of water resources and flood potential in Alaska watersheds.

Segmentation of left atrial intracardiac ultrasound images for image guided cardiac ablation therapy

NASA Astrophysics Data System (ADS)

Rettmann, M. E.; Stephens, T.; Holmes, D. R.; Linte, C.; Packer, D. L.; Robb, R. A.

2013-03-01

Intracardiac echocardiography (ICE), a technique in which structures of the heart are imaged using a catheter navigated inside the cardiac chambers, is an important imaging technique for guidance in cardiac ablation therapy. Automatic segmentation of these images is valuable for guidance and targeting of treatment sites. In this paper, we describe an approach to segment ICE images by generating an empirical model of blood pool and tissue intensities. Normal, Weibull, Gamma, and Generalized Extreme Value (GEV) distributions are fit to histograms of tissue and blood pool pixels from a series of ICE scans. A total of 40 images from 4 separate studies were evaluated. The model was trained and tested using two approaches. In the first approach, the model was trained on all images from 3 studies and subsequently tested on the 40 images from the 4th study. This procedure was repeated 4 times using a leave-one-out strategy. This is termed the between-subjects approach. In the second approach, the model was trained on 10 randomly selected images from a single study and tested on the remaining 30 images in that study. This is termed the within-subjects approach. For both approaches, the model was used to automatically segment ICE images into blood and tissue regions. Each pixel is classified using the Generalized Liklihood Ratio Test across neighborhood sizes ranging from 1 to 49. Automatic segmentation results were compared against manual segmentations for all images. In the between-subjects approach, the GEV distribution using a neighborhood size of 17 was found to be the most accurate with a misclassification rate of approximately 17%. In the within-subjects approach, the GEV distribution using a neighborhood size of 19 was found to be the most accurate with a misclassification rate of approximately 15%. As expected, the majority of misclassified pixels were located near the boundaries between tissue and blood pool regions for both methods.

Efficacy of a novel IGS system in atrial septal defect repair

NASA Astrophysics Data System (ADS)

Mefleh, Fuad N.; Baker, G. Hamilton; Kwartowitz, David M.

2013-03-01

Congenital heart disease occurs in 107.6 out of 10,000 live births, with Atrial Septal Defects (ASD) accounting for 10% of these conditions. Historically, ASDs were treated with open heart surgery using cardiopulmonary bypass, allowing a patch to be sewn over the defect. In 1976, King et al. demonstrated use of a transcatheter occlusion procedure, thus reducing the invasiveness of ASD repair. Localization during these catheter based procedures traditionally has relied on bi-plane fluoroscopy; more recently trans-esophageal echocardiography (TEE) and intra-cardiac echocardiography (ICE) have been used to navigate these procedures. Although there is a high success rate using the transcatheter occlusion procedure, fluoroscopy poses radiation dose risk to both patient and clinician. The impact of this dose to the patients is important as many of those undergoing this procedure are children, who have an increased risk associated with radiation exposure. Their longer life expectancy than adults provides a larger window of opportunity for expressing the damaging effects of ionizing radiation. In addition, epidemiologic studies of exposed populations have demonstrated that children are considerably more sensitive to the carcinogenic effects radiation. Image-guided surgery (IGS) uses pre-operative and intra-operative images to guide surgery or an interventional procedure. Central to every IGS system is a software application capable of processing and displaying patient images, registration between multiple coordinate systems, and interfacing with a tool tracking system. We have developed a novel image-guided surgery framework called Kit for Navigation by Image Focused Exploration (KNIFE). In this work we assess the efficacy of this image-guided navigation system for ASD repair using a series of mock clinical experiments designed to simulate ASD repair device deployment.

Multi-centennial Record of Labrador Sea Primary Productivity and Sea-Ice Variability Archived in Coralline Algal Ba/Ca

NASA Astrophysics Data System (ADS)

Chan, Phoebe; Halfar, Jochen; Adey, Walter; Hetzinger, Steffen; Zack, Thomas; Moore, Kent; Wortmann, Ulrich; Williams, Branwen; Hou, Alicia

2017-04-01

Arctic sea-ice thickness and concentration have dropped by approximately 9% per decade since 1978. Concurrent with this sea-ice decline is an increase in rates of phytoplankton productivity, driven by shoaling of the mixed layer and enhanced transmittance of solar radiation into the surface ocean. This has recently been confirmed by phytoplankton studies in Arctic and Subarctic basins that have revealed earlier timing, prolonged duration, and increased primary productivity of the spring phytoplankton bloom. However, difficulties of navigating in remote ice-laden waters and harsh polar climates have often resulted in short and incomplete records of in-situ plankton abundance in the northwestern Labrador Sea. Alternatively, information of past ocean productivity may be gained through the study of trace nutrient distributions in the surface water column. Investigations of dissolved barium (Ba) concentrations in the Arctic reveal significant depletions of Ba in surface seawaters due to biological scavenging during the spring phytoplankton bloom. Here we apply a barium-to-calcium (Ba/Ca) and carbon isotope (δ13C) multiproxy approach to long-lived crustose coralline algae in order to reconstruct an annually-resolved multi-centennial record of Labrador Sea productivity related to sea-ice variability in Labrador, Canada that extends well into the Little Ice Age (LIA; 1646 AD). The crustose coralline alga Clathromorphum compactum is a shallow marine calcareous plant that is abundant along the eastern Canadian coastline, and produces annual growth increments which allow for the precise calendar dating and geochemical sampling of hard tissue. Algal Ba/Ca ratios can serve as a promising new proxy for surface water productivity, demonstrating a close correspondence to δ13C that does not suffer from the anthropogenically-induced carbon isotope decline (ex. Suess Effect) beginning in the 1960s. Coralline algal Ba/Ca demonstrates statistically significant correlations to both observational and proxy records of sea-ice extent and transport variability, and shows a persistent pattern of covariability that is broadly consistent with the timing and phasing of the Atlantic Multidecadal Oscillation (AMO). Lower algal Ba/Ca values are interpreted as increased productivity (via biological scavenging) coinciding with warming sea surface temperatures and melting of sea-ice, and vice versa. This relationship is further supported by negative correlations between algal Ba/Ca and spatially averaged chlorophyll α concentrations determined from Sea-Viewing Wide Field-of-View Sensor (SeaWiFS; 1998 - 2009) ocean colour data. Extended comparisons to a multi-centennial tree-ring proxy AMO index demonstrates more frequent positive Ba/Ca excursions (indicating reduced productivity) associated with AMO cool phases during the Little Ice Age, followed by a step-wise decline in Ba/Ca (indicating increasing productivity) from 1910 to present levels - unprecedented in the last 365 years. Our multi-centennial record of coralline algal Ba/Ca in the Subarctic northwest Atlantic demonstrates a long-term increasing trend in primary productivity that is in agreement with recent satellite-based productivity in the Arctic Ocean. This ongoing increase in phytoplankton productivity is expected to fundamentally alter marine biodiversity and trophic dynamics as warming and freshening of the surface layer is projected to intensify over the coming century.

Autonomous Rover for Polar GPR Surveys

NASA Astrophysics Data System (ADS)

Ray, L.; Lever, J. H.; Courville, Z.; Walker, B.; Arcone, S. A.

2015-12-01

We deployed Yeti, an 80-kg, 4WD battery-powered rover to conduct ground-penetrating radar (GPR) surveys over crevasse-ridden ice sheets in Antarctica and Greenland. The rover navigated using GPS waypoint following and had 3 - 4 hr endurance at 5 km/hr while towing 60 - 70 kg of GPR equipment. Yeti's low ground pressure allowed it to cross thinly bridged crevasses without interrupting a survey. In Feb - Mar 2014, Yeti executed 23 autonomous GPR surveys covering 94 km of terrain on the ice transition to the main ice sheet in northwest Greenland. This was the first robotic effort directly to support manual crevasse surveys to map a safe route for vehicle travel, in this case a resupply traverse to Summit Station. Yeti towed a radar controller, 400 MHz antenna, GPS receiver and battery pack. Radar scan rate was 16 scans/m and pulse timing allowed good spatial resolution to about 20-m depth. The resulting data allowed us to map hundreds of subsurface crevasses and provide the results nightly to the manual survey team to compliment its efforts. We met our objectives: (a) to enhance operational efficiency of the concurrent manual surveys, and (b) to create a geo-referenced database of crevasse signatures to validate aerial- and satellite-based crevasse-mapping platforms. In Oct - Nov 2014, we deployed Yeti in Antarctica to conduct systematic GPR surveys across a crevasse-ridden section of the shear margin between the Ross and McMurdo ice shelves and thereby gain insight into its state of fracture and long-term stability. Yeti flawlessly executed a total of 613 km of autonomous GPR surveys at temperatures as low as - 33ºC. The rover towed a a radar controlling a 400 MHz and a 200 MHz antenna, the latter added to profile 160 m through the ice sheet. The main survey grid covered 5.7 km x 5.0 km, with survey lines at 50-m spacing oriented west-east across the Shear Zone (575 km total length). Yeti's tracks normally deviated only 1 - 2 m from a straight line between the two end waypoints. Interpreted features include crevasses up to 16 m wide with snowbridges up to 10 m thick and at least the upper 16 m of stratified marine basal ice. These autonomous GPR surveys could not have been conducted safely using manual methods owing to the numerous, thinly bridged crevasses. Such systematic, repetitious measurements can enhance other Polar research projects.

Efficient transfer of weather information to the pilot in flight

NASA Technical Reports Server (NTRS)

Mcfarland, R. H.

1982-01-01

Efficient methods for providing weather information to the pilot in flight are summarized. Use of discrete communications channels in the aeronautical, VHF band or subcarriers in the VOR navigation band are considered the best possibilities. Data rates can be provided such that inputs to the ground based transmitters from 2400 band telephone lines are easily accommodated together with additional data. The crucial weather data considered for uplinking are identified as radar reflectivity patterns relating to precipitation, spherics data, hourly sequences, nowcasts, forecasts, cloud top heights with freezing and icing conditions, the critical weather map and satellite maps. NEXRAD, the ground based, Doppler weather radar which will produce an improved weather product also encourages use of an uplink to fully utilize its capability to improve air safety.

Global navigation satellite sounding of the atmosphere and GNSS altimetry : prospects for geosciences

NASA Technical Reports Server (NTRS)

Yunck, Tom P.; Hajj, George A.

2003-01-01

The vast illuminating power of the Global Positioning System (GPS), which transformed space geodesy in the 199Os, is now serving to probe the earth's fluid envelope in unique ways. Three distinct techniques have emerged: ground-based sensing of the integrated atmospheric moisture; space-based profiling of atmospheric refractivity, pressure, temperature, moisture, and other properties by active limb sounding; and surface (ocean and ice) altimetry and scatterometry with reflected signals detected from space. Ground-based GPS moisture sensing is already in provisional use for numerical weather prediction. Limb sounding, while less mature, offers a bevy of attractions, including high accuracy, stability, and vertical resolution; all-weather operation; and exceptionally low cost. GPS bistatic radar, r 'reflectometry,' is the least advanced but shows promise for a number of niche applications.

Interannual Variability of Water Ice Clouds at Gale Crater

NASA Astrophysics Data System (ADS)

Martinez, G.; Giuranna, M.; McConnochie, T. H.; Tamppari, L.; Smith, M. D.; Vicente-Retortillo, Á.; Renno, N. O.; Kloos, J. L.; Moores, J. E.; Guzewich, S.

2017-12-01

The Aphelion Cloud Belt (ACB) is a water ice cloud band that encircles the planet longitudinally at latitudes ranging from about 10°S to 30°N during the northern spring and summer (aphelion season). The ACB has been studied extensively using satellite observations over the last two decades [1], showing little interannual variability from MY 24 to 34. The Mars Science Laboratory (MSL) mission has completed more than 1750 sols of measurements at Gale crater (4.5°S), from Ls 155° in MY 31 to Ls 33° in MY 34. Interestingly, MSL results from various instruments indicate that the ACB produces significant interannual variability at Gale crater during the aphelion season. In particular, near-noon retrievals of water ice opacity by the ChemCam instrument indicate an increase in water ice opacity up to 50% from MY 32 to 33 [2], further supported by analysis of UV [3] and ground temperature [4] data taken by the Rover Environmental Monitoring Station during MY 32 and 33. A weaker ( 5%) increase in water ice opacity in MY 33 relative to MY 32 was also observed from images taken during afternoon hours by the rover's Navigation Cameras [5]. We are analyzing simultaneous and noncontemporary satellite observations at the location of Gale made by the Planetary Fourier Spectrometer [6], Mars Climate Sounder, Thermal Emission Imaging System and Thermal Emission Spectrometer to shed light on the nature of the interannual variability of the ACB at Gale, and to locally understand the relation between the ACB and the water cycle. References:[1] Smith, M.D. (2008), Spacecraft observations of the martian atmosphere, Annu. Rev. Earth Planet. Sci. 36. [2] McConnochie, T. H., et al. (2017), Retrieval of Water Vapor Column Abundance and Aerosol Properties from ChemCam Passive Sky Spectroscopy, Icarus (submitted). [3] Vicente-Retortillo, Á., et al. (2017), Determination of dust aerosol particle size at Gale Crater using REMS UVS and Mastcam measurements, GRL, 44. [4] Vasavada, A.R. et al. (2017), Thermophysical properties along Curiosity's traverse in Gale crater, Mars, Icarus 284. [5] Kloos, J. L., and J. E. Moores (2017), Inter-Annual and Diurnal Variability in Clouds Observed from MSL Over Two Martian Years, LPSC, 48. [6] Giuranna, M. et al. (2016), 12 years of atmospheric monitoring by the Planetary Fourier Spectrometer onboard Mars Express, EGU.

The GNSS Reflectometry Response to the Ocean Surface

NASA Astrophysics Data System (ADS)

Chang, Paul; Jelenak, Zorana; Soisuvarn, Seubson; Said, Faozi

2016-04-01

Global Navigation Satellite System - Reflectometry (GNSS-R) exploits signals of opportunity from the Global Navigation Satellite System (GNSS). GNSS transmitters continuously transmit navigation signals at L-band toward the earth's surface. The scattered power reflected off the earth's surface can be sensed by specially designed GNSS-R receivers. The reflected signal can then be used to glean information about the surface of the earth, such as ocean surface roughness, snow depth, sea ice extent, and soil moisture. The use of GNSS-R for ocean wind retrievals was first demonstrated from aircraft. On July 8 2014, the TechDemoSat-1 satellite (TDS-1) was launched by Surrey Satellite Technology, Ltd as a technology risk reduction mission into sun-synchronous orbit. This paper investigates the GNSS-R measurements collected by the Space GNSS Receiver-Remote Sensing Instrument (SGR-ReSI) on board the TDS-1 satellite. The sensitivity of the SGR-ReSI measurements to the ocean surface winds and waves are characterized. The effects of sea surface temperature, wind direction, and rain are also investigated. The SGR-ReSI measurements exhibited sensitivity through the entire range of wind speeds sampled in this dataset, up to 35 m/s. A significant dependence on the larger waves was observed for winds < 6 m/s. Additionally, an interesting dependence on SST was observed where the slope of the SGR-ReSI measurements is positive for winds < 5 m/s and reverses for winds > 5 m/s. There appeared to be very little wind direction signal, and investigation of the rain impacts found no apparent sensitivity in the data. These results are shown through the analysis of global statistics and examination of a few case studies. This released SGR-ReSI dataset provided the first opportunity to comprehensively investigate the sensitivity of satellite-based GNSS-R measurements to various ocean surface parameters. The upcoming NASA's Cyclone Global Navigation Satellite System (CYGNSS) satellite constellation will utilize a similar receiver to SGI-ReSI and thus this data provides valuable pre-launch knowledge for the CYGNSS mission.

Real-time visual mosaicking and navigation on the seafloor

NASA Astrophysics Data System (ADS)

Richmond, Kristof

Remote robotic exploration holds vast potential for gaining knowledge about extreme environments accessible to humans only with great difficulty. Robotic explorers have been sent to other solar system bodies, and on this planet into inaccessible areas such as caves and volcanoes. In fact, the largest unexplored land area on earth lies hidden in the airless cold and intense pressure of the ocean depths. Exploration in the oceans is further hindered by water's high absorption of electromagnetic radiation, which both inhibits remote sensing from the surface, and limits communications with the bottom. The Earth's oceans thus provide an attractive target for developing remote exploration capabilities. As a result, numerous robotic vehicles now routinely survey this environment, from remotely operated vehicles piloted over tethers from the surface to torpedo-shaped autonomous underwater vehicles surveying the mid-waters. However, these vehicles are limited in their ability to navigate relative to their environment. This limits their ability to return to sites with precision without the use of external navigation aids, and to maneuver near and interact with objects autonomously in the water and on the sea floor. The enabling of environment-relative positioning on fully autonomous underwater vehicles will greatly extend their power and utility for remote exploration in the furthest reaches of the Earth's waters---even under ice and under ground---and eventually in extraterrestrial liquid environments such as Europa's oceans. This thesis presents an operational, fielded system for visual navigation of underwater robotic vehicles in unexplored areas of the seafloor. The system does not depend on external sensing systems, using only instruments on board the vehicle. As an area is explored, a camera is used to capture images and a composite view, or visual mosaic, of the ocean bottom is created in real time. Side-to-side visual registration of images is combined with dead-reckoned navigation information in a framework allowing the creation and updating of large, locally consistent mosaics. These mosaics are used as maps in which the vehicle can navigate and localize itself with respect to points in the environment. The system achieves real-time performance in several ways. First, wherever possible, direct sensing of motion parameters is used in place of extracting them from visual data. Second, trajectories are chosen to enable a hierarchical search for side-to-side links which limits the amount of searching performed without sacrificing robustness. Finally, the map estimation is formulated as a sparse, linear information filter allowing rapid updating of large maps. The visual navigation enabled by the work in this thesis represents a new capability for remotely operated vehicles, and an enabling capability for a new generation of autonomous vehicles which explore and interact with remote, unknown and unstructured underwater environments. The real-time mosaic can be used on current tethered vehicles to create pilot aids and provide a vehicle user with situational awareness of the local environment and the position of the vehicle within it. For autonomous vehicles, the visual navigation system enables precise environment-relative positioning and mapping, without requiring external navigation systems, opening the way for ever-expanding autonomous exploration capabilities. The utility of this system was demonstrated in the field at sites of scientific interest using the ROVs Ventana and Tiburon operated by the Monterey Bay Aquarium Research Institute. A number of sites in and around Monterey Bay, California were mosaicked using the system, culminating in a complete imaging of the wreck site of the USS Macon , where real-time visual mosaics containing thousands of images were generated while navigating using only sensor systems on board the vehicle.

Glacial isostatic adjustment using GNSS permanent stations and GIA modelling tools

NASA Astrophysics Data System (ADS)

Kollo, Karin; Spada, Giorgio; Vermeer, Martin

2013-04-01

Glacial Isostatic Adjustment (GIA) affects the Earth's mantle in areas which were once ice covered and the process is still ongoing. In this contribution we focus on GIA processes in Fennoscandian and North American uplift regions. In this contribution we use horizontal and vertical uplift rates from Global Navigation Satellite System (GNSS) permanent stations. For Fennoscandia the BIFROST dataset (Lidberg, 2010) and North America the dataset from Sella, 2007 were used respectively. We perform GIA modelling with the SELEN program (Spada and Stocchi, 2007) and we vary ice model parameters in space in order to find ice model which suits best with uplift values obtained from GNSS time series analysis. In the GIA modelling, the ice models ICE-5G (Peltier, 2004) and the ice model denoted as ANU05 ((Fleming and Lambeck, 2004) and references therein) were used. As reference, the velocity field from GNSS permanent station time series was used for both target areas. Firstly the sensitivity to the harmonic degree was tested in order to reduce the computation time. In the test, nominal viscosity values and pre-defined lithosphere thicknesses models were used, varying maximum harmonic degree values. Main criteria for choosing the suitable harmonic degree was chi-square fit - if the error measure does not differ more than 10%, then one might use as well lower harmonic degree value. From this test, maximum harmonic degree of 72 was chosen to perform calculations, as the larger value did not significantly modify the results obtained, as well the computational time for observations was kept reasonable. Secondly the GIA computations were performed to find the model, which could fit with highest probability to the GNSS-based velocity field in the target areas. In order to find best fitting Earth viscosity parameters, different viscosity profiles for the Earth models were tested and their impact on horizontal and vertical velocity rates from GIA modelling was studied. For every tested model the chi-square misfit for horizontal, vertical and three-dimensional velocity rates from the reference model was found (Milne, 2001). Finally, the best fitting models from GIA modelling were compared with rates obtained from GNSS data. Keywords: Fennoscandia, North America, land uplift, glacial isostatic adjustment, visco-elastic modelling, BIFROST. References Lidberg, M., Johannson, J., Scherneck, H.-G. and Milne, G. (2010). Recent results based on continuous GPS observations of the GIA process in Fennoscandia from BIFROST. Journal of Geodynamics, 50. pp. 8-18. Sella, G. F., Stein, S., Dixon, T. H., Craymer, M., James, T. S., Mazotti, S. and Dokka, R. K. (2007). Observations of glacial isostatic adjustment in "stable" North America with GPS. Geophysical Research Letters, 34, L02306. Spada, G., Stocchi, P. (2007). SELEN: A Fortran 90 program for solving the "sea-level equation". Computers & Geosciences, 33:538-562, 2007. Peltier, W. R. (2004). Global glacial isostasy and the surface of the ice-age Earth: The Ice-5G (VM2) model and GRACE. Annu. Rev. Earth Planet. Sci., 32:111-149, 2004. Fleming, K. and Lambeck, K. (2004). Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models. Quaternary Science Reviews 23 (2004), pp. 1053-1077. Milne, G. A. and Davis, J. L. and Mitrovica, J. X. and Scherneck, H.-G. and Johansson, J. M. and Vermeer, M. and Koivula, H. (2001). Space-geodetic constraints on glacial isostatic adjustment in Fennoscandia. Science 291 (2001), pp. 2381-2385.

Magnetic Dinner Salads: The Role of Biogenic Magnetite in Cryopreservation for Common Food Plants

NASA Astrophysics Data System (ADS)

Chaffee, T. M.; Kirschvink, J. L.; Kobayashi, A. K.

2015-12-01

Biogenically-precipitated magnetite has been found in organisms ranging from Bacteria, single-celled protists, and many of the animal phyla, where its major function is navigation and magnetoreception. To date there is but a single report of biogenic magnetite in plants (essentially, magnetoferritin), and that is in common grass (Festuca species, from Gajdardziska-Josifovska et. al. doi:10.1127/0935-1221/2001/0013/0863). Recent developments in cryopreservation suggest that ~ 1 mT, ~ 10 Hz oscillating magnetic fields can drastically reduce ice nucleation during freezing, promote supercooling, and minimize cellular damage in living tissues (e.g., Kaku et al., doi: 10.1016/j.cryobiol.2012.02.001). Kobayashi & Kirschvink (2014, doi:10.1016/j.cryobiol.2013.12.002) suggest that biogenic magnetite crystals could be the nucleating site for damaging ice crystals, and that they would be driven magneto-mechanically to rotate in those oscillating fields which could inhibit the ice crystal nucleation process. This prompted our investigation into the magnetite content of ordinary fruit and vegetable food products, as knowledge of the natural levels of biogenic magnetite in the human food supply could guide the selection of which foods might work for this type of cryopreservation. Our study involved a range of common foods including avocados, bananas, garlic, and apples. Samples were prepared in a clean lab environment kept free of contaminant particles, and subjected to a variety of standard rock-magnetic tests including IRM and ARM acquisition, and the corresponding Af demagnetization, on a standard 2G™ SRM. Results are consistent with moderately interacting single-domain magnetite (see figure), with moderate inter-particle interaction effects. Typical magnetite concentrations in these samples are in the range of .1 to 1 ng/g for room temperature samples, increasing to the range of 1-10 ng/g when measured frozen (to inhibit thermal rotation of small particles and clumps). If these are distributed as fine, single-domain particles they would constitute the largest mineral surface area in the tissues, (aside from amorphous silica phytoliths), and are therefore likely the site of ice crystal nucleation.

Radar research at the University of Kansas

NASA Astrophysics Data System (ADS)

Blunt, Shannon D.; Allen, Christopher; Arnold, Emily; Hale, Richard; Hui, Rongqing; Keshmiri, Shahriar; Leuschen, Carlton; Li, Jilu; Paden, John; Rodriguez-Morales, Fernando; Salandrino, Alessandro; Stiles, James

2017-05-01

Radar research has been synonymous with the University of Kansas (KU) for over half a century. As part of this special session organized to highlight significant radar programs in academia, this paper surveys recent and ongoing work at KU. This work encompasses a wide breadth of sensing applications including the remote sensing of ice sheets, autonomous navigation methods for unmanned aerial vehicles (UAVs), novel laser radar capabilities, detection of highenergy cosmic rays using bistatic radar, different forms of waveform diversity such as MIMO radar and pulse agility, and various radar-embedded communication methods. The results of these efforts impact our understanding of the changing nature of the environment, address the proliferation of unmanned systems in the US airspace, realize new sensing modalities enabled by the joint consideration of electromagnetics and signal processing, and greater facilitate radar operation in an increasingly congested and contested spectrum.

Bio-inspired Computing for Robots

NASA Technical Reports Server (NTRS)

Laufenberg, Larry

2003-01-01

Living creatures may provide algorithms to enable active sensing/control systems in robots. Active sensing could enable planetary rovers to feel their way in unknown environments. The surface of Jupiter's moon Europa consists of fractured ice over a liquid sea that may contain microbes similar to those on Earth. To explore such extreme environments, NASA needs robots that autonomously survive, navigate, and gather scientific data. They will be too far away for guidance from Earth. They must sense their environment and control their own movements to avoid obstacles or investigate a science opportunity. To meet this challenge, CICT's Information Technology Strategic Research (ITSR) Project is funding neurobiologists at NASA's Jet Propulsion Laboratory (JPL) and selected universities to search for biologically inspired algorithms that enable robust active sensing and control for exploratory robots. Sources for these algorithms are living creatures, including rats and electric fish.

Orbit Determination Covariance Analysis for the Europa Clipper Mission

NASA Technical Reports Server (NTRS)

Ionasescu, Rodica; Martin-Mur, Tomas; Valerino, Powtawche; Criddle, Kevin; Buffington, Brent; McElrath, Timothy

2014-01-01

A new Jovian satellite tour is proposed by NASA, which would include numerous flybys of the moon Europa, and would explore its potential habitability by characterizing the existence of any water within and beneath Europa's ice shell. This paper describes the results of a covariance study that was undertaken on a sample tour to assess the navigational challenges and capabilities of such a mission from an orbit determination (OD) point of view, and to help establish a delta V budget for the maneuvers needed to keep the spacecraft on the reference trajectory. Additional parametric variations from the baseline case were also investigated. The success of the Europa Clipper mission will depend on the science measurements that it will enable. Meeting the requirements of the instruments onboard the spacecraft is an integral part of this analysis.

A Web-Based Toolkit to Provide Evidence-Based Resources About Crystal Methamphetamine for the Australian Community: Collaborative Development of Cracks in the Ice.

PubMed

Champion, Katrina Elizabeth; Chapman, Cath; Newton, Nicola Clare; Brierley, Mary-Ellen; Stapinski, Lexine; Kay-Lambkin, Frances; Nagle, Jack; Teesson, Maree

2018-03-20

The use of crystal methamphetamine (ice) and the associated harms for individuals, families, and communities across Australia has been the subject of growing concern in recent years. The provision of easily accessible, evidence-based, and up-to-date information and resources about crystal methamphetamine for the community is a critical component of an effective public health response. This paper aims to describe the codevelopment process of the Web-based Cracks in the Ice Community Toolkit, which was developed to improve access to evidence-based information and resources about crystal methamphetamine for the Australian community. Development of the Cracks in the Ice Community Toolkit was conducted in collaboration with community members across Australia and with experts working in the addiction field. The iterative process involved the following: (1) consultation with end users, including community members, crystal methamphetamine users, families and friends of someone using crystal methamphetamine, health professionals, and teachers (n=451) via a cross-sectional Web-based survey to understand information needs; (2) content and Web development; and (3) user testing of a beta version of the Web-based toolkit among end users (n=41) and experts (n=10) to evaluate the toolkit's acceptability, relevance, and appeal. Initial end user consultation indicated that the most commonly endorsed reasons for visiting a website about crystal methamphetamine were "to get information for myself" (185/451, 41.0%) and "to find out how to help a friend or a family member" (136/451, 30.2%). Community consultation also revealed the need for simple information about crystal methamphetamine, including what it is, its effects, and when and where to seek help or support. Feedback on a beta version of the toolkit was positive in terms of content, readability, layout, look, and feel. Commonly identified areas for improvement related to increasing the level of engagement and personal connection, improving the ease of navigation, and balancing a "low prevalence of use, yet high impact" message. A total of 9138 users visited the website in the 3 months immediately post launch, and over 25,000 hard-copy Cracks in the Ice booklets and flyers were distributed across Australia. Of these resources, 60.93% (15,525/25,480) were distributed to relevant organizations and mailing list subscribers, and 39.07% (9955/25,480) were ordered directly by individuals, services, and community groups via the Cracks in the Ice website. The codevelopment process resulted in an engaging Web-based resource for the Australian community to access up-to-date and evidence-based resources about crystal methamphetamine. The Cracks in the Ice Community Toolkit provides much-needed information and support for individuals, families, and communities. ©Katrina Elizabeth Champion, Cath Chapman, Nicola Clare Newton, Mary-Ellen Brierley, Lexine Stapinski, Frances Kay-Lambkin, Jack Nagle, Maree Teesson. Originally published in JMIR Mental Health (http://mental.jmir.org), 20.03.2018.

Observation of Drifting Icebergs and Sea Ice from Space by TerraSAR-X and TanDEM-X

NASA Astrophysics Data System (ADS)

Won, Joong-Sun

2017-04-01

Detection and monitoring drifting icebergs and sea ice is of interest across wide range of Arctic and Antarctic coastal studies such as security of navigation, climatic impact, geological impact, etc. It is not easy to discriminate drifting ices from stationary ones, and to measure their drifting speeds. There is a potential to use space-borne SAR for this purpose, but it is difficult to precisely measure because the drift velocity is usually very slow. In this study, we investigate two approaches for discriminating drifting ices on the sea from surrounding static ones and for measuring their range velocity. The first method is to utilize the quad-pol TerraSAR-X which adopts dual receive antenna (DRA), and the second one is to examine the potential use of TanDEM-X bistatic along-track interferometry (ATI). To utilize DRA mode quad-pol SAR as ATI, it is necessary to remove the phase difference of scattering centers between transmitted H- and V-pol signals. By assume that the individual scattering center of returned signal does not change for a few inter-pulse periods, it is possible to measure the Doppler frequency induced by motion through measuring slow-time (or azimuth time) Doppler phase derivative of co-pol or cross-pol pairs. Results applied to TerraSAR-X quad-pol data over the Cape Columbia in the Arctic Ocean are to be presented and discussed. It was successful to detect and measure drift sea ice that was flowing away from the antenna with a velocity of about 0.37 m/s (or 1.4 km/h) to 0.67 m/s (or 2.4 km/h) while neighboring ones were static. A more sophisticated approach would be a bistatic ATI which exploits a long along-track baseline for observation of slowly moving ground objects. TanDEM-X bistatic ATI pairs are examined, which were acquired at an Antarctic coast. The ATI interferograms show an innovative capability of TanDEM-X/TerraSAR-X constellation. An along-track baseline of a few hundred meters is superior to a few meter baseline of DRA mode ATI system. However, topographic phase is inevitably mixed with Doppler phase associated with target motion because of a non-zero perpendicular baseline (or effective baseline). Thus it is necessary to separate target motion components from topographic components that are unknown for icebergs. Here we examine characteristics of the topographic phase of drift sea ice in the bistatic ATI interferograms, and discuss a detouring approach to quick detection of drifting icebergs by TanDEM-X bistatic ATI. The results demonstrate that it would be efficient to detect drifting icebergs and sea ice from space by utilizing high resolution SAR systems while the precise measurement of the drifting speeds requires further studies.

TopoGreenland: crustal structure in central-eastern Greenland along a new refraction profile

NASA Astrophysics Data System (ADS)

Shulgin, Alexey; Thybo, Hans; Field Team TopoGreenland

2013-04-01

We present the seismic structure in the interior of Greenland based on the first measurements by the seismic refraction/wide angle reflection method. Previous seismic surveys have only been carried out offshore and near the coast of Greenland, where the crustal structure is affected by oceanic break-up and may not be representative of the interior of the island. Acquisition of geophysical data in onshore Greenland is logistically complicated by the presence of an up to 3.4 km thick ice sheet, permanently covering most of the land mass. The seismic data was acquired by a team of six people during a two-month long experiment in summer of 2011 on the ice cap in the interior of central-eastern Greenland. The EW-trending profile extends 310 km inland from the approximate edge of the stable ice cap near Scoresby Sund across the center of the ice cap. The planned extension of the profile by use of OBSs and air gun shooting in Scoresbysund Fjord to the east coast of Greenland was unfortunately canceled, because navigation was prevented by ice drift. 350 Reftek Texan receivers recorded high-quality seismic data from 8 equidistant shots along the profile. Explosive charge sizes were 1 ton at the ends and ca. 500 kg along the profile, loaded with about 125 kg at 35-85 m depth in individual boreholes. Two-dimensional velocity model based on tomographic inversion and forward ray tracing modeling shows a decrease of crustal thickness from 47 km below the center of Greenland in the western part to 40 km in the eastern part of the profile. Earlier studies show that crustal thickness further decreases eastward to ca. 30 km below the fjord system, but details of the changes are unknown. Relatively high lower crustal velocities (Vp 6.8 - 7.3) in the western part of the TopoGreenland profile may indicate past collision tectonics or may be related or to the passage of the Iceland mantle plume. The origin of the pronounced circum-Atlantic mountain ranges in Norway and eastern Greenland, which have average elevation above 1500 m with peak elevations of more than 3.5 km close to Scoresby Sund in Eastern Greenland, is unknown. Our new results on the crustal structure provide data for assessment of the isostatic balance of the crust in Greenland, as well as for insight into possible links between crustal composition, rifting history and present-day topography of the North Atlantic Region.

Leads Detection Using Mixture Statistical Distribution Based CRF Algorithm from Sentinel-1 Dual Polarization SAR Imagery

NASA Astrophysics Data System (ADS)

Zhang, Yu; Li, Fei; Zhang, Shengkai; Zhu, Tingting

2017-04-01

Synthetic Aperture Radar (SAR) is significantly important for polar remote sensing since it can provide continuous observations in all days and all weather. SAR can be used for extracting the surface roughness information characterized by the variance of dielectric properties and different polarization channels, which make it possible to observe different ice types and surface structure for deformation analysis. In November, 2016, Chinese National Antarctic Research Expedition (CHINARE) 33rd cruise has set sails in sea ice zone in Antarctic. Accurate leads spatial distribution in sea ice zone for routine planning of ship navigation is essential. In this study, the semantic relationship between leads and sea ice categories has been described by the Conditional Random Fields (CRF) model, and leads characteristics have been modeled by statistical distributions in SAR imagery. In the proposed algorithm, a mixture statistical distribution based CRF is developed by considering the contexture information and the statistical characteristics of sea ice for improving leads detection in Sentinel-1A dual polarization SAR imagery. The unary potential and pairwise potential in CRF model is constructed by integrating the posteriori probability estimated from statistical distributions. For mixture statistical distribution parameter estimation, Method of Logarithmic Cumulants (MoLC) is exploited for single statistical distribution parameters estimation. The iteration based Expectation Maximal (EM) algorithm is investigated to calculate the parameters in mixture statistical distribution based CRF model. In the posteriori probability inference, graph-cut energy minimization method is adopted in the initial leads detection. The post-processing procedures including aspect ratio constrain and spatial smoothing approaches are utilized to improve the visual result. The proposed method is validated on Sentinel-1A SAR C-band Extra Wide Swath (EW) Ground Range Detected (GRD) imagery with a pixel spacing of 40 meters near Prydz Bay area, East Antarctica. Main work is listed as follows: 1) A mixture statistical distribution based CRF algorithm has been developed for leads detection from Sentinel-1A dual polarization images. 2) The assessment of the proposed mixture statistical distribution based CRF method and single distribution based CRF algorithm has been presented. 3) The preferable parameters sets including statistical distributions, the aspect ratio threshold and spatial smoothing window size have been provided. In the future, the proposed algorithm will be developed for the operational Sentinel series data sets processing due to its less time consuming cost and high accuracy in leads detection.

Data Processing, Visualization and Distribution for Support of Science Programs in the Arctic Ocean

NASA Astrophysics Data System (ADS)

Johnson, P. D.; Edwards, M. H.; Wright, D.

2006-12-01

For the past two years the Hawaii Mapping Research Group (HMRG) and Oregon State University researchers have been building an on-line archive of geophysical data for the Arctic Basin. This archive is known as AAGRUUK - the Arctic Archive for Geophysical Research: Unlocking Undersea Knowledge (http://www.soest.hawaii.edu/hmrg/Aagruuk). It contains a wide variety of data including bathymetry, sidescan and subbottom data collected by: 1) U.S. Navy nuclear-powered submarines during the Science Ice Exercises (SCICEX), 2) icebreakers such as the USCGC Healy, R/V Nathaniel B. Palmer, and CCGS Amundsen, and 3) historical depth soundings from the T3 ice camp and pre-1990 nuclear submarine missions. Instead of simply soliciting data, reformatting it, and serving it to the community, we have focused our efforts on producing and serving an integrated dataset. We pursued this path after experimenting with dataset integration and discovering a multitude of problems including navigational inconsistencies and systemic offsets produced by acquiring data in an ice-covered ocean. Our goal in addressing these problems, integrating the processed datasets and producing a data compilation was to prevent the myriad researchers interested in these datasets, many of whom have less experience processing geophysical data than HMRG personnel, from having to repeat the same data processing efforts. For investigators interested in pursuing their own data processing approaches, AAGRUUK also serves most of the raw data that was included in the data compilation, as well as processed versions of individual datasets. The archive also provides downloadable static chart sets for users who desire derived products for inclusion in reports, planning documents, etc. We are currently testing a prototype mapserver that allows maps of the cleaned datasets to be accessed interactively as well as providing access to the edited files that make up the datasets. Previously we have documented the types of the problems that were encountered in a general way. Over the past year we have integrated two terabytes of data, which allows us to comment on system performance from a much broader context. In this presentation we will show the types of error for each data acquisition system and also for operating conditions (e.g. ice cover, time of year, etc.). Our error analysis both illuminates our approach to data processing and serves as a guide for, when possible, choosing the type of instruments and the optimal time to conduct these types of surveys in ice-covered oceans.

Clouds Sailing Overhead on Mars, Unenhanced

NASA Image and Video Library

2017-08-09

Wispy clouds float across the Martian sky in this accelerated sequence of images from NASA's Curiosity Mars rover. The rover's Navigation Camera (Navcam) took these eight images over a span of four minutes early in the morning of the mission's 1,758th Martian day, or sol (July 17, 2017), aiming nearly straight overhead. This sequence uses raw images, which include a bright ring around the center of the frame that is an artifact of sunlight striking the camera lens even though the Sun is not in the shot. A processed version removing that artifact and emphasizing changes between images is also available. The clouds resemble Earth's cirrus clouds, which are ice crystals at high altitudes. These Martian clouds are likely composed of crystals of water ice that condense onto dust grains in the cold Martian atmosphere. Cirrus wisps appear as ice crystals fall and evaporate in patterns known as "fall streaks" or "mare's tails." Such patterns have been seen before at high latitudes on Mars, for instance by the Phoenix Mars Lander in 2008, and seasonally nearer the equator, for instance by the Opportunity rover. However, Curiosity has not previously observed such clouds so clearly visible from the rover's study area about five degrees south of the equator. The Hubble Space Telescope and spacecraft orbiting Mars have observed a band of clouds to appear near the Martian equator around the time of the Martian year when the planet is farthest from the Sun. With a more elliptical orbit than Earth's, Mars experiences more annual variation than Earth in its distance from the Sun. The most distant point in an orbit around the Sun is called the aphelion. The near-equatorial Martian cloud pattern observed at that time of year is called the "aphelion cloud belt." These new images from Curiosity were taken about two months before aphelion, but the morning clouds observed may be an early stage of the aphelion cloud belt. An animation is available at https://photojournal.jpl.nasa.gov/catalog/PIA21842

Supporting inland waterway transport on German waterways by operational forecasting services - water-levels, discharges, river ice

NASA Astrophysics Data System (ADS)

Meißner, Dennis; Klein, Bastian; Ionita, Monica; Hemri, Stephan; Rademacher, Silke

2017-04-01

Inland waterway transport (IWT) is an important commercial sector significantly vulnerable to hydrological impacts. River ice and floods limit the availability of the waterway network and may cause considerable damages to waterway infrastructure. Low flows significantly affect IWT's operation efficiency usually several months a year due to the close correlation of (low) water levels / water depths and (high) transport costs. Therefore "navigation-related" hydrological forecasts focussing on the specific requirements of water-bound transport (relevant forecast locations, target parameters, skill characteristics etc.) play a major role in order to mitigate IWT's vulnerability to hydro-meteorological impacts. In light of continuing transport growth within the European Union, hydrological forecasts for the waterways are essential to stimulate the use of the free capacity IWT still offers more consequently. An overview of the current operational and pre-operational forecasting systems for the German waterways predicting water levels, discharges and river ice thickness on various time-scales will be presented. While short-term (deterministic) forecasts have a long tradition in navigation-related forecasting, (probabilistic) forecasting services offering extended lead-times are not yet well-established and are still subject to current research and development activities (e.g. within the EU-projects EUPORIAS and IMPREX). The focus is on improving technical aspects as well as on exploring adequate ways of disseminating and communicating probabilistic forecast information. For the German stretch of the River Rhine, one of the most frequented inland waterways worldwide, the existing deterministic forecast scheme has been extended by ensemble forecasts combined with statistical post-processing modules applying EMOS (Ensemble Model Output Statistics) and ECC (Ensemble Copula Coupling) in order to generate water level predictions up to 10 days and to estimate its predictive uncertainty properly. Additionally for the key locations at the international waterways Rhine, Elbe and Danube three competing forecast approaches are currently tested in a pre-operational set-up in order to generate monthly to seasonal (up to 3 months) forecasts: (1) the well-known Ensemble Streamflow Prediction approach (ensemble based on historical meteorology), (2) coupling hydrological models with post-processed outputs from ECMWF's general circulation model (System 4), and (3) a purely statistical approach based on the stable relationship (teleconnection) of global or regional oceanic, climate and hydrological data with river flows. The current results, still pre-operational, reveal the existence of a valuable predictability of water levels and streamflow also at monthly up to seasonal time-scales along the larger rivers used as waterways in Germany. Last but not least insight into the technical set-up of the aforementioned forecasting systems operated at the Federal Institute of Hydrology, which are based on a Delft-FEWS application, will be given focussing on the step-wise extension of the former system by integrating new components in order to meet the growing needs of the customers and to improve and extend the forecast portfolio for waterway users.

Monitoring global climate change using SLR data from LARES and other geodetic satellites

NASA Astrophysics Data System (ADS)

Paolozzi, Antonio; Paris, Claudio; Pavlis, Erricos C.; Sindoni, Giampiero; Ciufolini, Ignazio

2016-04-01

The Earth Orientation Parameters (EOP), i.e. the spin axis of the Earth, is influenced by the mass redistribution inside and on the surface of the Earth. On the Earth surface, global ice melting, sea level change and atmospheric circulation are the prime contributors. Recent studies have unraveled the majority of the mysteries behind the Chandler wobble, the annual motion and the secular motion of the pole. The differences from the motion of a pole for a rigid Earth is indeed due to the mass redistribution and transfer of angular momentum among the atmosphere, the oceans and solid Earth. The technique of laser ranging and the use of laser ranged satellites such as LARES along with other techniques such Very Long Baseline Interferometry (VLBI) allow to measure the EOP with accuracies at the level of ~200 μas which correspond to few millimeters at the Earth's surface, while the use of Global Navigation Satellite System (GNSS) data can reach an accuracy even below 100 μas. At these unprecedented high levels of accuracy, even tiny anomalous behavior in EOP can be observed and thus correlated to global environmental changes such as ice melting on Greenland and the polar caps, and extreme events that involve strong ocean-atmosphere coupling interactions such as the El Niño. The contribution of Satellite Laser Ranging (SLR) data such as from the LARES mission and similar satellites to this area is outlined in this paper.

Multi-Sensor Mud Detection

NASA Technical Reports Server (NTRS)

Rankin, Arturo L.; Matthies, Larry H.

2010-01-01

Robust mud detection is a critical perception requirement for Unmanned Ground Vehicle (UGV) autonomous offroad navigation. A military UGV stuck in a mud body during a mission may have to be sacrificed or rescued, both of which are unattractive options. There are several characteristics of mud that may be detectable with appropriate UGV-mounted sensors. For example, mud only occurs on the ground surface, is cooler than surrounding dry soil during the daytime under nominal weather conditions, is generally darker than surrounding dry soil in visible imagery, and is highly polarized. However, none of these cues are definitive on their own. Dry soil also occurs on the ground surface, shadows, snow, ice, and water can also be cooler than surrounding dry soil, shadows are also darker than surrounding dry soil in visible imagery, and cars, water, and some vegetation are also highly polarized. Shadows, snow, ice, water, cars, and vegetation can all be disambiguated from mud by using a suite of sensors that span multiple bands in the electromagnetic spectrum. Because there are military operations when it is imperative for UGV's to operate without emitting strong, detectable electromagnetic signals, passive sensors are desirable. JPL has developed a daytime mud detection capability using multiple passive imaging sensors. Cues for mud from multiple passive imaging sensors are fused into a single mud detection image using a rule base, and the resultant mud detection is localized in a terrain map using range data generated from a stereo pair of color cameras.

Spinoff 2011

NASA Technical Reports Server (NTRS)

2012-01-01

Topics include: Bioreactors Drive Advances in Tissue Engineering; Tooling Techniques Enhance Medical Imaging; Ventilator Technologies Sustain Critically Injured Patients; Protein Innovations Advance Drug Treatments, Skin Care; Mass Analyzers Facilitate Research on Addiction; Frameworks Coordinate Scientific Data Management; Cameras Improve Navigation for Pilots, Drivers; Integrated Design Tools Reduce Risk, Cost; Advisory Systems Save Time, Fuel for Airlines; Modeling Programs Increase Aircraft Design Safety; Fly-by-Wire Systems Enable Safer, More Efficient Flight; Modified Fittings Enhance Industrial Safety; Simulation Tools Model Icing for Aircraft Design; Information Systems Coordinate Emergency Management; Imaging Systems Provide Maps for U.S. Soldiers; High-Pressure Systems Suppress Fires in Seconds; Alloy-Enhanced Fans Maintain Fresh Air in Tunnels; Control Algorithms Charge Batteries Faster; Software Programs Derive Measurements from Photographs; Retrofits Convert Gas Vehicles into Hybrids; NASA Missions Inspire Online Video Games; Monitors Track Vital Signs for Fitness and Safety; Thermal Components Boost Performance of HVAC Systems; World Wind Tools Reveal Environmental Change; Analyzers Measure Greenhouse Gasses, Airborne Pollutants; Remediation Technologies Eliminate Contaminants; Receivers Gather Data for Climate, Weather Prediction; Coating Processes Boost Performance of Solar Cells; Analyzers Provide Water Security in Space and on Earth; Catalyst Substrates Remove Contaminants, Produce Fuel; Rocket Engine Innovations Advance Clean Energy; Technologies Render Views of Earth for Virtual Navigation; Content Platforms Meet Data Storage, Retrieval Needs; Tools Ensure Reliability of Critical Software; Electronic Handbooks Simplify Process Management; Software Innovations Speed Scientific Computing; Controller Chips Preserve Microprocessor Function; Nanotube Production Devices Expand Research Capabilities; Custom Machines Advance Composite Manufacturing; Polyimide Foams Offer Superior Insulation; Beam Steering Devices Reduce Payload Weight; Models Support Energy-Saving Microwave Technologies; Materials Advance Chemical Propulsion Technology; and High-Temperature Coatings Offer Energy Savings.

NASA Scientific Balloon in Antarctica

NASA Image and Video Library

2017-12-08

NASA image captured December 25, 2011 A NASA scientific balloon awaits launch in McMurdo, Antarctica. The balloon, carrying Indiana University's Cosmic Ray Electron Synchrotron Telescope (CREST), was launched on December 25. After a circum-navigational flight around the South Pole, the payload landed on January 5. The CREST payload is one of two scheduled as part of this seasons' annual NASA Antarctic balloon Campaign which is conducted in cooperation with the National Science Foundation's Office of Polar Programs. The campaign's second payload is the University of Arizona's Stratospheric Terahertz Observatory (STO). You can follow the flights at the Columbia Scientific Balloon Facility's web site at www.csbf.nasa.gov/antarctica/ice.htm Credit: NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

An Assessment of Aerocapture and Applications to Future Missions to Uranus and Neptune

NASA Astrophysics Data System (ADS)

Beauchamp, P. M.; Spilker, T. R.

2017-12-01

Our investigation examined the current state of readiness of aerocapture at several destinations of interest, including Uranus and Neptune, to identify what technologies are needed, and to determine if a technology demonstration mission is required, prior to the first use of aerocapture for a science mission. The study team concluded that the current state of readiness is destination dependent, with aerocaptured missions feasible at Venus, Mars, and Titan with current technologies. The use of aerocapture for orbit insertion at the ice giant planets Uranus and Neptune requires at least additional study to assess the expected performance of new guidance, navigation, and control algorithms, and possible development of new hardware, such as a mid-L/D entry vehicle shape or new thermal protection system materials. A variety of near-term activities could contribute to risk reduction for missions proposing use of aerocapture, but a system-level technology demonstration mission is not deemed necessary before the use of aerocapture for a NASA science mission.

Regulatory Supervision of Radiological Protection in the Russian Federation as Applied to Facility Decommissioning and Site Remediation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sneve, M.K.; Shandala, N.K.

2007-07-01

The Russian Federation is carrying out major work to manage the legacy of exploitation of nuclear power and use of radioactive materials. This paper describes work on-going to provide enhanced regulatory supervision of these activities as regards radiological protection. The scope includes worker and public protection in routine operation; emergency preparedness and response; radioactive waste management, including treatment, interim storage and transport as well as final disposal; and long term site restoration. Examples examined include waste from facilities in NW Russia, including remediation of previous shore technical bases (STBs) for submarines, spent fuel and radioactive waste management from ice-breakers, andmore » decommissioning of Radio-Thermal-Generators (RTGs) used in navigational devices. Consideration is given to the identification of regulatory responsibilities among different regulators; development of necessary regulatory instruments; and development of regulatory procedures for safety case reviews and compliance monitoring and international cooperation between different regulators. (authors)« less

On the polarization of light in atmospheres and oceans

NASA Astrophysics Data System (ADS)

Yang, P.; Kattawar, G. W.; Mishchenko, M. I.

2016-12-01

In this talk, we will briefly review the genesis and evolution of the polarization of light, dating back to the Vikings' questionable use of sunstones for navigation. Also to be presented are the first use of polarimetry in the study of planetary atmospheres and stars as well as the latest results on the use of polarization by both terrestrial and marine organisms. In particular, our presentation will focus on the representation of the polarization characteristics of light in terms of the Stokes vector-Mueller matrix formalism. In addition, we will discuss the features of the polarization properties of nonspherical particles. Furthermore, we will illustrate the great potential of using the polarization properties of light in downstream applications, particularly remote sensing of the optical and microphysical properties of airborne dust and ice crystals. We will also show the effect of coherence of the illuminating source on the polarization properties of atmospheric particles since sunlight only has a lateral coherence length of roughly 60 μm.

The Rise of GNSS Reflectometry for Earth Remote Sensing

NASA Technical Reports Server (NTRS)

Zuffada, Cinzia; Li, Zhijin; Nghiem, Son V.; Lowe, Steve; Shah, Rashmi; Clarizia, Maria Paola; Cardellach, Estel

2015-01-01

The Global Navigation Satellite System (GNSS) reflectometry, i.e. GNSS-R, is a novel remote-sensing technique first published in that uses GNSS signals reflected from the Earth's surface to infer its surface properties such as sea surface height (SSH), ocean winds, sea-ice coverage, vegetation, wetlands and soil moisture, to name a few. This communication discusses the scientific value of GNSS-R to (a) furthering our understanding of ocean mesoscale circulation toward scales finer than those that existing nadir altimeters can resolve, and (b) mapping vegetated wetlands, an emerging application that might open up new avenues to map and monitor the planet's wetlands for methane emission assessments. Such applications are expected to be demonstrated by the availability of data from GEROS-ISS, an ESA experiment currently in phase A, and CyGNSS [3], a NASA mission currently in development. In particular, the paper details the expected error characteristics and the role of filtering played in the assimilation of these data to reduce the altimetric error (when averaging many measurements).

Newly Acquired Gulfstream C-131B Samaritan in the Hangar

NASA Image and Video Library

1976-11-21

The National Aeronautics and Space Administration (NASA) Lewis Research Center acquired this Gulfstream C-131B Samaritan from the Air Force in July 1976. The center obtained the aircraft to support its current earth resources work. The C-131B is seen here inside the Lewis hangar being refurbished and converted into a flying laboratory. The modifications were led by Lewis Chief of Flight Operations Robert Hogan. The cockpit and cabin were modified and packed with instrumentation. The new equipment included Sideways Looking Airborne Radar (SLAR), geothermal sensors, radar antennas, and an inertial navigation system. In addition, portals were installed underneath the fuselage for cameras and remote sensing equipment. NASA’s C-131B was used to support researchers tracking ice flows on the Great Lakes and in Prudhoe Bay, Alaska. It was also used for the center’s program to determine heating losses in the Cleveland area’s residential and commercial structures. The aircraft was later donated to the University of Georgia.

33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and... § 207.185 Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation...

33 CFR 207.185 - Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation. 207.185 Section 207.185 Navigation and... § 207.185 Taylors Bayou, Tex., Beaumont Navigation District Lock; use, administration, and navigation...

Lagrangian Modeling of Arctic Ocean Circulation Pathways: Impact of Advection on Spread of Pollutants

NASA Astrophysics Data System (ADS)

Kelly, S.; Popova, E.; Aksenov, Y.; Marsh, R.; Yool, A.

2018-04-01

Sea-ice-free summers are projected to become a prominent feature of the Arctic environment in the coming decades. From a shipping perspective, this means larger areas of open water in the summer, thinner and less compact ice all year round, and longer operating seasons. Therefore, the possibility for easier navigation along trans-Arctic shipping routes arises. The Northern Sea Route (NSR) is one trans-Arctic route, and it offers a potential 10 day shortcut between Western Europe and the Far East. More ships transiting the NSR means an increased risk of an accident, and associated oil spill, occurring. Previous research suggests that current infrastructure is insufficient for increased shipping. Therefore, should an oil spill occur, the window for a successful clean-up will be short. In the event of a failed recovery, the long-term fate of the unrecovered pollutants must be considered, at least until the next melt season when it could become accessible again. Here we investigate the role of oceanic advection in determining the long-term fate of Arctic pollutants using a high-resolution ocean model along with Lagrangian particle-tracking to simulate the spread of pollutants. The resulting "advective footprints" of pollutants are proposed as an informative metric for analyzing such experiments. We characterize the circulation along different parts of the NSR, defining three main regions in the Eurasian Arctic, and relate the distinctive circulation pathways of each to the long-term fate of spilled oil. We conclude that a detailed understanding of ocean circulation is critical for determining the long-term fate of Arctic pollutants.

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

33 CFR 164.11 - Navigation under way: General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Navigation under way: General. 164.11 Section 164.11 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.11 Navigation under way: General...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

33 CFR 164.78 - Navigation under way: Towing vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation under way: Towing vessels. 164.78 Section 164.78 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.78 Navigation under way...

33 CFR 401.54 - Interference with navigation aids.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

33 CFR 401.54 - Interference with navigation aids.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

33 CFR 401.54 - Interference with navigation aids.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

33 CFR 401.54 - Interference with navigation aids.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

78 FR 68861 - Certain Navigation Products, Including GPS Devices, Navigation and Display Systems, Radar Systems...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-15

... Devices, Navigation and Display Systems, Radar Systems, Navigational Aids, Mapping Systems and Related... navigation products, including GPS devices, navigation and display systems, radar systems, navigational aids..., radar systems, navigational aids, mapping systems and related software by reason of infringement of one...

33 CFR 100.45 - Establishment of aids to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation incidental to the holding of a regatta or marine parade are private aids to navigation as... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Establishment of aids to navigation. 100.45 Section 100.45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND...

33 CFR 401.54 - Interference with navigation aids.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Interference with navigation aids. 401.54 Section 401.54 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT CORPORATION... with navigation aids. (a) Aids to navigation shall not be interfered with or used as moorings. (b) No...

33 CFR 66.01-50 - Protection of private aids to navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained under...

33 CFR 66.01-50 - Protection of private aids to navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained under...

33 CFR 67.35-10 - Private aids to navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications § 67.35-10...

33 CFR 67.35-10 - Private aids to navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications § 67.35-10...

33 CFR 66.05-25 - Change and modification of State aids to navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines the...

33 CFR 66.01-50 - Protection of private aids to navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained under...

33 CFR 66.05-25 - Change and modification of State aids to navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines the...

33 CFR 67.35-10 - Private aids to navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications § 67.35-10...

33 CFR 67.35-10 - Private aids to navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications § 67.35-10...

33 CFR 66.01-50 - Protection of private aids to navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained under...

33 CFR 66.05-25 - Change and modification of State aids to navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines the...

33 CFR 66.05-25 - Change and modification of State aids to navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines the...

33 CFR 67.35-10 - Private aids to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Private aids to navigation. 67.35-10 Section 67.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES Applications § 67.35-10...

33 CFR 66.01-50 - Protection of private aids to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Protection of private aids to... SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-50 Protection of private aids to navigation. Private aids to navigation lawfully maintained under...

33 CFR 66.05-25 - Change and modification of State aids to navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... aids to navigation. 66.05-25 Section 66.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-25 Change and modification of State aids to navigation. Wherever a State Administrator determines the...

Connecting Polar Literature with Contemporary Research

NASA Astrophysics Data System (ADS)

Pfirman, S.; Bell, R.; Fowler, C.

2006-12-01

The public is fascinated with polar research, especially when it is linked with exploration, discovery, adventure, isolation, self-reliance, hardship, and exotic landscapes and biota. A powerful way to engage the public in appreciating current research is to link it with accounts of historical expeditions. We have been doing this at Barnard College, Columbia University, since 2003 through "Exploring the Poles," a First Year Seminar. The class investigates polar exploration at the turn of the last century by reading "Farthest North" by Nansen about his adventure with the Fram, "The Last Place on Earth" by Huntford about Scott and Amundsen's race to the South Pole, and "Endurance" by Lansing about Shackleton's journey. To bring polar conditions home for the students, they are assigned to expedition teams for specific years and the fates of the student "expeditions" are based on the actual environmental conditions as well as their own decisions. For example, in the Arctic, student teams navigate satellite images of coastal ice and then freeze their ships into the sea ice north of Siberia, where they then drift with the ice across the pole, re-creating the transit of the Fram. Because the conditions are based on actual data, natural variability causes different outcomes for different years, creating an element of suspense. Fates of the teams vary tremendously: some teams emerge safely as Nansen did at Fram Strait or reach Elephant Island as happened with Shackleton, while others nearly become hopelessly lost in the Arctic Beaufort Gyre or drift out to sea into the Antarctic Circumpolar Current. Interweaving history, science, and stories of past and present expeditions provides a meaningful connection with the otherwise remote polar regions. Evaluation shows that combining historical texts with current data and simulations is an extremely powerful way of engaging non-scientists in science, and explaining the role of science and the environment in decision- making. Students come to understand issues faced by leaders as they deal with environmental uncertainty, and they become interested in science as they find themselves at the mercy of the elements. The interaction between current research and historical experience as well as the physical and social environments has applications in both formal and informal educational venues.

Using GNSS-R techniques to investigate the near sub-surface of Mars with the Deep Space Network

NASA Astrophysics Data System (ADS)

Elliott, H. M.; Bell, D. J.; Jin, C.; Decrossas, E.; Asmar, S.; Lazio, J.; Preston, R. A.; Ruf, C. S.; Renno, N. O.

2017-12-01

Global Navigation Satellite Systems Reflectometry (GNSS-R) has shown that passive measurements using separate active sources can infer the soil moisture, snow pack depth and other quantities of scientific interest. Here, we expand upon this method and propose that a passive measurement of the sub-surface dielectric profile of Mars can be made by using multipath interference between reflections off the surface and subsurface dielectric discontinuities. This measurement has the ability to reveal changes in the soil water content, the depth of a layer of sand, thickness of a layer of ice, and even identify centimeter-scale layering which may indicate the presence of a sedimentary bed. We have created a numerical ray tracing model to understand the potential of using multipath interference techniques to investigate the sub-surface dielectric properties and structure of Mars. We have further verified this model using layered beds of sand and concrete in laboratory experiments and then used the model to extrapolate how this technique may be applied to future Mars missions. We will present new results demonstrating how to characterize a multipath interference patterns as a function of frequency and/or incidence angle to measure the thickness of a dielectric layer of sand or ice. Our results demonstrate that dielectric discontinuities in the subsurface can be measured using this passive sensing technique and it could be used to effectively measure the thickness of a dielectric layer in the proximity of a landed spacecraft. In the case of an orbiter, we believe this technique would be effective at measuring the seasonal thickness of CO2 ice in the Polar Regions. This is exciting because our method can produce similar results to traditional ground penetrating radars without the need to have an active radar transmitter in-situ. Therefore, it is possible that future telecommunications systems can serve as both a radio and a scientific instrument when used in conjunction with the Deep Space Network, a huge potential cost-savings for interplanetary missions.

The effect of sediment loading in Fennoscandia and the Barents Sea during the last glacial cycle on glacial isostatic adjustment observations

NASA Astrophysics Data System (ADS)

van der Wal, Wouter; IJpelaar, Thijs

2017-09-01

Models for glacial isostatic adjustment (GIA) routinely include the effects of meltwater redistribution and changes in topography and coastlines. Since the sediment transport related to the dynamics of ice sheets may be comparable to that of sea level rise in terms of surface pressure, the loading effect of sediment deposition could cause measurable ongoing viscous readjustment. Here, we study the loading effect of glacially induced sediment redistribution (GISR) related to the Weichselian ice sheet in Fennoscandia and the Barents Sea. The surface loading effect and its effect on the gravitational potential is modeled by including changes in sediment thickness in the sea level equation following the method of Dalca et al. (2013). Sediment displacement estimates are estimated in two different ways: (i) from a compilation of studies on local features (trough mouth fans, large-scale failures, and basin flux) and (ii) from output of a coupled ice-sediment model. To account for uncertainty in Earth's rheology, three viscosity profiles are used. It is found that sediment transport can lead to changes in relative sea level of up to 2 m in the last 6000 years and larger effects occurring earlier in the deglaciation. This magnitude is below the error level of most of the relative sea level data because those data are sparse and errors increase with length of time before present. The effect on present-day uplift rates reaches a few tenths of millimeters per year in large parts of Norway and Sweden, which is around the measurement error of long-term GNSS (global navigation satellite system) monitoring networks. The maximum effect on present-day gravity rates as measured by the GRACE (Gravity Recovery and Climate Experiment) satellite mission is up to tenths of microgal per year, which is larger than the measurement error but below other error sources. Since GISR causes systematic uplift in most of mainland Scandinavia, including GISR in GIA models would improve the interpretation of GNSS and GRACE observations there.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, Philip E.; Wurstner, Signe K.; Sullivan, E. C.

Ice coverage of the Arctic Ocean is predicted to become thinner and to cover less area with time. The combination of more ice-free waters for exploration and navigation, along with increasing demand for hydrocarbons and improvements in technologies for the discovery and exploitation of new hydrocarbon resources have focused attention on the hydrocarbon potential of the Arctic Basin and its margins. The purpose of this document is to 1) summarize results of a review of published hydrocarbon resources in the Arctic, including both conventional oil and gas and methane hydrates and 2) develop a set of digital maps of themore » hydrocarbon potential of the Arctic Ocean. These maps can be combined with predictions of ice-free areas to enable estimates of the likely regions and sequence of hydrocarbon production development in the Arctic. In this report, conventional oil and gas resources are explicitly linked with potential gas hydrate resources. This has not been attempted previously and is particularly powerful as the likelihood of gas production from marine gas hydrates increases. Available or planned infrastructure, such as pipelines, combined with the geospatial distribution of hydrocarbons is a very strong determinant of the temporal-spatial development of Arctic hydrocarbon resources. Significant unknowns decrease the certainty of predictions for development of hydrocarbon resources. These include: 1) Areas in the Russian Arctic that are poorly mapped, 2) Disputed ownership: primarily the Lomonosov Ridge, 3) Lack of detailed information on gas hydrate distribution, and 4) Technical risk associated with the ability to extract methane gas from gas hydrates. Logistics may control areas of exploration more than hydrocarbon potential. Accessibility, established ownership, and leasing of exploration blocks may trump quality of source rock, reservoir, and size of target. With this in mind, the main areas that are likely to be explored first are the Bering Strait and Chukchi Sea, in spite of the fact that these areas do not have highest potential for future hydrocarbon reserves. Opportunities for improving the mapping and assessment of Arctic hydrocarbon resources include: 1) Refining hydrocarbon potential on a basin-by-basin basis, 2) Developing more realistic and detailed distribution of gas hydrate, and 3) Assessing the likely future scenarios for development of infrastructure and their interaction with hydrocarbon potential. It would also be useful to develop a more sophisticated approach to merging conventional and gas hydrate resource potential that considers the technical uncertainty associated with exploitation of gas hydrate resources. Taken together, additional work in these areas could significantly improve our understanding of the exploitation of Arctic hydrocarbons as ice-free areas increase in the future.« less

33 CFR 66.05-35 - Private aids to navigation other than State owned.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality not...

33 CFR 66.05-35 - Private aids to navigation other than State owned.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality not...

33 CFR 66.05-35 - Private aids to navigation other than State owned.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality not...

33 CFR 66.05-35 - Private aids to navigation other than State owned.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality not...

33 CFR 66.05-35 - Private aids to navigation other than State owned.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Private aids to navigation other... HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-35 Private aids to navigation other than State owned. (a) No person, public body or other instrumentality not...

Cost-Effectiveness of Patient Navigation to Increase Adherence with Screening Colonoscopy Among Minority Individuals

PubMed Central

Ladabaum, Uri; Mannalithara, Ajitha; Jandorf, Lina; Itzkowitz, Steven H.

2015-01-01

Background Colorectal cancer (CRC) screening is underutilized by minority populations. Patient navigation increases adherence with screening colonoscopy. We estimated the cost-effectiveness of navigation for screening colonoscopy from the perspective of a payer seeking to improve population health. Methods We informed our validated model of CRC screening with inputs from navigation studies in New York City (population 43% African American, 49% Hispanic, 4% White, 4% Other; base case screening 40% without and 65% with navigation, navigation costs $29/colonoscopy completer, $21/non-completer, $3/non-navigated). We compared: 1) navigation vs. no navigation for one-time screening colonoscopy in unscreened persons age ≥50; 2) programs of colonoscopy with vs. without navigation, vs. fecal occult blood testing (FOBT) or immunochemical testing (FIT) for ages 50-80. Results In the base case: 1) one-time navigation gained quality-adjusted life-years (QALYs) and decreased costs; 2) longitudinal navigation cost $9,800/QALY gained vs. no navigation, and assuming comparable uptake rates, it cost $118,700/QALY gained vs. FOBT, but was less effective and more costly than FIT. Results were most dependent on screening participation rates and navigation costs: 1) assuming a 5% increase in screening uptake with navigation and navigation cost of $150/completer, one-time navigation cost $26,400/QALY gained; 2) longitudinal navigation with 75% colonoscopy uptake cost <$25,000/QALY gained vs. FIT when FIT uptake was <50%. Probabilistic sensitivity analyses did not alter the conclusions. Conclusions Navigation for screening colonoscopy appears to be cost-effective, and one-time navigation may be cost-saving. In emerging healthcare models that reward outcomes, payers should consider covering the costs of navigation for screening colonoscopy. PMID:25492455

33 CFR 149.510 - How do I get permission to establish an aid to navigation?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false How do I get permission to establish an aid to navigation? 149.510 Section 149.510 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.510 How do I get permission to establish an aid to navigation? (a...

33 CFR 149.510 - How do I get permission to establish an aid to navigation?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false How do I get permission to establish an aid to navigation? 149.510 Section 149.510 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.510 How do I get permission to establish an aid to navigation? (a...

33 CFR 207.169 - Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation. 207.169 Section 207.169 Navigation... REGULATIONS § 207.169 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and...

33 CFR 207.169 - Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and navigation. 207.169 Section 207.169 Navigation... REGULATIONS § 207.169 Oklawaha River, navigation lock and dam at Moss Bluff, Fla.; use, administration, and...

Terrain matching image pre-process and its format transform in autonomous underwater navigation

NASA Astrophysics Data System (ADS)

Cao, Xuejun; Zhang, Feizhou; Yang, Dongkai; Yang, Bogang

2007-06-01

Underwater passive navigation technology is one of the important development orientations in the field of modern navigation. With the advantage of high self-determination, stealth at sea, anti-jamming and high precision, passive navigation is completely meet with actual navigation requirements. Therefore passive navigation has become a specific navigating method for underwater vehicles. The scientists and researchers in the navigating field paid more attention to it. The underwater passive navigation can provide accurate navigation information with main Inertial Navigation System (INS) for a long period, such as location and speed. Along with the development of micro-electronics technology, the navigation of AUV is given priority to INS assisted with other navigation methods, such as terrain matching navigation. It can provide navigation ability for a long period, correct the errors of INS and make AUV not emerge from the seabed termly. With terrain matching navigation technique, in the assistance of digital charts and ocean geographical characteristics sensors, we carry through underwater image matching assistant navigation to obtain the higher location precision, therefore it is content with the requirement of underwater, long-term, high precision and all-weather of the navigation system for Autonomous Underwater Vehicles. Tertian-assistant navigation (TAN) is directly dependent on the image information (map information) in the navigating field to assist the primary navigation system according to the path appointed in advance. In TAN, a factor coordinative important with the system operation is precision and practicability of the storable images and the database which produce the image data. If the data used for characteristics are not suitable, the system navigation precision will be low. Comparing with terrain matching assistant navigation system, image matching navigation system is a kind of high precision and low cost assistant navigation system, and its matching precision directly influences the final precision of integrated navigation system. Image matching assistant navigation is spatially matching and aiming at two underwater scenery images coming from two different sensors matriculating of the same scenery in order to confirm the relative displacement of the two images. In this way, we can obtain the vehicle's location in fiducial image known geographical relation, and the precise location information given from image matching location is transmitted to INS to eliminate its location error and greatly enhance the navigation precision of vehicle. Digital image data analysis and processing of image matching in underwater passive navigation is important. In regard to underwater geographic data analysis, we focus on the acquirement, disposal, analysis, expression and measurement of database information. These analysis items structure one of the important contents of underwater terrain matching and are propitious to know the seabed terrain configuration of navigation areas so that the best advantageous seabed terrain district and dependable navigation algorithm can be selected. In this way, we can improve the precision and reliability of terrain assistant navigation system. The pre-process and format transformation of digital image during underwater image matching are expatiated in this paper. The information of the terrain status in navigation areas need further study to provide the reliable data terrain characteristic and underwater overcast for navigation. Through realizing the choice of sea route, danger district prediction and navigating algorithm analysis, TAN can obtain more high location precision and probability, hence provide technological support for image matching of underwater passive navigation.

33 CFR 62.63 - Recommendations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Recommendations. 62.63 Section 62.63 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM Public Participation in the Aids to Navigation System § 62.63...

33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to...

33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to...

33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to...

33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to...

33 CFR 66.01-12 - May I continue to use the private aid to navigation I am currently using?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false May I continue to use the private aid to navigation I am currently using? 66.01-12 Section 66.01-12 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 165.714 - Regulated Navigation Area; Atlantic Ocean, Charleston, SC.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area; Atlantic Ocean, Charleston, SC. 165.714 Section 165.714 Navigation and Navigable Waters COAST GUARD... § 165.714 Regulated Navigation Area; Atlantic Ocean, Charleston, SC. (a) Location. The following area is...

33 CFR 66.01-40 - Exemptions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Exemptions. 66.01-40 Section 66.01-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-40 Exemptions. (a...

33 CFR 66.01-40 - Exemptions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Exemptions. 66.01-40 Section 66.01-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-40 Exemptions. (a...

33 CFR 62.31 - Special marks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Special marks. 62.31 Section 62.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.31 Special marks. Special...

33 CFR 70.05-1 - General provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false General provisions. 70.05-1 Section 70.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 66.01-5 - Application procedure.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Application procedure. 66.01-5 Section 66.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-5 Application...

33 CFR 66.05-5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

....05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-5 Definitions. (a) The term State waters for private aids to navigation means those navigable waters of the United States which the Commandant, upon...

33 CFR 66.01-45 - Penalties.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Penalties. 66.01-45 Section 66.01-45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-45 Penalties. Any person...

33 CFR 62.25 - Lateral marks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Lateral marks. 62.25 Section 62.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.25 Lateral marks. (a...

33 CFR 62.32 - Inland waters obstruction mark.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Inland waters obstruction mark. 62.32 Section 62.32 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.32...

33 CFR 62.33 - Information and regulatory marks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Information and regulatory marks. 62.33 Section 62.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.33...

33 CFR 62.41 - Ranges.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Ranges. 62.41 Section 62.41 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.41 Ranges. Ranges are aids to...

33 CFR 66.05-5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

....05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-5 Definitions. (a) The term State waters for private aids to navigation means those navigable waters of the United States which the Commandant, upon...

33 CFR 62.29 - Isolated danger marks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Isolated danger marks. 62.29 Section 62.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.29 Isolated danger...

33 CFR 62.32 - Inland waters obstruction mark.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Inland waters obstruction mark. 62.32 Section 62.32 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.32...

33 CFR 62.31 - Special marks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Special marks. 62.31 Section 62.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.31 Special marks. Special...

33 CFR 66.01-45 - Penalties.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Penalties. 66.01-45 Section 66.01-45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-45 Penalties. Any person...

33 CFR 66.01-40 - Exemptions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Exemptions. 66.01-40 Section 66.01-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-40 Exemptions. (a...

33 CFR 62.29 - Isolated danger marks.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Isolated danger marks. 62.29 Section 62.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.29 Isolated danger...

33 CFR 70.05-20 - Report required.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Report required. 70.05-20 Section 70.05-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 66.01-45 - Penalties.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Penalties. 66.01-45 Section 66.01-45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-45 Penalties. Any person...

33 CFR 70.01-1 - General provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false General provisions. 70.01-1 Section 70.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-1...

33 CFR 62.33 - Information and regulatory marks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Information and regulatory marks. 62.33 Section 62.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.33...

33 CFR 66.01-5 - Application procedure.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Application procedure. 66.01-5 Section 66.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-5 Application...

33 CFR 62.31 - Special marks.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Special marks. 62.31 Section 62.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.31 Special marks. Special...

33 CFR 62.41 - Ranges.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Ranges. 62.41 Section 62.41 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.41 Ranges. Ranges are aids to...

33 CFR 66.01-40 - Exemptions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Exemptions. 66.01-40 Section 66.01-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-40 Exemptions. (a...

33 CFR 62.25 - Lateral marks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Lateral marks. 62.25 Section 62.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.25 Lateral marks. (a...

33 CFR 62.33 - Information and regulatory marks.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Information and regulatory marks. 62.33 Section 62.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.33...

33 CFR 70.01-1 - General provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false General provisions. 70.01-1 Section 70.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-1...

33 CFR 70.05-20 - Report required.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Report required. 70.05-20 Section 70.05-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 62.25 - Lateral marks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Lateral marks. 62.25 Section 62.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.25 Lateral marks. (a...

33 CFR 62.29 - Isolated danger marks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Isolated danger marks. 62.29 Section 62.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.29 Isolated danger...

33 CFR 70.05-1 - General provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false General provisions. 70.05-1 Section 70.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.05-20 - Report required.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Report required. 70.05-20 Section 70.05-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 62.31 - Special marks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Special marks. 62.31 Section 62.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.31 Special marks. Special...

33 CFR 62.32 - Inland waters obstruction mark.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Inland waters obstruction mark. 62.32 Section 62.32 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.32...

33 CFR 62.37 - Lighthouses.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Lighthouses. 62.37 Section 62.37 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.37 Lighthouses. Lighthouses are...

33 CFR 62.37 - Lighthouses.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Lighthouses. 62.37 Section 62.37 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.37 Lighthouses. Lighthouses are...

33 CFR 62.37 - Lighthouses.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Lighthouses. 62.37 Section 62.37 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.37 Lighthouses. Lighthouses are...

33 CFR 66.05-5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

....05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-5 Definitions. (a) The term State waters for private aids to navigation means those navigable waters of the United States which the Commandant, upon...

33 CFR 70.01-1 - General provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false General provisions. 70.01-1 Section 70.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-1...

33 CFR 70.01-1 - General provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false General provisions. 70.01-1 Section 70.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-1...

33 CFR 70.05-1 - General provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false General provisions. 70.05-1 Section 70.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 62.33 - Information and regulatory marks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Information and regulatory marks. 62.33 Section 62.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.33...

33 CFR 70.05-20 - Report required.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Report required. 70.05-20 Section 70.05-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.05-1 - General provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false General provisions. 70.05-1 Section 70.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 62.32 - Inland waters obstruction mark.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Inland waters obstruction mark. 62.32 Section 62.32 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.32...

33 CFR 66.01-45 - Penalties.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Penalties. 66.01-45 Section 66.01-45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-45 Penalties. Any person...

33 CFR 62.29 - Isolated danger marks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Isolated danger marks. 62.29 Section 62.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.29 Isolated danger...

33 CFR 62.41 - Ranges.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Ranges. 62.41 Section 62.41 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.41 Ranges. Ranges are aids to...

33 CFR 62.25 - Lateral marks.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Lateral marks. 62.25 Section 62.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.25 Lateral marks. (a...

33 CFR 62.37 - Lighthouses.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Lighthouses. 62.37 Section 62.37 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.37 Lighthouses. Lighthouses are...

33 CFR 66.05-5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

....05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-5 Definitions. (a) The term State waters for private aids to navigation means those navigable waters of the United States which the Commandant, upon...

33 CFR 66.01-5 - Application procedure.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Application procedure. 66.01-5 Section 66.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-5 Application...

33 CFR 62.41 - Ranges.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Ranges. 62.41 Section 62.41 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.41 Ranges. Ranges are aids to...

33 CFR 72.05-1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Purpose. 72.05-1 Section 72.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARINE... navigation maintained by or under authority of the U.S. Coast Guard, which are placed in navigable waters...

33 CFR 70.05-1 - General provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false General provisions. 70.05-1 Section 70.05-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 66.01-45 - Penalties.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Penalties. 66.01-45 Section 66.01-45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-45 Penalties. Any person...

33 CFR 70.01-1 - General provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false General provisions. 70.01-1 Section 70.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-1...

33 CFR 62.37 - Lighthouses.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lighthouses. 62.37 Section 62.37 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.37 Lighthouses. Lighthouses are...

33 CFR 66.05-5 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

....05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-5 Definitions. (a) The term State waters for private aids to navigation means those navigable waters of the United States which the Commandant, upon...

33 CFR 62.31 - Special marks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Special marks. 62.31 Section 62.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.31 Special marks. Special...

33 CFR 62.41 - Ranges.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Ranges. 62.41 Section 62.41 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.41 Ranges. Ranges are aids to...

33 CFR 66.01-40 - Exemptions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Exemptions. 66.01-40 Section 66.01-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-40 Exemptions. (a...

33 CFR 70.05-20 - Report required.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Report required. 70.05-20 Section 70.05-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 62.29 - Isolated danger marks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Isolated danger marks. 62.29 Section 62.29 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.29 Isolated danger...

33 CFR 62.33 - Information and regulatory marks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Information and regulatory marks. 62.33 Section 62.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.33...

33 CFR 62.32 - Inland waters obstruction mark.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inland waters obstruction mark. 62.32 Section 62.32 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.32...

33 CFR 62.25 - Lateral marks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lateral marks. 62.25 Section 62.25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.25 Lateral marks. (a...

Interaction Effects of Hypervideo Navigation Variables in College Students' Self-Regulated Learning

ERIC Educational Resources Information Center

Azmy, Nabil

2013-01-01

The purpose of this study is to investigate the question of whether the interaction effects of hypervideo navigation variables (navigation control and navigation links) would affect college students' self-regulated learning just after their learning from instructional hypervideo programs. Navigation control (free navigation or free navigation with…

33 CFR 162.225 - Columbia and Willamette Rivers, Washington and Oregon; administration and navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Columbia and Willamette Rivers, Washington and Oregon; administration and navigation. 162.225 Section 162.225 Navigation and Navigable Waters... NAVIGATION REGULATIONS § 162.225 Columbia and Willamette Rivers, Washington and Oregon; administration and...

33 CFR 162.225 - Columbia and Willamette Rivers, Washington and Oregon; administration and navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Columbia and Willamette Rivers, Washington and Oregon; administration and navigation. 162.225 Section 162.225 Navigation and Navigable Waters... NAVIGATION REGULATIONS § 162.225 Columbia and Willamette Rivers, Washington and Oregon; administration and...

33 CFR 162.225 - Columbia and Willamette Rivers, Washington and Oregon; administration and navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Columbia and Willamette Rivers, Washington and Oregon; administration and navigation. 162.225 Section 162.225 Navigation and Navigable Waters... NAVIGATION REGULATIONS § 162.225 Columbia and Willamette Rivers, Washington and Oregon; administration and...

33 CFR 162.225 - Columbia and Willamette Rivers, Washington and Oregon; administration and navigation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Columbia and Willamette Rivers, Washington and Oregon; administration and navigation. 162.225 Section 162.225 Navigation and Navigable Waters... NAVIGATION REGULATIONS § 162.225 Columbia and Willamette Rivers, Washington and Oregon; administration and...

33 CFR 164.72 - Navigational-safety equipment, charts or maps, and publications required on towing vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigational-safety equipment, charts or maps, and publications required on towing vessels. 164.72 Section 164.72 Navigation and... NAVIGATION SAFETY REGULATIONS § 164.72 Navigational-safety equipment, charts or maps, and publications...

33 CFR 66.01-14 - Label affixed by manufacturer.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Label affixed by manufacturer. 66.01-14 Section 66.01-14 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-14...

33 CFR 66.01-14 - Label affixed by manufacturer.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Label affixed by manufacturer. 66.01-14 Section 66.01-14 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-14...

33 CFR 70.05-15 - Liability for damages.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Liability for damages. 70.05-15 Section 70.05-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.01-5 - Penalty.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Penalty. 70.01-5 Section 70.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-5 Penalty. Any person...

33 CFR 70.01-5 - Penalty.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Penalty. 70.01-5 Section 70.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-5 Penalty. Any person...

33 CFR 66.01-55 - Transfer of ownership.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Transfer of ownership. 66.01-55 Section 66.01-55 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-55 Transfer of...

33 CFR 66.01-55 - Transfer of ownership.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Transfer of ownership. 66.01-55 Section 66.01-55 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-55 Transfer of...

33 CFR 66.01-55 - Transfer of ownership.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Transfer of ownership. 66.01-55 Section 66.01-55 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-55 Transfer of...

33 CFR 70.01-5 - Penalty.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Penalty. 70.01-5 Section 70.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-5 Penalty. Any person...

33 CFR 70.05-15 - Liability for damages.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Liability for damages. 70.05-15 Section 70.05-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.05-5 - Penalty.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Penalty. 70.05-5 Section 70.05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation § 70.05-5 Penalty...

33 CFR 70.05-5 - Penalty.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Penalty. 70.05-5 Section 70.05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation § 70.05-5 Penalty...

33 CFR 70.01-5 - Penalty.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Penalty. 70.01-5 Section 70.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-5 Penalty. Any person...

33 CFR 66.01-14 - Label affixed by manufacturer.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Label affixed by manufacturer. 66.01-14 Section 66.01-14 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-14...

33 CFR 66.01-14 - Label affixed by manufacturer.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Label affixed by manufacturer. 66.01-14 Section 66.01-14 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-14...

33 CFR 70.05-15 - Liability for damages.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Liability for damages. 70.05-15 Section 70.05-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.05-15 - Liability for damages.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Liability for damages. 70.05-15 Section 70.05-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 70.05-5 - Penalty.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Penalty. 70.05-5 Section 70.05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation § 70.05-5 Penalty...

33 CFR 70.05-5 - Penalty.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Penalty. 70.05-5 Section 70.05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation § 70.05-5 Penalty...

33 CFR 66.01-55 - Transfer of ownership.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Transfer of ownership. 66.01-55 Section 66.01-55 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-55 Transfer of...

33 CFR 162.30 - Channel of Tuckerton Creek, N.J.; navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Channel of Tuckerton Creek, N.J.; navigation. 162.30 Section 162.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Tuckerton Creek, N.J.; navigation. (a) Power boats or other vessels propelled by machinery shall not proceed...

33 CFR 117.458 - Inner Harbor Navigation Canal, New Orleans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inner Harbor Navigation Canal, New Orleans. 117.458 Section 117.458 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Harbor Navigation Canal, New Orleans. (a) The draws of the SR 46 (St. Claude Avenue) bridge, mile 0.5...

33 CFR 70.01-5 - Penalty.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Penalty. 70.01-5 Section 70.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Interference With Aids to Navigation § 70.01-5 Penalty. Any person...

33 CFR 70.05-5 - Penalty.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Penalty. 70.05-5 Section 70.05-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation § 70.05-5 Penalty...

33 CFR 66.01-55 - Transfer of ownership.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Transfer of ownership. 66.01-55 Section 66.01-55 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-55 Transfer of...

33 CFR 62.27 - Safe water marks.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe...

33 CFR 66.01-14 - Label affixed by manufacturer.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Label affixed by manufacturer. 66.01-14 Section 66.01-14 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-14...

33 CFR 70.05-15 - Liability for damages.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Liability for damages. 70.05-15 Section 70.05-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION INTERFERENCE WITH OR DAMAGE TO AIDS TO NAVIGATION Collision With or Damage to Aids to Navigation...

33 CFR 207.600 - Rochester (Charlotte) Harbor, N.Y.; use, administration, and navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Rochester (Charlotte) Harbor, N.Y.; use, administration, and navigation. 207.600 Section 207.600 Navigation and Navigable Waters CORPS OF... (Charlotte) Harbor, N.Y.; use, administration, and navigation. (a)-(b) [Reserved] (c) No vessel shall moor or...

33 CFR 207.580 - Buffalo Harbor, N.Y.; use, administration, and navigation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Buffalo Harbor, N.Y.; use, administration, and navigation. 207.580 Section 207.580 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.580 Buffalo Harbor, N.Y.; use...

Minisparker profiles from Jeffreys Ledge and adjacent areas in the western Gulf of Maine

USGS Publications Warehouse

Eskenasy, Diane M.; Bailey, Norman G.

1980-01-01

A total of 250 kilometers of single-channel seismic-reflection data (28 minisparker profiles) were collected in the coastal waters of Massachusetts, north of and immediately south of Cape Ann, and on the western flank of Jeffreys Ledge, western Gulf of Maine, during the September 1978 cruise of the R/V ASTERIAS. The survey was conducted by the U.S. Geological Survey as part of the Massachusetts Cooperative Marine Geologic Program.The seismic systems used included a 1Del Norte minisparker and streamer, an Energy International Streamer, and EPC 3200 and 4100 recorders. Navigational control was established by Radar and Loran-C. The Loran-C navigation data were recorded on a Northstar 6000 system.The purpose of the cruise was to discover the significance and extent of the folded and faulted internal reflections that were first noticed on the esternmost tip of Jeffreys Ledge in line 14 of esternmost tip of Jeffreys Ledge in line 14 of rninisparker data from the 1976 R/V FAY 023 cruise.Sixteen northwest-trending lines were run off Cape Ann to investigate the deformed reflectors, now thought to represent a moraine formed by readvance of continental ice over the last glacial marine Presurnpscot Formation. Lines north and south of Cape Ann were run to locate the offshore extension of the Clinton-Newbury and Bloody Bluff fault systems.The original records can be studied at the U.S. Geological Survey offices at Woods Hole, Mass. Microfilm copies of the records can be purchased only from the National Geophysical and Solar-Terrestrial Data Center, NOAA/EDIS/NGSDC, Code D621, 325 Broadway; Boulder, CO 80303 (303-497-6338)

Atrial fibrillation ablation using remote magnetic navigation and the risk of atrial-esophageal fistula: international multicenter experience.

PubMed

Danon, Asaf; Shurrab, Mohammed; Nair, Krishnakumar Mohanan; Latcu, Decebal Gabriel; Arruda, Mauricio S; Chen, Xu; Szili-Torok, Tamas; Rossvol, Ole; Wissner, Eric E; Lashevsky, Ilan; Crystal, Eugene

2015-08-01

Remote magnetic navigation (RMN) has been used in various electrophysiological procedures, including atrial fibrillation (AF) ablation. Atrial-esophageal fistula (AEF) is one of most disastrous complications of AF ablation. We aimed to evaluate the incidence of AEF during AF ablation using RMN in comparison to manual ablation. We conducted the first international survey among RMN operators for assessment of the prevalence of AEF and procedural parameters affecting the risk. Data from parallel survey of AEF among Canadian interventional electrophysiologists (CIE) using only manual catheters served as control. Fifteen RMN operators (who performed 3637 procedures) and 25 manual CIE operators (7016 procedures) responded to the survey. RMN operators were more experienced than CIE operators (16.3 ± 8.3 vs. 9.2 ± 5.4 practice years in electrophysiology, p = 0.007). The maximal energy output in the posterior wall was higher in the operator using RMN (33 ± 5 vs. 28.6 ± 4.9 W; p = 0.02). Other parameters including use of preprocedural images, irrigated catheter, pump flow rate, esophageal temperature monitoring, intracardiac echocardiography (ICE), and general anesthesia were similar. CIE operators administered proton-pump inhibitors postoperatively significantly more than RMN operators (76 vs. 35%, p = 0.01). AEF was reported in 5 of the 7016 patients in the control group (0.07%) but in none of the RMN group (p = 0.11). AEF is a rare complication and its evaluation necessitates large-scale studies. Although no AEF case with RMN was reported in this large study or previously on the literature, the rarity of this complication prevents firm conclusion about the risk.

Destination pluto: New horizons performance during the approach phase

NASA Astrophysics Data System (ADS)

Flanigan, Sarah H.; Rogers, Gabe D.; Guo, Yanping; Kirk, Madeline N.; Weaver, Harold A.; Owen, William M.; Jackman, Coralie D.; Bauman, Jeremy; Pelletier, Frederic; Nelson, Derek; Stanbridge, Dale; Dumont, Phillip J.; Williams, Bobby; Stern, S. Alan; Olkin, Cathy B.; Young, Leslie A.; Ennico, Kimberly

2016-11-01

The New Horizons spacecraft began its journey to the Pluto-Charon system on January 19, 2006 on-board an Atlas V rocket from Cape Canaveral, Florida. As the first mission in NASA's New Frontiers program, the objective of the New Horizons mission is to perform the first exploration of ice dwarfs in the Kuiper Belt, extending knowledge of the solar system to include the icy "third zone" for the first time. Arriving at the correct time and correct position relative to Pluto on July 14, 2015 depended on the successful execution of a carefully choreographed sequence of events. The Core command sequence, which was developed and optimized over multiple years and included the highest-priority science observations during the closest approach period, was contingent on precise navigation to the Pluto-Charon system and nominal performance of the guidance and control (G&C) subsystem. The flyby and gravity assist of Jupiter on February 28, 2007 was critical in placing New Horizons on the path to Pluto. Once past Jupiter, trajectory correction maneuvers (TCMs) became the sole source of trajectory control since the spacecraft did not encounter any other planetary bodies along its flight path prior to Pluto. During the Pluto approach phase, which formally began on January 15, 2015, optical navigation images were captured primarily with the Long Range Reconnaissance Imager to refine spacecraft and Pluto-Charon system trajectory knowledge, which in turn was used to design TCMs. Orbit determination solutions were also used to update the spacecraft's on-board trajectory knowledge throughout the approach phase. Nominal performance of the G&C subsystem, accurate TCM designs, and high-quality orbit determination solutions resulted in final Pluto-relative B-plane arrival conditions that facilitated a successful first reconnaissance of the Pluto-Charon system.

33 CFR 66.01-13 - When must my newly manufactured equipment comply with these rules?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false When must my newly manufactured equipment comply with these rules? 66.01-13 Section 66.01-13 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than...

33 CFR 149.505 - What are the general requirements for aids to navigation?

Code of Federal Regulations, 2012 CFR

2012-07-01

... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter, on...

33 CFR 66.01-13 - When must my newly manufactured equipment comply with these rules?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false When must my newly manufactured equipment comply with these rules? 66.01-13 Section 66.01-13 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than...

33 CFR 149.505 - What are the general requirements for aids to navigation?

Code of Federal Regulations, 2013 CFR

2013-07-01

... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter, on...

33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions, and...

33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions, and...

33 CFR 149.505 - What are the general requirements for aids to navigation?

Code of Federal Regulations, 2011 CFR

2011-07-01

... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter, on...

33 CFR 66.01-13 - When must my newly manufactured equipment comply with these rules?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false When must my newly manufactured equipment comply with these rules? 66.01-13 Section 66.01-13 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than...

33 CFR 74.20-1 - Buoy and vessel use costs.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...

33 CFR 74.20-1 - Buoy and vessel use costs.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...

33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false State waters for private aids to... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-10 State waters for private aids to navigation; designations; revisions, and...

33 CFR 66.01-13 - When must my newly manufactured equipment comply with these rules?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false When must my newly manufactured equipment comply with these rules? 66.01-13 Section 66.01-13 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than...

33 CFR 149.505 - What are the general requirements for aids to navigation?

Code of Federal Regulations, 2014 CFR

2014-07-01

... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter, on...

33 CFR 74.20-1 - Buoy and vessel use costs.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...

33 CFR 149.505 - What are the general requirements for aids to navigation?

Code of Federal Regulations, 2010 CFR

2010-07-01

... for aids to navigation? 149.505 Section 149.505 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Aids to Navigation General § 149.505 What are the general requirements for aids to navigation? The following requirements apply to navigation aids under this subpart: (a) Section 66.01-5 of this chapter, on...

33 CFR 66.01-13 - When must my newly manufactured equipment comply with these rules?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false When must my newly manufactured equipment comply with these rules? 66.01-13 Section 66.01-13 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than...

33 CFR 162.260 - Channel leading to San Juan Harbor, P.R.; use, administration, and navigation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Channel leading to San Juan Harbor, P.R.; use, administration, and navigation. 162.260 Section 162.260 Navigation and Navigable... WATERWAYS NAVIGATION REGULATIONS § 162.260 Channel leading to San Juan Harbor, P.R.; use, administration...

33 CFR 162.260 - Channel leading to San Juan Harbor, P.R.; use, administration, and navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Channel leading to San Juan Harbor, P.R.; use, administration, and navigation. 162.260 Section 162.260 Navigation and Navigable... WATERWAYS NAVIGATION REGULATIONS § 162.260 Channel leading to San Juan Harbor, P.R.; use, administration...

33 CFR 62.27 - Safe water marks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid...

33 CFR 66.10-35 - Navigation lights.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Navigation lights. 66.10-35... NAVIGATION PRIVATE AIDS TO NAVIGATION Uniform State Waterway Marking System § 66.10-35 Navigation lights. A red light shall only be used on a solid colored red buoy. A green light shall only be used on a solid...

Refining the Patient Navigation Role in a Colorectal Cancer Screening Program: Results From an Intervention Study.

PubMed

Rohan, Elizabeth A; Slotman, Beth; DeGroff, Amy; Morrissey, Kerry Grace; Murillo, Jennifer; Schroy, Paul

2016-11-01

Oncology patient navigators help individuals overcome barriers to increase access to cancer screening, diagnosis, and timely treatment. This study, part of a randomized intervention trial investigating the efficacy of patient navigation in increasing colonoscopy completion, examined navigators' activities to ameliorate barriers to colonoscopy screening in a medically disadvantaged population. This study was conducted from 2012 through 2014 at Boston Medical Center. We analyzed navigator service delivery and survey data collected on 420 participants who were navigated for colonoscopy screening after randomization to this intervention. Key variables under investigation included barriers to colonoscopy, activities navigators undertook to reduce barriers, time navigators spent on each activity and per contact, and patient satisfaction with navigation services. Descriptive analysis assessed how navigators spent their time and examined what aspects of patient navigation were most valued by patients. Navigators spent the most time assessing patient barriers/needs; facilitating appointment scheduling; reminding patients of appointments; educating patients about colorectal cancer, the importance of screening, and the colonoscopy preparation and procedures; and arranging transportation. Navigators spent an average of 44 minutes per patient. Patients valued the navigators, especially for providing emotional/peer support and explaining screening procedures and bowel preparation clearly. Our findings help clarify the role of the navigator in colonoscopy screening within a medically disadvantaged community. These findings may help further refine the navigator role in cancer screening and treatment programs as facilities strive to effectively and efficiently integrate navigation into their services. Copyright © 2016 by the National Comprehensive Cancer Network.

Refining the Patient Navigation Role in a Colorectal Cancer Screening Program: Results From an Intervention Study

PubMed Central

Rohan, Elizabeth A.; Slotman, Beth; DeGroff, Amy; Morrissey, Kerry Grace; Murillo, Jennifer; Schroy, Paul

2017-01-01

Background Oncology patient navigators help individuals overcome barriers to increase access to cancer screening, diagnosis, and timely treatment. This study, part of a randomized intervention trial investigating the efficacy of patient navigation in increasing colonoscopy completion, examined navigators' activities to ameliorate barriers to colonoscopy screening in a medically disadvantaged population. Methods This study was conducted from 2012 through 2014 at Boston Medical Center. We analyzed navigator service delivery and survey data collected on 420 participants who were navigated for colonoscopy screening after randomization to this intervention. Key variables under investigation included barriers to colonoscopy, activities navigators undertook to reduce barriers, time navigators spent on each activity and per contact, and patient satisfaction with navigation services. Descriptive analysis assessed how navigators spent their time and examined what aspects of patient navigation were most valued by patients. Results Navigators spent the most time assessing patient barriers/needs; facilitating appointment scheduling; reminding patients of appointments; educating patients about colorectal cancer, the importance of screening, and the colonoscopy preparation and procedures; and arranging transportation. Navigators spent an average of 44 minutes per patient. Patients valued the navigators, especially for providing emotional/peer support and explaining screening procedures and bowel preparation clearly. Conclusions Our findings help clarify the role of the navigator in colonoscopy screening within a medically disadvantaged community. These findings may help further refine the navigator role in cancer screening and treatment programs as facilities strive to effectively and efficiently integrate navigation into their services. PMID:27799508

Modified Navigation Instructions for Spatial Navigation Assistance Systems Lead to Incidental Spatial Learning

PubMed Central

Gramann, Klaus; Hoepner, Paul; Karrer-Gauss, Katja

2017-01-01

Spatial cognitive skills deteriorate with the increasing use of automated GPS navigation and a general decrease in the ability to orient in space might have further impact on independence, autonomy, and quality of life. In the present study we investigate whether modified navigation instructions support incidental spatial knowledge acquisition. A virtual driving environment was used to examine the impact of modified navigation instructions on spatial learning while using a GPS navigation assistance system. Participants navigated through a simulated urban and suburban environment, using navigation support to reach their destination. Driving performance as well as spatial learning was thereby assessed. Three navigation instruction conditions were tested: (i) a control group that was provided with classical navigation instructions at decision points, and two other groups that received navigation instructions at decision points including either (ii) additional irrelevant information about landmarks or (iii) additional personally relevant information (i.e., individual preferences regarding food, hobbies, etc.), associated with landmarks. Driving performance revealed no differences between navigation instructions. Significant improvements were observed in both modified navigation instruction conditions on three different measures of spatial learning and memory: subsequent navigation of the initial route without navigation assistance, landmark recognition, and sketch map drawing. Future navigation assistance systems could incorporate modified instructions to promote incidental spatial learning and to foster more general spatial cognitive abilities. Such systems might extend mobility across the lifespan. PMID:28243219

Anisotropy of Human Horizontal and Vertical Navigation in Real Space: Behavioral and PET Correlates.

PubMed

Zwergal, Andreas; Schöberl, Florian; Xiong, Guoming; Pradhan, Cauchy; Covic, Aleksandar; Werner, Philipp; Trapp, Christoph; Bartenstein, Peter; la Fougère, Christian; Jahn, Klaus; Dieterich, Marianne; Brandt, Thomas

2016-10-17

Spatial orientation was tested during a horizontal and vertical real navigation task in humans. Video tracking of eye movements was used to analyse the behavioral strategy and combined with simultaneous measurements of brain activation and metabolism ([18F]-FDG-PET). Spatial navigation performance was significantly better during horizontal navigation. Horizontal navigation was predominantly visually and landmark-guided. PET measurements indicated that glucose metabolism increased in the right hippocampus, bilateral retrosplenial cortex, and pontine tegmentum during horizontal navigation. In contrast, vertical navigation was less reliant on visual and landmark information. In PET, vertical navigation activated the bilateral hippocampus and insula. Direct comparison revealed a relative activation in the pontine tegmentum and visual cortical areas during horizontal navigation and in the flocculus, insula, and anterior cingulate cortex during vertical navigation. In conclusion, these data indicate a functional anisotropy of human 3D-navigation in favor of the horizontal plane. There are common brain areas for both forms of navigation (hippocampus) as well as unique areas such as the retrosplenial cortex, visual cortex (horizontal navigation), flocculus, and vestibular multisensory cortex (vertical navigation). Visually guided landmark recognition seems to be more important for horizontal navigation, while distance estimation based on vestibular input might be more relevant for vertical navigation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

33 CFR 62.35 - Mooring buoys.

Code of Federal Regulations, 2013 CFR

2013-07-01

....35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.35 Mooring buoys. Mooring... identification and to avoid confusion with aids to navigation. ...

33 CFR 62.35 - Mooring buoys.

Code of Federal Regulations, 2014 CFR

2014-07-01

....35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.35 Mooring buoys. Mooring... identification and to avoid confusion with aids to navigation. ...

33 CFR 62.35 - Mooring buoys.

Code of Federal Regulations, 2011 CFR

2011-07-01

....35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.35 Mooring buoys. Mooring... identification and to avoid confusion with aids to navigation. ...

33 CFR 62.35 - Mooring buoys.

Code of Federal Regulations, 2012 CFR

2012-07-01

....35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.35 Mooring buoys. Mooring... identification and to avoid confusion with aids to navigation. ...

33 CFR 62.35 - Mooring buoys.

Code of Federal Regulations, 2010 CFR

2010-07-01

....35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.35 Mooring buoys. Mooring... identification and to avoid confusion with aids to navigation. ...

33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... waterway for marine navigation, in general terms; an appropriate chart or sketch of the area; and a general... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false State waters for private aids to navigation; designations; revisions, and revocations. 66.05-10 Section 66.05-10 Navigation and Navigable...

33 CFR 66.05-10 - State waters for private aids to navigation; designations; revisions, and revocations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... waterway for marine navigation, in general terms; an appropriate chart or sketch of the area; and a general... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false State waters for private aids to navigation; designations; revisions, and revocations. 66.05-10 Section 66.05-10 Navigation and Navigable...

33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What are the requirements for supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD... § 150.710 What are the requirements for supplying power to aids to navigation? The power of all...

33 CFR 150.710 - What are the requirements for supplying power to aids to navigation?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false What are the requirements for supplying power to aids to navigation? 150.710 Section 150.710 Navigation and Navigable Waters COAST GUARD... § 150.710 What are the requirements for supplying power to aids to navigation? The power of all...

An Effective Terrain Aided Navigation for Low-Cost Autonomous Underwater Vehicles.

PubMed

Zhou, Ling; Cheng, Xianghong; Zhu, Yixian; Dai, Chenxi; Fu, Jinbo

2017-03-25

Terrain-aided navigation is a potentially powerful solution for obtaining submerged position fixes for autonomous underwater vehicles. The application of terrain-aided navigation with high-accuracy inertial navigation systems has demonstrated meter-level navigation accuracy in sea trials. However, available sensors may be limited depending on the type of the mission. Such limitations, especially for low-grade navigation sensors, not only degrade the accuracy of traditional navigation systems, but further impact the ability to successfully employ terrain-aided navigation. To address this problem, a tightly-coupled navigation is presented to successfully estimate the critical sensor errors by incorporating raw sensor data directly into an augmented navigation system. Furthermore, three-dimensional distance errors are calculated, providing measurement updates through the particle filter for absolute and bounded position error. The development of the terrain aided navigation system is elaborated for a vehicle equipped with a non-inertial-grade strapdown inertial navigation system, a 4-beam Doppler Velocity Log range sensor and a sonar altimeter. Using experimental data for navigation performance evaluation in areas with different terrain characteristics, the experiment results further show that the proposed method can be successfully applied to the low-cost AUVs and significantly improves navigation performance.

An Effective Terrain Aided Navigation for Low-Cost Autonomous Underwater Vehicles

PubMed Central

Zhou, Ling; Cheng, Xianghong; Zhu, Yixian; Dai, Chenxi; Fu, Jinbo

2017-01-01

Terrain-aided navigation is a potentially powerful solution for obtaining submerged position fixes for autonomous underwater vehicles. The application of terrain-aided navigation with high-accuracy inertial navigation systems has demonstrated meter-level navigation accuracy in sea trials. However, available sensors may be limited depending on the type of the mission. Such limitations, especially for low-grade navigation sensors, not only degrade the accuracy of traditional navigation systems, but further impact the ability to successfully employ terrain-aided navigation. To address this problem, a tightly-coupled navigation is presented to successfully estimate the critical sensor errors by incorporating raw sensor data directly into an augmented navigation system. Furthermore, three-dimensional distance errors are calculated, providing measurement updates through the particle filter for absolute and bounded position error. The development of the terrain aided navigation system is elaborated for a vehicle equipped with a non-inertial-grade strapdown inertial navigation system, a 4-beam Doppler Velocity Log range sensor and a sonar altimeter. Using experimental data for navigation performance evaluation in areas with different terrain characteristics, the experiment results further show that the proposed method can be successfully applied to the low-cost AUVs and significantly improves navigation performance. PMID:28346346

Institute of Navigation, Annual Meeting, 47th, Williamsburg, VA, June 10-12, 1991, Proceedings

NASA Astrophysics Data System (ADS)

1991-11-01

The present volume of navigation and exploration discusses space exploration, mapping and geodesy, aircraft navigation, undersea navigation, land and vehicular location, international and legal aspects of navigation, the history of navigation technology and applications, Loran development and implementation, GPS and GLONASS developments, and search and rescue. Topics addressed include stabilization of low orbiting spacecraft using GPS, the employment of laser navigation for automatic rendezvous and docking systems, enhanced pseudostatic processing, and the expanding role of sensor fusion. Attention is given to a gravity-aided inertial navigation system, recent developments in aviation products liability and navigation, the ICAO future air navigation system, and Loran's implementation in NAS. Also discussed are Inmarsat integrated navigation/communication activities, the GPS program status, the evolution of military GPS technology into the Navcore V receiver engine, and Sarsat location algorithms.

Bio-inspired polarized skylight navigation: a review

NASA Astrophysics Data System (ADS)

Zhang, Xi; Wan, Yongqin; Li, Lijing

2015-12-01

The idea of using skylight polarization in navigation is learned from animals such as desert ants and honeybees. Various research groups have been working on the development of novel navigation systems inspired by polarized skylight. The research of background in polarized skylight navigation is introduced, and basic principle of the insects navigation is expatiated. Then, the research progress status at home and abroad in skylight polarization pattern, three bio-inspired polarized skylight navigation sensors and polarized skylight navigation are reviewed. Finally, the research focuses in the field of polarized skylight navigation are analyzed. At the same time, the trend of development and prospect in the future are predicted. It is believed that the review is helpful to people understand polarized skylight navigation and polarized skylight navigation sensors.

Radar with Color-wrapped Height Fringes, Syracuse and vicinity, New York State

NASA Technical Reports Server (NTRS)

2000-01-01

This image shows the northern part of central New York State, a landscape sculpted by the ice sheets of the last ice age. Lake Ontario runs across the top of the image. The city of Syracuse is the radar-bright area next to the dark Onandaga Lake, below and to the right of the image center. The larger dark area on the right side is Oneida Lake. Several of the Finger Lakes are visible as long narrow dark patches on the left side of the image: Cayuga (north end only), Owasco, Skaneateles, and Otisco (left to right). The city of Auburn is at the north (top) end of Owasco Lake. Between 25,000 and 18,000 years ago, central New York was covered by a vast ice sheet 1,000-1,300 meters (3,300-4,300 feet) thick, similar to the one now covering Greenland. The land shows many marks left by the glaciers. Numerous small, elongated hills rise out of the plains south of Lake Ontario at the top and center of the image. These are drumlins, molded out of sand and clay at the bottom of the ice sheet. The shape of the drumlins indicates the direction that the ice sheet was moving and varies across the image, providing clues for scientists who study past climatic changes. The hills at the lower left of the image have been carved by the glaciers into 'U'-shaped valleys with steep sides and flat bottoms. In several places 'dry' valleys cross ridges without a modern river. These were probably carved at a time when the last stages of the glacier blocked rivers from flowing down the big valleys and forced the rivers to cut across the ridges. The wispy features along the shore of Lake Ontario are ice that was floating on the lake when SRTM acquired this image in February.

This image combines two types of data from the Shuttle Radar Topography Mission. The image brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation as measured by SRTM. Each cycle of colors (from red through green back to red) represents an equal amount of elevation difference similar to contour lines on a standard topographic map. Each color contour represents 100 meters of elevation change.

This image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

Size: 80 by 110 kilometers (50 by 70 miles) Location: 43.0 deg. North lat., 76.3 deg. West lon. Orientation: North toward the upper right Date Acquired: February 13, 2000

33 CFR 62.63 - Recommendations.

Code of Federal Regulations, 2013 CFR

2013-07-01

....63 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM Public Participation in the Aids to Navigation System § 62.63 Recommendations. (a) The public may recommend changes to existing aids to navigation, request new aids or the...

33 CFR 62.63 - Recommendations.

Code of Federal Regulations, 2014 CFR

2014-07-01

....63 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM Public Participation in the Aids to Navigation System § 62.63 Recommendations. (a) The public may recommend changes to existing aids to navigation, request new aids or the...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

33 CFR 183.810 - Navigation light certification requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Navigation light certification... SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Navigation Lights § 183.810 Navigation light certification requirements. (a) Except as provided by paragraph (b) of this section, each...

An integrated approach to the remote sensing of floating ice

NASA Technical Reports Server (NTRS)

Campbell, W. J.; Ramseier, R. O.; Weeks, W. F.; Gloersen, P.

1976-01-01

Review article on remote sensing applications to glaciology. Ice parameters sensed include: ice cover vs open water, ice thickness, distribution and morphology of ice formations, vertical resolution of ice thickness, ice salinity (percolation and drainage of brine; flushing of ice body with fresh water), first-year ice and multiyear ice, ice growth rate and surface heat flux, divergence of ice packs, snow cover masking ice, behavior of ice shelves, icebergs, lake ice and river ice; time changes. Sensing techniques discussed include: satellite photographic surveys, thermal IR, passive and active microwave studies, microwave radiometry, microwave scatterometry, side-looking radar, and synthetic aperture radar. Remote sensing of large aquatic mammals and operational ice forecasting are also discussed.

Cognitive Navigation: Toward a Biological Basis for Instructional Design.

ERIC Educational Resources Information Center

Tripp, Steven

2001-01-01

Discusses cognitive navigation, cognitive maps and online learning, and the role of the hippocampus in navigation. Topics include brain research in animal and human studies; types of memory; human navigation, including land navigation and information navigation; instructional strategies; tree maps of curriculum structure; cognitive complexity; and…

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2013 CFR

2013-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2012 CFR

2012-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 165.101 - Kittery, Maine-regulated navigation area.

Code of Federal Regulations, 2014 CFR

2014-07-01

... navigation area. 165.101 Section 165.101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.101 Kittery...

33 CFR 66.05-1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-1 Purpose. The purpose of the regulations in this subpart is to prescribe the conditions under which state governments may regulate aids to navigation owned...

33 CFR 66.10-1 - General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS..., the Uniform State Waterway Marking System's (USWMS) aids to navigation provisions for marking channels... waters for private aids to navigation and in those internal waters that are non-navigable waters of the U...

33 CFR 62.53 - Racons.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.53 Racons. (a) Aids to navigation may... non-laterally significant aids alike, the racon signal itself is for identification purposes only, and...

33 CFR 66.05-1 - Purpose.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-1 Purpose. The purpose of the regulations in this subpart is to prescribe the conditions under which state governments may regulate aids to navigation owned...

33 CFR 66.01-1 - Basic provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 66.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-1 Basic provisions. (a) The Uniform State Waterway Marking System's (USWMS) aids to navigation provisions for marking...

33 CFR 66.01-20 - Inspection.

Code of Federal Regulations, 2012 CFR

2012-07-01

....01-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-20 Inspection. All classes of private aids to navigation shall be maintained in proper operating condition. They are subject...

33 CFR 66.05-1 - Purpose.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-1 Purpose. The purpose of the regulations in this subpart is to prescribe the conditions under which state governments may regulate aids to navigation owned...

33 CFR 66.01-20 - Inspection.

Code of Federal Regulations, 2013 CFR

2013-07-01

....01-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-20 Inspection. All classes of private aids to navigation shall be maintained in proper operating condition. They are subject...

33 CFR 66.05-1 - Purpose.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-1 Purpose. The purpose of the regulations in this subpart is to prescribe the conditions under which state governments may regulate aids to navigation owned...

33 CFR 62.53 - Racons.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.53 Racons. (a) Aids to navigation may... non-laterally significant aids alike, the racon signal itself is for identification purposes only, and...

33 CFR 62.53 - Racons.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.53 Racons. (a) Aids to navigation may... non-laterally significant aids alike, the racon signal itself is for identification purposes only, and...

33 CFR 66.01-20 - Inspection.

Code of Federal Regulations, 2014 CFR

2014-07-01

....01-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-20 Inspection. All classes of private aids to navigation shall be maintained in proper operating condition. They are subject...

33 CFR 66.01-20 - Inspection.

Code of Federal Regulations, 2011 CFR

2011-07-01

....01-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-20 Inspection. All classes of private aids to navigation shall be maintained in proper operating condition. They are subject...

33 CFR 72.01-1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Purpose. 72.01-1 Section 72.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARINE... establishment of aids to maritime navigation and the changes, discontinuances, and deficiencies, except...

33 CFR 72.01-1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Purpose. 72.01-1 Section 72.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION MARINE... establishment of aids to maritime navigation and the changes, discontinuances, and deficiencies, except...

33 CFR 165.827 - Regulated Navigation Area; Galveston Channel, TX.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Regulated Navigation Area... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Eighth Coast Guard District § 165.827...

33 CFR 165.827 - Regulated Navigation Area; Galveston Channel, TX.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Regulated Navigation Area... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Eighth Coast Guard District § 165.827...

33 CFR 66.01-20 - Inspection.

Code of Federal Regulations, 2010 CFR

2010-07-01

....01-20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-20 Inspection. All classes of private aids to navigation shall be maintained in proper operating condition. They are subject...

33 CFR 66.05-1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-1 Purpose. The purpose of the regulations in this subpart is to prescribe the conditions under which state governments may regulate aids to navigation owned...

33 CFR 66.10-1 - General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS..., the Uniform State Waterway Marking System's (USWMS) aids to navigation provisions for marking channels... waters for private aids to navigation and in those internal waters that are non-navigable waters of the U...

33 CFR 66.01-1 - Basic provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 66.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-1 Basic provisions. (a) The Uniform State Waterway Marking System's (USWMS) aids to navigation provisions for marking...

33 CFR 67.01-30 - Equivalents.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Equivalents. 67.01-30 Section 67.01-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements § 67.01-30...

33 CFR 67.01-15 - Classification of structures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Classification of structures. 67.01-15 Section 67.01-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements...

33 CFR 67.10-10 - Operating requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Operating requirements. 67.10-10 Section 67.10-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements for Sound...

33 CFR 67.01-30 - Equivalents.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Equivalents. 67.01-30 Section 67.01-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements § 67.01-30...

33 CFR 67.10-10 - Operating requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Operating requirements. 67.10-10 Section 67.10-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements for Sound...

33 CFR 67.10-5 - Location requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Location requirements. 67.10-5 Section 67.10-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements for Sound...

33 CFR 67.05-25 - Special lighting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Special lighting requirements. 67.05-25 Section 67.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements...

33 CFR 67.05-25 - Special lighting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Special lighting requirements. 67.05-25 Section 67.05-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION AIDS TO NAVIGATION ON ARTIFICIAL ISLANDS AND FIXED STRUCTURES General Requirements...

The Relationships between Navigational Patterns and Informational Processing Styles of Hypermedia Users.

ERIC Educational Resources Information Center

Lee, Mi Jar; Harvey, Francis A.

This study investigated the relationships between hypermedia users' information processing styles and navigational patterns. Three aspects of navigational patterns were investigated: navigational depth patterns that reveal how comprehensively users access; navigational path patterns that display what sequences users follow; and navigational method…

14 CFR 121.389 - Flight navigator and specialized navigation equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight navigator and specialized navigation equipment. 121.389 Section 121.389 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an...

14 CFR 121.389 - Flight navigator and specialized navigation equipment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Flight navigator and specialized navigation equipment. 121.389 Section 121.389 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF....389 Flight navigator and specialized navigation equipment. (a) No certificate holder may operate an...

Review of crop growth and soil moisture monitoring from a ground-based instrument implementing the Interference Pattern GNSS-R Technique

NASA Astrophysics Data System (ADS)

Rodriguez-Alvarez, N.; Bosch-Lluis, X.; Camps, A.; Aguasca, A.; Vall-Llossera, M.; Valencia, E.; Ramos-Perez, I.; Park, H.

2011-12-01

Reflectometry using Global Navigation Satellite Systems signals (GNSSR) has been the focus of many studies during the past few years for a number of applications over different scenarios as land, ocean or snow and ice surfaces. In the past decade, its potential has increased yearly, with improved receivers and signal processors, from generic GNSS receivers whose signals were recorded in magnetic tapes to instruments that measure full Delay Doppler Maps (the power distribution of the reflected GNSS signal over the 2-D space of delay offsets and Doppler shifts) in real time. At present, these techniques are considered to be promising tools to retrieve geophysical parameters such as soil moisture, vegetation height, topography, altimetry, sea state and ice and snow thickness, among others. This paper focuses on the land geophysical retrievals (topography, vegetation height and soil moisture) performed from a ground-based instrument using the Interference Pattern Technique (IPT). This technique consists of the measurement of the power fluctuations of the interference signal resulting from the simultaneous reception of the direct and the reflected GNSS signals. The latest experiment performed using this technique over a maize field is shown in this paper. After a review of the previous results, this paper presents the latest experiment performed using this technique over a maize field. This new study provides a deeper analysis on the soil moisture retrieval by observing three irrigation-drying cycles and comparing them to different depths soil moisture probes. Furthermore, the height of the maize, almost 300 cm, has allowed testing the capabilities of the technique over dense and packed vegetation layers, with high vegetation water content.

Development of an Unmanned Aircraft Systems Program: ACUASI

NASA Astrophysics Data System (ADS)

Webley, P. W.; Cahill, C. F.; Rogers, M.; Hatfield, M. C.

2017-12-01

The Alaska Center for Unmanned Aircraft Systems Integration (ACUASI) has developed a comprehensive program that incorporates pilots, flight/mission planners, geoscientists, university undergraduate and graduate students, and engineers together as one. We lead and support unmanned aircraft system (UAS) missions for geoscience research, emergency response, humanitarian needs, engineering design, and policy development. We are the University of Alaska's UAS research program, lead the Federal Aviation Administration (FAA) Pan-Pacific UAS Test Range Complex (PPUTRC) with Hawaii, Oregon, and Mississippi and in 2015 became a core member of the FAA Center of Excellence for UAS Research, managed by Mississippi State University. ACUASI's suite of aircraft include small hand-launched/vertical take-off and landing assets for short-term rapid deployment to large fixed-wing gas powered systems that provide multiple hours of flight time. We have extensive experience in Arctic and sub-Arctic environments and will present on how we have used our aircraft and payloads in numerous missions that include beyond visual line of sight flights, mapping the river ice-hazard in Alaska during spring break-up, and providing UAS-based observations for local Alaskans to navigate through the changing ice shelf of Northern Alaska. Several sensor developments of interest in the near future include building payloads for thermal infrared mapping at high spatial resolutions, combining forward and nadir looking cameras on the same UAS aircraft for topographic mapping, and using neutral density and narrow band filters to map very high temperature thermally active hazards, such as forest fires and volcanic eruptions. The ACUASI team working together provide us the experience, tools, capabilities, and personnel to build and maintain a world class research center for unmanned aircraft systems as well as support both real-time operations and geoscience research.

Integration of intracardiac echocardiography and computed tomography during atrial fibrillation ablation: Combining ultrasound contours obtained from the right atrium and ventricular outflow tract.

PubMed

Nakamura, Kohki; Naito, Shigeto; Kaseno, Kenichi; Nakatani, Yosuke; Sasaki, Takehito; Anjo, Naofumi; Yamashita, Eiji; Kumagai, Koji; Funabashi, Nobusada; Kobayashi, Yoshio; Oshima, Shigeru

2017-02-01

We aimed to optimize the acquisition of the left atrial (LA) and pulmonary vein (PV) ultrasound contours for more accurate integration of intracardiac echocardiography (ICE) and computed tomography (CT) using the CARTO ® 3 system during atrial fibrillation (AF) ablation. Eighty-five AF patients underwent integration of ICE and CT using (1) the LA roof and posterior wall contours acquired from the right atrium (RA), (2) all LA/PV contours from the RA (Whole-RA-integration), (3) the LA roof/posterior wall contours from the RA and right ventricular outflow tract (RVOT) (Posterior-RA/RV-integration), and (4) all LA/PV contours from the RA and RVOT (Whole-RA/RV-integration). The integration accuracy was compared using the (1) surface registration error, (2) distances between the three-dimensional CT and eight specific sites on the anterior, posterior, superior, and inferior aspects of the right and left circumferential PV isolation lines, and (3) registration score: a score of 0 or 1 was assigned for whether or not each specific site was visually aligned with the CT, and summed for each method (0 best, 8 worst). Posterior-RA/RV-integration revealed a significantly lower surface registration error (1.30±0.15mm) than Whole-RA- and Whole-RA/RV-integration (p<0.001). The mean distances of the eight specific sites and the registration score for Posterior-RA/RV-integration (median 1.26mm and 2, respectively) were significantly smaller than those for the other integration approaches (p<0.001). Image integration with the LA roof and posterior wall contours acquired from the RA and RVOT may provide greater accuracy for catheter navigation with three-dimensional CT during AF ablation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Aircraft Weather Mitigation for the Next Generation Air Transportation System

NASA Technical Reports Server (NTRS)

Stough, H. Paul, III

2007-01-01

Atmospheric effects on aviation are described by Mahapatra (1999) as including (1) atmospheric phenomena involving air motion - wind shear and turbulence; (2) hydrometeorological phenomena - rain, snow and hail; (3) aircraft icing; (4) low visibility; and (5) atmospheric electrical phenomena. Aircraft Weather Mitigation includes aircraft systems (e.g. airframe, propulsion, avionics, controls) that can be enacted (by a pilot, automation or hybrid systems) to suppress and/or prepare for the effects of encountered or unavoidable weather or to facilitate a crew operational decision-making process relative to weather. Aircraft weather mitigation can be thought of as a continuum (Figure 1) with the need to avoid all adverse weather at one extreme and the ability to safely operate in all weather conditions at the other extreme. Realistic aircraft capabilities fall somewhere between these two extremes. The capabilities of small general aviation aircraft would be expected to fall closer to the "Avoid All Adverse Weather" point, and the capabilities of large commercial jet transports would fall closer to the "Operate in All Weather Conditions" point. The ability to safely operate in adverse weather conditions is dependent upon the pilot s capabilities (training, total experience and recent experience), the airspace in which the operation is taking place (terrain, navigational aids, traffic separation), the capabilities of the airport (approach guidance, runway and taxiway lighting, availability of air traffic control), as well as the capabilities of the airplane. The level of mitigation may vary depending upon the type of adverse weather. For example, a small general aviation airplane may be equipped to operate "in the clouds" without outside visual references, but not be equipped to prevent airframe ice that could be accreted in those clouds.

Evaluation of potential impacts on Great Lakes water resources based on climate scenarios of two GCMs

USGS Publications Warehouse

Lofgren, B.M.; Quinn, F.H.; Clites, A.H.; Assel, R.A.; Eberhardt, A.J.; Luukkonen, C.L.

2002-01-01

The results of general circulation model predictions of the effects of climate change from the Canadian Centre for Climate Modeling and Analysis (model CGCM1) and the United Kingdom Meteorological Office's Hadley Centre (model HadCM2) have been used to derive potential impacts on the water resources of the Great Lakes basin. These impacts can influence the levels of the Great Lakes and the volumes of channel flow among them, thus affecting their value for interests such as riparians, shippers, recreational boaters, and natural ecosystems. On one hand, a hydrological modeling suite using input data from the CGCM1 predicts large drops in lake levels, up to a maximum of 1.38 m on Lakes Michigan and Huron by 2090. This is due to a combination of a decrease in precipitation and an increase in air temperature that leads to an increase in evaporation. On the other hand, using input from HadCM2, rises in lake levels are predicted, up to a maximum of 0.35 m on Lakes Michigan and Huron by 2090, due to increased precipitation and a reduced increase in air temperature. An interest satisfaction model shows sharp decreases in the satisfaction of the interests of commercial navigation, recreational boating, riparians, and hydropower due to lake level decreases. Most interest satisfaction scores are also reduced by lake level increases. Drastic reductions in ice cover also result from the temperature increases such that under the CGCM1 predictions, most of Lake Erie has 96% of its winters ice-free by 2090. Assessment is also made of impacts on the groundwater-dependent region of Lansing, Michigan.

33 CFR 66.01-10 - Characteristics.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 66.01-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-10... States Aids to Navigation System set forth in subpart B of part 62 of this subchapter. [USCG-2000-7466...

33 CFR 100.45 - Establishment of aids to navigation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary to...

33 CFR 66.10-1 - General.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS... Marking System's (USWMS) aids to navigation provisions for marking channels and obstructions (see § 66.10... private aids to navigation and in those internal waters that are non-navigable waters of the U.S. All...

33 CFR 66.10-1 - General.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS... Marking System's (USWMS) aids to navigation provisions for marking channels and obstructions (see § 66.10... private aids to navigation and in those internal waters that are non-navigable waters of the U.S. All...

33 CFR 66.01-10 - Characteristics.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 66.01-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-10... States Aids to Navigation System set forth in subpart B of part 62 of this subchapter. [USCG-2000-7466...

33 CFR 66.01-10 - Characteristics.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 66.01-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-10... States Aids to Navigation System set forth in subpart B of part 62 of this subchapter. [USCG-2000-7466...

33 CFR 62.1 - Purpose.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM General § 62.1 Purpose. (a) The Coast Guard administers the U.S. Aids to Navigation System. The system consists of Federal aids to navigation operated by the Coast Guard, aids to...

33 CFR 100.45 - Establishment of aids to navigation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Establishment of aids to... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.45 Establishment of aids to navigation. The District Commander will establish and maintain only those aids to navigation necessary to...

33 CFR 66.05-30 - Notice to Mariners.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Section 66.05-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-30 Notice to Mariners. (a) To improve public safety, the District Commander may publish information concerning State aids to navigation...

33 CFR 66.01-10 - Characteristics.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 66.01-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-10... States Aids to Navigation System set forth in subpart B of part 62 of this subchapter. [USCG-2000-7466...

33 CFR 62.1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM General § 62.1 Purpose. (a) The Coast Guard administers the U.S. Aids to Navigation System. The system consists of Federal aids to navigation operated by the Coast Guard, aids to...

33 CFR 66.01-1 - Basic provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 66.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-1 Basic... the purposes of this subpart, the term private aids to navigation includes all marine aids to...

33 CFR 66.05-30 - Notice to Mariners.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Section 66.05-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-30 Notice to Mariners. (a) To improve public safety, the District Commander may publish information concerning State aids to navigation...

33 CFR 66.01-1 - Basic provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 66.01-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-1 Basic... the purposes of this subpart, the term private aids to navigation includes all marine aids to...

33 CFR 62.54 - Ownership identification.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Section 62.54 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.54 Ownership identification. Ownership identification on private or state aids to navigation is permitted so long as it does...

33 CFR 66.01-25 - Discontinuance and removal.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-25 Section 66.01-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-25... establishment of the aid was submitted. (c) Private aids to navigation which have been authorized pursuant to...

33 CFR 66.01-25 - Discontinuance and removal.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-25 Section 66.01-25 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION Aids to Navigation Other Than Federal or State § 66.01-25... establishment of the aid was submitted. (c) Private aids to navigation which have been authorized pursuant to...

33 CFR 66.05-30 - Notice to Mariners.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Section 66.05-30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-30 Notice to Mariners. (a) To improve public safety, the District Commander may publish information concerning State aids to navigation...

33 CFR 62.54 - Ownership identification.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Section 62.54 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.54 Ownership identification. Ownership identification on private or state aids to navigation is permitted so long as it does...