2012-09-30
International Arctic Buoy Programme ( IABP ) A US Interagency Arctic Buoy Programme (USIABP) contribution to the IABP Dr. Ignatius G. Rigor Polar...observations of surface meteorology and ice motion. These observations are assimilated into Numerical Weather Prediction (NWP) models that are used to...distribution of sea ice. Over the Arctic Ocean, this fundamental observing network is maintained by the IABP , and is a critical component of the
2013-09-30
data from the IABP ); 2.) Forecasting weather and sea ice conditions; 3.) Forcing, assimilation and validation of global weather and climate models ...International Arctic Buoy Programme ( IABP ) A US Interagency Arctic Buoy Programme (USIABP) contribution to the IABP Dr. Ignatius G. Rigor Polar...ice motion. These observations are assimilated into Numerical Weather Prediction (NWP) models that are used to forecast weather on synoptic time
The International Arctic Buoy Programme (IABP): A Cornerstone of the Arctic Observing Network
2008-09-01
SEP 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE The International Arctic Buoy Programme ( IABP ): A...Prescribed by ANSI Std Z39-18 The International Arctic Buoy Programme ( IABP ): A Cornerstone of the Arctic Observing Network Ignatius G. Rigor...changes in weather, climate and environment. It should be noted that many of these changes were first observed and studied using data from the IABP (http
The International Arctic Buoy Programme (IABP) - An International Polar Year Every Year
NASA Astrophysics Data System (ADS)
Hanna, M.; Rigor, I.; Ortmeyer, M.; Haas, C.
2004-12-01
A network of automatic data buoys to monitor synoptic-scale fields of sea level pressure (SLP), surface air temperature (SAT), and ice motion throughout the Arctic Ocean was recommended by the U.S. National Academy of Sciences in 1974. Based on the Academy's recommendation, the Arctic Ocean Buoy Program was established by the Polar Science Center, Applied Physics Laboratory (APL), University of Washington, in 1978 to support the Global Weather Experiment. Operations began in early 1979, and the program continued through 1990 under funding from various agencies. In 1991, the International Arctic Buoy Programme (IABP) succeeded the Arctic Ocean Buoy Program, but the basic objective remains - to maintain a network of drifting buoys on the Arctic Ocean to provide meteorological and oceanographic data for real-time operational requirements and research purposes including support to the World Climate Research Programme and the World Weather Watch Programme. The IABP currently has 37 buoys deployed on the Arctic Ocean. Most of the buoys measure SLP and SAT, but many buoys are enhanced to measure other geophysical variables such as sea ice thickness, ocean temperature and salinity. This observational array is maintained by the 20 Participants from 10 different countries, who support the program through contributions of buoys, deployment logistics, and other services. The observations from the IABP are posted on the Global Telecommunications System for operational use, are archived at the World Data Center for Glaciology at the National Snow and Ice Data Center (http://nsidc.org), and can also be obtained from the IABP web server for research (http://iabp.apl.washington.edu). The observations from the IABP have been essential for: 1.) Monitoring Arctic and global climate change; 2.) Forecasting weather and sea ice conditions; 3.) Forcing, assimilation and validation of global weather and climate models; 4.) Validation of satellite data; etc. As of 2003, over 450 papers have been written using the observations collected by the IABP. The observations from IABP have been one of the cornerstones for environmental forecasting and studies of climate and climate change, i.e. many of the changes in Arctic climate were first observed or explained using data from the IABP. The IABP is also evolving to better support the operational and research requirements of the community. For example, some of the Participants of the IABP have been deploying buoys which not only measure SLP and SAT, but also ocean currents, temperatures and salinity. Other buoys have been enhanced to measure the ice mass balance (IMB) using thermistor strings and pingers aimed at the top and bottom of the sea ice. Some of these ocean and IMB buoys are deployed in close proximity to each other in order to provide a myriad of concurrent observations at a few points across the Arctic Ocean. From these data we can also estimate time variations in other geophysical variables such as oceanic heat storage and heat flux. These stations provide critical atmospheric, ice, and upper ocean hydrographic measurements that cannot be obtained by other means. The Arctic and global climate system is changing. These changes threaten our native cultures and ecosystems, but may also provide economic and social opportunities. In order to understand and respond to these changes, we need to sustain our current observational systems, and for the Arctic, the IABP provides the longest continuing record of observations.
Coordination and Data Management of the International Arctic Buoy Programme (IABP)
2002-09-30
for forcing, validation and assimilation into numerical climate models , and for forecasting weather and ice conditions. TRANSITIONS Using IABP ...Coordination and Data Management of the International Arctic Buoy Programme ( IABP ) Ignatius G. Rigor 1013 NE 40th Street Polar Science Center...analyzed geophysical fields. APPROACH The IABP is a collaboration between 25 different institutions from 8 different countries, which work together
Coordination and Data Management of the International Arctic Buoy Programme (IABP)
1998-01-01
estimate the mean surface wind, which can drive sea ice models , and for input into climate change studies. Recent research using the IABP databases includes...Coordination and Data Management of the International Arctic Buoy Programme ( IABP ) Ignatius G. Rigor Polar Science Center, Applied Physics Laboratory...the National Center for Environmental Projection underlayed. APPROACH Coordination of the IABP involves distribution of information, resource
Coordination and Data Management of the International Arctic Buoy Programme (IABP)
2001-09-30
Coordination and Data Management of the International Arctic Buoy Programme ( IABP ) Ignatius G. Rigor 1013 NE 40th Street Polar Science Center...analyzed geophysical fields. APPROACH Coordination of the IABP falls into the categories of information, resource management, and meeting...the Polar Science Center (PSC) via anonymous ftp. These data and other research products of the IABP are available on the World Wide Web at http
Coordination and Data Management of the International Arctic Buoy Programme (IABP)
1999-09-30
Coordination and Data Management of the International Arctic Buoy Programme ( IABP ) Ignatius G. Rigor 1013 NE 40th Street Polar Science Center...Coordination of the IABP falls into the categories of information, resource management, and meeting planning. Information is primarily distributed via a...These data and other research products of the IABP are available on the World Wide Web at http://iabp.apl.washington.edu/. WORK COMPLETED Our recent
Coordination and Data Management of the International Arctic Buoy Programme (IABP)
2000-09-30
Coordination and Data Management of the International Arctic Buoy Programme ( IABP ) Ignatius G. Rigor 1013 NE 40th Street Polar Science Center...Coordination of the IABP falls into the categories of information, resource management, and meeting planning. Information is primarily distributed via a monthly...data and other research products of the IABP are available on the World Wide Web at http://iabp.apl.washington.edu/. Report Documentation Page Form
NASA Astrophysics Data System (ADS)
Rigor, I. G.; Clemente-Colon, P.; Nghiem, S. V.; Hall, D. K.; Woods, J. E.; Henderson, G. R.; Zook, J.; Marshall, C.; Gallage, C.
2014-12-01
The Arctic environment has been undergoing profound changes; the most visible is the dramatic decrease in Arctic sea ice extent (SIE). These changes pose a challenge to our ability to measure surface temperature across the Polar Regions. Traditionally, the International Arctic Buoy Programme (IABP) and International Programme for Antarctic Buoys (IPAB) have measured surface air temperature (SAT) at 2-m height, which minimizes the ambiguity of measurements near of the surface. Specifically, is the temperature sensor measuring open water, snow, sea ice, or air? But now, with the dramatic decrease in Arctic SIE, increase in open water during summer, and the frailty of the younger sea ice pack, the IABP has had to deploy and develop new instruments to measure temperature. These instruments include Surface Velocity Program (SVP) buoys, which are commonly deployed on the world's ice-free oceans and typically measure sea surface temperature (SST), and the new robust Airborne eXpendable Ice Beacons (AXIB), which measure both SST and SAT. "Best Practice" requires that these instruments are inter-compared, and early results showing differences in collocated temperature measurements of over 2°C prompted the establishment of the IABP Arctic Observing Experiment (AOX) buoy test site at the US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) site in Barrow, Alaska. Preliminary results showed that the color of the hull of SVP buoys introduces a bias due to solar heating of the buoy. Since then, we have recommended that buoys should be painted white to reduce biases in temperature measurements due to different colors of the buoys deployed in different regions of the Arctic or the Antarctic. Measurements of SAT are more robust, but some of the temperature shields are susceptible to frosting. During our presentation we will provide an intercomparison of the temperature measurements at the AOX test site (i.e. high quality DOE/ARM observations compared with unattended buoy measurements, and satellite retrievals). We will also show how these data may be used to improve our record of temperature over polar environments.
The International Arctic Buoy Programme (IABP)
NASA Astrophysics Data System (ADS)
Rigor, I. G.; Ortmeyer, M.
2003-12-01
The Arctic has undergone dramatic changes in weather, climate and environment. It should be noted that many of these changes were first observed and studied using data from the International Arctic Buoy Programme (IABP). For example, IABP data were fundamental to Walsh et al. (1996) showing that atmospheric pressure has decreased, Rigor et al. (2000) showing that air temperatures have increased, and to Proshutinsky and Johnson (1997); Steele and Boyd, (1998); Kwok, (2000); and Rigor et al. (2002) showing that the clockwise circulation of sea ice and the ocean has weakened. All these results relied heavily on data from the IABP. In addition to supporting these studies of climate change, the IABP observations are also used to forecast weather and ice conditions, validate satellite retrievals of environmental variables, to force, validate and initialize numerical models. Over 350 papers have been written using data from the IABP. The observations and datasets of the IABP data are one of the cornerstones for environmental forecasting and research in the Arctic.
United States Naval Academy Polar Science Program's Visual Arctic Observing Buoys; The IceGoat
NASA Astrophysics Data System (ADS)
Woods, J. E.; Clemente-Colon, P.; Nghiem, S. V.; Rigor, I.; Valentic, T. A.
2012-12-01
The U.S. Naval Academy Oceanography Department currently has a curriculum based Polar Science Program (USNA PSP). Within the PSP there is an Arctic Buoy Program (ABP) student research component that will include the design, build, testing and deployment of Arctic Buoys. Establishing an active, field-research program in Polar Science will greatly enhance Midshipman education and research, as well as introduce future Naval Officers to the Arctic environment. The Oceanography Department has engaged the USNA Ocean Engineering, Systems Engineering, Aerospace Engineering, and Computer Science Departments and developed a USNA Visual Arctic Observing Buoy, IceGoat1, which was designed, built, and deployed by midshipmen. The experience gained through Polar field studies and data derived from these buoys will be used to enhance course materials and laboratories and will also be used directly in Midshipman independent research projects. The USNA PSP successfully deployed IceGoat1 during the BROMEX 2012 field campaign out of Barrow, AK in March 2012. This buoy reports near real-time observation of Air Temperature, Sea Temperature, Atmospheric Pressure, Position and Images from 2 mounted webcams. The importance of this unique type of buoy being inserted into the U.S. Interagency Arctic Buoy Program and the International Arctic Buoy Programme (USIABP/IABP) array is cross validating satellite observations of sea ice cover in the Arctic with the buoys webcams. We also propose to develop multiple sensor packages for the IceGoat to include a more robust weather suite, and a passive acoustic hydrophone. Remote cameras on buoys have provided crucial qualitative information that complements the quantitative measurements of geophysical parameters. For example, the mechanical anemometers on the IABP Polar Arctic Weather Station at the North Pole Environmental Observatory (NPEO) have at times reported zero winds speeds, and inspection of the images from the NPEO cameras have showed frosting on the camera during these same periods indicating that the anemometer has temporarily frozen up. Later when the camera lens clears, the anemometers resume providing reasonable wind speeds. The cameras have also provided confirmation of the onset of melt and freeze, and indications of cloudy and clear skies. USNA PSP will monitor meteorological and oceanographic parameters of the Arctic environment remotely via its own buoys. Web cameras will provide near real time visual observations of the buoys current positions, allowing for instant validation of other remotes sensors and modeled data. Each buoy will be developed with at a minimum a meteorological sensor package in accordance with IABP protocol (2m Air Temp, SLP). Platforms will also be developed with new sensor packages to possibly include, wind speed, ice temperature, sea ice thickness, underwater acoustics, and new communications suites (Iridium, Radio). The uniqueness of the IceGoat is that it is based on the new AXIB buoy designed by LBI, Inc. that has a proven record of being able to survive in the harsh marginal ice zone environment. IceGoat1 will be deployed in the High Arctic during the USCGC HEALY cruise in late August 2012.
NASA Astrophysics Data System (ADS)
Moritz, R. E.; Rigor, I.
2006-12-01
ABSTRACT: The Arctic Buoy Program was initiated in 1978 to measure surface air pressure, surface temperature and sea-ice motion in the Arctic Ocean, on the space and time scales of synoptic weather systems, and to make the data available for research, forecasting and operations. The program, subsequently renamed the International Arctic Buoy Programme (IABP), has endured and expanded over the past 28 years. A hallmark of the IABP is the production, dissemination and archival of research-quality datasets and analyses. These datasets have been used by the authors of over 500 papers on meteorolgy, sea-ice physics, oceanography, air-sea interactions, climate, remote sensing and other topics. Elements of the IABP are described briefly, including measurements, analysis, data dissemination and data archival. Selected highlights of the research applications are reviewed, including ice dynamics, ocean-ice modeling, low-frequency variability of Arctic air-sea-ice circulation, and recent changes in the age, thickness and extent of Arctic Sea-ice. The extended temporal coverage of the data disseminated on the Environmental Working Group CD's is important for interpreting results in the context of climate.
NASA Astrophysics Data System (ADS)
Hoppmann, Mario; Nicolaus, Marcel; Rabe, Benjamin; Wenzhöfer, Frank; Katlein, Christian; Scholz, Daniel
2016-04-01
The Arctic Ocean has been in the focus of many studies during recent years, investigating the state, the causes and the implications of the observed rapid transition towards a thinner and younger sea-ice cover. However, consistent observational datasets of sea ice, ocean and atmosphere are still sparse due to the limited accessibility and harsh environmental conditions. One important tool to fill this gap has become more and more feasible during recent years: autonomous, ice-tethered measurement platforms (buoys). These drifting instruments independently transmit their data via satellites, and enable observations over larger areas and over longer time periods than manned expeditions, even throughout the winter. One aim of the newly established FRAM (FRontiers in Arctic marine Monitoring) infrastructure program at the Alfred-Wegener-Institute is to realize and maintain an interdisciplinary network of buoys in the Arctic Ocean, contributing to an integrated, Arctic-wide observatory. The additional buoy infrastructure, ship-time, and developments provided by FRAM are critical elements in the ongoing international effort to fill the large data gaps in a rapidly changing Arctic Ocean. Our focus is the particularly underrepresented Eurasian Basin. Types of instruments range from snow depth beacons and ice mass balance buoys for monitoring ice growth and snow accumulation, over radiation and weather stations for energy budget estimates, to ice-tethered profiling systems for upper ocean monitoring. Further, development of new bio-optical and biogeochemical buoys is expected to enhance our understanding of bio-physical processes associated with Arctic sea ice. The first set of FRAM buoys was deployed in September 2015 from RV Polarstern. All datasets are publicly available on dedicated web portals. Near real time data are reported into international initiatives, such as the Global Telecommunication System (GTS) and the International Arctic Buoy Programme (IABP). The additional data acquired by FRAM buoys facilitate the validation of model results and remote sensing products, play an important role in understanding the linkages between the atmosphere, sea ice and upper ocean, and help assess the physical, biological and biogeochemical states of the future Arctic Ocean. Here we present our recent work and future plans, but are also aiming for additional collaborations, especially on technical developments, scientific questions and deployment logistics.
Arctic Observing Experiment (AOX) Field Campaign Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rigor, Ignatius; Johnson, Jim; Motz, Emily
Our ability to understand and predict weather and climate requires an accurate observing network. One of the pillars of this network is the observation of the fundamental meteorological parameters: temperature, air pressure, and wind. We plan to assess our ability to measure these parameters for the polar regions during the Arctic Observing Experiment (AOX, Figure 1) to support the International Arctic Buoy Programme (IABP), Arctic Observing Network (AON), International Program for Antarctic Buoys (IPAB), and Southern Ocean Observing System (SOOS). Accurate temperature measurements are also necessary to validate and improve satellite measurements of surface temperature across the Arctic. Support formore » research associated with the campaign is provided by the National Science Foundation, and by other US agencies contributing to the US Interagency Arctic Buoy Program. In addition to the support provided by the U.S Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s North Slope of Alaska (NSA) site at Barrow and the National Science Foundation (NSF), the U.S. IABP is supported by the U.S. Coast Guard (USCG), the National Aeronautics and Space Administration (NASA), the National Ice Center (NIC), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR).« less
Snow depth on Arctic and Antarctic sea ice derived from autonomous (Snow Buoy) measurements
NASA Astrophysics Data System (ADS)
Nicolaus, Marcel; Arndt, Stefanie; Hendricks, Stefan; Heygster, Georg; Huntemann, Marcus; Katlein, Christian; Langevin, Danielle; Rossmann, Leonard; Schwegmann, Sandra
2016-04-01
The snow cover on sea ice received more and more attention in recent sea ice studies and model simulations, because its physical properties dominate many sea ice and upper ocean processes. In particular; the temporal and spatial distribution of snow depth is of crucial importance for the energy and mass budgets of sea ice, as well as for the interaction with the atmosphere and the oceanic freshwater budget. Snow depth is also a crucial parameter for sea ice thickness retrieval algorithms from satellite altimetry data. Recent time series of Arctic sea ice volume only use monthly snow depth climatology, which cannot take into account annual changes of the snow depth and its properties. For Antarctic sea ice, no such climatology is available. With a few exceptions, snow depth on sea ice is determined from manual in-situ measurements with very limited coverage of space and time. Hence the need for more consistent observational data sets of snow depth on sea ice is frequently highlighted. Here, we present time series measurements of snow depths on Antarctic and Arctic sea ice, recorded by an innovative and affordable platform. This Snow Buoy is optimized to autonomously monitor the evolution of snow depth on sea ice and will allow new insights into its seasonality. In addition, the instruments report air temperature and atmospheric pressure directly into different international networks, e.g. the Global Telecommunication System (GTS) and the International Arctic Buoy Programme (IABP). We introduce the Snow Buoy concept together with technical specifications and results on data quality, reliability, and performance of the units. We highlight the findings from four buoys, which simultaneously drifted through the Weddell Sea for more than 1.5 years, revealing unique information on characteristic regional and seasonal differences. Finally, results from seven snow buoys co-deployed on Arctic sea ice throughout the winter season 2015/16 suggest the great importance of local effects, weather events, and potential influences of dynamic sea ice processes on snow accumulation.
U.S. National / Naval Ice Center (NIC) Support to Naval and Maritime Operations
2011-06-20
States and Canadian governments. • International Arctic Buoy Programme ( IABP ) Global participants working together to maintain a network of... Modeling Surface Observations Satellite Air Recon Data Fusion Derived Data Automation Direct Data Dissemination TODAY’S CHALLENGES...and AUVs • Improve modeling and forecasting capabilities (OTSR/WEAX) • More trained ice analysts, ice pilots, and Arctic marine weather forecasters
NASA Astrophysics Data System (ADS)
Hoppmann, Mario; Nicolaus, Marcel; Rabe, Benjamin; Wenzhöfer, Frank; Katlein, Christian; Scholz, Daniel; Valcic, Lovro
2017-04-01
To understand the current evolution of the Arctic Ocean towards a less extensive, thinner and younger sea ice cover is one of the biggest challenges in climate research. Especially the lack of simultaneous in-situ observations of sea ice, ocean and atmospheric properties leads to significant knowledge gaps in their complex interactions, and how the associated processes impact the polar marine ecosystem. Here we present a concept for the implementation of a long-term strategy to monitor the most essential climate- and ecosystem parameters in the central Arctic Ocean, year round and synchronously. The basis of this strategy is the development and enhancement of a number of innovative autonomous observational platforms, such as rugged weather stations, ice mass balance buoys, ice-tethered bio-optical buoys and upper ocean profilers. The deployment of those complementing platforms in a distributed network enables the simultaneous collection of physical and biogeochemical in-situ data on basin scales and year round, including the largely undersampled winter periods. A key advantage over other observatory systems is that the data is sent via satellite in near-real time, contributing to numerical weather predictions through the Global Telecommunication System (GTS) and to the International Arctic Buoy Programme (IABP). The first instruments were installed on ice floes in the Eurasian Basin in spring 2015 and 2016, yielding exceptional records of essential climate- and ecosystem-relevant parameters in one of the most inaccessible regions of this planet. Over the next 4 years, and including the observational periods of the Year of Polar Prediction (YOPP, 2017-2019) and the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC, 2020), the distributed observatory will be maintained by deployment of additional instruments in the central Arctic each year, benefitting from international logistical efforts.
NASA Astrophysics Data System (ADS)
Matrai, P.
2016-02-01
Autonomous, sea ice-tethered O-Buoys have been deployed (2009-2016) across the Arctic sea ice for long-term atmospheric measurements (http://www.o-buoy.org). O-Buoys (15) provide in-situ concentrations of three sentinel atmospheric chemicals, ozone, CO2 and BrO, as well as meteorological parameters and imagery, over the frozen ocean. O-Buoys were designed to transmit daily data over a period of 2 years while deployed in sea ice, as part of automated ice-drifting stations that include snow/ice measurement systems (e.g. Ice Mass Balance buoys) and oceanographic measurements (e.g. Ice Tethered Profilers). Seasonal changes in Arctic atmospheric chemistry are influenced by changes in the characteristics and presence of the sea ice vs. open water as well as air mass trajectories, especially during the winter-spring and summer-fall transitions when sea ice is melting and freezing, respectively. The O-Buoy Chemical Network provides the unique opportunity to observe these transition periods in real-time with high temporal resolution, and to compare them with those collected on land-based monitoring stations located. Due to the logistical challenges of measurements over the Arctic Ocean region, most long term, in-situ observations of atmospheric chemistry have been made at coastal or island sites around the periphery of the Arctic Ocean, leaving large spatial and temporal gaps that O-Buoys overcome. Advances in floatation, communications, power management, and sensor hardware have been made to overcome the challenges of diminished Arctic sea ice. O-Buoy data provide insights into enhanced seasonal, interannual and spatial variability in atmospheric composition, atmospheric boundary layer control on the amount of halogen activation, enhancement of the atmospheric CO2 signal over the more variable and porous pack ice, and to develop an integrated picture of the coupled ocean/ice/atmosphere system. As part of the Arctic Observing Network, we provide data to the community (www.aoncadis.org).
JAMSTEC Compact Arctic Drifter (J-CAD): A new Generation drifting buoy to observe the Arctic Ocean
NASA Astrophysics Data System (ADS)
Hatakeyama, Kiyoshi; Hosono, Masuo; Shimada, Koji; Kikuchi, Takashi; Nishino, Shigeto
The Arctic Ocean is one of the most sensitive regions to the earth environment changes. Japan Marine Science and Technology Center developed a new drift buoy to observe the Arctic Ocean. The name of the buoy is J-CAD (JAMSTEC Compact Arctic Drifter). From 1991 to 1993, JAMSTEC developed Ice-Ocean Environmental Buoy (IOEB) as a buoy to observe the Arctic Ocean in cooperation with Woods Hole Oceanographic Institution. The J-CAD is the buoy, which adopted the latest technology based on the knowledge and experience of IOEB development. The J-CAD was designed and developed by JAMSTEC and made by a Canadian Company MetOcean. JAMSTEC did design and development, and a Canadian company Met-Ocean made the J-CAD. It acquires meteorological and oceanographic data of the Arctic Ocean, and transmits the data that it measured via satellite. It dose also store the data inside its memory. An Inductive Modem system, which was developed by Sea-Bird Electronics, Inc. in the United States, was adopted in the underwater transmission system that data on each ocean sensor were collected. An ORBCOMM communication system was adopted for the satellite data transmission. J-CAD-1 was installed at 89°41'N 130°20'W on April 24, 2000, and the observation was started. August 1st was the day when 100 days have passed since the J-CAD-1 was installed on the North Pole. And now, the distance J-CAD-1 has covered exceeds 400 km, and it has transmitted data more than 500 k byte. A part of the data is introduced to the public in the homepage (http://w3.jamstec.go.jp: 8338) of the Arctic research group of JAMSTEC.
NASA Astrophysics Data System (ADS)
Davoodi, F.; Shahabi, C.; Burdick, J.; Rais-Zadeh, M.; Menemenlis, D.
2014-12-01
The work had been funded by NASA HQ's office of Cryospheric Sciences Program. Recent observations of the Arctic have shown that sea ice has diminished drastically, consequently impacting the environment in the Arctic and beyond. Certain factors such as atmospheric anomalies, wind forces, temperature increase, and change in the distribution of cold and warm waters contribute to the sea ice reduction. However current measurement capabilities lack the accuracy, temporal sampling, and spatial coverage required to effectively quantify each contributing factor and to identify other missing factors. Addressing the need for new measurement capabilities for the new Arctic regime, we propose a game-changing in-situ Arctic-wide Distributed Mobile Monitoring system called Moball-buoy Network. Moball-buoy Network consists of a number of wind-propelled self-powered inflatable spheres referred to as Moball-buoys. The Moball-buoys are self-powered. They use their novel mechanical control and energy harvesting system to use the abundance of wind in the Arctic for their controlled mobility and energy harvesting. They are equipped with an array of low-power low-mass sensors and micro devices able to measure a wide range of environmental factors such as the ice conditions, chemical species wind vector patterns, cloud coverage, air temperature and pressure, electromagnetic fields, surface and subsurface water conditions, short- and long-wave radiations, bathymetry, and anthropogenic factors such as pollutions. The stop-and-go motion capability, using their novel mechanics, and the heads up cooperation control strategy at the core of the proposed distributed system enable the sensor network to be reconfigured dynamically according to the priority of the parameters to be monitored. The large number of Moball-buoys with their ground-based, sea-based, satellite and peer-to-peer communication capabilities would constitute a wireless mesh network that provides an interface for a global control system. This control system will ensure arctic-wide coverage, will optimize Moball-buoys monitoring efforts according to their available resources and the priority of local areas of high scientific value within the Arctic region. Moball-buoy Network is expected to be the first robust and persistent Arctic-wide environment monitoring system capable of providing reliable readings in near real time
NASA Astrophysics Data System (ADS)
Matrai, P. A.; Williams, C. R.; Rauschenberg, C. D.
2012-12-01
Autonomous, sea ice-tethered buoys ("O-Buoys") are being deployed across the Arctic sea ice for long-term atmospheric measurements, with several O-Buoys having been deployed within the Hudson Bay, Beaufort Sea, and the North Pole. These buoys provide in-situ measurements of ozone, CO_{2} and BrO, as well as meteorological parameters, over the frozen ocean. O-Buoys were designed to transmit daily data over a period of 2 years while deployed in sea ice, as part of automated ice-drifting stations. Due to the logistical challenges of measurements over the Arctic Ocean region, most long term,in-situ observations of atmospheric chemistry have been made at coastal sites or islands near the coast, leaving large spatial and temporal gaps that O-Buoys can overcome. The significant uncertainty that remains in our understanding of the temporal and spatial variability in these parameters as well as the magnitude and/or frequency of long (CO_{2}) and short (ozone depletion) patterns can be overcome. Advances in floatation, communications, power management, and sensor hardware have been made to the original design to overcome the challenges of diminished Arctic sea ice which have resulted in our longest deployments into the summer so far.
Arctic sea-ice diffusion from observed and simulated Lagrangian trajectories
NASA Astrophysics Data System (ADS)
Rampal, Pierre; Bouillon, Sylvain; Bergh, Jon; Ólason, Einar
2016-07-01
We characterize sea-ice drift by applying a Lagrangian diffusion analysis to buoy trajectories from the International Arctic Buoy Programme (IABP) dataset and from two different models: the standalone Lagrangian sea-ice model neXtSIM and the Eulerian coupled ice-ocean model used for the TOPAZ reanalysis. By applying the diffusion analysis to the IABP buoy trajectories over the period 1979-2011, we confirm that sea-ice diffusion follows two distinct regimes (ballistic and Brownian) and we provide accurate values for the diffusivity and integral timescale that could be used in Eulerian or Lagrangian passive tracers models to simulate the transport and diffusion of particles moving with the ice. We discuss how these values are linked to the evolution of the fluctuating displacements variance and how this information could be used to define the size of the search area around the position predicted by the mean drift. By comparing observed and simulated sea-ice trajectories for three consecutive winter seasons (2007-2011), we show how the characteristics of the simulated motion may differ from or agree well with observations. This comparison illustrates the usefulness of first applying a diffusion analysis to evaluate the output of modeling systems that include a sea-ice model before using these in, e.g., oil spill trajectory models or, more generally, to simulate the transport of passive tracers in sea ice.
Scaling properties of the Arctic sea ice Deformation from Buoy Dispersion Analysis
NASA Astrophysics Data System (ADS)
Weiss, J.; Rampal, P.; Marsan, D.; Lindsay, R.; Stern, H.
2007-12-01
A temporal and spatial scaling analysis of Arctic sea ice deformation is performed over time scales from 3 hours to 3 months and over spatial scales from 300 m to 300 km. The deformation is derived from the dispersion of pairs of drifting buoys, using the IABP (International Arctic Buoy Program) buoy data sets. This study characterizes the deformation of a very large solid plate -the Arctic sea ice cover- stressed by heterogeneous forcing terms like winds and ocean currents. It shows that the sea ice deformation rate depends on the scales of observation following specific space and time scaling laws. These scaling properties share similarities with those observed for turbulent fluids, especially for the ocean and the atmosphere. However, in our case, the time scaling exponent depends on the spatial scale, and the spatial exponent on the temporal scale, which implies a time/space coupling. An analysis of the exponent values shows that Arctic sea ice deformation is very heterogeneous and intermittent whatever the scales, i.e. it cannot be considered as viscous-like, even at very large time and/or spatial scales. Instead, it suggests a deformation accommodated by a multi-scale fracturing/faulting processes.
2014-09-30
dropsondes, micro- aircraft), cloud top/base heights Arctic Ocean Surface Temperature project Steele Buoy drops for SLP , SST, SSS, & surface velocity...Colón & Vancas (NIC) Drop buoys for SLP , temperature and surface velocity Waves & Fetch in the MIZ Thompson SWIFTS buoys measuring wave energy...Expendable CTD, AXCP= Air Expendable Current Profiler, SLP = Sea Level atmospheric Pressure, SST= Seas Surface Temperature, A/C= aircraft, FSD= Floe Size Distribution, SIC=Sea Ice Concentration
Mass Balance of Multiyear Sea Ice in the Southern Beaufort Sea
2013-09-30
model of MY ice circulation, which is shown in Figure 1. In this model , we consider the Beaufort Sea to consist of four zones defined by mean drift...Arctic Regional Climate Model Simulation Project 3 International Arctic Buoy Program 4 Sea ice Experiment - Dynamic Nature of the Arctic 5Cold...2 Table 2: Datasets compiled to date Geophysical data type Source Time period acquired Buoy tracks IABP 12 hrly position data 1978-2012 Ice
NASA Astrophysics Data System (ADS)
Hebert, David A.; Allard, Richard A.; Metzger, E. Joseph; Posey, Pamela G.; Preller, Ruth H.; Wallcraft, Alan J.; Phelps, Michael W.; Smedstad, Ole Martin
2015-12-01
In this study the forecast skill of the U.S. Navy operational Arctic sea ice forecast system, the Arctic Cap Nowcast/Forecast System (ACNFS), is presented for the period February 2014 to June 2015. ACNFS is designed to provide short term, 1-7 day forecasts of Arctic sea ice and ocean conditions. Many quantities are forecast by ACNFS; the most commonly used include ice concentration, ice thickness, ice velocity, sea surface temperature, sea surface salinity, and sea surface velocities. Ice concentration forecast skill is compared to a persistent ice state and historical sea ice climatology. Skill scores are focused on areas where ice concentration changes by ±5% or more, and are therefore limited to primarily the marginal ice zone. We demonstrate that ACNFS forecasts are skilful compared to assuming a persistent ice state, especially beyond 24 h. ACNFS is also shown to be particularly skilful compared to a climatologic state for forecasts up to 102 h. Modeled ice drift velocity is compared to observed buoy data from the International Arctic Buoy Programme. A seasonal bias is shown where ACNFS is slower than IABP velocity in the summer months and faster in the winter months. In February 2015, ACNFS began to assimilate a blended ice concentration derived from Advanced Microwave Scanning Radiometer 2 (AMSR2) and the Interactive Multisensor Snow and Ice Mapping System (IMS). Preliminary results show that assimilating AMSR2 blended with IMS improves the short-term forecast skill and ice edge location compared to the independently derived National Ice Center Ice Edge product.
Scaling properties of sea ice deformation from buoy dispersion analysis
NASA Astrophysics Data System (ADS)
Rampal, P.; Weiss, J.; Marsan, D.; Lindsay, R.; Stern, H.
2008-03-01
A temporal and spatial scaling analysis of Arctic sea ice deformation is performed over timescales from 3 h to 3 months and over spatial scales from 300 m to 300 km. The deformation is derived from the dispersion of pairs of drifting buoys, using the IABP (International Arctic Buoy Program) buoy data sets. This study characterizes the deformation of a very large solid plate (the Arctic sea ice cover) stressed by heterogeneous forcing terms like winds and ocean currents. It shows that the sea ice deformation rate depends on the scales of observation following specific space and time scaling laws. These scaling properties share similarities with those observed for turbulent fluids, especially for the ocean and the atmosphere. However, in our case, the time scaling exponent depends on the spatial scale, and the spatial exponent on the temporal scale, which implies a time/space coupling. An analysis of the exponent values shows that Arctic sea ice deformation is very heterogeneous and intermittent whatever the scales, i.e., it cannot be considered as viscous-like, even at very large time and/or spatial scales. Instead, it suggests a deformation accommodated by a multiscale fracturing/faulting processes.
NASA Astrophysics Data System (ADS)
Flocco, D.; Laxon, S. W.; Feltham, D. L.; Haas, C.
2011-12-01
The GlobIce project has provided high resolution sea ice product datasets over the Arctic derived from SAR data in the ESA archive. The products are validated sea ice motion, deformation and fluxes through straits. GlobIce sea ice velocities, deformation data and sea ice concentration have been validated using buoy data provided by the International Arctic Buoy Program (IABP). Over 95% of the GlobIce and buoy data analysed fell within 5 km of each other. The GlobIce Eulerian image pair product showed a high correlation with buoy data. The sea ice concentration product was compared to SSM/I data. An evaluation of the validity of the GlobICE data will be presented in this work. GlobICE sea ice velocity and deformation were compared with runs of the CICE sea ice model: in particular the mass fluxes through the straits were used to investigate the correlation between the winter behaviour of sea ice and the sea ice state in the following summer.
Snow depth evolution on sea ice from Snow Buoy measurement
NASA Astrophysics Data System (ADS)
Nicolaus, M.; Arndt, S.; Hendricks, S.; Hoppmann, M.; Katlein, C.; König-Langlo, G.; Nicolaus, A.; Rossmann, H. L.; Schiller, M.; Schwegmann, S.; Langevin, D.
2016-12-01
Snow cover is an Essential Climate Variable. On sea ice, snow dominates the energy and momentum exchanges across the atmosphere-ice-ocean interfaces, and actively contributes to sea ice mass balance. Yet, snow depth on sea ice is one of the least known and most difficult to observe parameters of the Arctic and Antarctic; mainly due to its exceptionally high spatial and temporal variability. In this study; we present a unique time series dataset of snow depth and air temperature evolution on Arctic and Antarctic sea ice recorded by autonomous instruments. Snow Buoys record snow depth with four independent ultrasonic sensors, increasing the reliability of the measurements and allowing for additional analyses. Auxiliary measurements include surface and air temperature, barometric pressure and GPS position. 39 deployments of such Snow Buoys were achieved over the last three years either on drifting pack ice, on landfast sea ice or on an ice shelf. Here we highlight results from two pairs of Snow Buoys installed on drifting pack ice in the Weddell Sea. The data reveals large regional differences in the annual cycle of snow depth. Almost no reduction in snow depth (snow melt) was observed in the inner and southern part of the Weddell Sea, allowing a net snow accumulation of 0.2 to 0.9 m per year. In contrast, summer snow melt close to the ice edge resulted in a decrease of about 0.5 m during the summer 2015/16. Another array of eight Snow Buoys was installed on central Arctic sea ice in September 2015. Their air temperature record revealed exceptionally high air temperatures in the subsequent winter, even exceeding the melting point but with almost no impact on snow depth at that time. Future applications of Snow Buoys on Arctic and Antarctic sea ice will allow additional inter-annual studies of snow depth and snow processes, e.g. to support the development of snow depth data products from airborne and satellite data or though assimilation in numerical models.
NASA Astrophysics Data System (ADS)
Flocco, D.; Laxon, S. W.; Feltham, D. L.; Haas, C.
2012-04-01
The GlobIce project has provided high resolution sea ice product datasets over the Arctic derived from SAR data in the ESA archive. The products are validated sea ice motion, deformation and fluxes through straits. GlobIce sea ice velocities, deformation data and sea ice concentration have been validated using buoy data provided by the International Arctic Buoy Program (IABP). Over 95% of the GlobIce and buoy data analysed fell within 5 km of each other. The GlobIce Eulerian image pair product showed a high correlation with buoy data. The sea ice concentration product was compared to SSM/I data. An evaluation of the validity of the GlobICE data will be presented in this work. GlobICE sea ice velocity and deformation were compared with runs of the CICE sea ice model: in particular the mass fluxes through the straits were used to investigate the correlation between the winter behaviour of sea ice and the sea ice state in the following summer.
Remote Sensing of the Arctic Seas.
ERIC Educational Resources Information Center
Weeks, W. F.; And Others
1986-01-01
Examines remote sensing of the arctic seas by discussing: (1) passive microwave sensors; (2) active microwave sensors; (3) other types of sensors; (4) the future deployment of sensors; (5) data buoys; and (6) future endeavors. (JN)
NASA Astrophysics Data System (ADS)
Richter-Menge, J.; Stott, G.; Harriman, C.; Perovich, D. K.; Elder, B. C.; Polashenski, C.
2013-12-01
Over the past 4 school years, our team of Arctic sea ice researchers and middle school teachers has collaborated in an educational outreach activity to develop a series of earth science classes aimed at 8th grade science students. Central to the effort is an environmental observation site installed at the school, designed to closely mimic sea ice mass balance buoys deployed as part of an NSF-sponsored Arctic Observing Network (AON) project. The site located at the school collects data on air temperature, barometric pressure, snow depth, and snow and ground temperatures. Working directly with the research team over the course of the school year, students learn to collect, process, and analyze the local environmental data. Key to the experience is the students' opportunity to pose and address open-ended questions about a set of scientific data that is inherently familiar to them, since it reflects the seasonal conditions they are witnessing (e.g. the 2011-12 New England winter with no snow). During the series of classes, students are also exposed to the similar set of environmental data collected in the Arctic, via a sea ice mass balance buoy they ';adopt.' The arctic data set opens the door to discussions about climate change and its particularly dramatic affect on the arctic environment. Efforts are underway to transform this outreach project into an expanded earth science classroom module for use at other schools. Portability will require an approach that makes connections to the Arctic without a reliance on the multiple visits to the classroom by the research team (e.g. forming and facilitating partnerships with Arctic schools and field researchers via the internet). We are also evaluating the possibility of constructing low cost, portable weather stations to be used with the module.
Sea ice motions in the Central Arctic pack ice as inferred from AVHRR imagery
NASA Technical Reports Server (NTRS)
Emery, William; Maslanik, James; Fowler, Charles
1995-01-01
Synoptic observations of ice motion in the Arctic Basin are currently limited to those acquired by drifting buoys and, more recently, radar data from ERS-1. Buoys are not uniformly distributed throughout the Arctic, and SAR coverage is currently limited regionally and temporally due to the data volume, swath width, processing requirements, and power needs of the SAR. Additional ice-motion observations that can map ice responses simultaneously over large portions of the Arctic on daily to weekly time intervals are thus needed to augment the SAR and buoys data and to provide an intermediate-scale measure of ice drift suitable for climatological analyses and ice modeling. Principal objectives of this project were to: (1) demonstrate whether sufficient ice features and ice motion existed within the consolidated ice pack to permit motion tracking using AVHRR imagery; (2) determine the limits imposed on AVHRR mapping by cloud cover; and (3) test the applicability of AVHRR-derived motions in studies of ice-atmosphere interactions. Each of these main objectives was addressed. We conclude that AVHRR data, particularly when blended with other available observations, provide a valuable data set for studying sea ice processes. In a follow-on project, we are now extending this work to cover larger areas and to address science questions in more detail.
Calibration of Sea Ice Motion from QuikSCAT with those from SSM/I and Buoy
NASA Technical Reports Server (NTRS)
Liu, Antony K.; Zhao, Yun-He; Zukor, Dorothy J. (Technical Monitor)
2001-01-01
QuikSCAT backscatter and DMSP SSM/I radiance data are used to derive sea ice motion for both the Arctic and Antarctic region using wavelet analysis method. This technique provides improved spatial coverage over the existing array of Arctic Ocean buoys and better temporal resolution over techniques utilizing satellite data from Synthetic Aperture Radar (SAR). Sea ice motion of the Arctic for the period from October 1999 to March 2000 derived from QuikSCAT and SSM/I data agrees well with that derived from ocean buoys quantitatively. Thus the ice tracking results from QuikSCAT and SSM/I are complement to each other, Then, three sea-ice drift daily results from QuikSCAT, SSM/I, and buoy data can be merged to generate composite maps with more complete coverage of sea ice motion than those from single data source. A series of composite sea ice motion maps for December 1999 show that the major circulation patterns of sea ice motion are changing and shifting significantly within every four days and they are dominated by wind forcing. Sea-ice drift in the summer can not be derived from NSCAT and SSM/I data. In later summer of 1999 (in September), however, QuikSCAT data can provide good sea ice motion information in the Arctic. QuiksCAT can also provide at least partial sea ice motion information until June 15 in early summer 1999. For the Antarctic, case study shows that sea ice motion derived from QuikSCAT data is predominantly forced by and is consistent with wind field derived from QuikSCAT around the polar region. These calibrated/validated results indicate that QuikSCAT, SSM/I, and buoy merged daily ice motion are suitably accurate to identify and closely locate sea ice processes, and to improve our current knowledge of sea ice drift and related processes through the data assimilation of ocean-ice numerical model.
NASA Astrophysics Data System (ADS)
Hill, V. J.; Steele, M.; Light, B.
2016-02-01
As part of the Arctic Observing Network, a new ice-tethered buoy has been developed for monitoring the role of sunlight in regulating ocean temperature, phytoplankton growth, and carbon cycling. A 20 or 50 m string (depending on local bathymetry) supports sensors both within and below the ice for the hourly measurement of downwelling irradiance, temperature, Chlorophyll a, light backscattering, and dissolved organic material (DOM). Two buoys were deployed in March 2014 and two in March 2015. Because the buoys are engineered to survive melting out of first year ice, they have successfully provided complete seasonal records of water column warming, phytoplankton abundance and photo-oxidation patterns in the Pacific Arctic Region. The data collected will be used to determine whether reduced ice extent and thinner ice are driving increases in under ice warming, accelerating bottom ice ablation, increasing available photosynthetic radiation to support large under ice blooms, and to quantify photo-oxidation of the DOM pool. Observations so far have revealed strong under ice daily warming as high as ±0.5 °C driven by local solar radiation. Water column absorption was dominated by colored dissolved organic material which served to trap solar radiation in the upper water column. Chlorophyll concentrations observed in June and July indicated high phytoplankton abundance beneath the ice. Light intensity at this time was not sufficient to support growth rates high enough to produce the 8 to 10 mg m-3 of chlorophyll observed. We hypothesize that phytoplankton were advected under the ice from the ice edge. However, once there phytoplankton were able to sustain low growth rates leading to nutrient limitation before open water status was reached. Strong daily cycles of photo-oxidation have also been observed in the late summer that indicate the fast cycling of highly labile DOM in the open waters of the Pacific Arctic Region.
NASA Astrophysics Data System (ADS)
Halfacre, John W.
The photochemically-induced destruction of ground-level Arctic ozone in the Arctic occurs at the onset of spring, in concert with polar sunrise. Solar radiation is believed to stimulate a series of reactions that cause the production and release of molecular halogens from frozen, salty surfaces, though this mechanism is not yet well understood. The subsequent photolysis of molecular halogens produces reactive halogen atoms that remove ozone from the atmosphere in these so-called "Ozone Depletion Events" (ODEs). Given that much of the Arctic region is sunlit, meteorologically stable, and covered by saline ice and snow, it is expected that ODEs could be a phenomenon that occurs across the entire Arctic region. Indeed, an ever-growing body of evidence from coastal sites indicates that Arctic air masses devoid of O3 most often pass over sea ice-covered regions before arriving at an observation site, suggesting ODE chemistry occurs upwind over the frozen Arctic Ocean. However, outside of coastal observations, there exist very few long-term observations from the Arctic Ocean from which quantitative assessments of basic ODE characteristics can be made. This work presents the interpretation of ODEs through unique chemical and meteorological observations from several ice-tethered buoys deployed around the Arctic Ocean. These observations include detection of ozone, bromine monoxide, and measurements of temperature, relative humidity, atmospheric pressure, wind speed, and wind direction. To assess whether the O-Buoys were observing locally based depletion chemistry or the transport of ozone-poor air masses, periods of ozone decay were interpreted based on current understanding of ozone depletion kinetics, which are believed to follow a pseudo-first order rate law. In addition, the spatial extents of ODEs were estimated using air mass trajectory modeling to assess whether they are a localized or synoptic phenomenon. Results indicate that current understanding of the responsible chemical mechanisms are lacking, ODEs are observed primarily due to air mass transport (even in the Arctic Ocean), or some combination of both. Air mass trajectory modeling was also used in tandem with remote sensing observations of sea ice to determine the types of surfaces air masses were exposed to before arriving at O-Buoys. The impact of surface exposure was subsequently compared with local meteorology to assess which variables had the most effect on O 3 variability. For two observation sites, the impact of local meteorology was significantly stronger than air mass history, while a third was inconclusive. Finally, this work tests the viability of the hypothesis that initial production of molecular halogens from frozen saline surfaces results from photolytic production of the hydroxyl radical, and could be enhanced in the presence of O3. This investigation was enabled by a custom frozen-walled flow reactor coupled with chemical ionization spectrometry. It was found that hydroxyl radical could indeed promote the production and release of iodine, bromine, and chlorine, and that this production could be enhanced in the presence of ozone.
Arctic Sea Ice Basal Melt Onset Variability and Associated Ocean Surface Heating
NASA Astrophysics Data System (ADS)
Merrick, R. A.; Hutchings, J. K.
2015-12-01
The interannual and regional variability in Arctic sea ice melt has previously been characterized only in terms of surface melting. A focus on the variability in the onset of basal melt is additionally required to understand Arctic melt patterns. Monitoring basal melt provides a glimpse into the importance of ocean heating to sea ice melt. This warming is predominantly through seawater exposure due to lead opening and the associated solar warming at the ocean's surface. We present the temporal variability in basal melt onset observed by ice mass balance buoys throughout the Arctic Ocean since 2003, providing a different perspective than the satellite microwave data used to measure the onset of surface melt. We found that melt onset varies greatly, even for buoys deployed within 100km of each other. Therefore large volumes of data are necessary to accurately estimate the variability of basal melt onset. Once the variability of basal melt onset has been identified, we can investigate how this range has been changing as a response to atmospheric and oceanic warming, changes in ice morphology as well as the intensification of the ice albedo feedback.
Time Lapse Photography From Arctic Buoys
NASA Astrophysics Data System (ADS)
Valentic, T. A.; Matrai, P.; Woods, J. E.
2013-12-01
We have equipped a number of buoys with cameras that have been deployed throughout the Arctic. These systems need to be simple, reliable and low power. The images are transmitted over an Iridium satellite link and assembled into long running movies. We have captured a number of interesting events, observed the ice dynamics through the year and visits by local wildlife. Each of the systems have been deployed for periods of up to a year, with images every hour. The cameras have proved to be a great outreach tool and are routinely watched by number of people on our websites. This talk will present the techniques used in developing these camera systems, the methods used for reliably transmitting the images and the process for generating the movies.
UpTempO Buoys for Understanding and Predictions
2016-02-28
fall cooling, and interannually as sea ice retreats and the warming season lengthens. The effort was a contribution to the multi-investigator ONR...relationships between sea ice retreat and upper ocean warming. ACCOMPLISHED I. Buoy deployments and data: We worked with the Pacific Gyre (PG...have for the first time investigated the daily variation in ice edge retreat speed from a pan-arctic perspective. We have found that the pace of ice
Air Deployable Underwater Glider and Buoy Development for Arctic and Oceanographic Sensing
NASA Astrophysics Data System (ADS)
Legnos, P. J.
2013-12-01
LBI developed under a NOAA SBIR the AXIB (Airborne eXpendable Ice Buoy). The initial buoy was developed to collect barometric pressure, air temperature two meters above the surface and sea surface or ice temperature. A number of these AXIBs have been successfully deployed in the Arctic and Antarctic. Currently we are in the process of integrating additional sensors to include an anemometer, thermistor chain and hydrophones. Further development is in process for the integration of solar and wind recharging systems and lower power sensors and processing LBI developed under an ONR SBIR Grant two Air Deployable Underwater Gliders. They are primarily designed for air deployment from Navy P-3 or P-8 Aircraft though easily deployed from other aircraft or helicopters. The A-size (4 7/8'dia. X 36' long) and the 12 ¾ (12 ¾' dia. X 9' 9' long). On the development side we are in the process of integrating sensors and enhancing the battery storage capacity. We anticipate a broad range of Oceanographic sensing missions for these Gliders.
NASA Astrophysics Data System (ADS)
Calder, J.; Overland, J.; Uttal, T.; Richter-Menge, J.; Rigor, I.; Crane, K.
2004-12-01
NOAA has initiated four activities that respond to the Arctic Climate Impact Assessment(ACIA) recommendations and represent contributions toward the IPY: 1) Arctic cloud, radiation and aerosol observatories, 2) documentation and attribution of changes in sea-ice thickness through direct measurement and modeling, 3) deriving added value from existing multivariate and historical data, and 4) following physical and biological changes in the northern Bering and Chukchi Seas. Northeast Canada, the central Arctic coast of Russia and the continuing site at Barrow have been chosen as desirable radiation/cloud locations as they exhibit different responses to Arctic Oscillation variability. NOAA is closely collaborating with Canadian groups to establish an observatory at Eureka. NOAA has begun deployment of a network of ice-tethered ice mass balance buoys complemented by several ice profiling sonars. In combination with other sea ice investigators, the Arctic buoy program, and satellites, changes can be monitored more effectively in sea ice throughout the Arctic. Retrospective data analyses includes analysis of Arctic clouds and radiation from surface and satellite measurements, correction of systematic errors in TOVS radiance data sets for the Arctic which began in 1979, addressing the feasibility of an Arctic System Reanalysis, and an Arctic Change Detection project that incorporates historical and recent physical and biological observations and news items at a website, www.arctic.noaa.gov. NOAA has begun a long-term effort to detect change in ecosystem indicators in the northern Bering and Chukchi Seas that could provide a model for other northern marine ecosystems. The first efforts were undertaken in summer 2004 during a joint Russian-US cruise that mapped the regions physical, chemical and biological parameters to set the stage for future operations over the longer term. A line of biophysical moorings provide detection of the expected warming of this area. A retrospective analysis is also underway. NOAA is open to partnerships as the IPY develops.
Storm-driven Mixing and Potential Impact on the Arctic Ocean
NASA Technical Reports Server (NTRS)
Yang, Jiayan; Comiso, Josefino; Walsh, David; Krishfield, Richard; Honjo, Susumu; Koblinsky, Chester J. (Technical Monitor)
2001-01-01
Observations of the ocean, atmosphere, and ice made by Ice-Ocean Environmental Buoys (IOEBs) indicate that mixing events reaching the depth of the halocline have occurred in various regions in the Arctic Ocean. Our analysis suggests that these mixing events were mechanically forced by intense storms moving across the buoy sites. In this study, we analyzed these mixing events in the context of storm developments that occurred in the Beaufort Sea and in the general area just north of Fram Strait, two areas with quite different hydrographic structures. The Beaufort Sea is strongly influenced by inflow of Pacific water through Bering Strait, while the area north of Fram Strait is directly affected by the inflow of warm and salty North Atlantic water. Our analyses of the basin-wide evolution of the surface pressure and geostrophic wind fields indicate that the characteristics of the storms could be very different. The buoy-observed mixing occurred only in the spring and winter seasons when the stratification was relatively weak. This indicates the importance of stratification, although the mixing itself was mechanically driven. We also analyze the distribution of storms, both the long-term climatology as well as the patterns for each year in the last two decades. The frequency of storms is also shown to be correlated- (but not strongly) to Arctic Oscillation indices. This study indicates that the formation of new ice that leads to brine rejection is unlikely the mechanism that results in the type of mixing that could overturn the halocline. On the other hand, synoptic-scale storms can force mixing deep enough to the halocline and thermocline layer. Despite a very stable stratification associated with the Arctic halocline, the warm subsurface thermocline water is not always insulated from the mixed layer.
Increasing frequency and duration of Arctic winter warming events
NASA Astrophysics Data System (ADS)
Graham, R. M.; Cohen, L.; Petty, A.; Boisvert, L.; Rinke, A.; Hudson, S. R.; Nicolaus, M.; Granskog, M. A.
2017-12-01
Record low Arctic sea ice extents were observed during the last three winter seasons (March). During each of these winters, near-surface air temperatures close to 0°C were observed, in situ, over sea ice in the central Arctic. Recent media reports and scientific studies suggest that such winter warming events were unprecedented for the Arctic. Here we use in situ winter (December-March) temperature observations, such as those from Soviet North Pole drifting stations and ocean buoys, to determine how common Arctic winter warming events are. The earliest record we find of a winter warming event was in March 1896, where a temperature of -3.7˚C was observed at 84˚N during the Fram expedition. Observations of winter warming events exist over most of the Arctic Basin. Despite a limited observational network, temperatures exceeding -5°C were measured in situ during more than 30% of winters from 1954 to 2010, by either North Pole drifting stations or ocean buoys. Correlation coefficients between the atmospheric reanalysis, ERA-Interim, and these in-situ temperature records are shown to be on the order of 0.90. This suggests that ERA-Interim is a suitable tool for studying Arctic winter warming events. Using the ERA-Interim record (1979-2016), we show that the North Pole (NP) region typically experiences 10 warming events (T2m > -10°C) per winter, compared with only five in the Pacific Central Arctic (PCA). We find a positive trend in the overall duration of winter warming events for both the NP region (4.25 days/decade) and PCA (1.16 days/decade), due to an increased number of events of longer duration.
Observed Changes at the Surface of the Arctic Ocean
NASA Astrophysics Data System (ADS)
Ortmeyer, M.; Rigor, I.
2004-12-01
The Arctic has long been considered a harbinger of global climate change since simulations with global climate models predict that if the concentration of CO2 in the atmosphere doubles, the Arctic would warm by more than 5°C, compared to a warming of 2°C for subpolar regions (Manabe et al., 1991). And indeed, studies of the observational records show polar amplification of the warming trends (e.g. Serreze and Francis, 2004). These temperature trends are accompanied by myriad concurrent changes in Arctic climate. One of the first indicators of Arctic climate change was found by Walsh et al. (1996) using sea level pressure (SLP) data from the International Arctic Buoy Programme (IABP, http://iabp.apl.washington.edu). In this study, they showed that SLP over the Arctic Ocean decreased by over 4 hPa from 1979 - 1994. The decreases in SLP (winds) over the Arctic Ocean, forced changes in the circulation of sea ice and the surface ocean currents such that the Beaufort Gyre is reduced in size and speed (e.g. Rigor et al., 2002). Data from the IABP has also been assimilated into the global surface air temperature (SAT) climatologies (e.g. Jones et al. 1999), and the IABP SAT analysis shows that the temperature trends noted over land extend out over the Arctic Ocean. Specifically, Rigor et al. (2000) found warming trends in SAT over the Arctic Ocean during win¬ter and spring, with values as high as 2°C/decade in the eastern Arctic during spring. It should be noted that many of the changes in Arctic climate were first observed or explained using data from the IABP. The observations from IABP have been one of the cornerstones for environmental forecasting and studies of climate and climate change. These changes have a profound impact on wildlife and people. Many species and cultures depend on the sea ice for habitat and subsistence. Thus, monitoring the Arctic Ocean is crucial not only for our ability to detect climate change, but also to improve our understanding of the Arctic and global climate system, and for forecasting weather and sea ice conditions. The IABP provides the longest continuing record of observations for the Arctic Ocean.
ARCTIC SEA ICE EXTENT AND DRIFT, MODELED AS A VISCOUS FLUID.
Ling, Chi-Hai; Parkinson, Claire L.
1986-01-01
A dynamic/thermodynamic numerical model of sea ice has been used to calculate the yearly cycle of sea ice thicknesses, concentrations, and velocities in the Arctic Ocean and surrounding seas. The model combines the formulations of two previous models, taking the thermodynamics and momentum equations from the model of Parkinson and Washington and adding the constitutive equation and equation of state from the model of Ling, Rasmussen, and Campbell. Simulated annually averaged ice drift vectors compare well with observed ice drift from the Arctic Ocean Buoy Program.
Arctic Sea Ice Thickness - Past, Present And Future
NASA Astrophysics Data System (ADS)
Wadhams, P.
2007-12-01
In November 2005 the International Workshop on Arctic Sea Ice Thickness: Past, Present and Future was held at Rungstedgaard Conference Center, near Copenhagen, Denmark. The proceedings of the Workshop were subsequently published as a book by the European Commission. In this review we summarise the conclusions of the Workshop on the techniques which show the greatest promise for thickness monitoring on different spatial and temporal scales, and for different purposes. Sonic methods, EM techniques, buoys and satellite methods will be considered. Some copies of the book will be available at the lecture, and others can be ordered from the European Commission. The paper goes on to consider early results from some of the latest measurements on Arctic sea ice thickness done in 2007. These comprise a trans-Arctic voyage by a UK submarine, HMS "Tireless", equipped with a Kongsberg 3002 multibeam sonar which generates a 3-D digital terrain map of the ice underside; and experiments at the APLIS ice station in the Beaufort Sea carried out by the Gavia AUV equipped with a GeoSwath interferometric sonar. In both cases 3-D mapping of sea ice constitutes a new step forward in sea ice data collection, but in the case of the submarine the purpose is to map change in ice thickness (comparing results with a 2004 "Tireless" cruise and with US and UK data prior to 2000), while for the small AUV the purpose is intensive local mapping of a few ridges to improve our knowledge of their structure, as part of a multisensor programme
Autonomous Ice Mass Balance Buoys for Seasonal Sea Ice
NASA Astrophysics Data System (ADS)
Whitlock, J. D.; Planck, C.; Perovich, D. K.; Parno, J. T.; Elder, B. C.; Richter-Menge, J.; Polashenski, C. M.
2017-12-01
The ice mass-balance represents the integration of all surface and ocean heat fluxes and attributing the impact of these forcing fluxes on the ice cover can be accomplished by increasing temporal and spatial measurements. Mass balance information can be used to understand the ongoing changes in the Arctic sea ice cover and to improve predictions of future ice conditions. Thinner seasonal ice in the Arctic necessitates the deployment of Autonomous Ice Mass Balance buoys (IMB's) capable of long-term, in situ data collection in both ice and open ocean. Seasonal IMB's (SIMB's) are free floating IMB's that allow data collection in thick ice, thin ice, during times of transition, and even open water. The newest generation of SIMB aims to increase the number of reliable IMB's in the Arctic by leveraging inexpensive commercial-grade instrumentation when combined with specially developed monitoring hardware. Monitoring tasks are handled by a custom, expandable data logger that provides low-cost flexibility for integrating a large range of instrumentation. The SIMB features ultrasonic sensors for direct measurement of both snow depth and ice thickness and a digital temperature chain (DTC) for temperature measurements every 2cm through both snow and ice. Air temperature and pressure, along with GPS data complete the Arctic picture. Additionally, the new SIMB is more compact to maximize deployment opportunities from multiple types of platforms.
Aircraft Surveys of the Beaufort Sea Seasonal Ice Zone
NASA Astrophysics Data System (ADS)
Morison, J.
2016-02-01
The Seasonal Ice Zone Reconnaissance Surveys (SIZRS) is a program of repeated ocean, ice, and atmospheric measurements across the Beaufort-Chukchi sea seasonal sea ice zone (SIZ) utilizing US Coast Guard Arctic Domain Awareness (ADA) flights of opportunity. The SIZ is the region between maximum winter sea ice extent and minimum summer sea ice extent. As such, it contains the full range of positions of the marginal ice zone (MIZ) where sea ice interacts with open water. The increasing size and changing air-ice-ocean properties of the SIZ are central to recent reductions in Arctic sea ice extent. The changes in the interplay among the atmosphere, ice, and ocean require a systematic SIZ observational effort of coordinated atmosphere, ice, and ocean observations covering up to interannual time-scales, Therefore, every year beginning in late Spring and continuing to early Fall, SIZRS makes monthly flights across the Beaufort Sea SIZ aboard Coast Guard C-130H aircraft from USCG Air Station Kodiak dropping Aircraft eXpendable CTDs (AXCTD) and Aircraft eXpendable Current Profilers (AXCP) for profiles of ocean temperature, salinity and shear, dropsondes for atmospheric temperature, humidity, and velocity profiles, and buoys for atmosphere and upper ocean time series. Enroute measurements include IR imaging, radiometer and lidar measurements of the sea surface and cloud tops. SIZRS also cooperates with the International Arctic Buoy Program for buoy deployments and with the NOAA Earth System Research Laboratory atmospheric chemistry sampling program on board the aircraft. Since 2012, SIZRS has found that even as SIZ extent, ice character, and atmospheric forcing varies year-to-year, the pattern of ocean freshening and radiative warming south of the ice edge is consistent. The experimental approach, observations and extensions to other projects will be discussed.
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.
Inter-comparison of isotropic and anisotropic sea ice rheology in a fully coupled model
NASA Astrophysics Data System (ADS)
Roberts, A.; Cassano, J. J.; Maslowski, W.; Osinski, R.; Seefeldt, M. W.; Hughes, M.; Duvivier, A.; Nijssen, B.; Hamman, J.; Hutchings, J. K.; Hunke, E. C.
2015-12-01
We present the sea ice climate of the Regional Arctic System Model (RASM), using a suite of new physics available in the Los Alamos Sea Ice Model (CICE5). RASM is a high-resolution fully coupled pan-Arctic model that also includes the Parallel Ocean Program (POP), the Weather Research and Forecasting Model (WRF) and Variable Infiltration Capacity (VIC) land model. The model domain extends from ~45˚N to the North Pole and is configured to run at ~9km resolution for the ice and ocean components, coupled to 50km resolution atmosphere and land models. The baseline sea ice model configuration includes mushy-layer sea ice thermodynamics and level-ice melt ponds. Using this configuration, we compare the use of isotropic and anisotropic sea ice mechanics, and evaluate model performance using these two variants against observations including Arctic buoy drift and deformation, satellite-derived drift and deformation, and sea ice volume estimates from ICESat. We find that the isotropic rheology better approximates spatial patterns of thickness observed across the Arctic, but that both rheologies closely approximate scaling laws observed in the pack using buoys and RGPS data. A fundamental component of both ice mechanics variants, the so called Elastic-Viscous-Plastic (EVP) and Anisotropic-Elastic-Plastic (EAP), is that they are highly sensitive to the timestep used for elastic sub-cycling in an inertial-resolving coupled framework, and this has a significant affect on surface fluxes in the fully coupled framework.
Mechanical sea-ice strength parameterized as a function of ice temperature
NASA Astrophysics Data System (ADS)
Hata, Yukie; Tremblay, Bruno
2016-04-01
Mechanical sea-ice strength is key for a better simulation of the timing of landlock ice onset and break-up in the Canadian Arctic Archipelago (CAA). We estimate the mechanical strength of sea ice in the CAA by analyzing the position record measured by the several buoys deployed in the CAA between 2008 and 2013, and wind data from the Canadian Meteorological Centre's Global Deterministic Prediction System (CMC_GDPS) REforecasts (CGRF). First, we calculate the total force acting on the ice using the wind data. Next, we estimate upper (lower) bounds on the sea-ice strength by identifying cases when the sea ice deforms (does not deform) under the action of a given total force. Results from this analysis show that the ice strength of landlock sea ice in the CAA is approximately 40 kN/m on the landfast ice onset (in ice growth season). Additionally, it becomes approximately 10 kN/m on the landfast ice break-up (in melting season). The ice strength decreases with ice temperature increase, which is in accord with results from Johnston [2006]. We also include this new parametrization of sea-ice strength as a function of ice temperature in a coupled slab ocean sea ice model. The results from the model with and without the new parametrization are compared with the buoy data from the International Arctic Buoy Program (IABP).
NASA Astrophysics Data System (ADS)
Meier, Walter Neil
This thesis demonstrates the applicability of data assimilation methods to improve observed and modeled ice motion fields and to demonstrate the effects of assimilated motion on Arctic processes important to the global climate and of practical concern to human activities. Ice motions derived from 85 GHz and 37 GHz SSM/I imagery and estimated from two-dimensional dynamic-thermodynamic sea ice models are compared to buoy observations. Mean error, error standard deviation, and correlation with buoys are computed for the model domain. SSM/I motions generally have a lower bias, but higher error standard deviations and lower correlation with buoys than model motions. There are notable variations in the statistics depending on the region of the Arctic, season, and ice characteristics. Assimilation methods are investigated and blending and optimal interpolation strategies are implemented. Blending assimilation improves error statistics slightly, but the effect of the assimilation is reduced due to noise in the SSM/I motions and is thus not an effective method to improve ice motion estimates. However, optimal interpolation assimilation reduces motion errors by 25--30% over modeled motions and 40--45% over SSM/I motions. Optimal interpolation assimilation is beneficial in all regions, seasons and ice conditions, and is particularly effective in regimes where modeled and SSM/I errors are high. Assimilation alters annual average motion fields. Modeled ice products of ice thickness, ice divergence, Fram Strait ice volume export, transport across the Arctic and interannual basin averages are also influenced by assimilated motions. Assimilation improves estimates of pollutant transport and corrects synoptic-scale errors in the motion fields caused by incorrect forcings or errors in model physics. The portability of the optimal interpolation assimilation method is demonstrated by implementing the strategy in an ice thickness distribution (ITD) model. This research presents an innovative method of combining a new data set of SSM/I-derived ice motions with three different sea ice models via two data assimilation methods. The work described here is the first example of assimilating remotely-sensed data within high-resolution and detailed dynamic-thermodynamic sea ice models. The results demonstrate that assimilation is a valuable resource for determining accurate ice motion in the Arctic.
Preliminary Modeling of Acoustic Detection Capability for the Drifting Arctic Monitoring System
2015-02-01
required. Active heating through chemical means is also a possibility, but will be avoided if possible due to the added complexity. The maximum buoy...2015-R021 [24] Engen , Øyvind, Gjengedal, Jakob Andreas, Faleide, Jan Inge, Kristoffersen, Yngve, and Eldholm, Olav (2009), Seismic stratigraphy and
NASA Astrophysics Data System (ADS)
Corlett, G. K.; Barton, I. J.; Donlon, C. J.; Edwards, M. C.; Good, S. A.; Horrocks, L. A.; Llewellyn-Jones, D. T.; Merchant, C. J.; Minnett, P. J.; Nightingale, T. J.; Noyes, E. J.; O'Carroll, A. G.; Remedios, J. J.; Robinson, I. S.; Saunders, R. W.; Watts, J. G.
The Advanced Along-Track Scanning Radiometer (AATSR) was launched on Envisat in March 2002. The AATSR instrument is designed to retrieve precise and accurate global sea surface temperature (SST) that, combined with the large data set collected from its predecessors, ATSR and ATSR-2, will provide a long term record of SST data that is greater than 15 years. This record can be used for independent monitoring and detection of climate change. The AATSR validation programme has successfully completed its initial phase. The programme involves validation of the AATSR derived SST values using in situ radiometers, in situ buoys and global SST fields from other data sets. The results of the initial programme presented here will demonstrate that the AATSR instrument is currently close to meeting its scientific objectives of determining global SST to an accuracy of 0.3 K (one sigma). For night time data, the analysis gives a warm bias of between +0.04 K (0.28 K) for buoys to +0.06 K (0.20 K) for radiometers, with slightly higher errors observed for day time data, showing warm biases of between +0.02 (0.39 K) for buoys to +0.11 K (0.33 K) for radiometers. They show that the ATSR series of instruments continues to be the world leader in delivering accurate space-based observations of SST, which is a key climate parameter.
Predicting the Extent of Summer Sea Ice in the Arctic
NASA Astrophysics Data System (ADS)
Rigor, I. G.; Wallace, J. M.
2003-12-01
The summers of 1998 and 2002 had the least sea ice extent (SIE) in the Arctic. These observations seem to agree with the trends noted by Parkinson, et al. (1999, hereafter P99) for the period 1979-1997, but the spatial pattern of these recent decreases in summer SIE were different. The summer trends shown by P99, exhibit large decreases in SIE primarily in the East Siberian Sea (ESS), while the decreases observed during 1998 and 2002 were much larger in the Beaufort and Chukchi seas (BCS). We now show that the trends for the period 1979 - 2002 are much smaller in the ESS than the trends shown by P99, and the largest decreasing trends have shifted from the ESS to the BCS. Rigor, et al. (2002) showed that the changes in SIE that P99 noted were driven by changes in atmospheric circulation related to the phase of the prior winter Arctic Oscillation (AO, Thompson and Wallace, 1998) index. Given that the latest trends in SIE are different than those shown by P99, one could ask whether the affect of the AO on sea ice noted by Rigor, et al. (2002) has also changed, and whether some large scale climate modes other than the AO has influenced the climate of the Arctic Ocean more? To answer these questions, we applied Empirical Orthogonal Function (EOF) analysis on the September SIE data from microwave satellites, and found that the first two modes SIE were most highly correlated to the prior winter AO, and the AO index of the summer months just prior to each September. These modes explain more than 45% of the variance in SIE, and show that the influence of the winter and summer AO dominates Arctic climate from 1979 - 2002. Using data from the International Arctic Buoy Programme and the National Centers for Environmental Prediction, we will show that the changes in sea ice extent are primarily driven by dynamic changes in sea ice thickness and discuss the implications for predicting summer SIE.
A Parameter Tuning Scheme of Sea-ice Model Based on Automatic Differentiation Technique
NASA Astrophysics Data System (ADS)
Kim, J. G.; Hovland, P. D.
2001-05-01
Automatic diferentiation (AD) technique was used to illustrate a new approach for parameter tuning scheme of an uncoupled sea-ice model. Atmospheric forcing field of 1992 obtained from NCEP data was used as enforcing variables in the study. The simulation results were compared with the observed ice movement provided by the International Arctic Buoy Programme (IABP). All of the numerical experiments were based on a widely used dynamic and thermodynamic model for simulating the seasonal sea-ice chnage of the main Arctic ocean. We selected five dynamic and thermodynamic parameters for the tuning process in which the cost function defined by the norm of the difference between observed and simulated ice drift locations was minimized. The selected parameters are the air and ocean drag coefficients, the ice strength constant, the turning angle at ice-air/ocean interface, and the bulk sensible heat transfer coefficient. The drag coefficients were the major parameters to control sea-ice movement and extent. The result of the study shows that more realistic simulations of ice thickness distribution was produced by tuning the simulated ice drift trajectories. In the tuning process, the L-BFCGS-B minimization algorithm of a quasi-Newton method was used. The derivative information required in the minimization iterations was provided by the AD processed Fortran code. Compared with a conventional approach, AD generated derivative code provided fast and robust computations of derivative information.
Proving and Improving Wave Models in the Arctic Ocean and its MIZ
2013-09-30
wave buoy was deployed in the ocean near the berg throughout the experiment, and recorded a persistent swell from the SE. An array of tiltmeters and GPS...vertical movement sensors was placed on the berg near the edge. These recorded the berg response to the waves, and on one occasion a calving event
NASA Astrophysics Data System (ADS)
Liu, Jiping; Zhang, Zhanhai; Hu, Yongyun; Chen, Liqi; Dai, Yongjiu; Ren, Xiaobo
2008-05-01
The surface air temperature (SAT) over the Arctic Ocean in reanalyses and global climate model simulations was assessed using the International Arctic Buoy Programme/Polar Exchange at the Sea Surface (IABP/POLES) observations for the period 1979-1999. The reanalyses, including the National Centers for Environmental Prediction Reanalysis II (NCEP2) and European Centre for Medium-Range Weather Forecast 40-year Reanalysis (ERA40), show encouraging agreement with the IABP/POLES observations, although some spatiotemporal discrepancies are noteworthy. The reanalyses have warm annual mean biases and underestimate the observed interannual SAT variability in summer. Additionally, NCEP2 shows an excessive warming trend. Most model simulations (coordinated by the International Panel on Climate Change for its Fourth Assessment Report) reproduce the annual mean, seasonal cycle, and trend of the observed SAT reasonably well, particularly the multi-model ensemble mean. However, large discrepancies are found. Some models have the annual mean SAT biases far exceeding the standard deviation of the observed interannul SAT variability and the across-model standard deviation. Spatially, the largest inter-model variance of the annual mean SAT is found over the North Pole, Greenland Sea, Barents Sea and Baffin Bay. Seasonally, a large spread of the simulated SAT among the models is found in winter. The models show interannual variability and decadal trend of various amplitudes, and can not capture the observed dominant SAT mode variability and cooling trend in winter. Further discussions of the possible attributions to the identified SAT errors for some models suggest that the model's performance in the sea ice simulation is an important factor.
Arctic air pollution: A Norwegian perspective
NASA Astrophysics Data System (ADS)
Ottar, B.
The paper gives a survey of the results obtained during a research programme in the Norwegian Arctic, financed by British Petroleum Ltd. during the period 1981-1986 under an agreement between the Norwegian Government and the oil companies. The programme included extensive measurement programmes by aircraft and at ground stations, as well as modelling of the transport of air pollutants to the Arctic. The results show that the Arctic plays an important role as an intermediate station in the general dispersion of air pollutants within the Northern Hemisphere. Continued measurements in the Arctic may therefore provide essential information concerning such questions as the change of climate and the global dispersion of polychlorinated hydrocarbons and other halogenated organics.
SSPARR: Development of an efficient autonomous sampling strategy
NASA Astrophysics Data System (ADS)
Chayes, D. N.
2013-12-01
The Seafloor Sounding in Polar and Remote Regions (SSPARR) effort was launched in 2004 with funding from the US National Science Foundation (Anderson et al. 2005.) Experiments with a prototype were encouraging (Greenspan et al., 2012, Chayes et al. 2012) and we are proceeding toward building and testing units for deployment during the 2014 season season in ice covered parts of the Arctic ocean. The simplest operational mode for a SSPARR buoy will be to wake and sample on a fixed time interval. A slightly more complex mode will check the distance traveled since the pervious sounding and potentially return to sleep-mode if it has not traveled far enough to make a significant new measurement. We are developing a mode that will use a sampling strategy based on querying an on-board copy of the best available digital terrain model (DTM) e.g. IBCAO in the Arctic, to help decide if it is appropriate to turn on the echo sounder and make a new measurement. We anticipate that a robust strategy of this type will allow a buoy to operate substantially longer on a fixed battery size. Anderson, R., D. Chayes, et al. (2005). "Seafloor Soundings in Polar and Remote Regions - A new instrument for unattended bathymetric observations," Eos Trans. AGU 86(18): Abstract C43A-10. Greenspan, D., D. Porter, et al. (2012). "IBuoy: Expendable Echo Sounder Buoy with Satellite Telemetry." EOS Fall Meeting Supplement C13E-0660. Chayes, D. N., S. A. Goemmer, et al. (2012). "SSPARR-3: A cost-effective autonomous drifting echosounder." EOS Fall Meeting supplement C13E-0659.
High-precision GPS autonomous platforms for sea ice dynamics and physical oceanography
NASA Astrophysics Data System (ADS)
Elosegui, P.; Wilkinson, J.; Olsson, M.; Rodwell, S.; James, A.; Hagan, B.; Hwang, B.; Forsberg, R.; Gerdes, R.; Johannessen, J.; Wadhams, P.; Nettles, M.; Padman, L.
2012-12-01
Project "Arctic Ocean sea ice and ocean circulation using satellite methods" (SATICE), is the first high-rate, high-precision, continuous GPS positioning experiment on sea ice in the Arctic Ocean. The SATICE systems collect continuous, dual-frequency carrier-phase GPS data while drifting on sea ice. Additional geophysical measurements also collected include ocean water pressure, ocean surface salinity, atmospheric pressure, snow-depth, air-ice-ocean temperature profiles, photographic imagery, and others, enabling sea ice drift, freeboard, weather, ice mass balance, and sea-level height determination. Relatively large volumes of data from each buoy are streamed over a satellite link to a central computer on the Internet in near real time, where they are processed to estimate the time-varying buoy positions. SATICE system obtains continuous GPS data at sub-minute intervals with a positioning precision of a few centimetres in all three dimensions. Although monitoring of sea ice motions goes back to the early days of satellite observations, these autonomous platforms bring out a level of spatio-temporal detail that has never been seen before, especially in the vertical axis. These high-resolution data allows us to address new polar science questions and challenge our present understanding of both sea ice dynamics and Arctic oceanography. We will describe the technology behind this new autonomous platform, which could also be adapted to other applications that require high resolution positioning information with sustained operations and observations in the polar marine environment, and present results pertaining to sea ice dynamics and physical oceanography.
Evaluation of Sea Ice Kinematics and their Impact on Ice Thickness Distribution in the Arctic
2012-03-01
operational and research data to interested users. The position error for these buoys has been estimated as 0.3 km by Thorndike and Colony (1980...1297–1300. ———, and ———,1999: Annular Modes in the Extratropical Circulations. Part II: Trends. J. Clim., 13, 1018–1036. Thorndike , A. S., and R
Changes in the Arctic: Background and Issues for Congress
2014-04-28
knowledge of the physical environment. Data must be obtained by a suite of remote sensors (satellites, radars), autonomous sensors (data buoys...unmanned vehicles), and manned sensors (shipboard, coastal observing stations). Computer-based ocean and atmospheric models must be adjusted to the... soot ). 6. Implementation: In carrying out this policy as it relates to environmental protection and conservation of natural resources, the
Recently amplified arctic warming has contributed to a continual global warming trend
NASA Astrophysics Data System (ADS)
Huang, Jianbin; Zhang, Xiangdong; Zhang, Qiyi; Lin, Yanluan; Hao, Mingju; Luo, Yong; Zhao, Zongci; Yao, Yao; Chen, Xin; Wang, Lei; Nie, Suping; Yin, Yizhou; Xu, Ying; Zhang, Jiansong
2017-12-01
The existence and magnitude of the recently suggested global warming hiatus, or slowdown, have been strongly debated1-3. Although various physical processes4-8 have been examined to elucidate this phenomenon, the accuracy and completeness of observational data that comprise global average surface air temperature (SAT) datasets is a concern9,10. In particular, these datasets lack either complete geographic coverage or in situ observations over the Arctic, owing to the sparse observational network in this area9. As a consequence, the contribution of Arctic warming to global SAT changes may have been underestimated, leading to an uncertainty in the hiatus debate. Here, we constructed a new Arctic SAT dataset using the most recently updated global SATs2 and a drifting buoys based Arctic SAT dataset11 through employing the `data interpolating empirical orthogonal functions' method12. Our estimate of global SAT rate of increase is around 0.112 °C per decade, instead of 0.05 °C per decade from IPCC AR51, for 1998-2012. Analysis of this dataset shows that the amplified Arctic warming over the past decade has significantly contributed to a continual global warming trend, rather than a hiatus or slowdown.
New data from cold war treasure trove
NASA Astrophysics Data System (ADS)
Carlowicz, Michael
For half a century, the Russian and United States navies competed for tactical advantage in the Arctic Ocean, mapping seafloor and floating ice sheets, measuring temperatures and reckoning chemistry. But with old enemies becoming new friends, data once collected for the sake of war now are being shared in the name of scientific cooperation.In mid-January, the U.S. and Russian governments announced the release of the first of four volumes of a new atlas of the Arctic Ocean. The previously classified data it contains will effectively double the amount of Arctic data that is available to the scientific community. The set includes more than 1.3 million temperature and salinity observations collected from 1948 to 1993 by drifting ice camps and stations, icebreaking ships, land—and airborne expeditions, and buoys. Approximately 70% of the observations for the Arctic Ocean and shelf seas were derived from Russian archives of formerly restricted data, with the other 30% coming from comparable sources in the U.S., Canada, and other Western nations.
NASA Astrophysics Data System (ADS)
Mahoney, A. R.; Kasper, J.; Winsor, P.
2015-12-01
Highly complex patterns of ice motion and deformation were captured by fifteen satellite-telemetered GPS buoys (known as Ice Trackers) deployed near Barrow, Alaska, in spring 2015. Two pentagonal clusters of buoys were deployed on pack ice by helicopter in the Beaufort Sea between 20 and 80 km offshore. During deployment, ice motion in the study region was effectively zero, but two days later the buoys captured a rapid transport event in which multiyear ice from the Beaufort Sea was flushed into the Chukchi Sea. During this event, westward ice motion began in the Chukchi Sea and propagated eastward. This created new openings in the ice and led to rapid elongation of the clusters as the westernmost buoys accelerated away from their neighbors to the east. The buoys tracked ice velocities of over 1.5 ms-1, with fastest motion occurring closest to the coast indicating strong current shear. Three days later, ice motion reversed and the two clusters became intermingled, rendering divergence calculations based on the area enclosed by clusters invalid. The data show no detectable difference in velocity between first year and multiyear ice floes, but Lagrangian timeseries of SAR imagery centered on each buoy show that first year ice underwent significant small-scale deformation during the event. The five remaining buoys were deployed by local residents on prominent ridges embedded in the landfast ice within 16 km of Barrow in order to track the fate of such features after they detached from the coast. Break-up of the landfast ice took place over a period of several days and, although the buoys each initially followed a similar eastward trajectory around Point Barrow into the Beaufort Sea, they rapidly dispersed over an area more than 50 km across. With rapid environmental and socio-economic change in the Arctic, understanding the complexity of nearshore ice motion is increasingly important for predict future changes in the ice and the tracking ice-related hazards contaminants entrained in the ice. This work demonstrates the ability of low-cost easily-deployable Ice Trackers to generate to generate data of both scientific and operational value.
Assessing, understanding, and conveying the state of the Arctic sea ice cover
NASA Astrophysics Data System (ADS)
Perovich, D. K.; Richter-Menge, J. A.; Rigor, I.; Parkinson, C. L.; Weatherly, J. W.; Nghiem, S. V.; Proshutinsky, A.; Overland, J. E.
2003-12-01
Recent studies indicate that the Arctic sea ice cover is undergoing significant climate-induced changes, affecting both its extent and thickness. Satellite-derived estimates of Arctic sea ice extent suggest a reduction of about 3% per decade since 1978. Ice thickness data from submarines suggest a net thinning of the sea ice cover since 1958. Changes (including oscillatory changes) in atmospheric circulation and the thermohaline properties of the upper ocean have also been observed. These changes impact not only the Arctic, but the global climate system and are likely accelerated by such processes as the ice-albedo feedback. It is important to continue and expand long-term observations of these changes to (a) improve the fundamental understanding of the role of the sea ice cover in the global climate system and (b) use the changes in the sea ice cover as an early indicator of climate change. This is a formidable task that spans a range of temporal and spatial scales. Fortunately, there are numerous tools that can be brought to bear on this task, including satellite remote sensing, autonomous buoys, ocean moorings, field campaigns and numerical models. We suggest the integrated and coordinated use of these tools during the International Polar Year to monitor the state of the Arctic sea ice cover and investigate its governing processes. For example, satellite remote sensing provides the large-scale snapshots of such basic parameters as ice distribution, melt zone, and cloud fraction at intervals of half a day to a week. Buoys and moorings can contribute high temporal resolution and can measure parameters currently unavailable from space including ice thickness, internal ice temperature, and ocean temperature and salinity. Field campaigns can be used to explore, in detail, the processes that govern the ice cover. Numerical models can be used to assess the character of the changes in the ice cover and predict their impacts on the rest of the climate system. This work affords extraordinary opportunities for outreach activities, because of the public interest in both the Arctic and climate change. Data can be streamed to public web sites in near real time, as can photographs and commentaries from field camps. The breadth of activities affords considerable opportunities to engage the next generation of researchers in such diverse fields as computer science, engineering, and geophysics.
The Detection of Change in the Arctic Using Satellite and Buoy Data
NASA Technical Reports Server (NTRS)
Comiso, Josefino C.; Yang, J.; Honjo, S.; Krishfield, R.; Koblinsky, Chester J. (Technical Monitor)
2001-01-01
The decade of the 1990s is the warmest decade of the last century while the year 1998 is the warmest year ever observed by modern techniques with 9 out of 12 months of the year being the warmest month. Since the Arctic is expected to provide early signals of a possible warming scenario, detailed examination of changes in the Arctic environment is important. In this study, we examined available satellite ice cover and surface temperature data, wind and pressure data, and ocean hydrographic data to gain insights into the warming phenomenon. The areas of open water in both western and eastern regions of the Arctic were found to follow a cyclical pattern with approximately decadal period but with a lag of about three years between the two regions. The pattern was interrupted by unusually large anomalies in open water area in the western region in 1993 and 1998 and in the eastern region in 1995. The big 1998 open water anomaly occurred at the same time when a large surface temperature anomaly was also occurring in the area and adjacent regions. The infrared temperature data show for the first time the complete spatial scope of the warming anomalies and it is apparent that despite the magnitude of the 1998 anomaly, it is basically confined to North America and the Western Arctic. The large increases in open water areas in the Western Sector form 1996 to 1998 were observed to be coherent with changing wind directions which was predominantly cyclonic in 1996 and anti-cyclonic in 1997 and 1998. Detailed hydrography measurements up to 500 m depth over the same general area in April 1996 and April 1997 also indicate significant freshening and warming in the upper part of the mixed layer suggesting increases in ice melt. Continuous ocean temperature and salinity data from ocean buoys confirm this result and show significant seasonal changes from 1996 to 1998, at depths of 8 m, 45 m, and 75 m. Long data records of temperature and hydrography were also examined and the potential impact of a warming, freshening, and the presence of abnormally large open areas on the state of the Arctic climate system are discussed.
UpTempO Buoys for Understanding and Prediction
2015-09-30
to better understand the evolution of heat content in the upper Arctic Ocean within the Seasonal Ice Zone (SIZ), both seasonally during summer...warming and fall cooling, and interannually as sea ice retreats and the warming season lengthens. The effort is a contribution to the multi-investigator...along 140W on SIZRS flights. These were: • One 2013 model held from the previous field season • One 2014 model with spherical hull • Two 2014
Coordination and Data Management of the International Arctic Buoy Program
1997-09-30
which can drive sea ice models , and for input into climate change studies. Recent research using the IABP databases includes back and forward trajectory...present. Figure 2 shows the mean annual field of ice motion and sea level pressure. APPROACH Coordination of the IABP falls into the categories of...products of the IABP are now also available on the World Wide Web. Our recent efforts to improve the database have been directed towards producing a
Observing Radiative Properties of a Thinner, Seasonal Arctic Ice Pack
NASA Astrophysics Data System (ADS)
Hudson, S. R.; Nicolaus, M.; Granskog, M.; Gerland, S.; Wang, C.
2011-12-01
The Arctic is coming to be dominated by young ice, much of it seasonal. Many of our observations of the radiative properties of sea ice come from drifting stations on thick, multi-year ice. To better understand the Arctic climate system in a warmer world, we need more data about the radiative properties and their seasonal and spatial variability on thinner, younger ice. Since this younger ice is not always thick enough to support lengthy drifting stations, there is a need for new technologies to help us get optical measurements on seasonal ice. One challenge is obtaining seasonal data on ice that is too weak to support even a ship-based camp, and especially to have these observations extend well into the melt season. For these situations, we have developed a spectral radiation monitoring buoy that can be deployed during a one-day ice station, and that can then autonomously observe the spectral albedo and transmittance of the sea ice, transmitting all data in near real time by satellite, until the buoy melts out. Similar installations at manned or regularly visited sites have provided good data, with surprisingly few data-quality problems due to frost, precipitation, or tilting. The buoys consist of 3 spectral radiometers, covering wavelengths 350 to 800 nm, and a datalogger with an Irridium modem. The datalogger and necessary batteries are inside a sealed housing which is frozen into a hole drilled in the ice. Arms extend from both the top and bottom of the housing, holding sensors that measure incident, reflected, and transmitted spectra. The under-ice radiometer is equipped with a bioshutter to avoid algal growth on the sensor. They will be deployed alongside ice mass balance buoys, providing data about the physical development of the ice and snow, as well as position. While the buoys provide an excellent record of diurnal, synoptic, and seasonal variability, they are fixed to one location in the ice, so other methods are still needed for measuring the spatial variability. For this, we have developed a radiation sled for measuring the full radiation budget of sea ice at a grid of locations to observe the variability within an area similar to a satellite pixel or model grid cell. Based on a modified dog sled, it carries upward and downward looking longwave and shortwave broadband radiometers, a spectral radiometer (350 to 2500 nm) for measuring spectral albedo, cameras to record surface and ground conditions at each measurement site, a thermometer, hygrometer, and GPS. Small enough to be deployed from a ship at short ice stations, it can also be used at longer stations to observe the effect of the spatial variability on the temporal variability. When combined with measurements or estimates of the sensible and latent heat fluxes, a full picture of the large-scale energy budget and its small-scale variations is obtained, valuable insight for parameterization and remote sensing product development. Surface profiles with the sled can be complemented by under-ice profiles made with a spectral radiometer mounted on an ROV or carried by a diver, providing a measure of the spatial variability of the partitioning of the absorbed solar energy into the ice and water.
Proving and Improving Wave Models in the Arctic Ocean and its MIZ
2014-09-30
on a giant ice island in Baffin Bay, in which the response to a breakup event was measured and the size of the broken-out iceberg fragment tested...2014), In situ measurements and analysis of ocean waves in the Antarctic marginal ice zone, Geophys. Res. Lett., 41, 5046–5051, doi:10.1002...Symposium on Ice, Singapore, August 11 to 15, 2014. Doble, M. J., and J.-R. Bidlot, 2013. Wave buoy measurements at the Antarctic sea ice edge
2. Spar, bramble, and the larger cutters storis (W38) make ...
2. Spar, bramble, and the larger cutters storis (W38) make their way through arctic ice during the first transit of the northwest passage by a U.S. vessel. The lead 180 has a weight suspended over its starboard side. By swinging this weight back and forth across the centerline, the vessel can rock to free herself from ice. - U.S. Coast Guard Buoy Tenders, 180' Class, U.S. Coast Guard Headquarters, 2100 Second Street Southwest, Washington, District of Columbia, DC
NASA Astrophysics Data System (ADS)
Wright, N.; Polashenski, C. M.; Deeb, E. J.; Morriss, B. F.; Song, A.; Chen, J.
2015-12-01
One of the key processes controlling sea ice mass balance in the Arctic is the partitioning of solar energy between reflection back to the atmosphere and absorption into the ice and upper ocean. We investigate the solar energy balance in the ice-ocean system using in-situ data collected from Arctic Observing Network (AON) sea ice sites and imagery from high resolution optical satellites. AON assets, including ice mass balance buoys and ice tethered profilers, monitor the storage and fluxes of heat in the ice-ocean system. High resolution satellite imagery, processed using object-based image classification techniques, allows us to quantify the evolution of surrounding ice conditions, including melt pond coverage and floe size distribution, at aggregate scale. We present results from regionally representative sites that constrain the partitioning of absorbed solar energy between ice melt and ocean storage, and quantify the strength of the ice-albedo feedback. We further demonstrate how the results can be used to validate model representations of the physical processes controlling ice-albedo feedbacks. The techniques can be extended to understand solar partitioning across the Arctic basin using additional sites and model based data integration.
The statistical properties of sea ice velocity fields
NASA Astrophysics Data System (ADS)
Agarwal, S.; Wettlaufer, J. S.
2016-12-01
Thorndike and Colony (1982) showed that more than 70% of the variance of the ice motion can be explained by the geostrophic winds. This conclusion was reached by analyzing only 2 years of data. Due to the importance of ice motion in Arctic climate we ask how persistent is such a prediction. In so doing, we study and develop a stochastic model for the Arctic sea ice velocity fields based on the observed sea ice velocity fields from satellites and buoys for the period 1978 - 2012. Having previously found that the Arctic Sea Equivalent Ice Extent (EIE) has a white noise structure on annual to bi-annual time scales (Agarwal et. al. 2012), we assess the connection to ice motion. We divide the Arctic into dynamic and thermodynamic components, with focus on the dynamic part i.e. the velocity fields of sea ice driven by the geostrophic winds over the Arctic. We show (1) the stationarity of the spatial correlation structure of the velocity fields, and (2) the robustness of white noise structure present in the velocity fields on annual to bi-annual time scales, which combine to explain the white noise characteristics of the EIE on these time scales. S. Agarwal, W. Moon and J.S. Wettlaufer, Trends, noise and reentrant long-term persistence in Arctic sea ice, Proc. R. Soc. A, 468, 2416 (2012). A.S. Thorndike and R. Colony, Sea ice motion in response to geostrophic winds, J. Geophys. Res. 87, 5845 (1982).
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.
NASA Astrophysics Data System (ADS)
Stanton, T. P.; Shaw, W. J.
2014-12-01
Since 2002, a series of 28 Autonomous Ocean Flux Buoys have been deployed in the Beaufort Sea and from the North Pole Environmental Observatory. These long-term ice-deployed instrument systems primarily measure vertical turbulent fluxes of heat, salt and momentum at a depth of 2 - 6 m below the ocean/ice interface, while concurrently measuring current profile every 2m down to approximately 40-50m depth, within the seasonal pycnocline. Additional sensors have been added to measure local ice melt rates acoustically, and finescale thermal structure from the eddy correlation flux sensor up into the ice to resolve summer near-surface heating. The AOFB buoys have typically been co-located with Ice Tethered Profilers, that measure the upper ocean T/S structure and ice mass balance instruments. Comparisons of near-surface heat fluxes, heat content and vertical structure over the last decade will be made for buoys in the Beaufort Sea and Transpolar Drift between the North Pole and Spitzbergen. The effects of enhanced basal melting from ice/albedo feedbacks can be clearly seen in the low ice concentration summer conditions found more recently in the Beaufort Sea, while there are less pronounced effects of enhanced summer surface heating in the higher ice concentrations still found in the transpolar drift.
NASA Astrophysics Data System (ADS)
Rösel, Anja; Itkin, Polona; King, Jennifer; Divine, Dmitry; Wang, Caixin; Granskog, Mats A.; Krumpen, Thomas; Gerland, Sebastian
2018-02-01
In recent years, sea-ice conditions in the Arctic Ocean changed substantially toward a younger and thinner sea-ice cover. To capture the scope of these changes and identify the differences between individual regions, in situ observations from expeditions are a valuable data source. We present a continuous time series of in situ measurements from the N-ICE2015 expedition from January to June 2015 in the Arctic Basin north of Svalbard, comprising snow buoy and ice mass balance buoy data and local and regional data gained from electromagnetic induction (EM) surveys and snow probe measurements from four distinct drifts. The observed mean snow depth of 0.53 m for April to early June is 73% above the average value of 0.30 m from historical and recent observations in this region, covering the years 1955-2017. The modal total ice and snow thicknesses, of 1.6 and 1.7 m measured with ground-based EM and airborne EM measurements in April, May, and June 2015, respectively, lie below the values ranging from 1.8 to 2.7 m, reported in historical observations from the same region and time of year. The thick snow cover slows thermodynamic growth of the underlying sea ice. In combination with a thin sea-ice cover this leads to an imbalance between snow and ice thickness, which causes widespread negative freeboard with subsequent flooding and a potential for snow-ice formation. With certainty, 29% of randomly located drill holes on level ice had negative freeboard.
ERIC Educational Resources Information Center
Hodgkins, Andrew P.
2015-01-01
This article examines a federally funded pre-apprenticeship training programme designed to transition aboriginal northerners living in the Canadian Arctic into trades-related employment. Drawing from interviews involving programme partners and stakeholders, the Aboriginal Skills and Employment Partnership programme that operated in the Beaufort…
AROME-Arctic: New operational NWP model for the Arctic region
NASA Astrophysics Data System (ADS)
Süld, Jakob; Dale, Knut S.; Myrland, Espen; Batrak, Yurii; Homleid, Mariken; Valkonen, Teresa; Seierstad, Ivar A.; Randriamampianina, Roger
2016-04-01
In the frame of the EU-funded project ACCESS (Arctic Climate Change, Economy and Society), MET Norway aimed 1) to describe the present monitoring and forecasting capabilities in the Arctic; and 2) to identify the key factors limiting the forecasting capabilities and to give recommendations on key areas to improve the forecasting capabilities in the Arctic. We have observed that the NWP forecast quality is lower in the Arctic than in the regions further south. Earlier research indicated that one of the factors behind this is the composition of the observing system in the Arctic, in particular the scarceness of conventional observations. To further assess possible strategies for alleviating the situation and propose scenarios for a future Arctic observing system, we have performed a set of experiments to gain a more detailed insight in the contribution of the components of the present observing system in a regional state-of-the-art non-hydrostatic NWP model using the AROME physics (Seity et al, 2011) at 2.5 km horizontal resolution - AROME-Arctic. Our observing system experiment studies showed that conventional observations (Synop, Buoys) can play an important role in correcting the surface state of the model, but prove that the present upper-air conventional (Radiosondes, Aircraft) observations in the area are too scarce to have a significant effect on forecasts. We demonstrate that satellite sounding data play an important role in improving forecast quality. This is the case with satellite temperature sounding data (AMSU-A, IASI), as well as with the satellite moisture sounding data (AMSU-B/MHS, IASI). With these sets of observations, the AROME-Arctic clearly performs better in forecasting extreme events, like for example polar lows. For more details see presentation by Randriamampianina et al. in this session. The encouraging performance of AROME-Arctic lead us to implement it with more observations and improved settings into daily runs with the objective to substitute our actual operational Arctic mesoscale HIRLAM (High Resolution Limited Area Model) NWP model. This presentation will discuss in detail the operational implementation of the AROME-Arctic model together with post-processing methods. Aimed services in the Arctic region covered by the model, such as online weather forecasting (yr.no) and tracking of polar lows (barentswatch.no), is also included.
Civil engineering in the Arctic offshore
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bennett, F.L.; Machemehl, J.L.
1985-01-01
This book presents the current state of practice and theory in the civil engineering aspects of offshore development in the Arctic. It also covers the emerging concepts and requirements, research and development needs, and a critique of present undergraduate programmes.
Squaring the Arctic Circle: connecting Arctic knowledge with societal needs
NASA Astrophysics Data System (ADS)
Wilkinson, J.
2017-12-01
Over the coming years the landscape of the Arctic will change substantially- environmentally, politically, and economically. Furthermore, Arctic change has the potential to significantly impact Arctic and non-Arctic countries alike. Thus, our science is in-demand by local communities, politicians, industry leaders and the public. During these times of transition it is essential that the links between science and society be strengthened further. Strong links between science and society is exactly what is needed for the development of better decision-making tools to support sustainable development, enable adaptation to climate change, provide the information necessary for improved management of assets and operations in the Arctic region, and and to inform scientific, economic, environmental and societal policies. By doing so tangible benefits will flow to Arctic societies, as well as for non-Arctic countries that will be significantly affected by climate change. Past experience has shown that the engagement with a broad range of stakeholders is not always an easy process. Consequently, we need to improve collaborative opportunities between scientists, indigenous/local communities, private sector, policy makers, NGOs, and other relevant stakeholders. The development of best practices in this area must build on the collective experiences of successful cross-sectorial programmes. Within this session we present some of the outreach work we have performed within the EU programme ICE-ARC, from community meetings in NW Greenland through to sessions at the United Nations Framework Convention on Climate Change COP Conferences, industry round tables, and an Arctic side event at the World Economic Forum in Davos.
NASA Astrophysics Data System (ADS)
Kassin, A.; Cody, R. P.; Barba, M.; Escarzaga, S. M.; Villarreal, S.; Manley, W. F.; Gaylord, A. G.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.
2017-12-01
To better assess progress in Arctic Observing made by U.S. SEARCH, NSF AON, SAON, and related initiatives, an updated version of the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been released. This web mapping application and information system conveys the who, what, where, and when of "data collection sites" - the precise locations of monitoring assets, observing platforms, and wherever repeat marine or terrestrial measurements have been taken. Over 13,000 sites across the circumarctic are documented including a range of boreholes, ship tracks, buoys, towers, sampling stations, sensor networks, vegetation plots, stream gauges, ice cores, observatories, and more. Contributing partners are the U.S. NSF, NOAA, the NSF Arctic Data Center, ADIwg, AOOS, a2dc, CAFF, GINA, IASOA, INTERACT, NASA ABoVE, and USGS, among others. Users can visualize, navigate, select, search, draw, print, view details, and follow links to obtain a comprehensive perspective of environmental monitoring efforts. We continue to develop, populate, and enhance AOV. Recent updates include: a vastly improved Search tool with free text queries, autocomplete, and filters; faster performance; a new clustering visualization; heat maps to highlight concentrated research; and 3-D represented data to more easily identify trends. AOV is founded on principles of interoperability, such that agencies and organizations can use the AOV Viewer and web services for their own purposes. In this way, AOV complements other distributed yet interoperable cyber resources and helps science planners, funding agencies, investigators, data specialists, and others to: assess status, identify overlap, fill gaps, optimize sampling design, refine network performance, clarify directions, access data, coordinate logistics, and collaborate to meet Arctic Observing goals. AOV is a companion application to the Arctic Research Mapping Application (armap.org), which is focused on general project information at a coarser level of granularity.
Influences of Ocean Thermohaline Stratification on Arctic Sea Ice
NASA Astrophysics Data System (ADS)
Toole, J. M.; Timmermans, M.-L.; Perovich, D. K.; Krishfield, R. A.; Proshutinsky, A.; Richter-Menge, J. A.
2009-04-01
The Arctic Ocean's surface mixed layer constitutes the dynamical and thermodynamical link between the sea ice and the underlying waters. Wind stress, acting directly on the surface mixed layer or via wind-forced ice motion, produce surface currents that can in turn drive deep ocean flow. Mixed layer temperature is intimately related to basal sea ice growth and melting. Heat fluxes into or out of the surface mixed layer can occur at both its upper and lower interfaces: the former via air-sea exchange at leads and conduction through the ice, the latter via turbulent mixing and entrainment at the layer base. Variations in Arctic Ocean mixed layer properties are documented based on more than 16,000 temperature and salinity profiles acquired by Ice-Tethered Profilers since summer 2004 and analyzed in conjunction with sea ice observations from Ice Mass Balance Buoys and atmospheric heat flux estimates. Guidance interpreting the observations is provided by a one-dimensional ocean mixed layer model. The study focuses attention on the very strong density stratification about the mixed layer base in the Arctic that, in regions of sea ice melting, is increasing with time. The intense stratification greatly impedes mixed layer deepening by vertical convection and shear mixing, and thus limits the flux of deep ocean heat to the surface that could influence sea ice growth/decay. Consistent with previous work, this study demonstrates that the Arctic sea ice is most sensitive to changes in ocean mixed layer heat resulting from fluxes across its upper (air-sea and/or ice-water) interface.
NASA Astrophysics Data System (ADS)
Lei, Ruibo; Cheng, Bin; Heil, Petra; Vihma, Timo; Wang, Jia; Ji, Qing; Zhang, Zhanhai
2018-04-01
The seasonal evolution of sea ice mass balance between the Central Arctic and Fram Strait, as well as the underlying driving forces, remain largely unknown because of a lack of observations. In this study, two and three buoys were deployed in the Central Arctic during the summers of 2010 and 2012, respectively. It was established that basal ice growth commenced between mid-October and early December. Annual basal ice growth, ranging from 0.21 to 1.14 m, was determined mainly by initial ice thickness, air temperature, and oceanic heat flux during winter. An analytic thermodynamic model indicated that climate warming reduces the winter growth rate of thin ice more than for thick ice because of the weak thermal inertia of the former. Oceanic heat flux during the freezing season was 2-4 W m-2, which accounted for 18-31% of the basal ice energy balance. We identified two mechanisms that modified the oceanic heat flux, i.e., solar energy absorbed by the upper ocean during summer, and interaction with warm waters south of Fram Strait; the latter resulted in basal ice melt, even in winter. In summer 2010, ice loss in the Central Arctic was considerable, which led to increased oceanic heat flux into winter and delayed ice growth. The Transpolar Drift Stream was relatively weak in summer 2013. This reduced sea ice advection out of the Arctic Ocean, and it restrained ice melt because of the cool atmospheric conditions, weakened albedo feedback, and relatively small oceanic heat flux in the north.
Rainy Days in the New Arctic: A Comprehensive Look at Precipitation from 8 Reanalysis
NASA Astrophysics Data System (ADS)
Boisvert, L.; Webster, M.; Petty, A.; Markus, T.
2017-12-01
Precipitation in the Arctic plays an important role in the fresh water budget, and is the primary control of snow accumulation on sea ice. However, Arctic precipitation from reanalysis is highly uncertain due to differences in the atmospheric physics and use/approaches of data assimilation and sea ice concentrations across the different products. More specifically, yearly cumulative precipitation in some regions can vary by 100-150 mm across reanalyses. This creates problems for those modeling snow depth on sea ice, specifically for use in deriving sea ice thickness from satellite altimetry. In recent years, this new Arctic has become warmer and wetter, and evaporation from the ice-free ocean has been increasing, which leads to the question: is more precipitation falling and is more of this precipitation rain? This could pose a big problem for model and remote sensing applications and studies those modeling snow accumulation because rain events will can melt the existing snow pack, reduce surface albedo, and modify the ocean-to-atmosphere heat flux via snow densification. In this work we compare precipitation (both snow and rain) from 8 different reanalysis: MERRA, MERRA2, NCEP-R1, NCEP-R2, ERA-Interim, ERA-5, ASR and JRA-55. We examine the annual, seasonal, and regional differences and compare with buoy data to assess discrepancies between products during observed snowfall and rainfall events. Magnitudes and frequencies of these precipitation events are evaluated, as well as the "residual drizzle" between reanalyzes. Lastly, we will look at whether the frequency and magnitude of "rainy days" in the Arctic have been changing over recent decades.
NASA Astrophysics Data System (ADS)
Girard, L.; Weiss, J.; Molines, J. M.; Barnier, B.; Bouillon, S.
2009-08-01
Sea ice drift and deformation from models are evaluated on the basis of statistical and scaling properties. These properties are derived from two observation data sets: the RADARSAT Geophysical Processor System (RGPS) and buoy trajectories from the International Arctic Buoy Program (IABP). Two simulations obtained with the Louvain-la-Neuve Ice Model (LIM) coupled to a high-resolution ocean model and a simulation obtained with the Los Alamos Sea Ice Model (CICE) were analyzed. Model ice drift compares well with observations in terms of large-scale velocity field and distributions of velocity fluctuations although a significant bias on the mean ice speed is noted. On the other hand, the statistical properties of ice deformation are not well simulated by the models: (1) The distributions of strain rates are incorrect: RGPS distributions of strain rates are power law tailed, i.e., exhibit "wild randomness," whereas models distributions remain in the Gaussian attraction basin, i.e., exhibit "mild randomness." (2) The models are unable to reproduce the spatial and temporal correlations of the deformation fields: In the observations, ice deformation follows spatial and temporal scaling laws that express the heterogeneity and the intermittency of deformation. These relations do not appear in simulated ice deformation. Mean deformation in models is almost scale independent. The statistical properties of ice deformation are a signature of the ice mechanical behavior. The present work therefore suggests that the mechanical framework currently used by models is inappropriate. A different modeling framework based on elastic interactions could improve the representation of the statistical and scaling properties of ice deformation.
UAV Deployed Sensor System for Arctic Ocean Remote Sensing
NASA Astrophysics Data System (ADS)
Palo, S. E.; Lawrence, D.; Weibel, D.; LoDolce, G.; Krist, S.; Crocker, I.; Maslanik, J. A.
2012-12-01
The Marginal Ice Zone Observations and Processes Experiment (MIZOPEX), is an Arctic field project scheduled for summer 2013. The goals of the project are to understand how warming of the marginal ice zone affects sea ice melt and if this warming has been over or underestimated by satellite measurements. To achieve these goals calibrated physical measurements, both remote and in-situ, of the marginal ice zone over scales of square kilometers with a resolution of square meters is required. This will be accomplished with a suite of unmanned aerial vehicles (UAVs) equipped with both remote sensing and in-situ instruments, air deployed microbuoys, and ship deployed buoys. In this talk we will present details about the air-deployed micro-buoy (ADMB) and self-deployed surface-sonde (SDSS) components of the MIZOPEX project, developed at the University of Colorado. These systems were designed to explore the potential of low-cost, on-demand access to high-latitude areas of important scientific interest. Both the ADMB and SDSS share a common measurement suite with the capability to measure water temperature at three distinct depths and provide position information via GPS. The ADMBs are dropped from the InSitu ScanEagle UAV and expected to operate and log ocean temperatures for 14 days. The SDSS are micro UAVs that are designed to fly one-way to a region of interest and land at specified coordinates, thereafter becoming a surface sensor similar to the ADMB. A ScanEagle will periodically return to the deployment zone to gather ADMB/SDSS data via low power radio links. Design decisions based upon operational constraints and the current status of the ADMB and SDSS will be presented.
The challenges of marine spatial planning in the Arctic: Results from the ACCESS programme.
Edwards, Rosemary; Evans, Alan
2017-12-01
Marine spatial planning is increasingly used to manage the demands on marine areas, both spatially and temporally, where several different users may compete for resources or space, to ensure that development is as sustainable as possible. Diminishing sea-ice coverage in the Arctic will allow for potential increases in economic exploitation, and failure to plan for cross-sectoral management could have negative economic and environmental results. During the ACCESS programme, a marine spatial planning tool was developed for the Arctic, enabling the integrated study of human activities related to hydrocarbon exploitation, shipping and fisheries, and the possible environmental impacts, within the context of the next 30 years of climate change. In addition to areas under national jurisdiction, the Arctic Ocean contains a large area of high seas. Resources and ecosystems extend across political boundaries. We use three examples to highlight the need for transboundary planning and governance to be developed at a regional level.
NASA Astrophysics Data System (ADS)
Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Kassin, A.; Villarreal, S.; Barba, M.; Dover, M.; Escarzaga, S. M.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.
2016-12-01
To better assess progress in Arctic Observing made by U.S. SEARCH, NSF AON, SAON, and related initiatives, an updated version of the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been released. This web mapping application and information system conveys the who, what, where, and when of "data collection sites" - the precise locations of monitoring assets, observing platforms, and wherever repeat marine or terrestrial measurements have been taken. Over 8000 sites across the circum-arctic are documented including a range of boreholes, ship tracks, buoys, towers, sampling stations, sensor networks, vegetation plots, stream gauges, ice cores, observatories, and more. Contributing partners are the U.S. NSF, ACADIS, ADIwg, AOOS, a2dc, AON, CAFF, GINA, IASOA, INTERACT, NASA ABoVE, and USGS, among others. Users can visualize, navigate, select, search, draw, print, view details, and follow links to obtain a comprehensive perspective of environmental monitoring efforts. We continue to develop, populate, and enhance AOV. Recent improvements include: a more intuitive and functional search tool, a modern cross-platform interface using javascript and HTML5, and hierarchical ISO metadata coupled with RESTful web services & metadata XLinks to span the data life cycle (from project planning to establishment of data collection sites to release of scientific datasets). Additionally, through collaborations with the Barrow Area Information Database (BAID, www.barrowmapped.org) we are exploring linkages with datacenters and have developed a prototype dashboard application that allows users to explore data services in the AOV application. AOV is founded on principles of interoperability, such that agencies and organizations can use the AOV Viewer and web services for their own purposes. In this way, AOV complements other distributed yet interoperable cyber resources and helps science planners, funding agencies, investigators, data specialists, and others to: assess status, identify overlap, fill gaps, optimize sampling design, refine network performance, clarify directions, access data, coordinate logistics, and collaborate to meet Arctic Observing goals.
Measurements of sea ice mass redistribution during ice deformation event in Arctic winter
NASA Astrophysics Data System (ADS)
Itkin, P.; Spreen, G.; King, J.; Rösel, A.; Skourup, H.; Munk Hvidegaard, S.; Wilkinson, J.; Oikkonen, A.; Granskog, M. A.; Gerland, S.
2016-12-01
Sea-ice growth during high winter is governed by ice dynamics. The highest growth rates are found in leads that open under divergent conditions, where exposure to the cold atmosphere promotes thermodynamic growth. Additionally ice thickens dynamically, where convergence causes rafting and ridging. We present a local study of sea-ice growth and mass redistribution between two consecutive airborne measurements, on 19 and 24 April 2015, during the N-ICE2015 expedition in the area north of Svalbard. Between the two overflights an ice deformation event was observed. Airborne laser scanner (ALS) measurements revisited the same sea-ice area of approximately 3x3 km. By identifying the sea surface within the ALS measurements as a reference the sea ice plus snow freeboard was obtained with a spatial resolution of 5 m. By assuming isostatic equilibrium of level floes, the freeboard heights can be converted to ice thickness. The snow depth is estimated from in-situ measurements. Sea ice thickness measurements were made in the same area as the ALS measurements by electromagnetic sounding from a helicopter (HEM), and with a ground-based device (EM31), which allows for cross-validation of the sea-ice thickness estimated from all 3 procedures. Comparison of the ALS snow freeboard distributions between the first and second overflight shows a decrease in the thin ice classes and an increase of the thick ice classes. While there was no observable snowfall and a very low sea-ice growth of older level ice during this period, an autonomous buoy array deployed in the surroundings of the area measured by the ALS shows first divergence followed by convergence associated with shear. To quantify and link the sea ice deformation with the associated sea-ice thickness change and mass redistribution we identify over 100 virtual buoys in the ALS data from both overflights. We triangulate the area between the buoys and calculate the strain rates and freeboard change for each individual triangle. From the freeboard change we calculate the sea ice volume change. Our results show exemplary sea-ice mass redistribution caused by sea ice dynamics during winter conditions in the Arctic, which can be used to estimate sea-ice growth due to deformation processes in a wider region, and ultimately to distinguish between thermodynamic and dynamic ice growth processes.
Levels and trends of contaminants in humans of the Arctic.
Gibson, Jennifer; Adlard, Bryan; Olafsdottir, Kristin; Sandanger, Torkjel Manning; Odland, Jon Øyvind
2016-01-01
The Arctic Monitoring and Assessment Programme (AMAP) is one of the six working groups established under the Arctic Council. AMAP is tasked with monitoring the levels of contaminants present in the Arctic environment and people as well as assessing their effects on a continuous basis, and reporting these results regularly. Most of the presented data have been collected over the last 20 years and are from all eight Arctic countries. Levels of contaminants appear to be declining in some of the monitored Arctic populations, but it is not consistent across the Arctic. Most Arctic populations continue to experience elevated levels of these contaminants compared to other populations monitored globally. There are certain contaminants, such as perfluorinated compounds and polybrominated diphenyl ethers, which are still increasing in Arctic populations. These contaminants require more investigation to find out the predominant and important sources of exposure, and whether they are being transported to the Arctic through long-range transport in the environment.
Levels and trends of contaminants in humans of the Arctic
Gibson, Jennifer; Adlard, Bryan; Olafsdottir, Kristin; Sandanger, Torkjel Manning; Odland, Jon Øyvind
2016-01-01
The Arctic Monitoring and Assessment Programme (AMAP) is one of the six working groups established under the Arctic Council. AMAP is tasked with monitoring the levels of contaminants present in the Arctic environment and people as well as assessing their effects on a continuous basis, and reporting these results regularly. Most of the presented data have been collected over the last 20 years and are from all eight Arctic countries. Levels of contaminants appear to be declining in some of the monitored Arctic populations, but it is not consistent across the Arctic. Most Arctic populations continue to experience elevated levels of these contaminants compared to other populations monitored globally. There are certain contaminants, such as perfluorinated compounds and polybrominated diphenyl ethers, which are still increasing in Arctic populations. These contaminants require more investigation to find out the predominant and important sources of exposure, and whether they are being transported to the Arctic through long-range transport in the environment. PMID:27974136
Record low sea-ice concentration in the central Arctic during summer 2010
NASA Astrophysics Data System (ADS)
Zhao, Jinping; Barber, David; Zhang, Shugang; Yang, Qinghua; Wang, Xiaoyu; Xie, Hongjie
2018-01-01
The Arctic sea-ice extent has shown a declining trend over the past 30 years. Ice coverage reached historic minima in 2007 and again in 2012. This trend has recently been assessed to be unique over at least the last 1450 years. In the summer of 2010, a very low sea-ice concentration (SIC) appeared at high Arctic latitudes—even lower than that of surrounding pack ice at lower latitudes. This striking low ice concentration—referred to here as a record low ice concentration in the central Arctic (CARLIC)—is unique in our analysis period of 2003-15, and has not been previously reported in the literature. The CARLIC was not the result of ice melt, because sea ice was still quite thick based on in-situ ice thickness measurements. Instead, divergent ice drift appears to have been responsible for the CARLIC. A high correlation between SIC and wind stress curl suggests that the sea ice drift during the summer of 2010 responded strongly to the regional wind forcing. The drift trajectories of ice buoys exhibited a transpolar drift in the Atlantic sector and an eastward drift in the Pacific sector, which appeared to benefit the CARLIC in 2010. Under these conditions, more solar energy can penetrate into the open water, increasing melt through increased heat flux to the ocean. We speculate that this divergence of sea ice could occur more often in the coming decades, and impact on hemispheric SIC and feed back to the climate.
Accuracy of short‐term sea ice drift forecasts using a coupled ice‐ocean model
Zhang, Jinlun
2015-01-01
Abstract Arctic sea ice drift forecasts of 6 h–9 days for the summer of 2014 are generated using the Marginal Ice Zone Modeling and Assimilation System (MIZMAS); the model is driven by 6 h atmospheric forecasts from the Climate Forecast System (CFSv2). Forecast ice drift speed is compared to drifting buoys and other observational platforms. Forecast positions are compared with actual positions 24 h–8 days since forecast. Forecast results are further compared to those from the forecasts generated using an ice velocity climatology driven by multiyear integrations of the same model. The results are presented in the context of scheduling the acquisition of high‐resolution images that need to follow buoys or scientific research platforms. RMS errors for ice speed are on the order of 5 km/d for 24–48 h since forecast using the sea ice model compared with 9 km/d using climatology. Predicted buoy position RMS errors are 6.3 km for 24 h and 14 km for 72 h since forecast. Model biases in ice speed and direction can be reduced by adjusting the air drag coefficient and water turning angle, but the adjustments do not affect verification statistics. This suggests that improved atmospheric forecast forcing may further reduce the forecast errors. The model remains skillful for 8 days. Using the forecast model increases the probability of tracking a target drifting in sea ice with a 10 km × 10 km image from 60 to 95% for a 24 h forecast and from 27 to 73% for a 48 h forecast. PMID:27818852
Pan-Arctic observations in GRENE Arctic Climate Change Research Project and its successor
NASA Astrophysics Data System (ADS)
Yamanouchi, Takashi
2016-04-01
We started a Japanese initiative - "Arctic Climate Change Research Project" - within the framework of the Green Network of Excellence (GRENE) Program, funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), in 2011. This Project targeted understanding and forecasting "Rapid Change of the Arctic Climate System and its Global Influences." Four strategic research targets are set by the Ministry: 1. Understanding the mechanism of warming amplification in the Arctic; 2. Understanding the Arctic climate system for global climate and future change; 3. Evaluation of the impacts of Arctic change on the weather and climate in Japan, marine ecosystems and fisheries; 4. Projection of sea ice distribution and Arctic sea routes. Through a network of universities and institutions in Japan, this 5-year Project involves more than 300 scientists from 39 institutions and universities. The National Institute of Polar Research (NIPR) works as the core institute and The Japan Agency for Marine- Earth Science and Technology (JAMSTEC) joins as the supporting institute. There are 7 bottom up research themes approved: the atmosphere, terrestrial ecosystems, cryosphere, greenhouse gases, marine ecology and fisheries, sea ice and Arctic sea routes and climate modeling, among 22 applications. The Project will realize multi-disciplinal study of the Arctic region and connect to the projection of future Arctic and global climatic change by modeling. The project has been running since the beginning of 2011 and in those 5 years pan-Arctic observations have been carried out in many locations, such as Svalbard, Russian Siberia, Alaska, Canada, Greenland and the Arctic Ocean. In particular, 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard, and intensive atmospheric observations were carried out in 2014 and 2015. In addition, the Arctic Ocean cruises by R/V "Mirai" (belonging to JAMSTEC) and other icebreakers belonging to other countries were conducted and mooring buoy observations were also carried out. The data retrieved during these observations was accumulated in the "Arctic Data archive System (ADS)" (https://ads.nipr.ac.jp/) and served with interfaces for analysis. In addition, modeling studies have been promoted from fundamental process model to general circulation model. The successor of the project, ArCS (Arctic Challenge for Sustainability), which lays delivering emphasis on robust scientific information to stakeholders for decision making and solving problems, was started in FY2015. Within this project, a cooperative observation of black carbon are planned to be started at Cape Baranova Station (AARI, Rusia), Severnaya Zemlya, and new activities including emphasizing aerological observations are also planned to be started for contributing to "Year of Polar Prediction (YOPP)" of Polar Prediction Project (PPP/ WMO). It will be desirable to have a future collaboration with IASOA.
Arctic Sea Ice Classification and Mapping for Surface Albedo Parameterization in Sea Ice Modeling
NASA Astrophysics Data System (ADS)
Nghiem, S. V.; Clemente-Colón, P.; Perovich, D. K.; Polashenski, C.; Simpson, W. R.; Rigor, I. G.; Woods, J. E.; Nguyen, D. T.; Neumann, G.
2016-12-01
A regime shift of Arctic sea ice from predominantly perennial sea ice (multi-year ice or MYI) to seasonal sea ice (first-year ice or FYI) has occurred in recent decades. This shift has profoundly altered the proportional composition of different sea ice classes and the surface albedo distribution pertaining to each sea ice class. Such changes impacts physical, chemical, and biological processes in the Arctic atmosphere-ice-ocean system. The drastic changes upset the traditional geophysical representation of surface albedo of the Arctic sea ice cover in current models. A critical science issue is that these profound changes must be rigorously and systematically observed and characterized to enable a transformative re-parameterization of key model inputs, such as ice surface albedo, to ice-ocean-atmosphere climate modeling in order to obtain re-analyses that accurately reproduce Arctic changes and also to improve sea ice and weather forecast models. Addressing this challenge is a strategy identified by the National Research Council study on "Seasonal to Decadal Predictions of Arctic Sea Ice - Challenges and Strategies" to replicate the new Arctic reality. We review results of albedo characteristics associated with different sea ice classes such as FYI and MYI. Then we demonstrate the capability for sea ice classification and mapping using algorithms developed by the Jet Propulsion Laboratory and by the U.S. National Ice Center for use with multi-sourced satellite radar data at L, C, and Ku bands. Results obtained with independent algorithms for different radar frequencies consistently identify sea ice classes and thereby cross-verify the sea ice classification methods. Moreover, field observations obtained from buoy webcams and along an extensive trek across Elson Lagoon and a sector of the Beaufort Sea during the BRomine, Ozone, and Mercury EXperiment (BROMEX) in March 2012 are used to validate satellite products of sea ice classes. This research enables the mapping of Arctic sea ice classes over multiple decades using multiple satellite radar datasets with both coarse resolution for synoptic scales and high resolution for local and regional scales, which are crucial for realistic surface albedo parameterization to significantly advance sea ice forecast and projection models.
Hung, Hayley; Katsoyiannis, Athanasios A; Brorström-Lundén, Eva; Olafsdottir, Kristin; Aas, Wenche; Breivik, Knut; Bohlin-Nizzetto, Pernilla; Sigurdsson, Arni; Hakola, Hannele; Bossi, Rossana; Skov, Henrik; Sverko, Ed; Barresi, Enzo; Fellin, Phil; Wilson, Simon
2016-10-01
Temporal trends of Persistent Organic Pollutants (POPs) measured in Arctic air are essential in understanding long-range transport to remote regions and to evaluate the effectiveness of national and international chemical control initiatives, such as the Stockholm Convention (SC) on POPs. Long-term air monitoring of POPs is conducted under the Arctic Monitoring and Assessment Programme (AMAP) at four Arctic stations: Alert, Canada; Stórhöfði, Iceland; Zeppelin, Svalbard; and Pallas, Finland, since the 1990s using high volume air samplers. Temporal trends observed for POPs in Arctic air are summarized in this study. Most POPs listed for control under the SC, e.g. polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs) and chlordanes, are declining slowly in Arctic air, reflecting the reduction of primary emissions during the last two decades and increasing importance of secondary emissions. Slow declining trends also signifies their persistence and slow degradation under the Arctic environment, such that they are still detectable after being banned for decades in many countries. Some POPs, e.g. hexachlorobenzene (HCB) and lighter PCBs, showed increasing trends at specific locations, which may be attributable to warming in the region and continued primary emissions at source. Polybrominated diphenyl ethers (PBDEs) do not decline in air at Canada's Alert station but are declining in European Arctic air, which may be due to influence of local sources at Alert and the much higher historical usage of PBDEs in North America. Arctic air samples are screened for chemicals of emerging concern to provide information regarding their environmental persistence (P) and long-range transport potential (LRTP), which are important criteria for classification as a POP under SC. The AMAP network provides consistent and comparable air monitoring data of POPs for trend development and acts as a bridge between national monitoring programs and SC's Global Monitoring Plan (GMP). Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Norbye, Bente; Skaalvik, Mari Wolff
2013-01-01
Introduction Decentralized nursing education (DNE) was established at Tromsø University College in 1990 and has since become a part of the bachelor programme in nursing at UiT The Arctic University of Norway. The objective of the study was to investigate whether and to what degree the first DNE programme established in Norway has contributed to recruitment and retention of registered nurses (RNs) in rural healthcare services. Methods The quantitative survey took place in 2012. A questionnaire was distributed to 315 former students who had graduated from the DNE programme from 1994 to 2011. Results The primary finding of this study is that the DNE successfully recruits students from rural areas of Northern Norway. Nearly, 87.5% have their first employment in community healthcare services. They continued to work in the rural areas and 85% still worked as nurses in 2012. The DNE programme has been successful regarding recruitment and retention of RNs to community healthcare services. Fifty-six percent have attended a variety of postgraduate programmes. Conclusion The DNE programme demonstrates itself as a successful study model regarding recruitment and retention of RNs to rural and remote areas. PMID:24286063
Norbye, Bente; Skaalvik, Mari Wolff
2013-01-01
Decentralized nursing education (DNE) was established at Tromsø University College in 1990 and has since become a part of the bachelor programme in nursing at UiT The Arctic University of Norway. The objective of the study was to investigate whether and to what degree the first DNE programme established in Norway has contributed to recruitment and retention of registered nurses (RNs) in rural healthcare services. The quantitative survey took place in 2012. A questionnaire was distributed to 315 former students who had graduated from the DNE programme from 1994 to 2011. The primary finding of this study is that the DNE successfully recruits students from rural areas of Northern Norway. Nearly, 87.5% have their first employment in community healthcare services. They continued to work in the rural areas and 85% still worked as nurses in 2012. The DNE programme has been successful regarding recruitment and retention of RNs to community healthcare services. Fifty-six percent have attended a variety of postgraduate programmes. The DNE programme demonstrates itself as a successful study model regarding recruitment and retention of RNs to rural and remote areas.
Snow depth retrieval from L-band satellite measurements on Arctic and Antarctic sea ice
NASA Astrophysics Data System (ADS)
Maaß, N.; Kaleschke, L.; Wever, N.; Lehning, M.; Nicolaus, M.; Rossmann, H. L.
2017-12-01
The passive microwave mission SMOS provides daily coverage of the polar regions and measures at a low frequency of 1.4 GHz (L-band). SMOS observations have been used to operationally retrieve sea ice thickness up to 1 m and to estimate snow depth in the Arctic for thicker ice. Here, we present how SMOS-retrieved snow depths compare with airborne measurements from NASA's Operation IceBridge mission (OIB) and with AMSR-2 satellite retrievals at higher frequencies, and we show first applications to Antarctic sea ice. In previous studies, SMOS and OIB snow depths showed good agreement on spatial scales from 50 to 1000 km for some days and disagreement for other days. Here, we present a more comprehensive comparison of OIB and SMOS snow depths in the Arctic for 2011 to 2015. We find that the SMOS retrieval works best for cold conditions and depends on auxiliary information on ice surface temperature, here provided by MODIS thermal imagery satellite data. However, comparing SMOS and OIB snow depths is difficult because of the different spatial resolutions (SMOS: 40 km, OIB: 40 m). Spatial variability within the SMOS footprint can lead to different snow conditions as seen from SMOS and OIB. Ideally the comparison is made for uniform conditions: Low lead and open water fraction, low spatial and temporal variability of ice surface temperature, no mixture of multi- and first-year ice. Under these conditions and cold temperatures (surface temperatures below -25°C), correlation coefficients between SMOS and OIB snow depths increase from 0.3 to 0.6. A finding from the comparison with AMSR-2 snow depths is that the SMOS-based maps depend less on the age of the sea ice than the maps derived from higher frequencies. Additionally, we show first results of SMOS snow depths for Antarctic sea ice. SMOS observations are compared to measurements of autonomous snow buoys drifting in the Weddell Sea since 2014. For a better comparability of these point measurements with SMOS data, we use model simulations along these trajectories made with a sea ice version of SNOWPACK, a 1D multi-layer thermodynamic snow model driven by reanalysis data. These simulations are especially helpful for indicating the occurrence of snow-ice-transformation, which cannot be identified in the buoy data and contributes to the measured snow height.
NASA Astrophysics Data System (ADS)
Kontar, Y. Y.
2017-12-01
The Arctic Council is an intergovernmental forum promoting cooperation, coordination and interaction among the Arctic States and indigenous communities on issues of sustainable development and environmental protection in the North. The work of the Council is primarily carried out by six Working Groups: Arctic Contaminants Action Program, Arctic Monitoring and Assessment Programme, Conservation of Arctic Flora and Fauna, Emergency Prevention, Preparedness and Response, Protection of the Arctic Marine Environment, and Sustainable Development Working Group. The Working Groups are composed of researchers and representatives from government agencies. Each Working Group issues numerous scientific assessments and reports on a broad field of subjects, from climate change to emergency response in the Arctic. A key goal of these publications is to contribute to policy-making in the Arctic. Complex networks of information systems and the connections between the diverse elements within the systems have been identified via network analysis. This allowed to distinguish data sources that were used in the composition of the primary publications of the Working Groups. Next step is to implement network analysis to identify and map the relationships between the Working Groups and policy makers in the Arctic.
NASA Astrophysics Data System (ADS)
Kreyscher, Martin; Harder, Markus; Lemke, Peter; Flato, Gregory M.
2000-05-01
A hierarchy of sea ice rheologies is evaluated on the basis of a comprehensive set of observational data. The investigations are part of the Sea Ice Model Intercomparison Project (SIMIP). Four different sea ice rheology schemes are compared: a viscous-plastic rheology, a cavitating-fluid model, a compressible Newtonian fluid, and a simple free drift approach with velocity correction. The same grid, land boundaries, and forcing fields are applied to all models. As verification data, there are (1) ice thickness data from upward looking sonars (ULS), (2) ice concentration data from the passive microwave radiometers SMMR and SSM/I, (3) daily buoy drift data obtained by the International Arctic Buoy Program (IABP), and (4) satellite-derived ice drift fields based on the 85 GHz channel of SSM/I. All models are optimized individually with respect to mean drift speed and daily drift speed statistics. The impact of ice strength on the ice cover is best revealed by the spatial pattern of ice thickness, ice drift on different timescales, daily drift speed statistics, and the drift velocities in Fram Strait. Overall, the viscous-plastic rheology yields the most realistic simulation. In contrast, the results of the very simple free-drift model with velocity correction clearly show large errors in simulated ice drift as well as in ice thicknesses and ice export through Fram Strait compared to observation. The compressible Newtonian fluid cannot prevent excessive ice thickness buildup in the central Arctic and overestimates the internal forces in Fram Strait. Because of the lack of shear strength, the cavitating-fluid model shows marked differences to the statistics of observed ice drift and the observed spatial pattern of ice thickness. Comparison of required computer resources demonstrates that the additional cost for the viscous-plastic sea ice rheology is minor compared with the atmospheric and oceanic model components in global climate simulations.
Sensitivity Analysis of a Lagrangian Sea Ice Model
NASA Astrophysics Data System (ADS)
Rabatel, Matthias; Rampal, Pierre; Bertino, Laurent; Carrassi, Alberto; Jones, Christopher K. R. T.
2017-04-01
Large changes in the Arctic sea ice have been observed in the last decades in terms of the ice thickness, extension and drift. Understanding the mechanisms behind these changes is of paramount importance to enhance our modeling and forecasting capabilities. For 40 years, models have been developed to describe the non-linear dynamical response of the sea ice to a number of external and internal factors. Nevertheless, there still exists large deviations between predictions and observations. There are related to incorrect descriptions of the sea ice response and/or to the uncertainties about the different sources of information: parameters, initial and boundary conditions and external forcing. Data assimilation (DA) methods are used to combine observations with models, and there is nowadays an increasing interest of DA for sea-ice models and observations. We consider here the state-of-the art sea-ice model, neXtSIM te{Rampal2016a}, which is based on a time-varying Lagrangian mesh and makes use of the Elasto-Brittle rheology. Our ultimate goal is designing appropriate DA scheme for such a modelling facility. This contribution reports about the first milestone along this line: a sensitivity analysis in order to quantify forecast error to guide model development and to set basis for further Lagrangian DA methods. Specific features of the sea-ice dynamics in relation to the wind are thus analysed. Virtual buoys are deployed across the Arctic domain and their trajectories of motion are analysed. The simulated trajectories are also compared to real buoys trajectories observed. The model response is also compared with that one from a model version not including internal forcing to highlight the role of the rheology. Conclusions and perspectives for the general DA implementation are also discussed. \\bibitem{Rampal2016a} P. Rampal, S. Bouillon, E. Ólason, and M. Morlighem. ne{X}t{SIM}: a new {L}agrangian sea ice model. The Cryosphere, 10 (3): 1055-1073, 2016.
Changes and variations in the turning angle of Arctic sea ice
NASA Astrophysics Data System (ADS)
Ukita, J.; Honda, M.; Ishizuka, S.
2012-12-01
The motion of sea ice is under influences of forcing from winds and currents and of sea ice properties. In facing rapidly changing Arctic climate we are interested in whether we observe and quantify changes in sea ice conditions reflected in its velocity field. Theoretical consideration on the freedrift model predicts a change in the sea ice turning angle with respect to the direction of forcing wind in association with thinning sea ice thickness. Possible changes in atmospheric and ocean boundary layer conditions may be reflected in the sea ice turning angle through modification of both atmospheric and oceanic Ekman spirals. With these in mind this study examines statistical properties of the turning angle of the Arctic sea ice and compares them with atmospheric/ice/ocean conditions for the period of 1979-2010 on the basis of IABP buoy data. Preliminary results indicate that over this period the turning angle has varying trends depending on different seasons. We found weakly significant (>90% level) changes in the turning angle from August to October with the maximum trend in October. The direction of trends is counter-clockwise with respect to the geostrophic wind direction, which is consistent with the thinning of sea ice. The interannual variability of the turning angle for this peak season of the reduced sea ice cover is not the same as that of the Arctic SIE. However, in recent years the turning angle appears to covary with the surface air temperature, providing supporting evidence for the relationship between the angle and sea ice thickness. In the presentation we will provide results on the relationships between the turning angle and atmospheric and oceanic variables and further discuss their implications.
Summer 2007 and 2008 Arctic Sea Ice Loss in Context: OUTLOOK 2008
NASA Astrophysics Data System (ADS)
Overland, J. E.; Eicken, H.; Wiggins, H. V.
2008-12-01
The Arctic is changing faster than the publication cycle for new information. In response, the SEARCH and DAMOCLES Programs initiated an OUTLOOK 2008 to provide broad-based communication and assessment within the arctic science community on the causes of rapid summer sea ice loss, synthesizing information from Arctic observing networks and model simulations. The question for summer 2008 was whether the previous loss of multi-year sea ice and delay in sea ice formation in autumn 2007 would still allow sufficient winter growth of sea ice thickness to last through the summer 2008, potentially allowing for recovery from the 2007 minimum. The answer is no; summer 2008 was a second sequential year of extremely low minimum sea ice extent. To organize OUTLOOK 2008, respondents were asked in May, June and July to provide a rationale and semi-quantitative assessment of arctic sea ice extent anticipated for September 2008. OUTLOOK 2008 supplemented information maintained by ice centers, universities and other data providers. Using a range of methods, all of the approximately 20 groups responded that summer sea ice would not return to climatological mean conditions, with a median response near the 2007 extent. The range of responses depended on the relative weight given to "initial conditions," e.g., age and thickness of sea ice at the end of spring, versus whether summer winds in 2008 would be as supportive for ice loss as in 2007. Initial conditions turned out to be a primary factor for summer 2008, with implications for continued sea ice loss in future years. OUTLOOK 2008 highlighted aspects of the observation and modeling efforts that require further attention such as interpretation of summer microwave signatures, in situ buoy measurements, and data assimilation in models. We appreciate the contributions from respondents and reviewers who made OUTLOOK 2008 a success.
NASA Astrophysics Data System (ADS)
Yang, Cen; Zhang, Yong-liang
2018-04-01
In this paper we propose a two-buoy wave energy converter composed of a heaving semi-submerged cylindrical buoy, a fixed submerged cylindrical buoy and a power take-off (PTO) system, and investigate the effect of the fixed submerged buoy on the hydrodynamics of the heaving semi-submerged buoy based on the three-dimensional potential theory. And the dynamic response of the semi-submerged buoy and the wave energy conversion efficiency of the converter are analyzed. The difference of the hydrodynamics and the wave energy conversion efficiency of a semi-submerged buoy converter with and without a fixed submerged buoy is discussed. It is revealed that the influence of the fixed submerged buoy on the exciting wave force, the added mass, the radiation damping coefficient and the wave energy conversion efficiency can be significant with a considerable variation, depending on the vertical distance between the heaving semi-submerged buoy and the fixed submerged buoy, the diameter ratio of the fixed submerged buoy to the heaving semi-submerged buoy and the water depth.
Towards development of an operational snow on sea ice product
NASA Astrophysics Data System (ADS)
Stroeve, J.; Liston, G. E.; Barrett, A. P.; Tschudi, M. A.; Stewart, S.
2017-12-01
Sea ice has been visibly changing over the past couple of decades; most notably the annual minimum extent which has shown a distinct downward, and recently accelerating, trend. September mean sea ice extent was over 7×106 km2 in the 1980's, but has averaged less than 5×106 km2 in the last decade. Should this loss continue, there will be wide-ranging impacts on marine ecosystems, coastal communities, prospects for resource extraction and marine activity, and weather conditions in the Arctic and beyond. While changes in the spatial extent of sea ice have been routinely monitored since the 1970s, less is known about how the thickness of the ice cover has changed. While estimates of ice thickness across the Arctic Ocean have become available over the past 20 years based on data from ERS-1/2, Envisat, ICESat, CryoSat-2 satellites and Operation IceBridge aircraft campaigns, the variety of these different measurement approaches, sensor technologies and spatial coverage present formidable challenges. Key among these is that measurement techniques do not measure ice thickness directly - retrievals also require snow depth and density. Towards that end, a sophisticated snow accumulation model is tested in a Lagrangian framework to map daily snow depths across the Arctic sea ice cover using atmospheric reanalysis data as input. Accuracy of the snow accumulation is assessed through comparison with Operation IceBridge data and ice mass balance buoys (IMBs). Impacts on ice thickness retrievals are further discussed.
NASA Technical Reports Server (NTRS)
Zwally, J.
1988-01-01
The ongoing work has established the basis for using multiyear sea ice concentrations from SMMR passive microwave for studies of largescale advection and convergence/divergence of the Arctic sea ice pack. Comparisons were made with numerical model simulations and buoy data showing qualitative agreement on daily to interannual time scales. Analysis of the 7-year SMMR data set shows significant interannual variations in the total area of multiyear ice. The scientific objective is to investigate the dynamics, mass balance, and interannual variability of the Arctic sea ice pack. The research emphasizes the direct application of sea ice parameters derived from passive microwave data (SMMR and SSMI) and collaborative studies using a sea ice dynamics model. The possible causes of observed interannual variations in the multiyear ice area are being examined. The relative effects of variations in the large scale advection and convergence/divergence within the ice pack on a regional and seasonal basis are investigated. The effects of anomolous atmospheric forcings are being examined, including the long-lived effects of synoptic events and monthly variations in the mean geostrophic winds. Estimates to be made will include the amount of new ice production within the ice pack during winter and the amount of ice exported from the pack.
Controllable Buoys and Networked Buoy Systems
NASA Technical Reports Server (NTRS)
Davoudi, Farhooman (Inventor); Davoodi, Faranak (Inventor)
2017-01-01
Buoyant sensor networks are described, comprising floating buoys with sensors and energy harvesting capabilities. The buoys can control their buoyancy and motion, and can organize communication in a distributed fashion. Some buoys may have tethered underwater vehicles with a smart spooling system that allows the vehicles to dive deep underwater while remaining in communication and connection with the buoys.
Chaffin, Justin D; Kane, Douglas D; Stanislawczyk, Keara; Parker, Eric M
2018-06-25
Microcystin (MCY)-producing harmful cyanobacterial blooms (cHABs) are an annual occurrence in Lake Erie, and buoys equipped with water quality sondes have been deployed to help researchers and resource managers track cHABs. The objective of this study was to determine how well water quality sondes attached to buoys measure total algae and cyanobacterial biomass and water turbidity. Water samples were collected next to two data buoys in western Lake Erie (near Gibraltar Island and in the Sandusky subbasin) throughout summers 2015, 2016, and 2017 to determine correlations between buoy sonde data and water sample data. MCY and nutrient concentrations were also measured. Significant (P < 0.001) linear relationships (R 2 > 0.75) occurred between cyanobacteria buoy and water sample data at the Gibraltar buoy, but not at the Sandusky buoy; however, the coefficients at the Gibraltar buoy differed significantly across years. There was a significant correlation between buoy and water sample total chlorophyll data at both buoys, but the coefficient varied considerably between buoys and among years. Total MCY concentrations at the Gibraltar buoy followed similar temporal patterns as buoy and water sample cyanobacterial biomass data, and the ratio of MCY to cyanobacteria-chlorophyll decreased with decreased ambient nitrate concentrations. These results suggest that buoy data are difficult to compare across time and space. Additionally, the inclusion of nitrate concentration data can lead to more robust predictions on the relative toxicity of blooms. Overall, deployed buoys with sondes that are routinely cleaned and calibrated can track relative cyanobacteria abundance and be used as an early warning system for potentially toxic blooms.
Verification and Validation of the Coastal Modeling System. Report 1: Summary Report
2011-12-01
Information Program ( CDIP ) Buoy 036 in a water depth of 40 m (relative to Mean Tide Level, MTL) and from the National Data Buoy Center (NDBC) Buoy...August to 14 September 2005, offshore wave data from a CDIP Buoy 098, the ocean surface wind from NDBC Buoy 51001, and water level data from NOAA station...buoy at 26-m depth was maintained by CDIP (Buoy 430), and data are available online at http://cdip.ucsd.edu. The wind measurements are available
Borrow the Buoys: DOE’s Lidar Buoy Loan Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2017-02-27
After a 19-month deployment off the coast of Virginia, one of PNNL’s research buoys has returned to shore where researchers can analyze the data recorded by the buoy. The data revealed a few major takeaways that will inform future buoy deployments, including the times and conditions when data measurement is most accurate. Through the Department of Energy's Wind Energy Technologies Office's Lidar Buoy Loan Program, managed by PNNL, interested parties can borrow the buoys for year and contribute invaluable data to the wind energy community.
33 CFR 162.255 - Wrangell Narrows, Alaska; use, administration, and navigation.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Channel Buoy 1 TC. East of Tow Channel Buoy 3 TC. West of Tow Channel Buoy 4 TC. East of Colorado Reef... Tow Channel Buoy 5 TC. East of Tow Channel Buoy 7 TC. West of Petersburg: East of Wrangell Narrows...
33 CFR 162.255 - Wrangell Narrows, Alaska; use, administration, and navigation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Channel Buoy 1 TC. East of Tow Channel Buoy 3 TC. West of Tow Channel Buoy 4 TC. East of Colorado Reef... Tow Channel Buoy 5 TC. East of Tow Channel Buoy 7 TC. West of Petersburg: East of Wrangell Narrows...
Seasonality of light transmittance through Arctic sea ice during spring and summe
NASA Astrophysics Data System (ADS)
Nicolaus, M.; Hudson, S. R.; Granskog, M. A.; Pavlov, A.; Taskjelle, T.; Kauko, H.; Katlein, C.; Geland, S.; Perovich, D. K.
2017-12-01
The energy budget of sea ice and the upper ocean during spring, summer, and autumn is strongly affected by the transfer of solar shortwave radiation through sea ice and into the upper ocean. Previous studies highlighted the great importance of the spring-summer transition, when incoming fluxes are highest and even small changes in surface albedo and transmittance have strong impacts on the annual budgets. The timing of melt onset and changes in snow and ice conditions are also crucial for primary productivity and biogeochemical processes. Here we present results from time series measurements of radiation fluxes through seasonal Arctic sea ice, as it may be expected to play a key role in the future Arctic. Our observations were performed during the Norwegian N-ICE drift experiment in 2015 and the Polarstern expedition PS106 in 2017, both studying sea ice north of Svalbard. Autonomous stations were installed to monitor spectral radiation fluxes above and under sea ice. The observation periods cover the spring-summer transition, including snow melt and early melt pond formation. The results show the direct relation of optical properties to under ice algae blooms and their influence on the energy budget. Beyond these results, we will discuss the latest plans and implementation of radiation measurements during the MOSAiC drift in 2019/2020. Then, a full annual cycle of radiation fluxes may be studied from manned and autonomous (buoys) measurements as well as using a remotely operated vehicle (ROV) as measurement platform. These measurements will be performed in direct relation with numerical simulations on different scales.
NASA Astrophysics Data System (ADS)
Kawaguchi, Yusuke; Takeda, Hiroki
2017-04-01
This study focuses on the mixing processes in the vicinity of surface mixed layer (SML) of the Arctic Ocean. Turbulence activity and vertical heat transfer are quantitatively characterized in the Northwind Abyssal Plain, based on the RV Mirai Arctic cruise, during the transition from late summer to early winter 2014. During the cruise, noticeable storm events were observed, which came over the ship's location and contributed to the deepening of the SML. According to the ship-based microstructure observation, within the SML, the strong wind events produced enhanced dissipation rates of turbulent kinetic energy in the order of magnitude of ɛ = 10-6-10-4W kg-1. On thermal variance dissipation rate, χ increases toward the base of SML, reaching O(10-7) K2 s-1, resulting in vertical heat flux of O(10) W m-2. During the occasional energetic mixing events, the near-surface warm water was transferred downward and penetrated through the SML base, creating a cross-pycnocline high-temperature anomaly (CPHTA) at approximately 20-30 m depth. Near CPHTA, the vertical heat flux was anomalously magnified to O(10-100) W m-2. Following the fixed-point observation, in the regions of marginal and thick ice zones, the SML heat content was monitored using an autonomous drifting buoy, UpTempO. During most of the ice-covered period, the ocean-to-ice turbulent heat flux was dominant, rather than the diapycnal heat transfer across the SML bottom interface.
Method for deploying and recovering a wave energy converter
Mundon, Timothy R
2017-05-23
A system for transporting a buoy and a heave plate. The system includes a buoy and a heave plate. An outer surface of the buoy has a first geometrical shape. A surface of the heave plate has a geometrical shape complementary to the first geometrical shape of the buoy. The complementary shapes of the buoy and the heave plate facilitate coupling of the heave plate to the outer surface of the buoy in a transport mode.
33 CFR 66.10-15 - Aids to navigation.
Code of Federal Regulations, 2012 CFR
2012-07-01
... solid colored buoy. A buoy which marks the left side of the channel viewed looking upstream or toward... channel, solid colored buoys shall be established in pairs, one on each side of the navigable channel... that the user should pass between the buoys. (c) On an irregularly defined channel, solid colored buoys...
33 CFR 66.10-15 - Aids to navigation.
Code of Federal Regulations, 2013 CFR
2013-07-01
... solid colored buoy. A buoy which marks the left side of the channel viewed looking upstream or toward... channel, solid colored buoys shall be established in pairs, one on each side of the navigable channel... that the user should pass between the buoys. (c) On an irregularly defined channel, solid colored buoys...
33 CFR 66.10-15 - Aids to navigation.
Code of Federal Regulations, 2014 CFR
2014-07-01
... solid colored buoy. A buoy which marks the left side of the channel viewed looking upstream or toward... channel, solid colored buoys shall be established in pairs, one on each side of the navigable channel... that the user should pass between the buoys. (c) On an irregularly defined channel, solid colored buoys...
MOSAiC - Multidisciplinary drifting Observatory for the Study of Arctic Climate
NASA Astrophysics Data System (ADS)
Shupe, M.; Persson, O. P.; Tjernstrom, M. K.; Dethloff, K.
2012-12-01
The climate in the Arctic is changing faster than in other regions of the Earth, with near surface temperatures rising more than twice as fast as the global average and the perennial sea-ice cover shrinking fast, especially in summer. The Arctic is transitioning towards a new climate regime dominated by first year sea-ice. At the same time, the scientific understanding of processes and feedbacks causing this rapid change is poor and climate modeling in the Arctic remains problematic. Furthermore, the key physical processes and process-interactions in this new emerging Arctic system are likely different from those in the old system that was dominated by multi-year ice. Our understanding of this complex climate system, and ability to improve climate and weather models, is limited by the lack of observations in the extreme and remote central Arctic. Multi-year, detailed and comprehensive measurements, extending from the atmosphere through the sea-ice and into the ocean in the central Arctic Basin are needed to provide process-level understanding of the central Arctic climate system. To address this need, a manned, international drifting station will be installed in the young sea-ice of the western Arctic and follow the evolution of the ice pack as it proceeds through the transpolar drift towards the Fram Strait over the course of 1-2 years. The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), proposed to start in autumn 2017, will be guided by the broad theme: What are the causes and consequences of diminished Arctic sea-ice coverage? To address this theme requires a number of interdisciplinary investigations that target more specific science questions. *How do ongoing changes in the Arctic ice-ocean-atmosphere system drive heat and mass transfers of importance to climate and ecosystems? *What are the processes and feedbacks affecting sea ice cover, atmosphere-ocean stratification and energy budget in the Arctic? *Will an ice reduced Arctic become more biologically productive and what are the consequences of this to other components of the system? *How do the different scales of heterogeneity within the atmosphere ice and ocean interact to impact the linkages or feedbacks within the system? *How do interfacial exchange rates, biology and chemistry couple to regulate the major elemental cycles? MOSAiC will address these multi-disciplinary questions using intensive observations and modeling of processes that transfer energy, mass, and momentum through the atmosphere-ice-ocean system. The centerpiece of the observatory will be an icebreaker-based station to serve as a hub for intensive and comprehensive observations of climatically-significant physical, chemical, and biological processes through the vertical column. To provide important spatial context and horizontal variability, this facility will be the focal point for a constellation of coordinated observations made by drifting buoys, unmanned aerial and underwater vehicles, aircraft, ships, and satellites. These MOSAiC observational activities will serve as a testbed for evaluation and development of models at scales ranging from high-resolution, process models to regional and global climate models. MOSAiC observational and modeling activities will be linked at the outset, such that model needs will be integral in observational design, implementation, and analysis.
Estimation of Arctic Sea Ice Freeboard and Thickness Using CryoSat-2
NASA Astrophysics Data System (ADS)
Lee, S.; Im, J.; Kim, J. W.; Kim, M.; Shin, M.
2014-12-01
Arctic sea ice is one of the significant components of the global climate system as it plays a significant role in driving global ocean circulation. Sea ice extent has constantly declined since 1980s. Arctic sea ice thickness has also been diminishing along with the decreasing sea ice extent. Because extent and thickness, two main characteristics of sea ice, are important indicators of the polar response to on-going climate change. Sea ice thickness has been measured with numerous field techniques such as surface drilling and deploying buoys. These techniques provide sparse and discontinuous data in spatiotemporal domain. Spaceborne radar and laser altimeters can overcome these limitations and have been used to estimate sea ice thickness. Ice Cloud and land Elevation Satellite (ICEsat), a laser altimeter provided data to detect polar area elevation change between 2003 and 2009. CryoSat-2 launched with Synthetic Aperture Radar (SAR)/Interferometric Radar Altimeter (SIRAL) in April 2010 can provide data to estimate time-series of Arctic sea ice thickness. In this study, Arctic sea ice freeboard and thickness between 2011 and 2014 were estimated using CryoSat-2 SAR and SARIn mode data that have sea ice surface height relative to the reference ellipsoid WGS84. In order to estimate sea ice thickness, freeboard, i.e., elevation difference between the top of sea ice surface should be calculated. Freeboard can be estimated through detecting leads. We proposed a novel lead detection approach. CryoSat-2 profiles such as pulse peakiness, backscatter sigma-0, stack standard deviation, skewness and kurtosis were examined to distinguish leads from sea ice. Near-real time cloud-free MODIS images corresponding to CryoSat-2 data measured were used to visually identify leads. Rule-based machine learning approaches such as See5.0 and random forest were used to identify leads. The proposed lead detection approach better distinguished leads from sea ice than the existing approaches. With the freeboard height calculated using the lead detection approach, sea ice thickness was finally estimated using the Archimedes' buoyancy principle. The estimated sea ice freeboard and thickness were validated using ESA airborne Ku-band interferometric radar and Airborne Electromagnetic (AEM) data.
46 CFR 28.115 - Ring life buoys.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 1 2010-10-01 2010-10-01 false Ring life buoys. 28.115 Section 28.115 Shipping COAST... VESSELS Requirements for All Vessels § 28.115 Ring life buoys. (a) Except as provided in paragraph (b) of... life buoy as specified in table 28.115. If the vessel is equipped with a ring life buoy, at least one...
46 CFR 28.115 - Ring life buoys.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 1 2011-10-01 2011-10-01 false Ring life buoys. 28.115 Section 28.115 Shipping COAST... VESSELS Requirements for All Vessels § 28.115 Ring life buoys. (a) Except as provided in paragraph (b) of... life buoy as specified in table 28.115. If the vessel is equipped with a ring life buoy, at least one...
46 CFR 28.115 - Ring life buoys.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 1 2012-10-01 2012-10-01 false Ring life buoys. 28.115 Section 28.115 Shipping COAST... VESSELS Requirements for All Vessels § 28.115 Ring life buoys. (a) Except as provided in paragraph (b) of... life buoy as specified in table 28.115. If the vessel is equipped with a ring life buoy, at least one...
46 CFR 28.115 - Ring life buoys.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 1 2014-10-01 2014-10-01 false Ring life buoys. 28.115 Section 28.115 Shipping COAST... VESSELS Requirements for All Vessels § 28.115 Ring life buoys. (a) Except as provided in paragraph (b) of... life buoy as specified in table 28.115. If the vessel is equipped with a ring life buoy, at least one...
46 CFR 28.115 - Ring life buoys.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 1 2013-10-01 2013-10-01 false Ring life buoys. 28.115 Section 28.115 Shipping COAST... VESSELS Requirements for All Vessels § 28.115 Ring life buoys. (a) Except as provided in paragraph (b) of... life buoy as specified in table 28.115. If the vessel is equipped with a ring life buoy, at least one...
NASA Astrophysics Data System (ADS)
Woods, J. E.; Rigor, I. G.; Valentic, T. A.
2013-12-01
The U.S. Naval Academy Oceanography Department currently has a curriculum based Polar Science Program (USNA PSP). Within the PSP there is an Arctic Buoy Program (ABP) student research component that will include the design, build, testing and deployment of Arctic Observing Platforms. Establishing an active, field-research program in Polar Science will greatly enhance Midshipman education and research, as well as introduce future Naval Officers to the Arctic environment. The Oceanography Department has engaged the USNA Engineering Departments, and in close collaboration with SRI International, developed the USNA Visual Arctic Observing Platforms. The experience gained through Polar field studies and data derived from these platforms will be used to enhance course materials and laboratories and will also be used directly in Midshipman independent research projects. The USNA PSP successfully deployed IceGoat1 (IG1) off the USCGC HEALY in September, 2012. IG1 suffered a malfunction to its solar powered webcam system upon deployment, but is still reporting via ARGOS SATCOM systems basic weather parameters of air temperature, pressure, and position. USNA PSP attempted to build a less robust, but more economical system integrating similar low power observing platforms housed in heavy duty coolers. This allowed for a streamlined process to get a complete system completed in one academic year. IceKids (IK) are similar observing platforms, just not designed to float once the sea ice melts. IK1 was deployed to Antarctica from October 2012 through January 2013 and captured over 11,000 web cam images in near real time of two remote environmental monitoring stations. IK2A and IK3T were built to be deployed at the Naval Academy Ice Experiment in Barrow, AK in March 2013. IK2A was unique in trying to collect and transmit underwater acoustic signals in near real time. The system integrated a passive hydrophone into the already developed low power data transport system. Unfortunately a malfunction occurred post deployment and only a few hours of data was collected while under the ice. IK3T integrated a Vaisala all in one weather station for very accurate Air Temperature, Pressure, and Wind measurements. IK3T is still operating in Barrow, AK as part of the University of Washington's Arctic Observing Experiment (AOX) where very precise temperature measurements are being collected for validation studies.
The IAOOS arctic network project, status and prospect
NASA Astrophysics Data System (ADS)
Pelon, J.; Provost, C.; Sennechael, N.; Calzas, M.; Blouzon, F.; Gascard, J. C.
2015-12-01
It is quite clear that for studying Arctic climate changes, and better understand interacting processes it is essential to follow an integrated approach for observing and modeling the whole Arctic system encompassing the atmosphere, the ocean and sea-ice at once. Due to the difficulties in retrieving key parameters, satellite observations alone are not the right answer. The project we are developing, is an attempt to tackle this challenge by providing and maintaining a new integrated observing network of instrumented buoys over the Arctic Ocean in order to collect simultaneously and in real time information related to the state of the upper Ocean, the lower Atmosphere and the Arctic sea-ice/snow. It is planned to operate several autonomous platforms in a network in the Arctic Ocean for a period of at least 5 years. Each platform is equipped to vertically sense and profile key variables in the ocean, sea-ice and atmosphere using - CTD (conductivity, temperature, depth) vertical profilers sensors collecting ocean temperature and salinity down to 800m depth, - Temperature and heat conductivity in snow and ice from ice-mass-balance systems - Cloud and aerosol lidar profiling of the lower atmosphere - Diffuse and direct solar flux using wide angle radiometer - Meteorological standard parameters at the surface Platforms allow measurements to be transmitted in near real time via Iridium satellites. As they will be drifting, it is planned to replace part of them every year. Major tests were performed deploying progressively fully equipped IAOOS platform at the North Pole in April 2012, 2013 and 2014. These platforms drifted from the North Pole in April to Fram Strait (September, October) providing spring summer and fall field data. Important fieldwork for IAOOS was also taking place within the Norwegian ice camp on board R/V Lance organized by the Norsk Polar Institute from January to June 2015, as part of the Norwegian young ICE (N-ICE 2015) cruise project. These intensive tests were very timely. The first IAOOS array deployment will start in August 2015 from R/V Araon during the Korean cruise organized by the KOPRI in the Canadian Basin and from R/V Polarstern during the German cruise TRANSARC II organized by the Alfred Wegener Institute in the Eurasian Basin. First results obtained in the frame of IAOOS will be presented and discussed.
Space/Time Statistics of Polar Ice Motion
NASA Technical Reports Server (NTRS)
Emery, William J.; Fowler, Charles; Maslanik, James A.
2003-01-01
Ice motions have been computed from passive microwave imagery (SMMR and SSM/I) on a daily basis for both Polar Regions. In the Arctic these daily motions have been merged with daily motions from AVHRR imagery and the Arctic buoy program. In the Antarctic motion only from the AVHRR were available for merging with the passive microwave vectors. Long-term means, monthly means and weekly means have all been computed from the resulting 22-year time series of polar ice motion. Papers are in preparation that present the long term (22 year) means, their variability and show animations of the monthly means over this time period for both Polar Regions. These papers will have links to "enhanced objects" that allow the reader to view the animations as part of the paper. The first paper presents the ice motion results from each of the Polar Regions. The second paper looks only at ice motion in the Arctic in order to develop a time series of ice age in the Arctic. Starting with the first full SMMR year in 1979 we keep track of each individual "ice element" (resolution of the sensor) and track it in the subsequent monthly time series. After a year we "age" each "particle" and we thus can keep track of the age of the ice starting in 1979. We keep track of ice age classes between one and five years and thus we can see the evolution of the ice as it ages after the initial 5-year period. This calculation shows how we are losing the older ice through Fram Strait at a rather alarming rate particularly in the past 15 years. This loss of older ice has resulted in an overall decrease in the thickest, oldest ice, which is now limited to a region just north of the Canadian Archipelago with tongues extending out across the pole towards the Siberian Shelf. This loss of old ice is consistent with the effects of global warming which provides the heat needed to melt, move and disperse this oldest ice through Fram Strait. This is the first step in a progression that may eventually open the Arctic ice pack and lead to an ice-free Arctic Ocean.
46 CFR 117.70 - Ring life buoys.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Ring life buoys. 117.70 Section 117.70 Shipping COAST... Ring Life Buoys and Life Jackets § 117.70 Ring life buoys. (a) A vessel must have one or more ring life... one life buoy of not less than 510 millimeters (20 inches) in diameter; (2) A vessel of more than 7.9...
46 CFR 117.70 - Ring life buoys.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Ring life buoys. 117.70 Section 117.70 Shipping COAST... Ring Life Buoys and Life Jackets § 117.70 Ring life buoys. (a) A vessel must have one or more ring life... one life buoy of not less than 510 millimeters (20 inches) in diameter; (2) A vessel of more than 7.9...
46 CFR 180.70 - Ring life buoys.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 7 2011-10-01 2011-10-01 false Ring life buoys. 180.70 Section 180.70 Shipping COAST...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 180.70 Ring life buoys. (a) A vessel must have one or more ring life buoys as follows: (1) A vessel of not more than 7.9 meters (26 feet) in...
46 CFR 180.70 - Ring life buoys.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 7 2010-10-01 2010-10-01 false Ring life buoys. 180.70 Section 180.70 Shipping COAST...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 180.70 Ring life buoys. (a) A vessel must have one or more ring life buoys as follows: (1) A vessel of not more than 7.9 meters (26 feet) in...
46 CFR 180.70 - Ring life buoys.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 7 2012-10-01 2012-10-01 false Ring life buoys. 180.70 Section 180.70 Shipping COAST...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 180.70 Ring life buoys. (a) A vessel must have one or more ring life buoys as follows: (1) A vessel of not more than 7.9 meters (26 feet) in...
46 CFR 117.70 - Ring life buoys.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Ring life buoys. 117.70 Section 117.70 Shipping COAST... Ring Life Buoys and Life Jackets § 117.70 Ring life buoys. (a) A vessel must have one or more ring life... one life buoy of not less than 510 millimeters (20 inches) in diameter; (2) A vessel of more than 7.9...
46 CFR 117.70 - Ring life buoys.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Ring life buoys. 117.70 Section 117.70 Shipping COAST... Ring Life Buoys and Life Jackets § 117.70 Ring life buoys. (a) A vessel must have one or more ring life... one life buoy of not less than 510 millimeters (20 inches) in diameter; (2) A vessel of more than 7.9...
46 CFR 180.70 - Ring life buoys.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 7 2013-10-01 2013-10-01 false Ring life buoys. 180.70 Section 180.70 Shipping COAST...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 180.70 Ring life buoys. (a) A vessel must have one or more ring life buoys as follows: (1) A vessel of not more than 7.9 meters (26 feet) in...
46 CFR 117.70 - Ring life buoys.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Ring life buoys. 117.70 Section 117.70 Shipping COAST... Ring Life Buoys and Life Jackets § 117.70 Ring life buoys. (a) A vessel must have one or more ring life... one life buoy of not less than 510 millimeters (20 inches) in diameter; (2) A vessel of more than 7.9...
46 CFR 180.70 - Ring life buoys.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 7 2014-10-01 2014-10-01 false Ring life buoys. 180.70 Section 180.70 Shipping COAST...) LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 180.70 Ring life buoys. (a) A vessel must have one or more ring life buoys as follows: (1) A vessel of not more than 7.9 meters (26 feet) in...
NASA Astrophysics Data System (ADS)
Gerland, S.; Rösel, A.; King, J.; Spreen, G.; Divine, D.; Eltoft, T.; Gallet, J. C.; Hudson, S. R.; Itkin, P.; Krumpen, T.; Liston, G. E.; Merkouriadi, I.; Negrel, J.; Nicolaus, M.; Polashenski, C.; Assmy, P.; Barber, D. G.; Duarte, P.; Doulgeris, A. P.; Haas, C.; Hughes, N.; Johansson, M.; Meier, W.; Perovich, D. K.; Provost, C.; Richter-Menge, J.; Skourup, H.; Wagner, P.; Wilkinson, J.; Granskog, M. A.; Steen, H.
2016-12-01
Sea-ice thickness is a crucial parameter to consider when assessing the status of Arctic sea ice, whether for environmental management, monitoring projects, or regional or pan-arctic assessments. Modern satellite remote sensing techniques allow us to monitor ice extent and to estimate sea-ice thickness changes; but accurate quantifications of sea-ice thickness distribution rely on in situ and airborne surveys. From January to June 2015, an international expedition (N-ICE2015) took place in the Arctic Ocean north of Svalbard, with the Norwegian research vessel RV Lance frozen into drifting sea ice. In total, four drifts, with four different floes were made during that time. Sea-ice and snow thickness measurements were conducted on all main ice types present in the region, first year ice, multiyear ice, and young ice. Measurement methods included ground and helicopter based electromagnetic surveys, drillings, hot-wire installations, snow-sonde transects, snow stakes, and ice mass balance and snow buoys. Ice thickness distributions revealed modal thicknesses in spring between 1.6 and 1.7 m, which is lower than reported for the region from comparable studies in 2009 (2.4 m) and 2011 (1.8 m). Knowledge about the ice thickness distribution in a region is crucial to the understanding of climate processes, and also relevant to other disciplines. Sea-ice thickness data collected during N-ICE2015 can also give us insights into how ice and snow thicknesses affect ecosystem processes. In this presentation, we will explore the influence of snow cover and ocean properties on ice thickness, and the role of sea-ice thickness in air-ice-ocean interactions. We will also demonstrate how information about ice thickness aids classification of different sea ice types from SAR satellite remote sensing, which has real-world applications for shipping and ice forecasting, and how sea ice thickness data contributes to climate assessments.
Dynamics of anchor last deployment of submersible buoy system
NASA Astrophysics Data System (ADS)
Zheng, Zhongqiang; Xu, Jianpeng; Huang, Peng; Wang, Lei; Yang, Xiaoguang; Chang, Zongyu
2016-02-01
Submersible buoy systems are widely used for oceanographic research, ocean engineering and coastal defense. Severe sea environment has obvious effects on the dynamics of submersible buoy systems. Huge tension can occur and may cause the snap of cables, especially during the deployment period. This paper studies the deployment dynamics of submersible buoy systems with numerical and experimental methods. By applying the lumped mass approach, a three-dimensional multi-body model of submersible buoy system is developed considering the hydrodynamic force, tension force and impact force between components of submersible buoy system and seabed. Numerical integration method is used to solve the differential equations. The simulation output includes tension force, trajectory, profile and dropping location and impact force of submersible buoys. In addition, the deployment experiment of a simplified submersible buoy model was carried out. The profile and different nodes' velocities of the submersible buoy are obtained. By comparing the results of the two methods, it is found that the numerical model well simulates the actual process and conditions of the experiment. The simulation results agree well with the results of the experiment such as gravity anchor's location and velocities of different nodes of the submersible buoy. The study results will help to understand the conditions of submersible buoy's deployment, operation and recovery, and can be used to guide the design and optimization of the system.
50 CFR 622.31 - Buoy gear identification.
Code of Federal Regulations, 2013 CFR
2013-10-01
... ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF OF MEXICO, AND SOUTH ATLANTIC Reef Fish Resources of the Gulf of Mexico § 622.31 Buoy gear identification. (a) Buoy gear. In the Gulf EEZ, if buoy...
The role of summer surface wind anomalies in the summer Arctic sea ice extent in 2010 and 2011
NASA Astrophysics Data System (ADS)
Ogi, M.; Wallace, J. M.
2012-12-01
Masayo Ogi 1 and John M. Wallace 2 masayo.ogi@jamstec.go.jp wallace@atmos.washington.edu 1Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan 2 Department of Atmospheric Sciences, University of Washington, Seattle, Washington The seasonal evolutions of Arctic sea ice extent (SIE) during the summers of 2010 and 2011 are contrasted with that in 2007. The June SIE in 2010 was lower than that in 2007 and was the lowest for that calendar month in the 32-year (1979-2010) record. The September SIE in 2010 would have set a new record low had it not been for the fact that the ice retreated more slowly during the summer months in that year than it did in 2007. Hence from early July onward, the SIE in 2010 remained at levels above those observed in 2007. The SIE minimum in September 2010 proved to be the third lowest on record, eclipsed by values in both 2007 and 2008. In spring and summer of 2011, the Arctic SIE was as low as it was in 2007, but the SIE in September 2011 did not reach record low levels. The SIE minimum in 2011 proved to be the second lowest on record for the period of 1979-2011. Summertime atmospheric conditions play an important role in controlling the variations in Arctic SIE. In a previous study based on statistical analysis of data collected prior to 2007, we showed that anticyclonic summertime circulation anomalies over the Arctic Ocean during the summer months favor low September SIE. We also found that the record-low ice summer year 2007 was characterized by a strong anticyclonic circulation anomaly, accompanied by an Ekman drift of ice out of the marginal seas toward the central Arctic and eventually toward the Fram Strait, as evidenced by the tracks of drifting buoys. Here we assess the extent to which year-to-year differences in summer winds over the Arctic might have contributed to the differing rates of retreat of ice during the summers of 2007, 2010, and 2011. Our results show that the May-June (MJ) pattern in 2010 is characterized by strong anticyclonic wind anomalies over the Arctic Ocean. The corresponding pattern for July-August-September (JAS) is dominated by a cyclonic gyre centered over the Kara Sea. The corresponding patterns for 2007 are weak in MJ and strongly anticyclonic in JAS. The JJA pattern in 2011 is characterized by anticyclonic wind anomalies over the Arctic directed toward the Fram Strait, whereas the September pattern exhibits wind anomalies directed away from the Fram Strait across the central Arctic Ocean toward the Chukchi Sea. The corresponding patterns for 2007 are strongly anticyclonic and directed toward the Fram Strait in both JJA and September. In the absence of the late season push by the winds, the ice did not retreat quite as far in 2011 as it did in 2007. We have shown evidence that low level winds over the Arctic play an important role in mediating the rate of retreat of sea ice during summer. Anomalous anticyclonic flow over the interior of the Arctic directed toward the Fram Strait favors rapid retreat and vice versa. We have argued that the relative rankings of the September SIE for the years 2007, 2010 and 2011 are largely attributable to the differing rates of decrease of SIE during these summers, which are a consequence of year-to-year differences in the seasonal evolution of summertime winds over the Arctic.
Sustainable Arctic observing network for predicting weather extremes in mid-latitudes
NASA Astrophysics Data System (ADS)
Inoue, J.; Sato, K.; Yamazaki, A.
2016-12-01
Routine atmospheric observations within and over the Arctic Ocean are very expensive and difficult to conduct because of factors such as logistics and the harsh environment. Nevertheless, the great benefit of such observations is their contribution to an improvement of skills of weather predictions over the Arctic and mid-latitudes. The Year of Polar Prediction (YOPP) from mid-2017 to mid-2019 proposed by the World Weather Research Programme - Polar Prediction Project (WWRP-PPP) would be the best opportunity to address the issues. The combination of observations and data assimilation is an effective way to understand the predictability of weather extremes in mid-latitudes. This talk presents the current activities related to PPP based on international special radiosonde observing network in the Arctic, and challenges toward YOPP. Comparing with summer and winter cases, the additional observations over the Arctic during winter were more effective for improving the predicting skills of weather extremes because the impact of the observations would be carried toward the mid-latitudes by the stronger jet stream and its frequent meanderings. During summer, on the other hand, the impact of extra observations was localized over the Arctic region but still important for precise weather forecasts over the Arctic Ocean, contributing to safe navigation along the Northern Sea Route. To consolidate the sustainable Arctic radiosonde observing network, increasing the frequency of observations at Arctic coastal stations, instead of commissioning special observations from ships and ice camps, would be a feasible way. In fact, several existing stations facing the Arctic Ocean have already increased the frequency of observations during winter and/or summer.
Gulf of Maine Research Institute | Welcome
Home GoMOOS Products now on NERACOOS Real-time Buoy Conditions for the Northeast Region-wide Buoy Regional buoy Lat/Lon lines * Inactive buoy Loading... Real Time Data from the Gulf of Maine From the map
Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas.
Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen
2017-01-18
In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas.
Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas
Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen
2017-01-01
In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas. PMID:28106763
Code of Federal Regulations, 2014 CFR
2014-07-01
... define traffic lanes? (a) The buoy's light color that defines the lateral boundaries of a traffic lane must comply with the buoy color schemes in § 62.25 of this chapter. (b) The buoy light may be fixed or... characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation...
Code of Federal Regulations, 2011 CFR
2011-07-01
... define traffic lanes? (a) The buoy's light color that defines the lateral boundaries of a traffic lane must comply with the buoy color schemes in § 62.25 of this chapter. (b) The buoy light may be fixed or... characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation...
Code of Federal Regulations, 2013 CFR
2013-07-01
... define traffic lanes? (a) The buoy's light color that defines the lateral boundaries of a traffic lane must comply with the buoy color schemes in § 62.25 of this chapter. (b) The buoy light may be fixed or... characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation...
Code of Federal Regulations, 2010 CFR
2010-07-01
... define traffic lanes? (a) The buoy's light color that defines the lateral boundaries of a traffic lane must comply with the buoy color schemes in § 62.25 of this chapter. (b) The buoy light may be fixed or... characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation...
Code of Federal Regulations, 2012 CFR
2012-07-01
... define traffic lanes? (a) The buoy's light color that defines the lateral boundaries of a traffic lane must comply with the buoy color schemes in § 62.25 of this chapter. (b) The buoy light may be fixed or... characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation...
An array effect of wave energy farm buoys
NASA Astrophysics Data System (ADS)
Kweon, Hyuck-Min; Lee, Jung-Lyul
2012-12-01
An ocean buoy energy farm is considered for Green energy generation and delivery to small towns along the Korean coast. The present studypresents that the floating buoy-type energy farm appears to be sufficiently feasible fortrapping more energy compared to afixed cylinder duck array. It is also seen from the numerical resultsthat the resonated waves between spaced buoys are further trapped by floating buoy motion.Our numerical study is analyzed by a plane-wave approximation, in which evanescent mode effects are included in a modified mild-slope equation based on the scattering characteristics for a single buoy.
Field tests of acoustic telemetry for a portable coastal observatory
Martini, M.; Butman, B.; Ware, J.; Frye, D.
2006-01-01
Long-term field tests of a low-cost acoustic telemetry system were carried out at two sites in Massachusetts Bay. At each site, an acoustic Doppler current profiler mounted on a bottom tripod was fitted with an acoustic modem to transmit data to a surface buoy; electronics mounted on the buoy relayed these data to shore via radio modem. The mooring at one site (24 m water depth) was custom-designed for the telemetry application, with a custom designed small buoy, a flexible electro-mechanical buoy to mooring joint using a molded chain connection to the buoy, quick-release electro-mechanical couplings, and dual hydrophones suspended 7 m above the bottom. The surface buoy at the second site (33 m water depth) was a U.S. Coast Guard (USCG) channel buoy fitted with telemetry electronics and clamps to hold the hydrophones. The telemetry was tested in several configurations for a period of about four years. The custom-designed buoy and mooring provided nearly error-free data transmission through the acoustic link under a variety of oceanographic conditions for 261 days at the 24 m site. The electro mechanical joint, cables and couplings required minimal servicing and were very reliable, lasting 862 days deployed before needing repairs. The acoustic communication results from the USCG buoy were poor, apparently due to the hard cobble bottom, noise from the all-steel buoy, and failure of the hydrophone assembly. Access to the USCG buoy at sea required ideal weather. ??2006 IEEE.
Evaluating the Effectiveness of DART® Buoy Networks Based on Forecast Accuracy
NASA Astrophysics Data System (ADS)
Percival, Donald B.; Denbo, Donald W.; Gica, Edison; Huang, Paul Y.; Mofjeld, Harold O.; Spillane, Michael C.; Titov, Vasily V.
2018-04-01
A performance measure for a DART® tsunami buoy network has been developed. DART® buoys are used to detect tsunamis, but the full potential of the data they collect is realized through accurate forecasts of inundations caused by the tsunamis. The performance measure assesses how well the network achieves its full potential through a statistical analysis of simulated forecasts of wave amplitudes outside an impact site and a consideration of how much the forecasts are degraded in accuracy when one or more buoys are inoperative. The analysis uses simulated tsunami amplitude time series collected at each buoy from selected source segments in the Short-term Inundation Forecast for Tsunamis database and involves a set for 1000 forecasts for each buoy/segment pair at sites just offshore of selected impact communities. Random error-producing scatter in the time series is induced by uncertainties in the source location, addition of real oceanic noise, and imperfect tidal removal. Comparison with an error-free standard leads to root-mean-square errors (RMSEs) for DART® buoys located near a subduction zone. The RMSEs indicate which buoy provides the best forecast (lowest RMSE) for sections of the zone, under a warning-time constraint for the forecasts of 3 h. The analysis also shows how the forecasts are degraded (larger minimum RMSE among the remaining buoys) when one or more buoys become inoperative. The RMSEs provide a way to assess array augmentation or redesign such as moving buoys to more optimal locations. Examples are shown for buoys off the Aleutian Islands and off the West Coast of South America for impact sites at Hilo HI and along the US West Coast (Crescent City CA and Port San Luis CA, USA). A simple measure (coded green, yellow or red) of the current status of the network's ability to deliver accurate forecasts is proposed to flag the urgency of buoy repair.
Evaluating the Effectiveness of DART® Buoy Networks Based on Forecast Accuracy
NASA Astrophysics Data System (ADS)
Percival, Donald B.; Denbo, Donald W.; Gica, Edison; Huang, Paul Y.; Mofjeld, Harold O.; Spillane, Michael C.; Titov, Vasily V.
2018-03-01
A performance measure for a DART® tsunami buoy network has been developed. DART® buoys are used to detect tsunamis, but the full potential of the data they collect is realized through accurate forecasts of inundations caused by the tsunamis. The performance measure assesses how well the network achieves its full potential through a statistical analysis of simulated forecasts of wave amplitudes outside an impact site and a consideration of how much the forecasts are degraded in accuracy when one or more buoys are inoperative. The analysis uses simulated tsunami amplitude time series collected at each buoy from selected source segments in the Short-term Inundation Forecast for Tsunamis database and involves a set for 1000 forecasts for each buoy/segment pair at sites just offshore of selected impact communities. Random error-producing scatter in the time series is induced by uncertainties in the source location, addition of real oceanic noise, and imperfect tidal removal. Comparison with an error-free standard leads to root-mean-square errors (RMSEs) for DART® buoys located near a subduction zone. The RMSEs indicate which buoy provides the best forecast (lowest RMSE) for sections of the zone, under a warning-time constraint for the forecasts of 3 h. The analysis also shows how the forecasts are degraded (larger minimum RMSE among the remaining buoys) when one or more buoys become inoperative. The RMSEs provide a way to assess array augmentation or redesign such as moving buoys to more optimal locations. Examples are shown for buoys off the Aleutian Islands and off the West Coast of South America for impact sites at Hilo HI and along the US West Coast (Crescent City CA and Port San Luis CA, USA). A simple measure (coded green, yellow or red) of the current status of the network's ability to deliver accurate forecasts is proposed to flag the urgency of buoy repair.
33 CFR 149.320 - What are the requirements for ring life buoys?
Code of Federal Regulations, 2010 CFR
2010-07-01
... length. The light must be mounted on a bracket near the ring life buoy so that, when the ring life buoy is cast loose, the light will be pulled free of the bracket. (c) To each ring life buoy, there must...
NASA Astrophysics Data System (ADS)
Hirsikko, Anne; Brus, David; O'Connor, Ewan J.; Filioglou, Maria; Komppula, Mika; Romakkaniemi, Sami
2017-04-01
In the high and mid latitudes super-cooled liquid water layers are frequently observed on top of clouds. These layers are difficult to forecast with numerical weather prediction models, even though, they have strong influence on atmospheric radiative properties, cloud microphysical properties, and subsequently, precipitation. This work investigates properties of super-cooled liquid water layer topped sub-arctic clouds and precipitation observed with ground-based in-situ (cloud probes) and remote-sensing (a cloud radar, Doppler and multi-wavelength lidars) instrumentation during two-month long Pallas Cloud Experiment (PaCE 2015) in autumn 2015. Analysis is based on standard Cloudnet scheme supplemented with new retrieval products of the specific clouds and their properties. Combination of two scales of observation provides new information on properties of clouds and precipitation in the sub-arctic Pallas region. Current status of results will be presented during the conference. The authors acknowledge financial support by the Academy of Finland (Centre of Excellence Programme, grant no 272041; and ICINA project, grant no 285068), the ACTRIS2 - European Union's Horizon 2020 research and innovation programme under grant agreement No 654109, the KONE foundation, and the EU FP7 project BACCHUS (grant no 603445).
Circumpolar Biodiversity Monitoring Programme: Coastal Expert Workshop meeting summary
Thomson, L.; McLennan, Donald; Anderson, Rebecca D.; Wegeberg, S.; Pettersvik Arvnes, Maria; Sergienko, Liudmila; Behe, Carolina; Moss-Davies, Pitseolak; Fritz, S.; Christensen, T.; Price, C.
2016-01-01
The Coastal Expert Workshop brought together a diverse group of coastal experts with the common goal of developing a biodiversity monitoring program for coastal ecosystems across the circumpolar Arctic. Meeting participants, including northern residents, industry and Non-Governmental Organization (NGO) representatives, scientists, and government regulators from across the circumpolar Arctic, gathered at the Lord Elgin Hotel in Ottawa from March 1 to 3, 2016, to discuss current biodiversity monitoring efforts, understand key issues facing biodiversity in the Arctic coastal areas and suggest monitoring indicators, or Focal Ecosystem Components, for the program. A Traditional Knowledge Holders meeting was held on February 29, 2016 in conjunction with the workshop. The following document provides a summary of the workshop activities and outcomes, and will be followed by a more complete Workshop Report.
NASA Astrophysics Data System (ADS)
Peterson, E. R.; Stanton, T. P.
2016-12-01
Determining ice concentration in the Arctic is necessary to track significant changes in sea ice edge extent. Sea ice concentrations are also needed to interpret data collected by in-situ instruments like buoys, as the amount of ice versus water in a given area determines local solar heating. Ice concentration products are now routinely derived from satellite radiometers including the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E), the Advanced Microwave Scanning Radiometer 2 (AMSR2), the Special Sensor Microwave Imager (SSMI), and the Special Sensor Microwave Imager/Sounder (SSMIS). While these radiometers are viewed as reliable to monitor long-term changes in sea ice extent, their accuracy should be analyzed, and compared to determine which radiometer performs best over smaller features such as melt ponds, and how seasonal conditions affect accuracy. Knowledge of the accuracy of radiometers at high resolution can help future researchers determine which radiometer to use, and be aware of radiometer shortcomings in different ice conditions. This will be especially useful when interpreting data from in-situ instruments which deal with small scale measurements. In order to compare these passive microwave radiometers, selected high spatial resolution one-meter resolution Medea images, archived at the Unites States Geological Survey, are used for ground truth comparison. Sea ice concentrations are derived from these images in an interactive process, although estimates are not perfect ground truth due to exposure of images, shadowing and cloud cover. 68 images are retrieved from the USGS website and compared with 9 useable, collocated SSMI, 33 SSMIS, 36 AMSRE, and 14 AMSR2 ice concentrations in the Arctic Ocean. We analyze and compare the accuracy of radiometer instrumentation in differing ice conditions.
NASA Astrophysics Data System (ADS)
Humphris, S. E.; Conrad, D. S.; Joyce, K.; Whitcomb, L.; Carignan, C.
2006-12-01
The award-winning Dive and Discover web site will provide education and outreach activities during the International Polar Year for an expedition to investigate hydrothermal activity on the Gakkel Ridge using autonomous underwater vehicles. Created in 2000, this web site is targeted mainly at middle-school students (Grades 6-8) and the general public, but is structured to provide multiple layers and levels of information to cover a wide range of educational experience. The backbone of the site is a series of educational modules that address basic science concepts central to marine science and research being conducted in the deep ocean and on the seafloor. The site already contains considerable material on a range of topics pertinent to seafloor exploration, including mid-ocean ridges, hydrothermal vents, and vent biology, as well as Antarctica. For the cruise to the Gakkel Ridge, two new modules relevant to the upcoming Gakkel Ridge cruise are being developed: one on the geography, oceanography and ecosystems of the Arctic Ocean, and another on underwater robotics. During the 2007 cruise, Dive and Discover will provide daily updates on the progress of the cruise through still and video images from the ship and from the seafloor, graphical representations of a wide variety of oceanographic data, explanations about the technology being used, general information about life at sea on an ice breaker conducting marine research, and interviews with the scientists, engineers, and mariners that make oceanographic research possible. In addition, a "Mail Buoy" will allow the general public to communicate directly by email with scientists at sea. Once the cruise is completed, it will remain live on the site so that it can continue to be accessed and used by teachers during any part of the school year.
33 CFR 144.01-25 - Ring life buoys.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Ring life buoys. 144.01-25...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-25 Ring life buoys. (a) Each manned platform must have at least four approved ring life buoys constructed in accordance...
33 CFR 144.01-25 - Ring life buoys.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ring life buoys. 144.01-25...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-25 Ring life buoys. (a) Each manned platform must have at least four approved ring life buoys constructed in accordance...
33 CFR 144.01-25 - Ring life buoys.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Ring life buoys. 144.01-25...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-25 Ring life buoys. (a) Each manned platform must have at least four approved ring life buoys constructed in accordance...
33 CFR 144.01-25 - Ring life buoys.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Ring life buoys. 144.01-25...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-25 Ring life buoys. (a) Each manned platform must have at least four approved ring life buoys constructed in accordance...
33 CFR 144.01-25 - Ring life buoys.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Ring life buoys. 144.01-25...) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-25 Ring life buoys. (a) Each manned platform must have at least four approved ring life buoys constructed in accordance...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mahmood, Rashed; von Salzen, Knut; Flanner, Mark
2016-06-22
This study quantifies black carbon (BC) processes in three global climate models and one chemistry transport model, with focus on the seasonality of BC transport, emissions, wet and dry deposition in the Arctic. In the models, transport of BC to the Arctic from lower latitudes is the major BC source for this region while Arctic emissions are very small. All models simulated a similar annual cycle of BC transport from lower latitudes to the Arctic, with maximum transport occurring in July. Substantial differences were found in simulated BC burdens and vertical distributions, with CanAM (NorESM) producing the strongest (weakest) seasonalmore » cycle. CanAM also has the shortest annual mean residence time for BC in the Arctic followed by SMHI-MATCH, CESM and NorESM. The relative contribution of wet and dry deposition rates in removing BC varies seasonally and is one of the major factors causing seasonal variations in BC burdens in the Arctic. Overall, considerable differences in wet deposition efficiencies in the models exist and are a leading cause of differences in simulated BC burdens. Results from model sensitivity experiments indicate that scavenging of BC in convective clouds acts to substantially increase the overall efficiency of BC wet deposition in the Arctic, which leads to low BC burdens and a more pronounced seasonal cycle compared to simulations without convective BC scavenging. In contrast, the simulated seasonality of BC concentrations in the upper troposphere is only weakly influenced by wet deposition in stratiform (layer) clouds whereas lower tropospheric concentrations are highly sensitive.« less
Circumpolar biodiversity monitoring program (CBMP): Coastal expert workshop meeting report
Anderson, Rebecca D.; McLennan, Donald; Thomson, Laura; Wegeberg, Susse; Pettersvik Arvnes, Maria; Sergienko, Liudmila; Behe, Carolina; Moss-Davies, Pitseolak; Fritz, Stacey; Christensen, Thomas K.; Price, Courtney
2016-01-01
The Coastal Expert Workshop, which took place in Ottawa, Canada from March 1 to 3, 2016, initiated the development of the Arctic Coastal Biodiversity Monitoring Plan (Coastal Plan). Meeting participants, including northern residents, representatives from industry, non-governmental organisations (NGOs), academia, and government regulators and agencies from across the circumpolar Arctic, discussed current biodiversity monitoring efforts, key issues facing biodiversity in Arctic coastal areas, and collectively identified monitoring indicators, or Focal Ecosystem Components (FECs). On February 29, the day before the workshop, a full day was allocated to Traditional Knowledge (TK) holders to meet and elucidate how this important knowledge can be included in the process of building the Coastal Plan and monitoring biodiversity in Arctic coastal areas, along with scientific data and variables. This document provides 1) background information about the Circumpolar Biodiversity Monitoring Programme and the Coastal Expert Monitoring Group, 2) overviews on workshop presentations and breakout sessions, and 3) details regarding outcomes of the workshop that will inform the drafting of the Coastal Plan.
Holtschlag, David J.; Aichele, Steve A.
2002-01-01
Detroit River is a connecting channel on the Great Lakes waterway that joins Lake St. Clair with Lake Erie. The river forms part of the international boundary between the United States and Canada in southeastern Michigan and southern Ontario. Drifting buoys were deployed on Detroit River to help investigate flow characteristics of four selected reaches as part of a source water assessment study of public water intakes. The drifting buoys contained global positioning system (GPS) receivers to help track their movements following their deployment. In some deployments, buoys were released across a transect at approximately uniform intervals to better understand flow patterns. In other deployments, buoys were released in clusters to investigate turbulent dispersion characteristics. Computer animations of buoy movements, which can be viewed through the Internet, are developed to help visualize the results of the buoy deployments.
Forecast skill impact of drifting buoys in the Southern Hemisphere
NASA Technical Reports Server (NTRS)
Kalnay, E.; Atlas, R.; Baker, W.; Halem, M.
1984-01-01
Two analyses are performed to evaluate the effect of drift buoys and the FGGE's special observing system (SOS) on forecasting. The FGGE analysis utilizes all level II-b conventional and special data, and the Nosat analysis employs only surface and conventional upper air data. Twelve five-day forecasts are produced from these data. An additional experiment utilizing the FGGE data base minus buoys data, and the Nosat data base including buoys data is being conducted. The forecasts are compared and synoptic evaluation of the effect of buoys data is described. The results reveal that the FGGE data base with the SOS significantly improves forecasting in the Southern Hemisphere and the loss of buoys data does not have a great effect on forecasting. The Nosat data has less impact on forecasting; however, the addition of buoys data provides an improvement in forecast skills.
46 CFR 131.875 - Lifejackets, immersion suits, and ring buoys.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Lifejackets, immersion suits, and ring buoys. 131.875... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.875 Lifejackets, immersion suits, and ring buoys. (a) Each lifejacket, immersion suit, and ring life buoy must be marked in block capital...
46 CFR 131.875 - Lifejackets, immersion suits, and ring buoys.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Lifejackets, immersion suits, and ring buoys. 131.875... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.875 Lifejackets, immersion suits, and ring buoys. (a) Each lifejacket, immersion suit, and ring life buoy must be marked in block capital...
46 CFR 131.875 - Lifejackets, immersion suits, and ring buoys.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Lifejackets, immersion suits, and ring buoys. 131.875... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.875 Lifejackets, immersion suits, and ring buoys. (a) Each lifejacket, immersion suit, and ring life buoy must be marked in block capital...
46 CFR 131.875 - Lifejackets, immersion suits, and ring buoys.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Lifejackets, immersion suits, and ring buoys. 131.875... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.875 Lifejackets, immersion suits, and ring buoys. (a) Each lifejacket, immersion suit, and ring life buoy must be marked in block capital...
46 CFR 131.875 - Lifejackets, immersion suits, and ring buoys.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Lifejackets, immersion suits, and ring buoys. 131.875... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.875 Lifejackets, immersion suits, and ring buoys. (a) Each lifejacket, immersion suit, and ring life buoy must be marked in block capital...
NASA Astrophysics Data System (ADS)
Quinn, P.
2015-12-01
The Arctic Monitoring and Assessment Programme (AMAP) established an Expert Group on Short-Lived Climate Forcers (SLCFs) in 2009 with the goal of reviewing the state of science surrounding SLCFs in the Arctic and recommending science tasks to improve the state of knowledge and its application to policy-making. In 2011, the result of the Expert Group's work was published in a technical report entitled The Impact of Black Carbon on Arctic Climate (AMAP, 2011). That report focused entirely on black carbon (BC) and co-emitted organic carbon (OC). The SLCFs Expert Group then expanded its scope to include all species co-emitted with BC as well as tropospheric ozone. An assessment report, entitled Black Carbon and Tropospheric Ozone as Arctic Climate Forcers, was published in 2015. The assessment includes summaries of measurement methods and emissions inventories of SLCFs, atmospheric transport of SLCFs to and within the Arctic, modeling methods for estimating the impact of SLCFs on Arctic climate, model-measurement inter-comparisons, trends in concentrations of SLCFs in the Arctic, and a literature review of Arctic radiative forcing and climate response. In addition, three Chemistry Climate Models and five Chemistry Transport Models were used to calculate Arctic burdens of SLCFs and precursors species, radiative forcing, and Arctic temperature response to the forcing. Radiative forcing was calculated for the direct atmospheric effect of BC, BC-snow/ice effect, and cloud indirect effects. Forcing and temperature response associated with different source sectors (Domestic, Energy+Industry+Waste, Transport, Agricultural waste burning, Forest fires, and Flaring) and source regions (United States, Canada, Russia, Nordic Countries, Rest of Europe, East and South Asia, Arctic, mid-latitudes, tropics, southern hemisphere) were calculated. To enable an evaluation of the cost-effectiveness of regional emission mitigation options, the normalized impacts (i.e., impacts per unit emission from each sector and region) were also calculated. Key findings from the 2015 assessment will be presented.
The New Positioning Technology for Sea Recovery Operations in Japan
NASA Astrophysics Data System (ADS)
Shoji, Yasuhiro; Yoshida, Tetsuya; Fuke, Hideyuki; Iijima, Issei; Izutsu, Naoki; Kato, Yoichi; Matsuzaka, Yukihiko; Namiki, Michiyoshi; Sato, Takatoshi; Tamura, Keisuke; Toriumi, Michihiko; Kakehashi, Yuya; Mizuta, Eiichi
2012-07-01
In Japan which has few flat plain and high population density, it is very difficult to drop a balloon safely on to the land. Hence balloons launched from Japan have always been dropped on the sea. In order to recover the balloons and the gondolas floating on the sea surely and rapidly, and to keep the gondolas and ships safe, much efforts and innovations have been made. Ones of the important innovations are positioning buoys. A buoy attached on a balloon gondola floats independently after the splash down, and informs its position to the recovery team. We had developed some types of such buoys; `radio beacon buoy' transmits a pattern of radio signal to navigate the recovery boats to the gondola. Another type of the buoys, `GPS ARGOS buoy,' finds its position with the GPS and sends the information to the balloon base via ARGOS satellite communication network. These technologies had contributed so much to the sea recovery operations however they also had some limitations. Recently, a new positioning buoy with better performance has developed; `Iridium buoy' detects the position with the GPS, and informs it to the balloon base via the Iridium satellite communication network and the internet. The Iridium buoy provides the accurate position surely and immediately with good time resolution. Furthermore the information can be received by very common devices which can receive e-mails. Thanks to the new buoy, the balloon operation team can always know where the gondola is on the sea more precisely, more simultaneously and more easily. That enables the operation team to inform the gondola's location to the authorities concerned as well as the recovery team, which contributes to the safety of both of the gondola and the sea traffics. In this presentation, the Iridium Buoy will be introduced mainly. Also the overview of the present sea recovery operation with the buoy and the past operations will be mentioned
NASA Technical Reports Server (NTRS)
1974-01-01
Information was exchanged between people directly involved with the development, use, and/or potential use of free drifting buoys. Tracking systems and techniques, where methods and accuracy of optical, radio, radar, satellite, and sonic tracking of free-drifting buoys were discussed. Deployment and retrieval covering methods currently used or planned in the deployment and retrieval of free-drifting buoys from boats, ships, helicopters, fixed platforms, and fixed-wing aircraft were reported. Simulation, sensors, and data emphasizing the status of water circulation modeling, and sensors useful on free-drifting buoys, and data display and analysis were described.
NASA Astrophysics Data System (ADS)
Cain, Michelle
2016-04-01
I will discuss my experience co-ordinating a range of communication activities for a multi-university research programme called Methane in the Arctic: Measurements and Modelling. The project included ground- and aircraft-based fieldwork in the European Arctic, as well as computer modelling. Our communication activities included: our own field blog (www.arcticmethane.wordpress.com), which was syndicated to the Scientific American Expeditions blog; writing articles for other blogs with a wider audience than our own; use of twitter; and podcasting our field work. The grand finale to our communications work was a live event at a science festival, in which we took the audience along with us on a recreated research flight, complete with a life-size mock up of a section of our research aircraft. I will discuss my experiences of these forms of communication, and give an evaluation of their successes and failures.
Estimation of Arctic Sea Ice Freeboard and Thickness Using CryoSat-2
NASA Astrophysics Data System (ADS)
Lee, Sanggyun; Im, Jungho; yoon, Hyeonjin; Shin, Minso; Kim, Miae
2014-05-01
Arctic sea ice is one of the significant components of the global climate system as it plays a significant role in driving global ocean circulation, provides a continuous insulating layer at air-sea interface, and reflects a large portion of the incoming solar radiation in Polar Regions. Sea ice extent has constantly declined since 1980s. Its area was the lowest ever recorded on 16 September 2012 since the satellite record began in 1979. Arctic sea ice thickness has also been diminishing along with the decreasing sea ice extent. Because extent and thickness, two main characteristics of sea ice, are important indicators of the polar response to on-going climate change, there has been a great effort to quantify them using various approaches. Sea ice thickness has been measured with numerous field techniques such as surface drilling and deploying buoys. These techniques provide sparse and discontinuous data in spatiotemporal domain. Spaceborne radar and laser altimeters can overcome these limitations and have been used to estimate sea ice thickness. Ice Cloud and land Elevation Satellite (ICEsat), a laser altimeter from National Aeronautics and Space Administration (NASA), provided data to detect polar area elevation change between 2003 and 2009. CryoSat-2 launched with Synthetic Aperture Radar (SAR)/Interferometric Radar Altimeter (SIRAL) on April 2010 can provide data to estimate time-series of Arctic sea ice thickness. In this study, Arctic sea ice freeboard and thickness in 2012 and 2013 were estimated using CryoSat-2 SAR mode data that has sea ice surface height relative to the reference ellipsoid WGS84. In order to estimate sea ice thickness, freeboard height, elevation difference between the top of sea ice surface and leads should be calculated. CryoSat-2 profiles such as pulse peakiness, backscatter sigma-0, number of echoes, and significant wave height were examined to distinguish leads from sea ice. Several near-real time cloud-free MODIS images as CryoSat-2 data were used to identify leads. Rule-based machine learning approaches such as random forest and See5.0 and human-derived decision trees were used to produce rules to identify leads. With the freeboard height calculated from the lead analysis, sea ice thickness was finally estimated using the Archimedes' buoyancy principle with density of sea ice and sea water and the height of freeboard. The results were compared with Arctic sea ice thickness distribution retrieved from CryoSat-2 data by Alfred-Wegener-Institute.
NASA Astrophysics Data System (ADS)
Roiger, A.; Thomas, J. L.; Schlager, H.; Law, K.; Kim, J.; Reiter, A.; Schaefler, A.; Weinzierl, B.; Rose, M.; Raut, J.; Marelle, L.
2013-12-01
Arctic sea ice has decreased dramatically in the past few decades, which has opened the Arctic Ocean to transit shipping and hydrocarbon extraction. These anthropogenic activities are expected to increase emissions of air pollutants and climate forcers (e.g. aerosols, ozone) in the Arctic troposphere significantly in the future. However, large knowledge gaps exist how these emissions influence regional air pollution and Arctic climate. Here we present an overview on the ACCESS (Arctic Climate Change, Economy, and Society, a European Union Seventh Framework Programme project) aircraft campaign, which primarily focused on studying emissions from emerging Arctic pollution sources. During the ACCESS campaign in July 2012, the DLR Falcon was based in Andenes, Norway, and was equipped with a suite of trace gas and aerosol instruments (black carbon, ozone, as well as other trace species). During nine scientific flights, emissions from different ship types (e.g. cargo, passenger, and fishing vessels) and a variety of offshore extraction facilities (e.g. drilling rigs, production and storage platforms) were probed off the Norwegian Coast. The emissions from these increasing pollution sources showed distinct differences in chemical and aerosol composition. To put the emerging local pollution within a broader context, we also measured sulfur-rich emissions originating from industrial activities on the Kola Peninsula and black carbon containing biomass burning plumes imported from Siberian wildfires. We will present an overview on the trace gas and aerosol properties of the different emission sources, and discuss the influence of future local anthropogenic activities on the Arctic air composition by combining measurements with model simulations.
NASA Astrophysics Data System (ADS)
Ortiz, M.; Pinales, J. C.; Graber, H. C.; Wilkinson, J.; Lund, B.
2016-02-01
Melt ponds on sea ice play a significant and complex role on the thermodynamics in the Marginal Ice Zone (MIZ). Ponding reduces the sea ice's ability to reflect sunlight, and in consequence, exacerbates the albedo positive feedback cycle. In order to understand how melt ponds work and their effect on the heat uptake of sea ice, we must quantify ponds through their seasonal evolution first. A semi-supervised neural network three-class learning scheme using a gradient descent with momentum and adaptive learning rate backpropagation function is applied to classify melt ponds/melt areas in the Beaufort Sea region. The network uses high resolution panchromatic satellite images from the MEDEA program, which are collocated with autonomous platform arrays from the Marginal Ice Zone Program, including ice mass-balance buoys, arctic weather stations and wave buoys. The goal of the study is to capture the spatial variation of melt onset and freeze-up of the ponds within the MIZ, and gather ponding statistics such as size and concentration. The innovation of this work comes from training the neural network as the melt ponds evolve over time; making the machine learning algorithm time-dependent, which has not been previously done. We will achieve this by analyzing the image histograms through quantification of the minima and maxima intensity changes as well as linking textural variation information of the imagery. We will compare the evolution of the melt ponds against several different array sites on the sea ice to explore if there are spatial differences among the separated platforms in the MIZ.
NASA Astrophysics Data System (ADS)
Chetty, S.; Field, L. A.
2013-12-01
The Arctic ocean's continuing decrease of summer-time ice is related to rapidly diminishing multi-year ice due to the effects of climate change. Ice911 Research aims to develop environmentally respectful materials that when deployed will increase the albedo, enhancing the formation and/preservation of multi-year ice. Small scale deployments using various materials have been done in Canada, California's Sierra Nevada Mountains and a pond in Minnesota to test the albedo performance and environmental characteristics of these materials. SWIMS is a sophisticated autonomous sensor system being developed to measure the albedo, weather, water temperature and other environmental parameters. The system (SWIMS) employs low cost, high accuracy/precision sensors, high resolution cameras, and an extreme environment command and data handling computer system using satellite and terrestrial wireless communication. The entire system is solar powered with redundant battery backup on a floating buoy platform engineered for low temperature (-40C) and high wind conditions. The system also incorporates tilt sensors, sonar based ice thickness sensors and a weather station. To keep the costs low, each SWIMS unit measures incoming and reflected radiation from the four quadrants around the buoy. This allows data from four sets of sensors, cameras, weather station, water temperature probe to be collected and transmitted by a single on-board solar powered computer. This presentation covers the technical, logistical and cost challenges in designing, developing and deploying these stations in remote, extreme environments. Image captured by camera #3 of setting sun on the SWIMS station One of the images captured by SWIMS Camera #4
Skaalvik, Mari Wolff; Gaski, Margrete; Norbye, Bente
2014-01-01
Ensuring a sufficient nursing workforce, with respect to both number and relevant professional competencies, is crucial in rural Arctic regions in Norway. This study examines the continuing education (CE) of nurses who graduated from a decentralized nursing programme between 1994 and 2011. This study aims to measure the extent to which the decentralized nursing education (DNE) in question has served as a basis for CE that is adapted to current and future community health care service needs in rural Arctic regions in northern Norway. More specifically, the study aims to investigate the frequency and scope of CE courses among the graduates of a DNE, the choice of study model and the degree of employment with respect to the relevant CE. This study is a quantitative survey providing descriptive statistics. The primary finding in this study is that 56% of the participants had engaged in CE and that they were employed in positions related to their education. The majority of students with decentralized bachelor's degrees engaged in CE that was part time and/or decentralized. More than half of the population in this study had completed CE despite no mandatory obligation in order to maintain licensure. Furthermore, 31% of the participants had completed more than one CE programme. The findings show that the participants preferred CE organized as part time and or decentralized studies.
Buoy monitors ocean acidification
NASA Astrophysics Data System (ADS)
Zielinski, Sarah
2007-06-01
A new Gulf of Alaska buoy installed on 7 June is the first to provide data that will help scientists study ocean acidification caused by the absorption of atmospheric carbon dioxide. Sensors attached to the buoy are measuring key climate indicators in the atmosphere and ocean, including surface acidity and the air-sea exchange of carbon dioxide. The buoy was installed in collaboration with the Line P program, which has provided decades of continuous measurements from a series of oceanographic stations along line P which extends from the mouth of the Juan de Fuca Strait south of Vancouver Island to Pacific Ocean Station Papa, where the new buoy was installed.The buoy is part of a project conducted by scientists from NOAAs Pacific Marine Environmental Laboratory; the University of Washington, Seattle; Fisheries and Oceans Canada; and the Institute of Ocean Sciences in Sydney, British Columbia.
A Scientific Synthesis and Assessment of the Arctic Carbon Cycle
NASA Astrophysics Data System (ADS)
Hayes, Daniel J.; Guo, Laodong; McGuire, A. David
2007-06-01
The Arctic Monitoring and Assessment Programme (AMAP), along with the Climate and Cryosphere (CliC) Project and the International Arctic Science Committee (IASC), sponsored the Arctic Carbon Cycle Assessment Workshop, at the Red Lion Hotel in Seattle, Wash., between 27 February and 1 March 2007. The workshop was held in a general effort toward the scientific synthesis and assessment of the Arctic system carbon cycle, as well as to generate feedback on the working draft of an assessment document. The initial assessment was prepared by the Arctic carbon cycle assessment writing team, which is led by A. David McGuire (University of Alaska Fairbanks) and includes Leif Anderson (Goteborg University, Sweden), Torben Christensen (Lund University, Sweden), Scott Dallimore (Natural Resources Canada), Laodong Guo (University of Southern Mississippi), Martin Heimann (Max Planck Institute, Germany), Robie MacDonald (Department of Fisheries and Oceans, Canada), and Nigel Roulet (McGill University, Canada). The workshop brought together leading researchers in the fields of terrestrial, marine, and atmospheric science to report on and discuss the current state of knowledge on contemporary carbon stocks and fluxes in the Artie and their potential responses to a changing climate. The workshop was attended by 35 scientists representing institutions from 10 countries in addition to two representatives of the sponsor agencies (John Calder for AMAP and Diane Verseghy for CliC).
33 CFR 162.117 - St. Marys River, Sault Ste. Marie, Michigan.
Code of Federal Regulations, 2011 CFR
2011-07-01
...”—downbound traffic only; (ii) Pipe Island Course from Sweets Point to Watson Reefs Light-downbound traffic... Island Passage to the east of Pipe Island Shoal and north of Pipe Island Twins from Watson Reefs Light to...: (i) Johnson Point from Buoy “18” to Buoy “22”; (ii) Mirre Point from Buoy “26” to Buoy “28”; or (iii...
33 CFR 162.117 - St. Marys River, Sault Ste. Marie, Michigan.
Code of Federal Regulations, 2013 CFR
2013-07-01
...”—downbound traffic only; (ii) Pipe Island Course from Sweets Point to Watson Reefs Light-downbound traffic... Island Passage to the east of Pipe Island Shoal and north of Pipe Island Twins from Watson Reefs Light to...: (i) Johnson Point from Buoy “18” to Buoy “22”; (ii) Mirre Point from Buoy “26” to Buoy “28”; or (iii...
33 CFR 162.117 - St. Marys River, Sault Ste. Marie, Michigan.
Code of Federal Regulations, 2014 CFR
2014-07-01
...”—downbound traffic only; (ii) Pipe Island Course from Sweets Point to Watson Reefs Light-downbound traffic... Island Passage to the east of Pipe Island Shoal and north of Pipe Island Twins from Watson Reefs Light to...: (i) Johnson Point from Buoy “18” to Buoy “22”; (ii) Mirre Point from Buoy “26” to Buoy “28”; or (iii...
33 CFR 162.117 - St. Marys River, Sault Ste. Marie, Michigan.
Code of Federal Regulations, 2012 CFR
2012-07-01
...”—downbound traffic only; (ii) Pipe Island Course from Sweets Point to Watson Reefs Light-downbound traffic... Island Passage to the east of Pipe Island Shoal and north of Pipe Island Twins from Watson Reefs Light to...: (i) Johnson Point from Buoy “18” to Buoy “22”; (ii) Mirre Point from Buoy “26” to Buoy “28”; or (iii...
Department of Energy WindSentinel Loan Program Description
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shaw, William J.; Sturges, Mark H.
The U.S. Department of Energy (DOE) currently owns two AXYS WindSentinel buoys that collect a comprehensive set of meteorological and oceanographic data to support resource characterization for wind energy offshore. The two buoys were delivered to DOE’s Pacific Northwest National Laboratory (PNNL) in September, 2014. After acceptance testing and initial performance testing and evaluation at PNNL’s Marine Sciences Laboratory in Sequim, Washington, the buoys have been deployed off the U.S. East Coast. One buoy was deployed approximately 42 km east of Virginia Beach, Virginia from December, 2014 through June, 2016. The second buoy was deployed approximately 5 km off Atlanticmore » City, New Jersey in November, 2015. Data from the buoys are available to the public. Interested parties can create an account and log in to http://offshoreweb.pnnl.gov. In response to a number of inquiries and unsolicited proposals, DOE’s Wind Energy Technologies Office is implementing a program, to be managed by PNNL, to lend the buoys to qualified parties for the purpose of acquiring wind resource characterization data in areas of interest for offshore wind energy development. This document describes the buoys, the scope of the loans, the process of how borrowers will be selected, and the schedule for implementation of this program, including completing current deployments.« less
Childs, Jonathan R.; Triezenberg, Peter J.; Danforth, William W.
2012-01-01
In September 2008, the U.S. Geological Survey (USGS), in cooperation with Natural Resources Canada, Geological Survey of Canada (GSC), conducted bathymetric and geophysical surveys in the Arctic Beaufort Sea aboard the U.S. Coast Guard cutter USCGC Healy. The principal objective of this mission to the high Arctic was to acquire data in support of delineation of the outer limits of the U.S. and Canadian Extended Continental Shelf (ECS) in the Arctic Ocean in accordance with the provisions of Article 76 of the Law of the Sea Convention. The Healy was accompanied by the Canadian Coast Guard icebreaker Louis S. St- Laurent. The science parties on the two vessels consisted principally of staff from the USGS (Healy), and the GSC and the Canadian Hydrographic Service (Louis). The crew included marine mammal and Native-community observers, ice observers, and biologists conducting research of opportunity in the Arctic Ocean. The joint survey proved an unqualified success. The Healy collected 5,528 km of swath (multibeam) bathymetry (38,806 km2) and CHIRP subbottom profile data, with accompanying marine gravity measurements. The Louis acquired 2,817 km of multichannel seismic (airgun) deep-penetration reflection-profile data along 12 continuous lines, as well as 35 sonobuoy refraction stations and accompanying single-beam bathymetry. The coordinated efforts of the two vessels resulted in seismic-reflection profile data of much higher quality and continuity than if the data had been acquired with a single vessel alone. Equipment failure rate of the seismic equipment gear aboard the Louis was greatly improved with the advantage of having a leading icebreaker. When ice conditions proved too severe to deploy the seismic system, the Louis led the Healy, resulting in much improved quality of the swath bathymetry and CHIRP sub-bottom data in comparison with data collected by the Healy in the lead or working alone. Ancillary science objectives, including ice observations, deployment of ice-monitoring buoys and water-column sampling for biologic (phytoplankton) studies, were also successfully accomplished.
Loran-Based Buoy Position Auditing Systems - Analytical Evaluation
DOT National Transportation Integrated Search
1980-02-01
An analytic evaluation and comparison of the following candidate Buoy Position Auditing System (BPAS) configurations is presented in this report: transmission of digital Time Difference (TD) data from a Loran-C receiver on the buoy, retransmission of...
An atlas of GEOS-3 radar altimeter data for data buoy comparison studies
NASA Technical Reports Server (NTRS)
Stanley, H. R.; Taylor, R. L.
1978-01-01
An atlas is compiled to identify times and dates when GEOS-3 altimeter data was taken in the vicinity of data buoys. The time period covered is from GEOS launch to April 9, 1978. Two buffer areas are considered for each of the various buoy locations to determine the simultaneity of GEOS and buoy data. The two buffer areas are ? or - 0.25 degrees and ? or - 1 degree.
NASA Technical Reports Server (NTRS)
Usry, J. W.; Wallace, J. W.
1972-01-01
The buoys were deployed on the Continental Shelf east of the Chesapeake Light and were tracked by the French EOLE satellite. Two buoys drifted for 11 days during the first mission and four buoys drifted for 14 days during the second mission. Trajectory and water temperature data are presented in tabular and graphical from with a discussion of the accuracy.
Buoy Technology survey USCG Buoy Development Review
1990-10-01
by the United States Coadst Guard, IALA Conference, No. 3.1.5, Tokyo, 1980 . 3P.H. Glage, Design, Procurement and Testing of Plastic Fast Water Buoys on...may include published reports, unpublished reports, and USCG files. 23 PROJECT SUMMARY NO. 1 ARTICULATED BEACON DEVELOPMENT DATES: 1980 to Present...PROJECT DATE’%: 1980 to Present OBJECTIVE: The purpose of this project is to design a special buoy for use in exposed offshore locations where high
A Wave Power Device with Pendulum Based on Ocean Monitoring Buoy
NASA Astrophysics Data System (ADS)
Chai, Hui; Guan, Wanchun; Wan, Xiaozheng; Li, Xuanqun; Zhao, Qiang; Liu, Shixuan
2018-01-01
The ocean monitoring buoy usually exploits solar energy for power supply. In order to improve power supply capacity, this paper proposes a wave power device according to the structure and moving character of buoy. The wave power device composes of pendulum mechanism that converts wave energy into mechanical energy and energy storage mechanism where the mechanical energy is transferred quantitatively to generator. The hydrodynamic equation for the motion of buoy system with generator devise is established based on the potential flow theory, and then the characteristics of pendulum motion and energy conversion properties are analysed. The results of this research show that the proposed wave power devise is able to efficiently and periodically convert wave energy into power, and increasing the stiffness of energy storage spring is benefit for enhancing the power supply capacity of the buoy. This study provides a theory reference for the development of technology on wave power generator for ocean monitoring buoy.
NASA Technical Reports Server (NTRS)
Oberholtzer, David; Donelan, Mark
1996-01-01
This is a guide to the data that was collected during the Surface Wave Dynamics Experiment (SWADE) carried out from October 1990 through March 1991. The area studied was the Mid-Atlantic bight. Buoys collected data continuously during this time. Included are three 3-meter discus buoys the National Data Buoy Center (NDBC) set in the area for this project, they then later added a fourth 3-meter discus and an experimental coastal buoy. Data from all of the NDBC buoys and stations from New England to Florida have been included in the data set; in addition, several other buoys monitored meteorological and ocean conditions for parts of the experiment. Several times during the project, there were intensive data collection periods. During the third of these, there were 7 aircraft and a ship collecting data. Maps of each mission from the platforms that have shared their data are included. The anonymous FTP site that has been established to make this data public is described.
Advanced Approach of Multiagent Based Buoy Communication
Gricius, Gediminas; Drungilas, Darius; Dzemydiene, Dale
2015-01-01
Usually, a hydrometeorological information system is faced with great data flows, but the data levels are often excessive, depending on the observed region of the water. The paper presents advanced buoy communication technologies based on multiagent interaction and data exchange between several monitoring system nodes. The proposed management of buoy communication is based on a clustering algorithm, which enables the performance of the hydrometeorological information system to be enhanced. The experiment is based on the design and analysis of the inexpensive but reliable Baltic Sea autonomous monitoring network (buoys), which would be able to continuously monitor and collect temperature, waviness, and other required data. The proposed approach of multiagent based buoy communication enables all the data from the costal-based station to be monitored with limited transition speed by setting different tasks for the agent-based buoy system according to the clustering information. PMID:26345197
Southeast Oahu Coastal Hydrodynamic Modeling with ADCIRC and STWAVE
2008-07-01
19 Figure 16. CDIP buoy locations...20 Figure 17. Wave height versus wave direction percent occurrence rose for CDIP Buoy 098 – Mokapu Point, HI...wave height versus wave period for CDIP Buoy 098 – Mokapu Point, HI
GNSS Buoy Array in the Ocean for Natural Hazard Mitigation
NASA Astrophysics Data System (ADS)
Kato, T.; Terada, Y.; Yamamoto, S. I.; Iwakiri, N.; Toyoshima, M.; Koshikawa, N.; Motohashi, O.; Hashimoto, G.; Wada, A.
2015-12-01
The GNSS buoy system for tsunami early warning has been developed in Japan. The system has been implemented as a national wave monitoring system and its record was used to update the tsunami warning at the 3.11 Tohoku-oki earthquake. The lessons learned in this experience was that the buoys are placed only less than 20km from the coast, which was not far enough for effective evacuation of people. We thus tried to improve the system for putting the buoy much farther from the coast. First, we tried to implement, different from current baseline mode RTK-GPS, a real-time PPP analysis strategy for positioning. In addition, we tried to use a two-way satellite data transmission in contrast with current surface radio system. We have made a series of experiments for this purpose in 2013 and 2014. A buoy of about 40km south of Shikoku, southwest Japan, was used for this purpose. GEONET data were used to obtain precise orbits and clocks of satellites. Then, the information was transferred to the GNSS buoy using LEX signal of QZSS satellite system. The received information on the buoy were used for real-time PPP analysis for every second. The obtained buoy position was then transmitted to the ground base, through an engineering test satellite, ETS-VIII. The received data was then disseminated to public through the internet. Both filtered short-term and long-term waves, were separately shown on the webpage. The success of these experiments indicates that the GNSS buoy can be placed at least more than 1,500 km from the ground based tracking network. Given this success, we would now be able to deploy a new GNSS buoy array system in the wide ocean. An array in the ocean can be used for ionospheric and atmospheric research in the same region as well as tsunami or ocean bottom crustal deformation monitoring through an application to the GNSS-acoustic system. We are now designing a regional GNSS buoy array in the western Pacific as a synthetic natural hazard mitigation system.
NASA Astrophysics Data System (ADS)
Roiger, Anke; Thomas, Jennie L.; Schlager, Hans; Law, Kathy; Kim, Jin; Reiter, Anja; Schäfler, Andreas; Weinzierl, Bernadett; Rose, Maximilian; Raut, Jean-Christophe; Marelle, Louis
2014-05-01
Arctic change has opened the region to new industrial activities, most notably transit shipping and resource extraction. The impacts that Arctic industrialization will have on pollutants and Arctic climate are not well understood. In order to understand how shipping and offshore oil/gas extraction impact on Arctic tropospheric chemistry and composition, we conducted the ACCESS (Arctic Climate Change, Economy, and Society, a European Union Seventh Framework Programme project) aircraft campaign. The campaign was conducted in July 2012 using the DLR Falcon research aircraft, based in Andenes, Norway. The Falcon was equipped with a suite of trace gas and aerosol instruments (black carbon, ozone, as well as other trace species) to characterize these emissions and their atmospheric chemistry. The Falcon performed nine scientific flights to study emissions from different ships (e.g. cargo, passenger, and fishing vessels) and a variety of offshore extraction facilities (e.g. drilling rigs, production and storage platforms) off the Norwegian Coast. Distinct differences in chemical and aerosol composition were found in emissions from these increasing pollution sources. We also studied the composition of biomass burning plumes imported from Siberian wildfires to put the emerging local pollution within a broader context. In addition to our measurements, we used a regional chemical transport model to study the influence of emerging pollution sources on gas and aerosol concentrations in the region. We will present an overview on the measured trace gas and aerosol properties of the different emission sources and discuss the impact of future local anthropogenic activities on the Arctic air composition by combining measurements with model simulations.
Tsunami Detection Systems for International Requirements
NASA Astrophysics Data System (ADS)
Lawson, R. A.
2007-12-01
Results are presented regarding the first commercially available, fully operational, tsunami detection system to have passed stringent U.S. government testing requirements and to have successfully demonstrated its ability to detect an actual tsunami at sea. Spurred by the devastation of the December 26, 2004, Indian Ocean tsunami that killed more than 230,000 people, the private sector actively supported the Intergovernmental Oceanographic Commission's (IOC"s) efforts to develop a tsunami warning system and mitigation plan for the Indian Ocean region. As each country in the region developed its requirements, SAIC recognized that many of these underdeveloped countries would need significant technical assistance to fully execute their plans. With the original focus on data fusion, consequence assessment tools, and warning center architecture, it was quickly realized that the cornerstone of any tsunami warning system would be reliable tsunami detection buoys that could meet very stringent operational standards. Our goal was to leverage extensive experience in underwater surveillance and oceanographic sensing to produce an enhanced and reliable deep water sensor that could meet emerging international requirements. Like the NOAA Deep-ocean Assessment and Recording of Tsunamis (DART TM ) buoy, the SAIC Tsunami Buoy (STB) system consists of three subsystems: a surfaccommunications buoy subsystem, a bottom pressure recorder subsystem, and a buoy mooring subsystem. With the operational success that DART has demonstrated, SAIC decided to build and test to the same high standards. The tsunami detection buoy system measures small changes in the depth of the deep ocean caused by tsunami waves as they propagate past the sensor. This is accomplished by using an extremely sensitive bottom pressure sensor/recorder to measure very small changes in pressure as the waves move past the buoy system. The bottom pressure recorder component includes a processor with algorithms that recognize these characteristics, and then immediately alerts a tsunami warning center through the communications buoy when the processor senses one of these waves. In addition to the tsunami detection buoy system, an end-to-end tsunami warning system was developed that builds upon the country's existing disaster warning infrastructure. This warning system includes 1) components that receive, process, and analyze buoy, seismic and tide gauge data; 2) predictive tools and a consequence assessment tool set to provide decision support; 3) operation center design and implementation; and 4) tsunami buoy operations and maintenance support. The first buoy was deployed Oct. 25, 2006, approximately 200 nautical miles west of San Diego in 3,800 meters of water. Just three weeks later, it was put to the test during an actual tsunami event. On Nov. 15, 2006, an 8.3 magnitude earthquake rocked the Kuril Islands, located between Japan and the Kamchatka Peninsula of Russia. That quake generated a small tsunami. Waves from the tsunami propagated approximately 4,000 nautical miles across the Pacific Ocean in about nine hours-- a speed of about 445 nautical miles per hour when this commercial buoy first detected them. Throughout that event, the tsunami buoy system showed excellent correlation with data collected by a NOAA DART buoy located 28 nautical miles north of it. Subsequent analysis revealed that the STB matched DART operational capabilities and performed flawlessly. The buoy proved its capabilities again on Jan. 13, 2007, when an 8.1 magnitude earthquake occurred in the same region, and the STB detected the seismic event. As a result of the successes of this entire project, SAIC recently applied for and received a license from NOAA to build DART systems.
Wave-Current Interaction in Coastal Inlets and River Mouths
2014-09-30
the Astoria Canyon buoy operated by the Coastal Data Information Program ( CDIP , buoy # 46248). Three-dimensional current fields and bathymetry were...bar show considerable differences. The SWAN model uses observations from CDIP buoy # 46248 as boundary condition; three- dimensional current data and
Previsic, Mirko; Karthikeyan, Anantha; Lewis, Tony; McCarthy, John
2017-07-26
Capex numbers are in $/kW, Opex numbers in $/kW-yr. Cost Estimates provided herein are based on concept design and basic engineering data and have high levels of uncertainties embedded. This reference economic scenario was done for a very large device version of the OE Buoy technology, which is not presently on Ocean Energy's technology development pathway but will be considered in future business plan development. The DOE reference site condition is considered a low power-density site, compared with many of the planned initial deployment locations for the OE Buoy. Many of the sites considered for the initial commercial deployment of the OE buoy feature much higher wave power densities and shorter period waves. Both of these characteristics will improve the OE buoy's commercial viability.
Wave-Current Interaction in Coastal Inlets and River Mouths
2013-09-30
Astoria Canyon buoy operated by the Coastal Data Information Program ( CDIP , buoy # 46248). Three-dimensional current fields and bathymetry were...The model was initialized with wave measurements from CDIP buoy 46248 located at the tip of the Astoria Canyon, and uses modeled current fields
Nilsson, Lena Maria; Berner, James; Dudarev, Alexey A; Mulvad, Gert; Odland, Jon Øyvind; Parkinson, Alan; Rautio, Arja; Tikhonov, Constantine; Evengård, Birgitta
2013-01-01
In August 2012, a literature search with the aim of describing indicators on food and water security in an Arctic health context was initialized in collaboration between the Arctic Human Health Expert Group, SDWG/AHHEG and the AMAP (Arctic Monitoring and Assessment Programme within the Arctic Council) Human Health Assessment Group, AMAP/HHAG. In December 2012, workshop discussions were performed with representatives from both of these organizations, including 7 Arctic countries. The aim of this article is to describe the workshop discussions and the rational for the 12 indicators selected and the 9 rejected and to discuss the potential feasibility of these. Advantages and disadvantages of candidate indicators were listed. Informative value and costs for collecting were estimated separately on a 3-level scale: low, medium and high. Based on these reviews, the final selection of promoted and rejected indicators was performed and summarized in tables. Among 10 suggested indicators of food security, 6 were promoted: healthy weight, traditional food proportion in diet, monetary food costs, non-monetary food accessibility, food-borne diseases and food-related contaminants. Four were rejected: per-person dietary energy supply, food security modules, self-estimated food safety and healthy eating. Among 10 suggested indicators of water security, 6 were promoted: per-capita renewable water, accessibility of running water, waterborne diseases, drinking-water-related contaminants, authorized water quality assurance and water safety plans. Four were rejected: water consumption, types of water sources, periodic water shortages and household water costs.
Nilsson, Lena Maria; Berner, James; Dudarev, Alexey A.; Mulvad, Gert; Odland, Jon Øyvind; Parkinson, Alan; Rautio, Arja; Tikhonov, Constantine; Evengård, Birgitta
2013-01-01
In August 2012, a literature search with the aim of describing indicators on food and water security in an Arctic health context was initialized in collaboration between the Arctic Human Health Expert Group, SDWG/AHHEG and the AMAP (Arctic Monitoring and Assessment Programme within the Arctic Council) Human Health Assessment Group, AMAP/HHAG. In December 2012, workshop discussions were performed with representatives from both of these organizations, including 7 Arctic countries. The aim of this article is to describe the workshop discussions and the rational for the 12 indicators selected and the 9 rejected and to discuss the potential feasibility of these. Advantages and disadvantages of candidate indicators were listed. Informative value and costs for collecting were estimated separately on a 3-level scale: low, medium and high. Based on these reviews, the final selection of promoted and rejected indicators was performed and summarized in tables. Among 10 suggested indicators of food security, 6 were promoted: healthy weight, traditional food proportion in diet, monetary food costs, non-monetary food accessibility, food-borne diseases and food-related contaminants. Four were rejected: per-person dietary energy supply, food security modules, self-estimated food safety and healthy eating. Among 10 suggested indicators of water security, 6 were promoted: per-capita renewable water, accessibility of running water, waterborne diseases, drinking-water-related contaminants, authorized water quality assurance and water safety plans. Four were rejected: water consumption, types of water sources, periodic water shortages and household water costs. PMID:23940840
NASA Technical Reports Server (NTRS)
1982-01-01
An automated water quality monitoring system was developed by Langley Research Center to meet a need of the Environmental Protection Agency (EPA). Designed for unattended operation in water depths up to 100 feet, the system consists of a subsurface buoy anchored in the water, a surface control unit (SCU) and a hydrophone link for acoustic communication between buoy and SCU. Primary functional unit is the subsurface buoy. It incorporates 16 cells for water sampling, plus sensors for eight water quality measurements. Buoy contains all the electronic equipment needed for collecting and storing sensor data, including a microcomputer and a memory unit. Power for the electronics is supplied by a rechargeable nickel cadmium battery that is designed to operate for about two weeks. Through hydrophone link the subsurface buoy reports its data to the SCU, which relays it to land stations. Link allows two-way communications. If system encounters a problem, it automatically shuts down and sends alert signal. Sequence of commands sent via hydrophone link causes buoy to release from anchor and float to the surface for recovery.
Skaalvik, Mari Wolff; Gaski, Margrete; Norbye, Bente
2014-01-01
Background Ensuring a sufficient nursing workforce, with respect to both number and relevant professional competencies, is crucial in rural Arctic regions in Norway. This study examines the continuing education (CE) of nurses who graduated from a decentralized nursing programme between 1994 and 2011. Objective This study aims to measure the extent to which the decentralized nursing education (DNE) in question has served as a basis for CE that is adapted to current and future community health care service needs in rural Arctic regions in northern Norway. More specifically, the study aims to investigate the frequency and scope of CE courses among the graduates of a DNE, the choice of study model and the degree of employment with respect to the relevant CE. Design This study is a quantitative survey providing descriptive statistics. Results The primary finding in this study is that 56% of the participants had engaged in CE and that they were employed in positions related to their education. The majority of students with decentralized bachelor's degrees engaged in CE that was part time and/or decentralized. Conclusions More than half of the population in this study had completed CE despite no mandatory obligation in order to maintain licensure. Furthermore, 31% of the participants had completed more than one CE programme. The findings show that the participants preferred CE organized as part time and or decentralized studies. PMID:25279355
The impact of short-term heat storage on the ice-albedo feedback loop
NASA Astrophysics Data System (ADS)
Polashenski, C.; Wright, N.; Perovich, D. K.; Song, A.; Deeb, E. J.
2016-12-01
The partitioning of solar energy in the ice-ocean-atmosphere environment is a powerful control over Arctic sea ice mass balance. Ongoing transitions of the sea ice toward a younger, thinner state are enhancing absorption of solar energy and contributing to further declines in sea ice in a classic ice-albedo feedback. Here we investigate the solar energy balance over shorter timescales. In particular, we are concerned with short term delays in the transfer of absorbed solar energy to the ice caused by heat storage in the upper ocean. By delaying the realization of ice melt, and hence albedo decline, heat storage processes effectively retard the intra-season ice-albedo feedback. We seek to quantify the impact and variability of such intra-season storage delays on full season energy absorption. We use in-situ data collected from Arctic Observing Network (AON) sea ice sites, synthesized with the results of imagery processed from high resolution optical satellites, and basin-scale remote sensing products to approach the topic. AON buoys are used to monitor the storage and flux of heat, while satellite imagery allows us to quantify the evolution of surrounding ice conditions and predict the aggregate scale solar absorption. We use several test sites as illustrative cases and demonstrate that temporary heat storage can have substantial impacts on seasonal energy absorption and ice loss. A companion to this work is presented by N. Wright at this meeting.
Observation of melt onset on multiyear Arctic sea ice using the ERS 1 synthetic aperture radar
NASA Technical Reports Server (NTRS)
Winebrenner, D. P.; Nelson, E. D.; Colony, R.; West, R. D.
1994-01-01
We present nearly coincident observations of backscattering from the Earth Remote-Sensing Satellite (ERS) 1 synthetic aperture radar (SAR) and of near-surface temperature from six drifting buoys in the Beaufort Sea, showing that the onset of melting in snow on multiyear sea ice is clearly detectable in the SAR data. Melt onset is marked by a clean, steep decrease in the backscattering cross section of multiyear ice at 5.3 GHz and VV polarization. We investigate the scattering physics responsible for the signature change and find that the cross section decrease is due solely to the appearance of liquid water in the snow cover overlying the ice. A thin layer of moist snow is sufficient to cause the observed decrease. We present a prototype algorithm to estimate the date of melt onset using the ERS 1 SAR and apply the algorithm first to the SAR data for which we have corresponding buoy temperatures. The melt onset dates estimated by the SAR algorithm agree with those obtained independently from the temperature data to within 4 days or less, with the exception of one case in which temperatures oscillated about 0 C for several weeks. Lastly, we apply the algorithm to the entire ERS 1 SAR data record acquired by the Alaska SAR Facility for the Beaufort Sea north of 73 deg N during the spring of 1992, to produce a map of the dates of melt onset over an area roughly 1000 km on a side. The progression of melt onset is primarily poleward but shows a weak meridional dependence at latitudes of approximately 76 deg-77 deg N. Melting begins in the southern part of the study region on June 13 and by June 20 has progressed to the northermost part of the region.
Remote sensing data acquisition, analysis and archival. Volume 1. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stringer, W.J.; Dean, K.G.; Groves, J.E.
1993-03-25
The project specialized in the acquisition and dissemination of satellite imagery and its utilization for case-specific and statistical analyses of offshore environmental conditions, particularly those involving sea ice. During the duration of this contract, 854 Landsat Multispectral Scanner and 2 Landsat Thematic Mapper scenes, 8,576 Advanced Very High Resolution Radiometer images, and 31,000 European, Earth Resources Satellite, Synthetic Aperture Radar images were archived. Direct assistance was provided to eight Minerals Management Service (MMS)-sponsored studies, including analyses of Port Moller circulation, Bowhead whale migration, distribution, population and behavioral studies, Beaufort Sea fisheries, oil spill trajectory model development, and Kasegaluk Lagoon environmentalmore » assessments. In addition, under this Cooperative Agreement several complete studies were undertaken based on analysis of satellite imagery. The topics included: Kasegaluk Lagoon transport, the effect of winter storms on arctic ice, the relationship between ice surface temperatures as measured by buoys and passive microwave imagery, unusual cloud forms following lead-openings, and analyses of Chukchi and Bering sea polynyas.« less
46 CFR 160.050-7 - Procedure for approval.
Code of Federal Regulations, 2012 CFR
2012-10-01
...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular Plastic § 160.050-7 Procedure for approval. (a) General. Designs of ring life buoys are approved only by the Commandant, U.S. Coast Guard. Manufacturers seeking approval of a ring life buoy design shall follow the...
46 CFR 160.050-7 - Procedure for approval.
Code of Federal Regulations, 2014 CFR
2014-10-01
...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular Plastic § 160.050-7 Procedure for approval. (a) General. Designs of ring life buoys are approved only by the Commandant, U.S. Coast Guard. Manufacturers seeking approval of a ring life buoy design shall follow the...
46 CFR 160.050-7 - Procedure for approval.
Code of Federal Regulations, 2010 CFR
2010-10-01
...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular Plastic § 160.050-7 Procedure for approval. (a) General. Designs of ring life buoys are approved only by the Commandant, U.S. Coast Guard. Manufacturers seeking approval of a ring life buoy design shall follow the...
46 CFR 160.050-7 - Procedure for approval.
Code of Federal Regulations, 2011 CFR
2011-10-01
...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular Plastic § 160.050-7 Procedure for approval. (a) General. Designs of ring life buoys are approved only by the Commandant, U.S. Coast Guard. Manufacturers seeking approval of a ring life buoy design shall follow the...
46 CFR 160.050-7 - Procedure for approval.
Code of Federal Regulations, 2013 CFR
2013-10-01
...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular Plastic § 160.050-7 Procedure for approval. (a) General. Designs of ring life buoys are approved only by the Commandant, U.S. Coast Guard. Manufacturers seeking approval of a ring life buoy design shall follow the...
UpTempO Buoys for Understanding and Prediction
2014-09-30
between the Delrin plastic pod housing and the thermistor epoxy potting. (b) Buoy ship deployment. Three Metocean-manufactured UpTempO buoys were ship...2 and 3). The box is held together with only glue and paper tape. The sensor cable is housed in an inner cardboard box that eventually separates
47 CFR 90.248 - Wildlife and ocean buoy tracking.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 5 2014-10-01 2014-10-01 false Wildlife and ocean buoy tracking. 90.248... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.248 Wildlife... tracking of, and the telemetry of scientific data from, ocean buoys and animal wildlife. (b) Transmitters...
47 CFR 90.248 - Wildlife and ocean buoy tracking.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 5 2011-10-01 2011-10-01 false Wildlife and ocean buoy tracking. 90.248... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.248 Wildlife... tracking of, and the telemetry of scientific data from, ocean buoys and animal wildlife. (b) Transmitters...
47 CFR 90.248 - Wildlife and ocean buoy tracking.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Wildlife and ocean buoy tracking. 90.248... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.248 Wildlife... tracking of, and the telemetry of scientific data from, ocean buoys and animal wildlife. (b) Transmitters...
47 CFR 90.248 - Wildlife and ocean buoy tracking.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 5 2012-10-01 2012-10-01 false Wildlife and ocean buoy tracking. 90.248... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.248 Wildlife... tracking of, and the telemetry of scientific data from, ocean buoys and animal wildlife. (b) Transmitters...
47 CFR 90.248 - Wildlife and ocean buoy tracking.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 5 2013-10-01 2013-10-01 false Wildlife and ocean buoy tracking. 90.248... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.248 Wildlife... tracking of, and the telemetry of scientific data from, ocean buoys and animal wildlife. (b) Transmitters...
! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding . Mariners can now hear the latest coastal and offshore weather observations using Dial-A-Buoy. Dial-A-Buoy wind and wave measurements taken within the last hour at 65 buoy and 54 Coastal-Marine Automated
33 CFR 149.322 - Where must ring life buoys be located and how must they be stowed?
Code of Federal Regulations, 2010 CFR
2010-07-01
... both these requirements. (b) Each ring life buoy must be stowed on or in a rack that is readily accessible in an emergency. The ring life buoy must not be permanently secured in any way to the rack or the...
Effect of Sampling Depth on Air-Sea CO2 Flux Estimates in River-Stratified Arctic Coastal Waters
NASA Astrophysics Data System (ADS)
Miller, L. A.; Papakyriakou, T. N.
2015-12-01
In summer-time Arctic coastal waters that are strongly influenced by river run-off, extreme stratification severely limits wind mixing, making it difficult to effectively sample the surface 'mixed layer', which can be as shallow as 1 m, from a ship. During two expeditions in southwestern Hudson Bay, off the Nelson, Hayes, and Churchill River estuaries, we confirmed that sampling depth has a strong impact on estimates of 'surface' pCO2 and calculated air-sea CO2 fluxes. We determined pCO2 in samples collected from 5 m, using a typical underway system on the ship's seawater supply; from the 'surface' rosette bottle, which was generally between 1 and 3 m; and using a niskin bottle deployed at 1 m and just below the surface from a small boat away from the ship. Our samples confirmed that the error in pCO2 derived from typical ship-board versus small-boat sampling at a single station could be nearly 90 μatm, leading to errors in the calculated air-sea CO2 flux of more than 0.1 mmol/(m2s). Attempting to extrapolate such fluxes over the 6,000,000 km2 area of the Arctic shelves would generate an error approaching a gigamol CO2/s. Averaging the station data over a cruise still resulted in an error of nearly 50% in the total flux estimate. Our results have implications not only for the design and execution of expedition-based sampling, but also for placement of in-situ sensors. Particularly in polar waters, sensors are usually deployed on moorings, well below the surface, to avoid damage and destruction from drifting ice. However, to obtain accurate information on air-sea fluxes in these areas, it is necessary to deploy sensors on ice-capable buoys that can position the sensors in true 'surface' waters.
Seasonal Changes of Arctic Sea Ice Physical Properties Observed During N-ICE2015: An Overview
NASA Astrophysics Data System (ADS)
Gerland, S.; Spreen, G.; Granskog, M. A.; Divine, D.; Ehn, J. K.; Eltoft, T.; Gallet, J. C.; Haapala, J. J.; Hudson, S. R.; Hughes, N. E.; Itkin, P.; King, J.; Krumpen, T.; Kustov, V. Y.; Liston, G. E.; Mundy, C. J.; Nicolaus, M.; Pavlov, A.; Polashenski, C.; Provost, C.; Richter-Menge, J.; Rösel, A.; Sennechael, N.; Shestov, A.; Taskjelle, T.; Wilkinson, J.; Steen, H.
2015-12-01
Arctic sea ice is changing, and for improving the understanding of the cryosphere, data is needed to describe the status and processes controlling current seasonal sea ice growth, change and decay. We present preliminary results from in-situ observations on sea ice in the Arctic Basin north of Svalbard from January to June 2015. Over that time, the Norwegian research vessel «Lance» was moored to in total four ice floes, drifting with the sea ice and allowing an international group of scientists to conduct detailed research. Each drift lasted until the ship reached the marginal ice zone and ice started to break up, before moving further north and starting the next drift. The ship stayed within the area approximately 80°-83° N and 5°-25° E. While the expedition covered measurements in the atmosphere, the snow and sea ice system, and in the ocean, as well as biological studies, in this presentation we focus on physics of snow and sea ice. Different ice types could be investigated: young ice in refrozen leads, first year ice, and old ice. Snow surveys included regular snow pits with standardized measurements of physical properties and sampling. Snow and ice thickness were measured at stake fields, along transects with electromagnetics, and in drillholes. For quantifying ice physical properties and texture, ice cores were obtained regularly and analyzed. Optical properties of snow and ice were measured both with fixed installed radiometers, and from mobile systems, a sledge and an ROV. For six weeks, the surface topography was scanned with a ground LIDAR system. Spatial scales of surveys ranged from spot measurements to regional surveys from helicopter (ice thickness, photography) during two months of the expedition, and by means of an array of autonomous buoys in the region. Other regional information was obtained from SAR satellite imagery and from satellite based radar altimetry. The analysis of the data collected has started, and first results will be presented.
NASA Astrophysics Data System (ADS)
Chevooruvalappil Chandran, B.; Pittana, M.; Haas, C.
2015-12-01
Snow on sea ice is a critical and complex factor influencing sea ice processes. Deep snow with a high albedo and low thermal conductivity inhibits ice growth in winter and minimizes ice loss in summer. Very shallow or absent snow promotes ice growth in winter and ice loss in summer. The timing of snow ablation critically impacts summer sea ice mass balance. Here we assess the accuracy of various snow on sea ice data products from reanalysis and modeling comparing them with in situ measurements. The latter are based on the Warren et al. (1999) monthly climatology derived from snow ruler measurements between 1954-1991, and on daily snow depth retrievals from few drifting ice mass balance buoys (IMB) with sufficiently long observations spanning the summer season. These were compared with snow depth data from the National Center for Environmental Prediction Department of Energy Reanalysis 2 (NCEP), the Community Climate System Model 4 (CCSM4), and the Canadian Earth System Model 2 (CanESM2). Results are quite variable in different years and regions. However, there is often good agreement between CanESM2 and IMB snow depth during the winter accumulation and spring melt periods. Regional analyses show that over the western Arctic covered primarily with multiyear ice NCEP snow depths are in good agreement with the Warren climatology while CCSM4 overestimates snow depth. However, in the Eastern Arctic which is dominated by first-year ice the opposite behavior is observed. Compared to the Warren climatology CanESM2 underestimates snow depth in all regions. Differences between different snow depth products are as large as 10 to 20 cm, with large consequences for the sea ice mass balance. However, it is also very difficult to evaluate the accuracy of reanalysis and model snow depths due to a lack of extensive, continuous in situ measurements.
NASA Astrophysics Data System (ADS)
Valentic, T. A.
2012-12-01
The Data Transport Network is designed for the delivery of data from scientific instruments located at remote field sites with limited or unreliable communications. Originally deployed at the Sondrestrom Research Facility in Greenland over a decade ago, the system supports the real-time collection and processing of data from large instruments such as incoherent scatter radars and lidars. In recent years, the Data Transport Network has been adapted to small, low-power embedded systems controlling remote instrumentation platforms deployed throughout the Arctic. These projects include multiple buoys from the O-Buoy, IceLander and IceGoat programs, renewable energy monitoring at the Imnavait Creek and Ivotuk field sites in Alaska and remote weather observation stations in Alaska and Greenland. This presentation will discuss the common communications controller developed for these projects. Although varied in their application, each of these systems share a number of common features. Multiple instruments are attached, each of which needs to be power controlled, data sampled and files transmitted offsite. In addition, the power usage of the overall system must be minimized to handle the limited energy available from sources such as solar, wind and fuel cells. The communications links are satellite based. The buoys and weather stations utilize Iridium, necessitating the need to handle the common drop outs and high-latency, low-bandwidth nature of the link. The communications controller is an off-the-shelf, low-power, single board computer running a customized version of the Linux operating system. The Data Transport Network provides a Python-based software framework for writing individual data collection programs and supplies a number of common services for configuration, scheduling, logging, data transmission and resource management. Adding a new instrument involves writing only the necessary code for interfacing to the hardware. Individual programs communicate with the system services using XML-RPC. The scheduling algorithms have access the current position and power levels, allowing for instruments such as cameras to only be run during daylight hours or when sufficient power is available. The resource manager monitors the use of common devices such as the USB bus or Ethernet ports, and can power them down when they are not being used. This management lets us drop the power consumption from an average of 1W to 250mW.
Development of a new tubular buoy for seafloor geodetic observation with cabled system
NASA Astrophysics Data System (ADS)
Kido, M.; Osada, Y.; Fujimoto, H.; Kaneda, Y.
2008-12-01
Seafloor geodetic observation using the GPS/acoustic technique is now a practical tool to monitor crustal movement beneath the ocean. The DONET project, which plans to install a seafloor cable system and is promoted by MEXT, Japan is a promising candidate to achieve semi-realtime and long-term seafloor observation. However there still remain some technical problem for the system. One of the largest problem is the stability and safety of a mooring buoy for long-term. A box-type small buoy as a surface platform, which is out present system, heavily oscillates with ocean swells especially for short waves and has large friction against ocean current within water. To overcome this problem, we have developed a new buoy as a prototype of long-term mooring system. Since the new buoy is tubular in shape and more than 4 m height, its attitude at the sea surface is quite stable. A typical oscillating period is improved from 2 sec for the box-type buoy into more than 6 sec for the new tubular buoy. Further more, effect of multiple reflection against sea surface or bottom of the buoy is almost disappear due to its acoustic transducer locates at greater depth (around 3 m). We have confirmed that observed acoustic signals of the reply from seafloor transponders are quite clear and has small and symmetric siderobes in the correlogram, which is important for proper traveltime detection. The new buoy is designed as low power and remote controlled system, which is also suitable for future cable connection. Using this new system, we have conducted a test survey for several hours in Kumano-nada, along Nankai trough, where the seafloor cable is planed to be laid. At this site we have placed a seafloor transponders' array with five instruments rather than usual three transponders. This will help to estimate lateral gradient of sound speed structure in the ocean, which degrade positioning accuracy in the past survey and analytic styles. In this talk, we present the initial result of the survey using the new buoy.
Barrier Island Restoration for Storm Damage Reduction: Willapa Bay, Washington, USA
2010-07-01
Harbor Coastal Data Information Program ( CDIP ) 036 buoy located 13 miles northwest of the Entrance are utilized to specify the offshore wave boundary...condition. For the case of the March 3, 1999 storm, there is a gap in the CDIP buoy data; therefore the spectra from the National Data Buoy Center
Waves, Hydrodynamics and Sediment Transport Modeling at Grays Harbor, WA
2010-12-01
Grays Harbor Federal navigation project. At the same time, offshore wind and wave data were available from NDBC Buoy 46029 and CDIP Buoy 036 / NDBC...is forced by the regional ADCIRC water levels and currents, surface wind field, and offshore waves based on the CDIP Buoy 036 (NDBC 46211). Figures
Experimental design for drifting buoy Lagrangian test
NASA Technical Reports Server (NTRS)
Saunders, P. M.
1975-01-01
A test of instrumentation fabricated to measure the performance of a free drifting buoy as a (Lagrangian) current meter is described. Specifically it is proposed to distinguish between the trajectory of a drogued buoy and the trajectory of the water at the level of the drogue by measuring the flow relative to the drogue.
33 CFR 62.23 - Beacons and buoys.
Code of Federal Regulations, 2010 CFR
2010-07-01
... navigation. The primary components of the U.S. Aids to Navigation System are beacons and buoys. (b) Beacons are aids to navigation structures which are permanently fixed to the earth's surface. They range from... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.23 Beacons and buoys. (a...
33 CFR 62.23 - Beacons and buoys.
Code of Federal Regulations, 2011 CFR
2011-07-01
... navigation. The primary components of the U.S. Aids to Navigation System are beacons and buoys. (b) Beacons are aids to navigation structures which are permanently fixed to the earth's surface. They range from... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.23 Beacons and buoys. (a...
33 CFR 62.23 - Beacons and buoys.
Code of Federal Regulations, 2013 CFR
2013-07-01
... navigation. The primary components of the U.S. Aids to Navigation System are beacons and buoys. (b) Beacons are aids to navigation structures which are permanently fixed to the earth's surface. They range from... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.23 Beacons and buoys. (a...
33 CFR 62.23 - Beacons and buoys.
Code of Federal Regulations, 2014 CFR
2014-07-01
... navigation. The primary components of the U.S. Aids to Navigation System are beacons and buoys. (b) Beacons are aids to navigation structures which are permanently fixed to the earth's surface. They range from... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.23 Beacons and buoys. (a...
33 CFR 62.23 - Beacons and buoys.
Code of Federal Regulations, 2012 CFR
2012-07-01
... navigation. The primary components of the U.S. Aids to Navigation System are beacons and buoys. (b) Beacons are aids to navigation structures which are permanently fixed to the earth's surface. They range from... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.23 Beacons and buoys. (a...
Kallenborn, Roland; Brorström-Lundén, Eva; Reiersen, Lars-Otto; Wilson, Simon
2017-07-31
A first review on occurrence and distribution of pharmaceuticals and personal care products (PPCPs) is presented. The literature survey conducted here was initiated by the current Assessment of the Arctic Monitoring and Assessment Programme (AMAP). This first review on the occurrence and environmental profile of PPCPs in the Arctic identified the presence of 110 related substances in the Arctic environment based on the reports from scientific publications, national and regional assessments and surveys, as well as academic research studies (i.e., PhD theses). PPCP residues were reported in virtually all environmental compartments from coastal seawater to high trophic level biota. For Arctic environments, domestic and municipal wastes as well as sewage are identified as primary release sources. However, the absence of modern waste water treatment plants (WWTPs), even in larger settlements in the Arctic, is resulting in relatively high release rates for selected PPCPs into the receiving Arctic (mainly) aquatic environment. Pharmaceuticals are designed with specific biochemical functions as a part of an integrated therapeutically procedure. This biochemical effect may cause unwanted environmental toxicological effects on non-target organisms when the compound is released into the environment. In the Arctic environments, pharmaceutical residues are released into low to very low ambient temperatures mainly into aqueous environments. Low biodegradability and, thus, prolonged residence time must be expected for the majority of the pharmaceuticals entering the aquatic system. The environmental toxicological consequence of the continuous PPCP release is, thus, expected to be different in the Arctic compared to the temperate regions of the globe. Exposure risks for Arctic human populations due to consumption of contaminated local fish and invertebrates or through exposure to resistant microbial communities cannot be excluded. However, the scientific results reported and summarized here, published in 23 relevant papers and reports (see Table S1 and following references), must still be considered as indication only. Comprehensive environmental studies on the fate, environmental toxicology, and distribution profiles of pharmaceuticals applied in high volumes and released into the Nordic environment under cold Northern climate conditions should be given high priority by national and international authorities.
J. Brown; V.E. Romanovsky
2008-01-01
Recent assessments have considered present-day and future responses of permafrost terrain to climate change; included are the Intergovernmental Panel on Climate Change (IPCC) , Arctic Climate Impact Assessment (ACIA) and United Nations Environment Programme assessments (Romanovsky et al., 2007), the on-going National Oceanic and Atmospheric Administration (NOAA) annual...
Seafloor horizontal positioning from a continuously operating buoy-based GPS-acoustic array
NASA Astrophysics Data System (ADS)
Chadwell, C. D.; Brown, K. M.; Tryon, M. D.; Send, U.
2009-12-01
Seafloor horizontal positions in a global frame were estimated daily from an autonomous buoy operating continuously over several months. The buoy (GEOCE) was moored offshore San Diego in 100-m-deep waters above an array of 4 seafloor transponders. Dual-frequency GPS data were collected at 1-Hz at a main antenna on the buoy and at 3 shore stations to provide continuous 2-3 cm positions of the buoy main antenna. Two single-frequency antennas on the buoy along with the main antenna were used to estimate the buoy attitude and short-term velocity. At one minute intervals the two-way acoustic travel time was measured between the buoy and transponders. During this few second span when transmitting and receiving acoustic signals, 10-Hz attitude and velocity were collected to locate the position of the transducer mounted approximately 2 m below the water line. The GPS and acoustic data were recorded internally and transmitted to shore over a cell-phone link and/or a wireless Ethernet. GPS data were combined with the acoustic data to estimate the array location at 1 minute intervals. The 1-minute positions are combined to provide a daily estimate of the array position. The buoy is autonomous, solar-powered and in addition to the GPS and acoustic data collects air pressure, temperature, wind speed/direction as well as water level at the surface and conductivity and temperature along the mooring line from near the sea surface to just above the sea floor. Here we report results from the horizontal positioning effort from Phase I of the project in shallow waters. The project also includes a vertical deformation sensor and physical oceanographic monitoring. A deep water (nominally 1000 m) test is planned for 2010. This work is supported by NSF-OCE-0551363 of the Ocean Technology and Interdisciplinary Coordination Program.
Design, fabrication and systems integration of a satellite tracked, free-drifting ocean data buoy
NASA Technical Reports Server (NTRS)
Wallace, J. W.; Cox, J. W.
1976-01-01
Engineering details are presented of a small free-drifting buoy configuration designed for use in the study of continental shelf water circulation patterns in the Chesapeake Bight of the Western North Atlantic Ocean. The buoy incoporated French instrumentation and was interrogated by the French EOLE satellite to provide position and four channels of temperature data. The buoy design included a variable depth drogue and a power supply sufficient for six weeks of continuous operations. Proof tests of the configuration indicated an adequate design and subsequent field experiments verified the proper functioning of the system.
Wilkinson, Jeremy; Beegle-Krause, C J; Evers, Karl-Ulrich; Hughes, Nick; Lewis, Alun; Reed, Mark; Wadhams, Peter
2017-12-01
Renewed political and commercial interest in the resources of the Arctic, the reduction in the extent and thickness of sea ice, and the recent failings that led to the Deepwater Horizon oil spill, have prompted industry and its regulatory agencies, governments, local communities and NGOs to look at all aspects of Arctic oil spill countermeasures with fresh eyes. This paper provides an overview of present oil spill response capabilities and technologies for ice-covered waters, as well as under potential future conditions driven by a changing climate. Though not an exhaustive review, we provide the key research results for oil spill response from knowledge accumulated over many decades, including significant review papers that have been prepared as well as results from recent laboratory tests, field programmes and modelling work. The three main areas covered by the review are as follows: oil weathering and modelling; oil detection and monitoring; and oil spill response techniques.
Holtschlag, David J.; Syed, Atiq U.; Kennedy, Gregory W.
2002-01-01
Lake St. Clair is a 430 square mile lake between the state of Michigan and the province of Ontario, which forms part of the international boundary between the United States and Canada in the Great Lakes Basin. Lake St. Clair receives most of its inflow from Lake Huron through St. Clair River, which has an average flow of 182,000 cubic feet per second. The lake discharges to Detroit River, where it flows 32 miles to Lake Erie. Twelve drifting buoys were deployed on Lake St. Clair for 74 hours between August 12-15, 2002 to help investigate flow circulation patterns as part of a source water assessment study of the susceptibility of public water intakes. The buoys contained global positioning system (GPS) receivers to track their movements. Buoys were released in a transect between tethered buoys marking an 800-foot wide navigational channel in the north-central part of the lake just downstream of St. Clair River, and about 15.5 miles northeast of Detroit River. In addition, an acoustic Doppler current profiler (ADCP) was used to measure velocity profiles in a grid of 41 points that spanned the area through which the buoys drifted. Computer animations, which can be viewed through the Internet, were developed to help visualize the results of the buoy deployments and ADCP measurements.
PIPOR - A Programme for International Polar Oceans Research
NASA Technical Reports Server (NTRS)
Gudmandsen, P.; Carsey, F.; Mcnutt, L.
1989-01-01
The Programme for International Polar Oceans Research is accepted as a part of the ERS-1 mission which will be initiated with the launch of the ERS-1 earth observation satellite by the European Space Agency in 1990. It is a bipolar program with participation by institutions engaged in studies of the atmosphere-ocean-sea ice interaction and the application of remote sensing data for operational uses. The program objectives are to develop the application of microwave data for studies and modeling of sea ice dynamics and for operational uses in sea ice infested areas. As such, it is closely connected with ongoing and forthcoming research in the Arctic and the Antarctic. With sea ice being a sensitive indicator of climate perturbations, PIPOR addresses objectives of the World Climate Research Programme.
33 CFR 149.321 - How many ring life buoys must be on each deepwater port?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false How many ring life buoys must be on each deepwater port? 149.321 Section 149.321 Navigation and Navigable Waters COAST GUARD... EQUIPMENT Lifesaving Equipment Manned Deepwater Port Requirements § 149.321 How many ring life buoys must be...
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 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...
Calibration of Ocean Wave Measurements by the TOPEX, Jason-1, and Jason-2 Satellites
NASA Technical Reports Server (NTRS)
Ray, Richard D.; Beckley, B. D.
2012-01-01
The calibration and validation of ocean wave height measurements by the TOPEX, Jason-1, and Jason-2 satellite altimeters is addressed by comparing the measurements internally among them- selves and against independent wave measurements at moored buoys. The two six-month verification campaigns, when two of the satellites made near-simultaneous measurements along the same ground track, are invaluable for such work and reveal subtle aspects that otherwise might go undetected. The two Jason satellites are remarkably consistent; Topex reports waves generally 1-2% larger. External calibration is complicated by some systematic errors in the buoy data. We confirm a recent report by Durrant et al. that Canadian buoys underestimate significant wave heights by about 10% relative to U.S. buoys. Wave heights from all three altimetric satellites require scaling upwards by 5 6% to be consistent with U.S. buoys.
Synthesizing International Understanding of Changes in the Arctic Hydrological System
NASA Astrophysics Data System (ADS)
Pundsack, J. W.; Vorosmarty, C. J.; Hinzman, L. D.
2009-12-01
There are several notable gaps in our current level of understanding of Arctic hydrological systems. At the same time, rapidly emerging data sets, technologies, and modeling resources provide us with an unprecedented opportunity to move substantially forward. The Arctic Community-Wide Hydrological Analysis and Monitoring Program (Arctic-CHAMP), funded by NSF/ARCSS, was established to initiate a major effort to improve our current monitoring of water cycle variables, and to foster collaboration with the many relevant U.S. and international arctic research initiatives. These projects, funded under ARCSS through the ‘Freshwater Integration (FWI) study’, links CHAMP, the Arctic/Subarctic Ocean Fluxes (ASOF) Programme, and SEARCH. As part of the overall synthesis and integration efforts of the NSF-ARCSS Freshwater Integration (FWI) study, the program carried-out a major International Synthesis Capstone Workshop in Fall 2009 as an International Polar Year (IPY) affiliated meeting. The workshop, "Synthesizing International Understanding of Changes in the Arctic Hydrological System,” was held 30 September to 4 October 2009 in Stockholm at the Beijer Auditorium of the Royal Swedish Academy. The workshop was sponsored by the NSF-ARCSS Arctic-CHAMP Science Management Office (City College of New York / Univ. of New Hampshire), the International Study of Arctic Change (ISAC), and the International Arctic Research Center (IARC; Univ. of Alaska Fairbanks). The overarching goals of the meeting were to stage a post-IPY lessons-learned workshop with co-equal numbers of FWI, IPY, and ICARP-II researchers, using insights from recent scientific findings, data, and strategies to afford synthesis. The workshop aimed to: (1) take stock of recent advances in our understanding of changes in the Arctic hydrological system; (2) identify key remaining research gaps / unanswered questions; and (3) gather insight on where to focus future research efforts/initiatives (nationally and internationally). The workshop brought together approximately 40 participants, with roughly equal numbers from North America and Europe/Scandinavia, and included representatives from Canada, Russia, Germany, Iceland, Sweden, Norway, Finland, Denmark/Greenland, and the US. This talk will focus on findings of the workshop, highlighting advances in Arctic research that have taken flight over the last decade, specifically stimulated by considering the hydrologic cycle as an integrating force and fundamental building block uniting atmospheric, oceanic, cryospheric and terrestrial domains of the pan-Arctic system. The authors will present a future vision for systems-level science of Arctic hydrology and affiliated energy and carbon cycles. A scientific roadmap will be introduced, outlining the main research priorities, robust global and regional geo-information data products, improved models and effective data assimilation systems to forward the science of water in the Arctic.
Method and apparatus for production of subsea hydrocarbon formations
Blandford, Joseph W.
1995-01-01
A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external floatation tanks located below the water surface. The surface buoy is secured to the seabed by one or more tendons which are anchored to a foundation with piles imbedded in the seabed. The system accommodates multiple versions on the surface buoy configuration.
Design of Buoys for Mounting Wind Turbines at Exposed Sites
NASA Astrophysics Data System (ADS)
Erdoğan, Beytullah; Çelıkkol, Barbaros; Swift, Robinson
2018-04-01
In this study, two designs for a buoy capable of supporting a 10 kW wind turbine and its tower were developed to operate at the University of New Hampshire's Center of Ocean Renewable Energy testing site located off the Isles of Shoals, New Hampshire. The buoys are to be moored by a catenary chain system. To evaluate wave response, two Froude-scaled models were constructed, tested, and compared at the Ocean Engineering wave tank at the University of New Hampshire. These buoys have been implemented and compared with wave tank measurements of the spar displacement at a reference elevation 2.44 m above the mean water level.
Ocean power technology design optimization
van Rij, Jennifer; Yu, Yi -Hsiang; Edwards, Kathleen; ...
2017-07-18
For this study, the National Renewable Energy Laboratory and Ocean Power Technologies (OPT) conducted a collaborative code validation and design optimization study for OPT's PowerBuoy wave energy converter (WEC). NREL utilized WEC-Sim, an open-source WEC simulator, to compare four design variations of OPT's PowerBuoy. As an input to the WEC-Sim models, viscous drag coefficients for the PowerBuoy floats were first evaluated using computational fluid dynamics. The resulting WEC-Sim PowerBuoy models were then validated with experimental power output and fatigue load data provided by OPT. The validated WEC-Sim models were then used to simulate the power performance and loads for operationalmore » conditions, extreme conditions, and directional waves, for each of the four PowerBuoy design variations, assuming the wave environment of Humboldt Bay, California. And finally, ratios of power-to-weight, power-to-fatigue-load, power-to-maximum-extreme-load, power-to-water-plane-area, and power-to-wetted-surface-area were used to make a final comparison of the potential PowerBuoy WEC designs. Lastly, the design comparison methodologies developed and presented in this study are applicable to other WEC devices and may be useful as a framework for future WEC design development projects.« less
Ocean power technology design optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
van Rij, Jennifer; Yu, Yi -Hsiang; Edwards, Kathleen
For this study, the National Renewable Energy Laboratory and Ocean Power Technologies (OPT) conducted a collaborative code validation and design optimization study for OPT's PowerBuoy wave energy converter (WEC). NREL utilized WEC-Sim, an open-source WEC simulator, to compare four design variations of OPT's PowerBuoy. As an input to the WEC-Sim models, viscous drag coefficients for the PowerBuoy floats were first evaluated using computational fluid dynamics. The resulting WEC-Sim PowerBuoy models were then validated with experimental power output and fatigue load data provided by OPT. The validated WEC-Sim models were then used to simulate the power performance and loads for operationalmore » conditions, extreme conditions, and directional waves, for each of the four PowerBuoy design variations, assuming the wave environment of Humboldt Bay, California. And finally, ratios of power-to-weight, power-to-fatigue-load, power-to-maximum-extreme-load, power-to-water-plane-area, and power-to-wetted-surface-area were used to make a final comparison of the potential PowerBuoy WEC designs. Lastly, the design comparison methodologies developed and presented in this study are applicable to other WEC devices and may be useful as a framework for future WEC design development projects.« less
[Design and experimentation of marine optical buoy].
Yang, Yue-Zhong; Sun, Zhao-Hua; Cao, Wen-Xi; Li, Cai; Zhao, Jun; Zhou, Wen; Lu, Gui-Xin; Ke, Tian-Cun; Guo, Chao-Ying
2009-02-01
Marine optical buoy is of important value in terms of calibration and validation of ocean color remote sensing, scientific observation, coastal environment monitoring, etc. A marine optical buoy system was designed which consists of a main and a slave buoy. The system can measure the distribution of irradiance and radiance over the sea surface, in the layer near sea surface and in the euphotic zone synchronously, during which some other parameters are also acquired such as spectral absorption and scattering coefficients of the water column, the velocity and direction of the wind, and so on. The buoy was positioned by GPS. The low-power integrated PC104 computer was used as the control core to collect data automatically. The data and commands were real-timely transmitted by CDMA/GPRS wireless networks or by the maritime satellite. The coastal marine experimentation demonstrated that the buoy has small pitch and roll rates in high sea state conditions and thus can meet the needs of underwater radiometric measurements, the data collection and remote transmission are reliable, and the auto-operated anti-biofouling devices can ensure that the optical sensors work effectively for a period of several months.
Implementation of PLUTO Buoy for Monitoring Water Quality in Indonesia, Reflection and Future Plans
NASA Astrophysics Data System (ADS)
Chandra, H.; Krismono, K.; Kusumaningrum, P. D.; Sianturi, D.; Firdaus, Y.; Taukhid, I.; Borneo, B. B.
2016-02-01
Research and development of PLUTO (Perairan Selalu Termonitor/Waters Always Monitored) buoy has reached its fourth year in 2015. Try out has been done in coastal waters, fishponds, fishing port ponds, and reservoirs. In the first year (2010) try out has been performed on coastal waters with off line measurement system. The buoy used temperature, salinity, DO and pH sensors. In the second year (2013) try out was carried out on fishponds and fishing port ponds using telemetry measurement system. In the third year (2014) try out was carried out on water reservoir with telemetry measurement system. In the fourth year (2015) android application is developed to monitor 4 water reservoirs and 1 lake. Beside that, observation point is added to 3 point depth for one buoy. Parameters used are temperature, DO, and turbidity. Three PLUTO buoys are placed in each reservoir, at inlet, outlet, and at center of fish cultivation. Through Ocean Science Meeting in New Orleans it is hoped that there will be input and suggestion from the experts for future development of the monitoring system for public inland waters (especially reservoir and lake) in Indonesia. Keywords: buoy PLUTO, salinity, temperature, Dissolved Oxygen (DO), pH, turbidity, telemetry
AirSWOT flights and field campaigns for the 2017 Arctic-Boreal Vulnerability Experiment (ABoVE)
NASA Astrophysics Data System (ADS)
Smith, L. C.; Pavelsky, T.; Lettenmaier, D. P.; Gleason, C. J.; Pietroniro, A.; Applejohn, A.; Arvesen, J. C.; Bjella, K.; Carter, T.; Chao, R.; Cooley, S. W.; Cooper, M. G.; Cretaux, J. F.; Douglass, T.; Faria, D.; Fayne, J.; Fiset, J. M.; Goodman, S.; Hanna, B.; Harlan, M.; Langhorst, T.; Marsh, P.; Moreira, D. M.; Minear, J. T.; Onclin, C.; Overstreet, B. T.; Peters, D.; Pettit, J.; Pitcher, L. H.; Russell, M.; Spence, C.; Topp, S.; Turner, K. W.; Vimal, S.; Wilcox, E.; Woodward, J.; Yang, D.; Zaino, A.
2017-12-01
Some 50% of Canada and 80% of Alaska is thought to be underlain by permafrost, influencing the hydrology, ecology and carbon cycles of Arctic-Boreal landscapes. This influence includes enhanced presence of millions of lakes and wetlands, which release trace gases while supporting critical ecosystems and traditional subsistence economies. Permafrost is challenging to infer from remote sensing and difficult to sample in the field. A series of 2017 AirSWOT flights flown for the NASA Arctic-Boreal Vulnerability Experiment (ABoVE) will study whether small variations in water surface elevations (WSEs) of Arctic-Boreal lakes are sensitive to presence and/or disturbance of permafrost. AirSWOT is an experimental NASA airborne radar designed to map WSE and a precursor to SWOT, a forthcoming NASA/CNES/CSA satellite mission to map WSE globally with launch in 2021. The ABoVE AirSWOT flight experiments adopted long flight lines of the broader ABoVE effort to traverse broad spatial gradients of permafrost, climate, ecology, and geology. AirSWOT acquisitions consisted of long (1000s of kilometers) strips of Ka-band interferometric radar imagery, and high resolution visible/NIR imagery and DEMs from a digital Cirrus CIR camera. Intensive AirSWOT mapping and ground-based GPS field surveys were conducted at 11 field sites for eight study areas of Canada and Alaska: 1) Saint-Denis, Redberry Lake, North Saskatchewan River (Saskatchewan); 2) Peace-Athabasca Delta (Alberta); 3) Slave River Delta (N.W.T.); 4) Canadian Shield (Yellowknife area, Daring Lake, N.W.T.); 5) Mackenzie River (Inuvik-Tuktoyaktuk corridor, N.W.T.); 6) Old Crow Flats (Yukon Territory); 7) Sagavanirktok River (Alaska); 8) Yukon Flats (Alaska). Extensive ground campaigns were conducted by U.S. and Canadian collaborators to collect high quality surveys of lake WSE, river WSE and discharge, and shoreline locations. Field experiments included traditional and novel GPS surveying methods, including custom-built GPS buoys that float or drift upon water surfaces. Other ABoVE flight packages flown along AirSWOT lines included LVIS, AVIRIS, UAVSAR and AirMOSS. Processing and integration of ABoVE remote sensing and field datasets may provide new scientific insights about the influence of permafrost on surface water hydrology, over broad spatial scales.
Code of Federal Regulations, 2014 CFR
2014-07-01
... District Engineer and market by signs and/or flashing red lights installed in conspicuous and appropriate... structures located on the left-hand side (facing downstream) of the river and a black can-type buoy for such... buoy of appropriate type and color (red nun or black can buoy) until covered by a depth of water equal...
Code of Federal Regulations, 2013 CFR
2013-07-01
... District Engineer and market by signs and/or flashing red lights installed in conspicuous and appropriate... structures located on the left-hand side (facing downstream) of the river and a black can-type buoy for such... buoy of appropriate type and color (red nun or black can buoy) until covered by a depth of water equal...
Engineering Support for the Development of a Submersible Fish Cage for Open Ocean Aquaculture
2007-01-01
32 Appendix B: Feed Hose Buoy Components ................................................................. 33...ballasting systems (for test purposes) located in the upper rim section and airlift. Another component of the system includes a feed hose buoy used...to deliver pellets to fish in the cage while the system is submerged. Since the feed hose buoy was not critical in the development of the fish
Code of Federal Regulations, 2010 CFR
2010-07-01
... River, Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. 165.812 Section 165.812 Navigation..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi... Lower Mississippi River mile marker 96.0 in New Orleans, Louisiana. These moving security zones...
Real-time and on-demand buoy observation system for tsunami and crustal displacement
NASA Astrophysics Data System (ADS)
Takahashi, N.; Imai, K.; Ishihara, Y.; Fukuda, T.; Ochi, H.; Suzuki, K.; Kido, M.; Ohta, Y.; Imano, M.; Hino, R.
2017-12-01
We develop real-time and on-demand buoy observation system for tsunami and crustal displacement. It is indispensable for observation of crustal displacement to understand changes of stress field related to future large earthquakes. The current status of the observation is carried out by using a vessel with an interval of a few times per a year. When a large earthquake occurs, however, we need dense or on-demand observation of the crustal displacement to grasp nature of the slow slip after the rupture. Therefore, we constructed buoy system with a buoy station, wire-end station, seafloor unit and acoustic transponders for crustal displacement, and we installed a pressure sensor on the seafloor unit and GNSS system on the buoy in addition to measurement of e distance between the buoy and the seafloor acoustic transponders. Tsunami is evaluated using GNSS data and pressure data sent from seafloor. Observation error of the GNSS is about 10 cm. The crustal displacement is estimated using pressure sensor for vertical and acoustic measurement for horizontal. Using current slack ratio of 1.58, the observation error for the measurement of the crustal displacement is about 10 cm. We repeated three times sea trials and confirmed the data acquisition with high data quality, mooring without dredging anchor in the strong sea current with a speed of 5.5 knots. Current issues to be resolved we face are removing noises on the acoustic data transmission, data transmission between the buoy and wire-end stations, electrical consumption on the buoy station and large observation error on the crustal displacement due to large slack ratio. We consider the change of the acoustic transmission for pressure data, replace of a GNSS data logger with large electrical consumption, and reduce of the slack ratio, and search method to reduce resistance of the buoy on the sea water. In this presentation, we introduce the current status of the technical development and tsunami waveforms recorded on our seafloor unit using recent tsunami signals earthquake for the data quality check.
Is it ‘boom times’ for baleen whales in the Pacific Arctic region?
2016-01-01
The marine ecosystem in the Pacific Arctic region has experienced dramatic transformation, most obvious by the loss of sea ice volume (75%), late-summer areal extent (50%) and change in phenology (four to six weeks longer open-water period). This alteration has resulted in an opening of habitat for subarctic species of baleen whales, many of which are recovering in number from severe depletions from commercial whaling in the nineteenth and twentieth centuries. Specifically, humpback, fin and minke whales (Megaptera novaeangliae, Balaenoptera physalus and Balaenoptera acutorostrata) are now regularly reported during summer and autumn in the southern Chukchi Sea. These predators of zooplankton and forage fishes join the seasonally resident grey whale (Eschrichtius robustus) and the arctic-endemic bowhead whale (Balaena mysticetus) in the expanding open-ocean habitat of the Pacific Arctic. Questions arising include: (i) what changes in whale-prey production and delivery mechanisms have accompanied the loss of sea ice, and (ii) how are these five baleen whale species partitioning the expanding ice-free habitat? While there has been no programme of research specifically focused on these questions, an examination of seasonal occurrence, foraging plasticity and (for bowhead whales) body condition suggests that the current state of Pacific Arctic marine ecosystem may be ‘boom times’ for baleen whales. These favourable conditions may be moderated, however, by future shifts in ecosystem structure and/or negative impacts to cetaceans related to increased commercial activities in the region. PMID:27601724
Is it 'boom times' for baleen whales in the Pacific Arctic region?
Moore, Sue E
2016-09-01
The marine ecosystem in the Pacific Arctic region has experienced dramatic transformation, most obvious by the loss of sea ice volume (75%), late-summer areal extent (50%) and change in phenology (four to six weeks longer open-water period). This alteration has resulted in an opening of habitat for subarctic species of baleen whales, many of which are recovering in number from severe depletions from commercial whaling in the nineteenth and twentieth centuries. Specifically, humpback, fin and minke whales (Megaptera novaeangliae, Balaenoptera physalus and Balaenoptera acutorostrata) are now regularly reported during summer and autumn in the southern Chukchi Sea. These predators of zooplankton and forage fishes join the seasonally resident grey whale (Eschrichtius robustus) and the arctic-endemic bowhead whale (Balaena mysticetus) in the expanding open-ocean habitat of the Pacific Arctic. Questions arising include: (i) what changes in whale-prey production and delivery mechanisms have accompanied the loss of sea ice, and (ii) how are these five baleen whale species partitioning the expanding ice-free habitat? While there has been no programme of research specifically focused on these questions, an examination of seasonal occurrence, foraging plasticity and (for bowhead whales) body condition suggests that the current state of Pacific Arctic marine ecosystem may be 'boom times' for baleen whales. These favourable conditions may be moderated, however, by future shifts in ecosystem structure and/or negative impacts to cetaceans related to increased commercial activities in the region. © 2016 The Author(s).
Method and apparatus for production of subsea hydrocarbon formations
Blandford, J.W.
1995-01-17
A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external flotation tanks located below the water surface. The surface buoy is secured to the sea bed by one or more tendons which are anchored to a foundation with piles imbedded in the sea bed. The system accommodates multiple versions on the surface buoy configuration. 20 figures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
The objectives of the SNAP 7A program were to design, manufacture, test, and deliver a five-watt electric generation system for a U. S. Coast Guard 8 x 26E light buoy. The 10-watt Sr/sup 90/ thermoelectric generator, the d-c-to-d-c converter, batteries and the method of installation in the light buoy are describcd. The SNAP 7A generator was fueled with four capsules containing a total of 40,800 curies of Sr/sup 90/ titanate. After fueling and testing, the SNAP 7A electric generating system was installed in the Coast Guard light buoy at Baltimore, Maryland, on December 15, 1961. Operation of the buoy lampmore » is continuous. (auth)« less
Design of the dual-buoy wave energy converter based on actual wave data of East Sea
NASA Astrophysics Data System (ADS)
Kim, Jeongrok; Kweon, Hyuck-Min; Jeong, Weon-Mu; Cho, Il-Hyoung; Cho, Hong-Yeon
2015-07-01
A new conceptual dual-buoy Wave Energy Converter (WEC) for the enhancement of energy extraction efficiency is suggested. Based on actual wave data, the design process for the suggested WEC is conducted in such a way as to ensure that it is suitable in real sea. Actual wave data measured in Korea's East Sea (position: 36.404 N° and 129.274 E°) from May 1, 2002 to March 29, 2005 were used as the input wave spectrum for the performance estimation of the dual-buoy WEC. The suggested WEC, a point absorber type, consists of two concentric floating circular cylinders (an inner and a hollow outer buoy). Multiple resonant frequencies in proposed WEC affect the Power Ttake-off (PTO) performance of the WEC. Based on the numerical results, several design strategies are proposed to further enhance the extraction efficiency, including intentional mismatching among the heave natural frequencies of dual buoys, the natural frequency of the internal fluid, and the peak frequency of the input wave spectrum.
Study of hydrodynamic characteristics of a Sharp Eagle wave energy converter
NASA Astrophysics Data System (ADS)
Zhang, Ya-qun; Sheng, Song-wei; You, Ya-ge; Huang, Zhen-xin; Wang, Wen-sheng
2017-06-01
According to Newton's Second Law and the microwave theory, mechanical analysis of multiple buoys which form Sharp Eagle wave energy converter (WEC) is carried out. The movements of every buoy in three modes couple each other when they are affected with incident waves. Based on the above, mechanical models of the WEC are established, which are concerned with fluid forces, damping forces, hinge forces, and so on. Hydrodynamic parameters of one buoy are obtained by taking the other moving buoy as boundary conditions. Then, by taking those hydrodynamic parameters into the mechanical models, the optimum external damping and optimal capture width ratio are calculated out. Under the condition of the optimum external damping, a plenty of data are obtained, such as the displacements amplitude of each buoy in three modes (sway, heave, pitch), damping forces, hinge forces, and speed of the hydraulic cylinder. Research results provide theoretical references and basis for Sharp Eagle WECs in the design and manufacture.
Roseman, Edward F.; Kennedy, Gregory W.; Craig, Jaquelyn; Boase, James; Soper, Karen
2011-01-01
In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy-less method for sampling fish eggs and spawning activity using egg mats deployed on the river bottom. The buoy-less method allowed us to fish gear in areas frequented by boaters and recreational anglers, thus eliminating surface obstructions that interfered with recreational and boating activities. The buoy-less method also reduced gear loss due to drift when masses of floating aquatic vegetation would accumulate on buoys and lines, increasing the drag on the gear and pulling it downstream. Second, we adapted a D-frame drift net system formerly employed in shallow streams to assess larval lake sturgeon dispersal for use in the deeper (>8 m) Detroit River using an anchor and buoy system.
Roseman, E.F.; Boase, J.; Kennedy, G.; Craig, J.; Soper, K.
2011-01-01
In this report we describe how we adapted two techniques for sampling lake sturgeon (Acipenser fulvescens) and other fish early life history stages to meet our research needs in the Detroit River, a deep, flowing Great Lakes connecting channel. First, we developed a buoy-less method for sampling fish eggs and spawning activity using egg mats deployed on the river bottom. The buoy-less method allowed us to fish gear in areas frequented by boaters and recreational anglers, thus eliminating surface obstructions that interfered with recreational and boating activities. The buoy-less method also reduced gear loss due to drift when masses of floating aquatic vegetation would accumulate on buoys and lines, increasing the drag on the gear and pulling it downstream. Second, we adapted a D-frame drift net system formerly employed in shallow streams to assess larval lake sturgeon dispersal for use in the deeper (>8m) Detroit River using an anchor and buoy system. ?? 2011 Blackwell Verlag, Berlin.
Seasonal Ice Zone Reconnaissance Surveys Coordination and Ocean Profiles
2015-09-30
Morison), UpTempO buoy measurements of sea surface temperature (SST), sea level atmospheric pressure ( SLP ), and velocity (Steele), and dropsonde...dropsondes, micro-aircraft), cloud top/base heights UpTempO buoys for understanding and prediction…. Steele UpTempO buoy drops for SLP , SST, SSS...Air Expendable Current Profiler, SLP = Sea Level atmospheric Pressure, SST= Seas Surface Temperature, A/C= aircraft, SIC=Sea Ice Concentration We
33 CFR 165.704 - Safety Zone; Tampa Bay, Florida.
Code of Federal Regulations, 2011 CFR
2011-07-01
... safety zone starts at Tampa Bay Cut “F” Channel from Lighted Buoys “3F” and “4F” and proceeds north ending at Gadsden Point Cut Lighted Buoys “3” and “4”. The safety zone starts again at Gadsden Point Cut Lighted Buoys “7” and “8” and proceeds north through Hillsborough Cut “C”, Port Sutton Entrance Channel...
NASA Astrophysics Data System (ADS)
Alexandre, E.; Cuadra, L.; Nieto-Borge, J. C.; Candil-García, G.; del Pino, M.; Salcedo-Sanz, S.
2015-08-01
Wave parameters computed from time series measured by buoys (significant wave height Hs, mean wave period, etc.) play a key role in coastal engineering and in the design and operation of wave energy converters. Storms or navigation accidents can make measuring buoys break down, leading to missing data gaps. In this paper we tackle the problem of locally reconstructing Hs at out-of-operation buoys by using wave parameters from nearby buoys, based on the spatial correlation among values at neighboring buoy locations. The novelty of our approach for its potential application to problems in coastal engineering is twofold. On one hand, we propose a genetic algorithm hybridized with an extreme learning machine that selects, among the available wave parameters from the nearby buoys, a subset FnSP with nSP parameters that minimizes the Hs reconstruction error. On the other hand, we evaluate to what extent the selected parameters in subset FnSP are good enough in assisting other machine learning (ML) regressors (extreme learning machines, support vector machines and gaussian process regression) to reconstruct Hs. The results show that all the ML method explored achieve a good Hs reconstruction in the two different locations studied (Caribbean Sea and West Atlantic).
Design of a Low-cost Oil Spill Tracking Buoy
NASA Astrophysics Data System (ADS)
Zhao, Y.; Hu, X.; Yu, F.; Dong, S.; Chen, G.
2017-12-01
As the rapid development of oil exploitation and transportation, oil spill accidents, such as Prestige oil spill, Gulf of Mexico oil spill accident and so on, happened frequently in recent years which would result in long-term damage to the environment and human life. It would be helpful for rescue operation if we can locate the oil slick diffusion area in real time. Equipped with GNSS system, current tracking buoys(CTB), such as Lagrangian drifting buoy, Surface Velocity Program (SVP) drifter, iSLDMB (Iridium self locating datum marker buoy) and Argosphere buoy, have been used as oil tracking buoy in oil slick observation and as validation tools for oil spill simulation. However, surface wind could affect the movement of oil slick, which couldn't be reflected by CTB, thus the oil spill tracking performance is limited. Here, we proposed an novel oil spill tracking buoy (OSTB) which has a low cost of less than $140 and is equipped with Beidou positioning module and sails to track oil slick. Based on hydrodynamic equilibrium model and ocean dynamic analysis, the wind sails and water sails are designed to be adjustable according to different marine conditions to improve tracking efficiency. Quick release device is designed to assure easy deployment from air or ship. Sea experiment was carried out in Jiaozhou Bay, Northern China. OSTB, SVP, iSLDMB, Argosphere buoy and a piece of oil-simulated rubber sheet were deployed at the same time. Meanwhile, oil spill simulation model GNOME (general NOAA operational modeling environment) was configured with the wind and current field, which were collected by an unmanned surface vehicle (USV) mounted with acoustic Doppler current profilers (ADCP) and wind speed and direction sensors. Experimental results show that the OSTB has better relevance with rubber sheet and GNOME simulation results, which validate the oil tracking ability of OSTB. With low cost and easy deployment, OSTB provides an effective way for oil spill numerical modeling validation and quick response to oil spill accidents.
Gulf of Mexico Monitoring Via The Remotely Controlled CMR SailBuoy
NASA Astrophysics Data System (ADS)
Wienders, N.; Hole, L. R.; Peddie, D.
2013-12-01
The CMR SailBuoy is an unmanned ocean vessel capable of traveling the oceans for extended periods of time. It navigates the oceans autonomously - transmitting data at regular intervals using the Iridium network for two way communication. The SailBuoy can be used for a wide variety of ocean applications from measuring ocean and atmospheric parameters to tracking oil spills or acting as a communication relay station for subsea instrumentation. As part of the Deep-C project(Deep Sea to Coast Connectivity in the Eastern Gulf of Mexico), a two month campaign was carried out from March to May 2013 with the purpose of collecting sea surface data (temperature, salinity and oxygen) during the spring bloom. The campaign was unique in that the SailBouy was remotely controlled from Norway after being deployed from the RV Apalachee. The SailBuoy was deployed approximately 11 nautical miles (nm) south of Cape San Blas. During its mission she sailed approximately 840nm on a cruise track across the Gulf coast, from the Florida Panhandle to Louisiana. The SailBuoy project is part of Deep-C's physical oceanography research which seeks to, among other things, understand how particles and dissolved substances (such as oil) travel from the deep sea to the Louisiana, Mississippi, Alabama and Florida shorelines. This involves cross-shelf transport and upwelling mechanisms, which the SailBuoy is capable of measuring. An other focus was the sampling of the Mississippi river plume, which has been shown to influence the distribution of particles, oil, dissolved substances in the water, at least at the surface level. Sea surface salinity measurement via satellite do not provide, at the moment, sufficient resolution and accuracy and instead, the SailBuoy seems to be a very convenient instrument to track river plumes. In this presentation we describe the collected data and include comparisons with high resolution ocean model outputs. We also present further plans for SailBuoy campaigns.
Buoy observation for typhoon in southeast of Taiwan during summers of 2015 and 2016
NASA Astrophysics Data System (ADS)
Hsieh, C. Y.; Yang, Y. J.; Chang, M. H.; Chang, H. I.; Jan, S.; Wei, C. L.
2016-12-01
The western North Pacific is the most active area for the typhoon in the world, and typhoon caused disasters in this area. The marine observations are very important for the typhoon prediction. National Taiwan University (NTU) was developed a real-time data buoy system for typhoon observation. This buoy not only collected meteorological data, but also measured the temperature and salinity profiles of ocean's upper 500 m. The buoys, NTU1 and NTU2, were moored about 375 km and 175 km, respectively, from the southernmost tip of Taiwan. In summer of 2015, NTU1 buoy equipped with temperature and humidity probes, wind sensor, pyranometer, barometer, conductivity-temperature-depth (CTD) recorders, and temperature-pressure recorders. In summer of 2016, NTU1 and NTU2 buoys installed more instruments, such as rain gauge, net radiometer, and current meter, etc. During the observation period, there were three typhoons (Chan-hom, Soudler, and Goni) in 2015 and one typhoon (Nepartak) in 2016 approached buoy. Goni passed south and west side of NTU1 and the air pressure dropped around 25 hPa. Nepartak passed north side of NTU1 and south side of NTU2. The minimum distance between center of typhoon and NTU1 and NTU2 were about 11.48 km and 4.85 km, respectively. The NTU2 buoy recorded a maximum wind gust of 44 m/s, thickness of mixed layer increased to 120 m, and sea-surface temperature dropped 3 °C. In addition, the typhoon induced the near inertial internal motion for a couple of days. Applied the in-situ data to derive the net heat flux and its variations were from 600 W/m2 to -1000W/m2 during typhoon period. It indicate that the ocean provide energy to typhoon around this area. Moreover, the sum of sensible and latent heat flux calculated from observation data was 4.5 times than satellite-based products.
Sharma, Neha; D'Sa, Eurico
2008-03-18
The northern Gulf of Mexico is a region that has been frequently impacted in recent years by natural disasters such as hurricanes. The use of remote sensing data such as winds from NASA's QuikSCAT satellite sensor would be useful for emergency preparedness during such events. In this study, the performance of QuikSCAT products, including JPL's latest Level 2B (L2B) 12.5 km swath winds, were evaluated with respect to buoy-measured winds in the Gulf of Mexico for the period January 2005 to February 2007. Regression analyses indicated better accuracy of QuikSCAT's L2B DIRTH, 12.5 km than the Level 3 (L3), 25 km wind product. QuikSCAT wind data were compared directly with buoy data keeping a maximum time interval of 20 min and spatial interval of 0.1° (≈10 km). R² values for moderate wind speeds were 0.88 and 0.93 for L2B, and 0.75 and 0.89 for L3 for speed and direction, respectively. QuikSCAT wind comparisons for buoys located offshore were better than those located near the coast. Hurricanes that took place during 2002-06 were studied individually to obtain regressions of QuikSCAT versus buoys for those events. Results show QuikSCAT's L2B DIRTH wind product compared well with buoys during hurricanes up to the limit of buoy measurements. Comparisons with the National Hurricane Center (NHC) best track analyses indicated QuikSCAT winds to be lower than those obtained by NHC, possibly due to rain contamination, while buoy measurements appeared to be constrained at high wind speeds. This study has confirmed good agreement of the new QuikSCAT L2B product with buoy measurements and further suggests its potential use during extreme weather conditions in the Gulf of Mexico.
Typhoon generated surface gravity waves measured by NOMAD-type buoys
NASA Astrophysics Data System (ADS)
Collins, Clarence O., III
This study examines wind-generated ocean surface waves as measured by NOMAD-type buoys during the ONR-sponsored Impact of Typhoons on the Ocean in the Pacific (ITOP) field experiment in 2010. 1-D measurements from two new Extreme Air-Sea Interaction (EASI) NOMAD-type buoys were validated against measurements from established Air-Sea Interaction Spar (ASIS) buoys. Also, during ITOP, 3 drifting Miniature Wave Buoys, a wave measuring marine radar on the R/V Roger Revelle, and several overpasses of JASON-1 (C- and Ku-band) and -2 (Ku-band) satellite altimeters were within 100 km of either EASI buoy. These additional measurements were compared against both EASI buoys. Findings are in line with previous wave parameter inter-comparisons. A corroborated measurement of mean wave direction and direction at the peak of the spectrum from the EASI buoy is presented. Consequently, this study is the first published account of directional wave information which has been successfully gathered from a buoy with a 6 m NOMAD-type hull. This result may be applied to improve operational coverage of wave direction. In addition, details for giving a consistent estimate of sea surface elevation from buoys using strapped down accelerometers are given. This was found to be particularly important for accurate measurement of extreme waves. These technical studies established a high level of confidence in the ITOP wave measurements. Detailed frequency-direction spectra were analyzed. Structures in the wave field were described during the close passages of 4 major tropical cyclones (TC) including: severe tropical storm Dianmu, Typhoon Fanapi, Super Typhoon Megi, and Typhoon Chaba. In addition, significant swell was measured from a distant 5th TC, Typhoon Malakas. Changes in storm direction and intensity are found to have a profound impact on the wave field. Measurements of extreme waves were explored. More extreme waves were measured during TCs which coincided with times of increased wave steepness. The largest extreme waves, which are more impressive than the Draupner (aka Newyears) wave in terms of normalized wave height, were found to occur under circumstances which support the theory of modulation instability. It is suggested that swell and wind sea, as generated by complex TCs winds, may merge and/or couple in such a way to produce sea-states which are unstable. The largest extreme wave, which was over 21 m high, appears to have occurred under such circumstances. However, the development of unstable seas, and the possible connection between the occurrence of extreme waves and unstable seas, has yet to be confirmed.
Numerical Modeling of Coastal Dredged Material Placement Study at Noyo Harbor, CA
2013-07-01
Information Program ( CDIP , http://cdip.ucsd.edu) Buoy 46213. NDBC Buoy 46014, located offshore Noyo Bay, collects non- directional wave spectral data...lists these NDBC, CDIP , and NOAA stations and their location information. Fig. 5: Monthly mean wave height at Buoys 46014, 46022, and 46213...primarily sand with small percentages of mixed gravel, silt and clay (Table 2). Table 1. NDBC, CDIP , and NOAA station locations Station Latitude
Worldwide Buoy Technology Survey. Volume 2. Appendix B. Buoy Records. Book 2. Germany - USA
1991-02-01
arrangement and effectiveness of the complete system could not be addressed in detail within the constraints of this project. In an overall evaluation of...the SRA system , such considerations should also be addressed. The USCG’s Waterway Analysis and Management System (WAMS) is considering this matter as...project. The task includes the screening of worldwide engineering and technical information on buoy systems , approaches to problem solving (particularly
US program in anchored data buoy and the other fixed observation platforms
NASA Astrophysics Data System (ADS)
McCall, J. C.
The NOAA Data Buoy Office (NOBO) develops and operates moored buoys in all U.S. coastal and offshore waters from New England to Hawaii (including the Great Lakes) to provide real-time environmental measurements in data-sparse areas for the National Weather Service and other public and private users. The NOBO also has a program for development, deployment, and operation of drifting buoys, which provide environmental measurements in the South Atlantic and Pacific from Chili to Australia and in the Northern Hemisphere. In addition, NOBO develops, deploys, and operates special purpose environmental measuring systems for other government agencies, particularly for petroleum-related purposes, and has an engineering development effort in procuring new and improved sensor and communications systems.
Circumpolar Biodiversity Monitoring Programme coastal biodiversity monitoring background paper
McLennan, Donald; Anderson, Rebecca D.; Wegeberg, S.; Pettersvik Arvnes, Maria; Sergienko, Liudmila; Behe, Carolina; Moss-Davies, Pitseolak; Fritz, S.; Markon, Carl J.; Christensen, T.; Barry, T.; Price, C.
2016-01-01
In 2014, the United States (U.S.) and Canada agreed to act as co-lead countries for the initial development of the Coastal Expert Monitoring Group (CEMG) as part of the Circumpolar Biodiversity Monitoring Program (CBMP, www. cbmp.is) under the Arctic Council’s Conservation of Arctic Flora and Fauna (CAFF, www.caff.is) working group. The CAFF Management Board approved Terms of Reference for the CEMG in the spring of 2014. The primary goal of the CEMG is to develop a long term, integrated, multi-disciplinary, circumpolar Arctic Coastal Biodiversity Monitoring Plan (the Coastal Plan) that relies on science and Traditional Knowledge, and has direct and relevant application for communities, industry, government decision makers, and other users. In addition to the monitoring plan, the CAFF working group has asked the CBMP, and thus the CEMG, to develop an implementation plan that identifies timeline, costs, organizational structure and partners. This background paper provides a platform for the guidance for the development of the Coastal Plan and is produced by the CEMG with assistance from a number of experts in multiple countries.
Role of rafting in the mechanical redistribution of sea ice thickness
NASA Astrophysics Data System (ADS)
Babko, O.; Rothrock, D. A.; Maykut, G. A.
2002-08-01
Ice draft data derived from upward looking sonar observations collected during a Scientific Ice Expeditions (SCICEX) submarine cruise in the Arctic Ocean have been used to test the ice thickness distribution theory of Thorndike et al. [1975]. Two separate ice draft surveys, 40 days apart, were made during the fall of 1996 in a circular Lagrangian region ~180 km across. Air temperature and deformation data from buoys in the region were used to force an ice thickness distribution model in an effort to reproduce the changes observed over the 40 day interval. Initial tests with an elementary ridging treatment were unsuccessful in predicting the observed change in the ice thickness distribution. The shape of the distribution suggested that both ridging and rafting of ice were involved in the redistribution process. Modifying the theory to include rafting along with ridging resulted in much improved agreement between the modeled and observed ice thickness distributions. This result, taken together with many other field observations, leads us to believe that rafting is an important component of the mechanical redistribution of ice thickness during the fall.
NASA Technical Reports Server (NTRS)
Kwok, Ronald
2008-01-01
We demonstrate that sea ice motion in summer can be derived reliably from the 18GHz channel of the AMSR-E instrument on the EOS Aqua platform. The improved spatial resolution of this channel with its lower sensitivity to atmospheric moisture seems to have alleviated various issues that have plagued summer motion retrievals from shorter wavelength observations. Two spatial filters improve retrieval quality: one reduces some of the microwave signatures associated with synoptic-scale weather systems and the other removes outliers. Compared with daily buoy drifts, uncertainties in motion are approx.3-4 km/day. Using the daily motion fields, we examine five years of summer ice area exchange between the Pacific and Atlantic sectors of the Arctic Ocean. With the sea-level pressure patterns during the summer of 2006 and 2007 favoring the export of sea ice into the Atlantic Sector, the regional outflow is approx.21% and approx.15% of the total sea ice retreat in the Pacific sector.
NASA Astrophysics Data System (ADS)
Crosby, S. C.; O'Reilly, W. C.; Guza, R. T.
2016-02-01
Accurate, unbiased, high-resolution (in space and time) nearshore wave predictions are needed to drive models of beach erosion, coastal flooding, and alongshore transport of sediment, biota and pollutants. On highly sheltered shorelines, wave predictions are sensitive to the directions of onshore propagating waves, and nearshore model prediction error is often dominated by uncertainty in offshore boundary conditions. Offshore islands and shoals, and coastline curvature, create complex sheltering patterns over the 250km span of southern California (SC) shoreline. Here, regional wave model skill in SC was compared for different offshore boundary conditions created using offshore buoy observations and global wave model hindcasts (National Oceanographic and Atmospheric Administration Wave Watch 3, WW3). Spectral ray-tracing methods were used to transform incident offshore swell (0.04-0.09Hz) energy at high directional resolution (1-deg). Model skill is assessed for predictions (wave height, direction, and alongshore radiation stress) at 16 nearshore buoy sites between 2000 and 2009. Model skill using buoy-derived boundary conditions is higher than with WW3-derived boundary conditions. Buoy-driven nearshore model results are similar with various assumptions about the true offshore directional distribution (maximum entropy, Bayesian direct, and 2nd derivative smoothness). Two methods combining offshore buoy observations with WW3 predictions in the offshore boundary condition did not improve nearshore skill above buoy-only methods. A case example at Oceanside harbor shows strong sensitivity of alongshore sediment transport predictions to different offshore boundary conditions. Despite this uncertainty in alongshore transport magnitude, alongshore gradients in transport (e.g. the location of model accretion and erosion zones) are determined by the local bathymetry, and are similar for all predictions.
New buoy observation system for tsunami and crustal deformation
NASA Astrophysics Data System (ADS)
Takahashi, Narumi; Ishihara, Yasuhisa; Ochi, Hiroshi; Fukuda, Tatsuya; Tahara, Jun'ichiro; Maeda, Yosaku; Kido, Motoyuki; Ohta, Yusaku; Mutoh, Katsuhiko; Hashimoto, Gosei; Kogure, Satoshi; Kaneda, Yoshiyuki
2014-09-01
We have developed a new system for real-time observation of tsunamis and crustal deformation using a seafloor pressure sensor, an array of seafloor transponders and a Precise Point Positioning (PPP ) system on a buoy. The seafloor pressure sensor and the PPP system detect tsunamis, and the pressure sensor and the transponder array measure crustal deformation. The system is designed to be capable of detecting tsunami and vertical crustal deformation of ±8 m with a resolution of less than 5 mm. A noteworthy innovation in our system is its resistance to disturbance by strong ocean currents. Seismogenic zones near Japan lie in areas of strong currents like the Kuroshio, which reaches speeds of approximately 5.5 kt (2.8 m/s) around the Nankai Trough. Our techniques include slack mooring and new acoustic transmission methods using double pulses for sending tsunami data. The slack ratio can be specified for the environment of the deployment location. We can adjust slack ratios, rope lengths, anchor weights and buoy sizes to control the ability of the buoy system to maintain freeboard. The measured pressure data is converted to time difference of a double pulse and this simple method is effective to save battery to transmit data. The time difference of the double pulse has error due to move of the buoy and fluctuation of the seawater environment. We set a wire-end station 1,000 m beneath the buoy to minimize the error. The crustal deformation data is measured by acoustic ranging between the buoy and six transponders on the seafloor. All pressure and crustal deformation data are sent to land station in real-time using iridium communication.
System Identification and Control of a Joint-Actuated Buoy
2014-05-09
14 Figure 9: Green and Orange Colored Stripes of Craft Foam on the Buoy Payload ........... 15 Figure 10: Buoy Step...circuit board. The copper and blue paper were then heated in a press-n-peel press for just over one minute to allow the printer toner to bond with the...equidistant to each other running along the length of the payload, as shown in Figure 9. Figure 9: Green and Orange Colored Stripes of Craft Foam
1990-09-01
expanded in a specific direction if movement is indicated. Controlled dumping at precise coordinates or at marker buoys may reduce the required survey area...of the meters or theft of the marker buoys. Subsurface markers using acoustic releases prevent vandalism and loss of marker buoys, but they...data from field studies such as impact investigations ’Underwood 1981; Heck and Horowitz 1984; Hurlbert 1984; Millard and Lettenmaier 1986; Stewart
Estimation of excitation forces for wave energy converters control using pressure measurements
NASA Astrophysics Data System (ADS)
Abdelkhalik, O.; Zou, S.; Robinett, R.; Bacelli, G.; Wilson, D.
2017-08-01
Most control algorithms of wave energy converters require prediction of wave elevation or excitation force for a short future horizon, to compute the control in an optimal sense. This paper presents an approach that requires the estimation of the excitation force and its derivatives at present time with no need for prediction. An extended Kalman filter is implemented to estimate the excitation force. The measurements in this approach are selected to be the pressures at discrete points on the buoy surface, in addition to the buoy heave position. The pressures on the buoy surface are more directly related to the excitation force on the buoy as opposed to wave elevation in front of the buoy. These pressure measurements are also more accurate and easier to obtain. A singular arc control is implemented to compute the steady-state control using the estimated excitation force. The estimated excitation force is expressed in the Laplace domain and substituted in the control, before the latter is transformed to the time domain. Numerical simulations are presented for a Bretschneider wave case study.
NASA Technical Reports Server (NTRS)
Massom, Robert A.
1992-01-01
Data from four buoys tracked by Nimbus 6 and concurrent ice concentrations retrieved from Nimbus 7 scanning multichannel microwave radiometer data are used to investigate the progress and behavior of an area of sea ice as it drifts from the southwestern Weddell Sea. The overall drift characteristics and their relationship to ice edge displacement are examined within the framework of four zones. Three phases are identified in the large-scale behavior of the Weddell Sea ice cover, namely, a rapid equatorward and eastward advance, a quasi-equilibrium phase, and a period of rapid recession. Outbreaks of cold continental air alternate with incursions of relatively warm air from the north; warm conditions are recorded as far as 1200 km in from the ice edge in winter. Closed loops in the buoy trajectories, which are clockwise to the south of 63 deg S, reverse to become anticlockwise to the north. A coherence is observed in the response of the buoys to the passage of storms, even though the buoys separated by a distance of over 100 km.
Arctic Planning Scenarios: Scenario #2 - Safety and Security Scenario
2011-07-01
the case within the security communities (DND, RCMP and CBSA) where the facility expansion programme fell behind the pace of socio -economic growth...became a political issue with many First Nations leaders protesting about the speed of progress not keeping pace with the socio -economic demands of...raised level of socio -political consciousness quickly gravitated across the Inuit bands of NWT and Nunavut. It also drew support from those Southern
NASA Technical Reports Server (NTRS)
Johnson, R. E.
1975-01-01
Surface buoy/subsurface drogue drag coupling was investigated. Data acquisition methods and techniques derived from several experimental cruises on the Chesapeake Bay are presented. Four buoys were utilized: three coupled to steel plates rigidly attached to each other at right angles and at various depths; and one spar type that did not require drag plates. Data from these surface floats and the drogue depth combinations were processed. Errors in tracking the surface buoys are discussed.
A Steady State and Dynamic Analysis of a Mooring System.
1977-03-25
drag on subsurface buoy Dx«, »y«» Dzs Cable drag eoaponants in esble coordinates *A Distance between calculated location and actual loca- tion of...ship Be Modulus of elasticity of esble fh Highest natural frequency of systea 0 Horizontal distance between snshor and ship -- MUIIM—laSHS...TQD Tension in esble fron ahlp st subsurface buoy TBB Tension in cable fron anchor at aubaurfaea buoy Ty" Tension In n’th esble segaent Hif|l
Telemetry link for an automatic salmon migration monitor
NASA Technical Reports Server (NTRS)
Baldwin, H. A.; Freyman, R. W.
1973-01-01
The antenna and transmitter described in this report were designed for integration into the remote acoustic assessment system for detection of sockeye salmon in the Bristol Bay region of the Bering Sea. The assessment system configuration consists of an upward directed sonar buoy anchored 150 ft below the surface and attached by cable to a spar buoy tethered some 300 ft laterally. The spar buoy contains a telemetry transmitter, power supply, data processing electronics, an antenna and a beacon light.
Oil Slick Characterization Using Synthetic Aperture Radar
NASA Astrophysics Data System (ADS)
Jones, C. E.; Breivik, O.; Brekke, C.; Skrunes, S.; Holt, B.
2015-12-01
Oil spills are a hazard worldwide with potential of causing high impact disasters, and require an active oil spill response capability to protect personnel, the ecosystem, and the energy supply. As the amount of oil in traditionally accessible reserves decline, there will be increasing oil extraction from the Arctic and deep-water wells, both new sources with high risk and high cost for monitoring and response. Although radar has long been used for mapping the spatial extent of oil slicks, it is only since the Deepwater Horizon spill that synthetic aperture radar (SAR) has been shown capable of characterizing oil properties within a slick, and therefore useful for directing response to the recoverable thicker slicks or emulsions. Here we discuss a 2015 Norwegian oil-on-water spill experiment in which emulsions of known quantity and water-to-oil ratio along with a look-alike slick of plant oil were released in the North Sea and imaged with polarimetric SAR (PolSAR) by NASA's UAVSAR instrument for several hours following release. During the experiment, extensive in situ measurements were made from ship or aircraft with meteorological instruments, released drift buoys, and optical/IR imagers. The experiment was designed to provide validation data for development of a physical model relating polarization-dependent electromagnetic scattering to the dielectric properties of oil mixed with ocean water, which is the basis for oil characterization with SAR. Data were acquired with X-, C-, and L-band satellite-based SARs to enable multi-frequency comparison of characterization capabilities. In addition, the data are used to develop methods to differentiate mineral slicks from biogenic look-alikes, and to better understand slick weathering and dispersion. The results will provide a basis for modeling oil-in-ice spills, currently a high priority for nations involved in Arctic oil exploration. Here we discuss the Norwegian experiment, the validation data, and the results of analysis of the SAR data acquired during the experiment. This work was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. The Norwegian experiment was partly financed by CIRFA - Centre for integrated remote sensing and forecasting for arctic operations.
Klopov, V; Odland, J O; Burkow, I C
1998-10-01
Under the auspices of Arctic Monitoring and Assessment Programme (AMAP), a Russian-Norwegian co-operation project was established to assess the exposure of delivering women to persistent organic pollutants (POPs) in Arctic areas of Russia. In the period 1993-95 blood and breast milk samples were collected from 94 delivering women in Yamal and Tajmyr Autonomous Regions of Siberia. Concentrations of chlorinated pesticides and polychlorinated biphenyls (PCBs) were determined by high resolution gas chromatography with electron capture detection. The POP levels in maternal plasma among the non-indigenous women were higher than the native population, especially in total PCB, HCHs (hexachlorocyclohexanes) and the DDT-group. The dietary questionnaires showed that the non-indigenous populations consumed considerably less local food items like reindeer meat and fresh water fish. There was no correlation between local food consumption and elevated levels of pollutants. Even if the indigenous groups had lower concentrations of the most important pollutants than the non-indigenous population, they were still higher than the levels measured in the Scandinavian countries of the AMAP-study and up to levels of medical concern. The most important sources of organic pollutants for the Russian Arctic populations of Yamal and Tajmyr seems to be imported food from other areas of Russia and local use of pesticides. It must be a high priority concern to further elucidate these trends and initiate prophylactic measures for the exposed population groups.
NASA Astrophysics Data System (ADS)
di Sarra, Alcide; Bommarito, Carlo; Anello, Fabrizio; Di Iorio, Tatiana; Meloni, Daniela; Monteleone, Francesco; Pace, Giandomenico; Piacentino, Salvatore; Sferlazzo, Damiano
2017-04-01
An oceanographic buoy has been developed and deployed in August 2015 about 3.3 miles South West of the island of Lampedusa, at 35.49°N, 12.47°E, in the central Mediterranean Sea. The buoy was developed within the Italian RITMARE flagship project, and contributes to the Italian fixed-point oceanographic observation network. The buoy is an elastic beacon type and is intended to study air-sea interactions, propagation of radiation underwater, and oceanographic properties. The buoy measurements complement the atmospheric observations carried out at the long-term Station for Climate Observations on the island of Lampedusa (www.lampedusa.enea.it; 35.52°N, 12.63°E), which is located about 15 km E-NE of the buoy. Underwater instruments and part of the atmospheric sensors are presently being installed on the buoy. Measurements of downwelling shortwave, SW, and longwave, LW, irradiance, have been made since September 2015 with a Kipp and Zonen CMP21 pyranometer and a Kipp and Zonen CGR4 pyrgeometer, respectively. The radiometers are mounted on a small platform at about 7 m above sea level, on an arm protruding southward of the buoy. High time resolution data, at 1 Hz, have been acquired since December 2015, together with the sensors' attitude. Data from the period December 2015-December 2016 are analyzed and compared with measurements made on land at the Station for Climate Observations at 50 m above mean sea level. This study aims at deriving high quality determinations of the downwelling radiation over sea in the central Mediterranean. The following aspects will be discussed: - representativeness of time averaging of irradiance measurements over moving platforms; - comparison of downwelling irradiance measurements made over land and over ocean, and identification of possible correction strategies to infer irradiances over the ocean from close by measurements made over land; - influence of dome cleaning on the quality of measurements; - envisaging possible corrections strategies for varying radiometers' attitude.
NASA Astrophysics Data System (ADS)
Roggenstein, E. B.; Hensley, W.
2011-12-01
Over the past two hundred years, water level observations in coastal areas have been used to help mariners navigate oceans and estuaries, cartographers develop nautical charts, government agencies regulate boundaries, and scientists gain a better understanding of various physical processes in the ocean. As technology has progressed the latency in providing these data to the user has been reduced. The National Oceanic and Atmospheric Administration's (NOAA) Center for Operational Oceanographic Products and Services (CO-OPS) provides near real-time oceanographic and meteorological data to support navigation, coastal managers, and storm surge and tsunami warning programs. CO-OPS maintains the National Water Level Observation Network (NWLON), a system of over 200 stations for the coastal United States, Great Lakes, Caribbean islands, and Pacific island territories. CO-OPS also supports the NOAA Physical Oceanographic Real Time Systems° (PORTS), which are currently operating in 21 US ports. With an expanding role in Arctic and Alaska support, CO-OPS has identified a need for a robust and reliable data communications pathway to supplement the existing Geostationary Operational Environmental Systems (GOES) network, which has limitations at high latitudes. Iridium satellite Short Burst Data (SBD) services offer a global coverage, including remote Arctic regions outside of GOES coverage. Previous testing conducted by CO-OPS has shown a great potential for the SBD service including continuous near-real-time 6 minute data transmissions from two CO-OPS test water level stations located in Guam, with >99.9% data return. Also, successful transmissions of hourly wave statistics were demonstrated with a with a test system that employed a Nortek Acoustic Wave and Current (AWAC) instrument in Chesapeake Bay were accomplished. Data transmissions involved a buoy-mounted SIM-less SBD modem. Independent of location, data can be transmitted from a remote instrument platform to Iridium satellites with a latency of just 15 seconds. Successful test demonstrations have led to discussions regarding prospective work to integrate these small modems into CO-OPS current meters that are mounted on United States Coast Guard (USCG) Aid to Navigation (ATON) buoys, improving the reliability of the real-time transmission pathway between data collection and data reporting via PORTS °. Overall, this work has shown that with careful evaluation of data needs, commercial Iridium service can be economically used to accomplish telemetry requirements. It also shows potential for event-driven high frequency data transmission options, for applications such as marine warning systems. CO-OPS efforts to test and evaluate Iridium communications oceanographic observatories reported on here has been a collaborative endeavor with the United States Army Corp Engineers (USACE) Field Research Facility (FRF) in Duck, NC, the USACE Cold Regions Research Engineering Laboratory (CRREL) in Hanover, NH, NAL Research Inc, Sutron Corporation,and Nortek USA.
An improvement of the GPS buoy system for detecting tsunami at far offshore
NASA Astrophysics Data System (ADS)
Kato, T.; Terada, Y.; Nagai, T.; Kawaguchi, K.; Koshimura, S.; Matsushita, Y.
2012-12-01
We have developed a GPS buoy system for detecting a tsunami before its arrival at coasts and thereby mitigating tsunami disaster. The system was first deployed in 1997 for a short period in the Sagami bay, south of Tokyo, for basic experiments, and then deployed off Ofunato city, northeastern part of Japan, for the period 2001-2004. The system was then established at about 13km south of Cape Muroto, southwestern part of Japan, since 2004. Five tsunamis of about 10cm have been observed in these systems, including 2001 Peru earthquake (Mw8.3), 2003 Tokachi-oki earthquake (Mw8.3), 2004 Off Kii Peninsula earthquake (Mw7.4), 2010 Chile earthquake (Mw8.8), and 2011 Tohoku-Oki earthquake (Mw9.0). These experiments clearly showed that GPS buoy is capable of detecting tsunami with a few centimeter accuracy and can be monitored in near real time by applying an appropriate filter, real-time data transmission using radio and dissemination of obtained records of sea surface height changes through internet. Considering that the system is a powerful tool to monitor sea surface variations due to wind as well as tsunami, the Ministry of Land, Infrastructure, Transport and Tourism implemented the system in a part of the Nationwide Ocean Wave information network for Ports and HArbourS (NOWPHAS) system and deployed the system at 15 sites along the coasts around the Japanese Islands. The system detected the tsunami due to the 11th March 2011 Tohoku-Oki earthquake with higher than 6m of tsunami height at the site Off South Iwate (Kamaishi). The Japan Meteorological Agency that was monitoring the record updated the level of the tsunami warning to the greatest value due to the result. Currently, the GPS buoy system uses a RTK-GPS which requires a land base for obtaining precise location of the buoy by a baseline analysis. This algorithm limits the distance of the buoy to, at most, 20km from the coast as the accuracy of positioning gets much worse as the baseline distance becomes longer than 20km. This limits the lead time for letting coastal residents to evacuate from the coast only about 10 minutes after the detection of tsunami at a GPS buoy. This requires us to improve the system to put the buoy much farther from the coast. In order to solve this problem, we have introduced a new algorithm of precise point positioning with ambiguity resolution (PPP-AR) method and point precise variance detection (PVD) method for estimating the precise location of the buoy. As these method does not require land base station, it may allow us to deploy a buoy much farther than 100km offshore observation. Also, an open source program package (RTKLIB) is introduced for kinematic analysis for a long baseline. A new experiment using this system has started about 40km south off Cape Muroto in April 2012. One of buoys called as "Kuroshio Bokujo", which is used as a fish bed by Kochi Prefecture, is used for this purpose. The positioning results are exhibited in real time on the internet.
46 CFR 160.050-4 - Construction and workmanship.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Plastic § 160.050-4 Construction and workmanship. (a) General. This specification covers ring life buoys... the buoy with a suitable waterproof adhesive which is compatible with the unicellular plastic used in...
NASA Technical Reports Server (NTRS)
Chapman, W. S.; Yen, H. H.
1974-01-01
As a result of a consortium of several industries and organizations, an economical, versatile, and stable data collection and transmission buoy has been designed, developed, and deployed to gather and transmit water quality data to a ground receiving station at three-minute intervals and to the earth resources technology satellite (ERTS) as it passes over the deployed buoy every 12 hours. The buoy system, designed for both fresh and salt water application, gathers data inclusive of temperature measurement, conductivity, relative acidity, dissolved oxygen, current speed, and direction. The mechanical design philosophy used to determine and satisfy boundary conditions involving stability, ease of deployment, servicing and maintenance, minimal manufacturing costs, and fresh and salt water installation capability is discussed. The development of peripheral handling equipment and anchoring systems is described.
Ridging and strength in modeling the thickness distribution of Arctic sea ice
NASA Astrophysics Data System (ADS)
Flato, Gregory M.; Hibler, William D.
1995-09-01
A theory describing evolution of the ice thickness distribution (the probability density of ice thickness) was proposed by Thorndike et al. (1975) and has been used in several sea ice models. The advantage of this theory over the widely used two-level formulation is that it treats ridging explicitly as a redistribution of ice thickness, and ice strength as a function of energy losses incurred by ridge formation. However, the parameterization of these processes remains rather speculative and largely untested, and so our purpose here is to explore these parameterizations using a numerical model based on this theory. The model uses a 160-km resolution grid of the Arctic and 7 years of observed atmospheric forcing data (1979-1985). Monthly oceanic heat flux and current fields are obtained from a 40-km resolution coupled ice-ocean model run separately with the same forcing. By requiring the computed monthly mean ice drift to have the same magnitude as observed buoy drift, we estimate the primary strength parameter: the ratio of total to potential energy change during ridging. This ratio depends on the value of other parameters; however, the standard case has a ratio of 17 which is within the range estimated by Hopkins (1994) in simulations of individual ridging events. The effects of ridge redistribution and shear ridging parameters are illustrated by a series of sensitivity studies and comparisons between observed and modeled ice thickness distributions and ridge statistics. In addition, these comparisons highlight the following shortcomings of the thickness distribution theory as it is presently implemented: first, the process of first-year to multiyear ridge consolidation is ignored; and second, the observed preferential melt of thick ridged ice is not reproduced.
NASA Technical Reports Server (NTRS)
Nghiem, S. V.; Clemente-Colon, P.; Rigor, I. G.; Hall, D. K.; Neumann, G.
2011-01-01
The seafloor has a profound role in Arctic sea ice formation and seasonal evolution. Ocean bathymetry controls the distribution and mixing of warm and cold waters, which may originate from different sources, thereby dictating the pattern of sea ice on the ocean surface. Sea ice dynamics, forced by surface winds, are also guided by seafloor features in preferential directions. Here, satellite mapping of sea ice together with buoy measurements are used to reveal the bathymetric control on sea ice growth and dynamics. Bathymetric effects on sea ice formation are clearly observed in the conformation between sea ice patterns and bathymetric characteristics in the peripheral seas. Beyond local features, bathymetric control appears over extensive ice-prone regions across the Arctic Ocean. The large-scale conformation between bathymetry and patterns of different synoptic sea ice classes, including seasonal and perennial sea ice, is identified. An implication of the bathymetric influence is that the maximum extent of the total sea ice cover is relatively stable, as observed by scatterometer data in the decade of the 2000s, while the minimum ice extent has decreased drastically. Because of the geologic control, the sea ice cover can expand only as far as it reaches the seashore, the continental shelf break, or other pronounced bathymetric features in the peripheral seas. Since the seafloor does not change significantly for decades or centuries, sea ice patterns can be recurrent around certain bathymetric features, which, once identified, may help improve short-term forecast and seasonal outlook of the sea ice cover. Moreover, the seafloor can indirectly influence cloud cover by its control on sea ice distribution, which differentially modulates the latent heat flux through ice covered and open water areas.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeMott, P. J.; Hill, T. C.J.
Despite the significance of the marginal ice zones of the Arctic Ocean, basic parameters such as sea surface temperature (SST) and a range of sea-ice characteristics are still insufficiently understood in these areas, and especially so during the summer melt period. The field campaigns summarized here, identified collectively as the “Marginal Ice Zone Ocean and Ice Observations and Processes Experiment” (MIZOPEX), were funded by U.S. National Aeronautic and Space Administration (NASA) with the intent of helping to address these information gaps through a targeted, intensive observation field campaign that tested and exploited unique capabilities of multiple classes of unmanned aerialmore » systems (UASs). MIZOPEX was conceived and carried out in response to NASA’s request for research efforts that would address a key area of science while also helping to advance the application of UASs in a manner useful to NASA for assessing the relative merits of different UASs. To further exercise the potential of unmanned systems and to expand the science value of the effort, the field campaign added further challenges such as air deployment of miniaturized buoys and coordinating missions involving multiple aircraft. Specific research areas that MIZOPEX data were designed to address include relationships between ocean skin temperatures and subsurface temperatures and how these evolve over time in an Arctic environment during summer; variability in sea-ice conditions such as thickness, age, and albedo within the marginal ice zone (MIZ); interactions of SST, salinity, and ice conditions during the melt cycle; and validation of satellite-derived SST and ice concentration fields provided by satellite imagery and models.« less
Real-Time Seismic Data from the Bottom Sea
Roset, Xavier; Trullols, Enric; Artero-Delgado, Carola; Prat, Joana; Massana, Immaculada; Carbonell, Montserrat; Barco de la Torre, Jaime; Toma, Daniel Mihai
2018-01-01
An anchored marine seismometer, acquiring real-time seismic data, has been built and tested. The system consists of an underwater seismometer, a surface buoy, and a mooring line that connects them. Inductive communication through the mooring line provides an inexpensive, reliable, and flexible solution. Prior to the deployment the dynamics of the system have been simulated numerically in order to find optimal materials, cables, buoys, and connections under critical marine conditions. The seismometer used is a high sensitivity triaxial broadband geophone able to measure low vibrational signals produced by the underwater seismic events. The power to operate the surface buoy is provided by solar panels. Additional batteries are needed for the underwater unit. In this paper we also present the first results and an earthquake detection of a prototype system that demonstrates the feasibility of this concept. The seismometer transmits continuous data at a rate of 1000 bps to a controller equipped with a radio link in the surface buoy. A GPS receiver on the surface buoy has been configured to perform accurate timestamps on the seismic data, which makes it possible to integrate the seismic data from these marine seismometers into the existing seismic network. PMID:29642479
Real-Time Seismic Data from the Bottom Sea.
Roset, Xavier; Trullols, Enric; Artero-Delgado, Carola; Prat, Joana; Del Río, Joaquin; Massana, Immaculada; Carbonell, Montserrat; Barco de la Torre, Jaime; Toma, Daniel Mihai
2018-04-08
An anchored marine seismometer, acquiring real-time seismic data, has been built and tested. The system consists of an underwater seismometer, a surface buoy, and a mooring line that connects them. Inductive communication through the mooring line provides an inexpensive, reliable, and flexible solution. Prior to the deployment the dynamics of the system have been simulated numerically in order to find optimal materials, cables, buoys, and connections under critical marine conditions. The seismometer used is a high sensitivity triaxial broadband geophone able to measure low vibrational signals produced by the underwater seismic events. The power to operate the surface buoy is provided by solar panels. Additional batteries are needed for the underwater unit. In this paper we also present the first results and an earthquake detection of a prototype system that demonstrates the feasibility of this concept. The seismometer transmits continuous data at a rate of 1000 bps to a controller equipped with a radio link in the surface buoy. A GPS receiver on the surface buoy has been configured to perform accurate timestamps on the seismic data, which makes it possible to integrate the seismic data from these marine seismometers into the existing seismic network.
GPS water level measurements for Indonesia's Tsunami Early Warning System
NASA Astrophysics Data System (ADS)
Schöne, T.; Pandoe, W.; Mudita, I.; Roemer, S.; Illigner, J.; Zech, C.; Galas, R.
2011-03-01
On Boxing Day 2004, a severe tsunami was generated by a strong earthquake in Northern Sumatra causing a large number of casualties. At this time, neither an offshore buoy network was in place to measure tsunami waves, nor a system to disseminate tsunami warnings to local governmental entities. Since then, buoys have been developed by Indonesia and Germany, complemented by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART) buoys, and have been moored offshore Sumatra and Java. The suite of sensors for offshore tsunami detection in Indonesia has been advanced by adding GPS technology for water level measurements. The usage of GPS buoys in tsunami warning systems is a relatively new approach. The concept of the German Indonesian Tsunami Early Warning System (GITEWS) (Rudloff et al., 2009) combines GPS technology and ocean bottom pressure (OBP) measurements. Especially for near-field installations where the seismic noise may deteriorate the OBP data, GPS-derived sea level heights provide additional information. The GPS buoy technology is precise enough to detect medium to large tsunamis of amplitudes larger than 10 cm. The analysis presented here suggests that for about 68% of the time, tsunamis larger than 5 cm may be detectable.
A maximum power point tracking algorithm for buoy-rope-drum wave energy converters
NASA Astrophysics Data System (ADS)
Wang, J. Q.; Zhang, X. C.; Zhou, Y.; Cui, Z. C.; Zhu, L. S.
2016-08-01
The maximum power point tracking control is the key link to improve the energy conversion efficiency of wave energy converters (WEC). This paper presents a novel variable step size Perturb and Observe maximum power point tracking algorithm with a power classification standard for control of a buoy-rope-drum WEC. The algorithm and simulation model of the buoy-rope-drum WEC are presented in details, as well as simulation experiment results. The results show that the algorithm tracks the maximum power point of the WEC fast and accurately.
A Buoy for Continuous Monitoring of Suspended Sediment Dynamics
Mueller, Philip; Thoss, Heiko; Kaempf, Lucas; Güntner, Andreas
2013-01-01
Knowledge of Suspended Sediments Dynamics (SSD) across spatial scales is relevant for several fields of hydrology, such as eco-hydrological processes, the operation of hydrotechnical facilities and research on varved lake sediments as geoarchives. Understanding the connectivity of sediment flux between source areas in a catchment and sink areas in lakes or reservoirs is of primary importance to these fields. Lacustrine sediments may serve as a valuable expansion of instrumental hydrological records for flood frequencies and magnitudes, but depositional processes and detrital layer formation in lakes are not yet fully understood. This study presents a novel buoy system designed to continuously measure suspended sediment concentration and relevant boundary conditions at a high spatial and temporal resolution in surface water bodies. The buoy sensors continuously record turbidity as an indirect measure of suspended sediment concentrations, water temperature and electrical conductivity at up to nine different water depths. Acoustic Doppler current meters and profilers measure current velocities along a vertical profile from the water surface to the lake bottom. Meteorological sensors capture the atmospheric boundary conditions as main drivers of lake dynamics. It is the high spatial resolution of multi-point turbidity measurements, the dual-sensor velocity measurements and the temporally synchronous recording of all sensors along the water column that sets the system apart from existing buoy systems. Buoy data collected during a 4-month field campaign in Lake Mondsee demonstrate the potential and effectiveness of the system in monitoring suspended sediment dynamics. Observations were related to stratification and mixing processes in the lake and increased turbidity close to a catchment outlet during flood events. The rugged buoy design assures continuous operation in terms of stability, energy management and sensor logging throughout the study period. We conclude that the buoy is a suitable tool for continuous monitoring of suspended sediment concentrations and general dynamics in fresh water bodies. PMID:24129017
“Open Hatch” Tour of Offshore Wind Buoy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zayas, Jose
2015-09-18
Wind and Water Power Technologies Office Director, Jose Zayas gives a behind the scenes tour of the AXYS WindSentinel research buoy, which uses high-tech instruments to measure conditions for potential offshore wind energy development.
Storm wave buoy equipped with micromechanical inertial unit: Results of development and testing
NASA Astrophysics Data System (ADS)
Gryazin, D. G.; Staroselcev, L. P.; Belova, O. O.; Gleb, K. A.
2017-07-01
The article describes the results of developing a wave buoy to measure the statistical characteristics of waves and the characteristics of directional spectra of three-dimensional waves. The device is designed for long-term measurements lasting up to a season, which can help solve problems in forecasting waves and preventing emergencies from wave impact on offshore platforms, hydraulic structures, and other marine facilities. The measuring unit involves triads of micromechanical gyroscopes, accelerometers, and a three-component magnetometer. A description of the device, results of laboratory research of its characteristics, and bench and full-scale tests are offered. It is noted that to assess the performance characteristics, comparative tests of the Storm wave buoy were conducted with a standard string wave probe installed on an offshore platform. It is shown that the characteristics and capabilities of the wave buoy make it possible to oust foreign devices from the domestic market.
Outfall siting with dye-buoy remote sensing of coastal circulation
NASA Technical Reports Server (NTRS)
Munday, J. C., Jr.; Welch, C. S.; Gordon, H. H.
1978-01-01
A dye-buoy remote sensing technique has been applied to estuarine siting problems that involve fine-scale circulation. Small hard cakes of sodium fluorescein and polyvinyl alcohol, in anchored buoys and low-windage current followers, dissolve to produce dye marks resolvable in 1:60,000 scale color and color infrared imagery. Lagrangian current vectors are determined from sequential photo coverage. Careful buoy placement reveals surface currents and submergence near fronts and convergence zones. The technique has been used in siting two sewage outfalls in Hampton Roads, Virginia: In case one, the outfall region during flood tide gathered floating materials in a convergence zone, which then acted as a secondary source during ebb; for better dispersion during ebb, the proposed outfall site was moved further offshore. In case two, flow during late flood was found to divide, with one half passing over shellfish beds; the proposed outfall site was consequently moved to keep effluent in the other half.
JEODI Workshop: Arctic site survey challenges
NASA Astrophysics Data System (ADS)
Jokat, W.; Backman, J.; Kristoffersen, Y.; Mikkelsen, N.; Thiede, J.
2003-04-01
In past decades the geoscientific activities in the High Arctic were rather low compared to other areas on the globe. The remoteness of the region and the difficult logistical conditions made Arctic research very expensive and the results unpredictable. In the late 80's this situation changed to the better since modern research icebreaker became available to the scientific community. These research platforms provided opportunities in terms of equipment, which was standard in other regions. Where necessary techniques were adapted allowing to conduct the experiments even in difficult ice conditions, e.g. multi-channel seismic. In the last decade the Arctic Ocean were identified to play a key role in our understanding of the Earth's climate. An urgent need for scientific deep drill holes in the central Arctic was obvious to better understand the climate evolution of the past in a regional and global sense. However, to select and prepare the drilling experiments sufficient site survey data, especially seismic data, are needed. These problems were addressed during a recent JEODI workshop in Copenhagen. The participants recommended dedicated expeditions tothe Alpha-Mendeleev Ridge, the Lomonosov Ridge and the Gakkel Ridge to provide a critical amount of geophysical data for future drilling efforts. An international expedition to the Alpha-Mendeleev Ridge was proposed as part of the International Geophysical Polar Year 2006/07 to investigate the least known oceanic ridge of the world's ocean. Besides scientific targets in the High Arctic it became obvious during the workshop that in the marginal seas and plateaux sufficient geophysical data exist to submit drilling proposals like for the Yermak Plateau, the Chukchi Plateau/Northwind Ridge and Laptew Sea continental margin. These proposals would perfectly complement the highly ranked drilling proposal on Lomonosov Ridge, which hopefully can be drilled in 2004 within the ODP/IODP programme. This presentation will provide information on the major results of this workshop as well as the planned activities in the next decade.
NASA Astrophysics Data System (ADS)
Kato, Teruyuki; Terada, Yukihiro; Nagai, Toshihiko; Koshimura, Shun'ichi
2010-05-01
We have developed a GPS buoy system for monitoring tsunami for over 12 years. The idea was that a buoy equipped with a GPS antenna and placed offshore may be an effective way of monitoring tsunami before its arrival to the coast and to give warning to the coastal residents. The key technology for the system is real-time kinematic (RTK) GPS technology. We have successfully developed the system; we have detected tsunamis of about 10cm in height for three large earthquakes, namely, the 23 June 2001 Peru earthquake (Mw8.4), the 26 September 2003 Tokachi earthquake (Mw8.3) and the 5 September 2004 earthquake (Mw7.4). The developed GPS buoy system is also capable of monitoring sea waves that are mainly caused by winds. Only the difference between tsunami and sea waves is their frequency range and can be segregated each other by a simple filtering technique. Given the success of GPS buoy experiments, the system has been adopted as a part of the Nationwide Ocean Wave information system for Port and HArborS (NOWPHAS) by the Ministry of Land, Infrastructure, Transport and Tourism of Japan. They have established more than eight GPS buoys along the Japanese coasts and the system has been operated by the Port and Airport Research Institute. As a future scope, we are now planning to implement some other additional facilities for the GPS buoy system. The first application is a so-called GPS/Acoustic system for monitoring ocean bottom crustal deformation. The system requires acoustic waves to detect ocean bottom reference position, which is the geometrical center of an array of transponders, by measuring distances between a position at the sea surface (vessel) and ocean bottom equipments to return the received sonic wave. The position of the vessel is measured using GPS. The system was first proposed by a research group at the Scripps Institution of Oceanography in early 1980's. The system was extensively developed by Japanese researchers and is now capable of detecting ocean bottom positions with a few centimeters in accuracy. The system is now operational for more than ten sites along the Japanese coasts. Currently, however, the measurements are not continuous but have been done once to several times a year using a boat. If a GPS and acoustic system is placed on a buoy, ocean bottom position could be monitored in near real-time and continuous manner. This will allow us to monitor more detailed and short term crustal deformations at the sea bottom. Another application plan is for an atmospheric research. Previous researchers have shown that GPS is capable of measuring atmospheric water vapor through estimating tropospheric zenith delay measurements of GPS at the sea surface. Information of water vapor content and its temporal variation over sea surface will much contribute to weather forecast on land which has mostly been conducted only by land observations. Considering that the atmospheric mass moves from west to east in general in and around Japanese islands, information of water vapor together with other atmospheric data from an array of GPS buoy placed in the west of Japanese Islands, will much improve weather forecast. We try to examine if this is also feasible. As a conclusion of a series of GPS buoy experiments, we could assert that GPS buoy system will be a powerful tool to monitor ocean surface and much contribute to provide safe and secure life of people.
Brentrup, Jennifer A.; Williamson, Craig E.; Colom-Montero, William; Eckert, Werner; de Eyto, Elvira; Grossart, Hans-Peter; Huot, Yannick; Isles, Peter D. F.; Knoll, Lesley B.; Leach, Taylor H.; McBride, Christopher G.; Pierson, Don; Pomati, Francesco; Read, Jordan S.; Rose, Kevin C.; Samal, Nihar R.; Staehr, Peter A.; Winslow, Luke A.
2016-01-01
The use of high-frequency sensors on profiling buoys to investigate physical, chemical, and biological processes in lakes is increasing rapidly. Profiling buoys with automated winches and sensors that collect high-frequency chlorophyll fluorescence (ChlF) profiles in 11 lakes in the Global Lake Ecological Observatory Network (GLEON) allowed the study of the vertical and temporal distribution of ChlF, including the formation of subsurface chlorophyll maxima (SSCM). The effectiveness of 3 methods for sampling phytoplankton distributions in lakes, including (1) manual profiles, (2) single-depth buoys, and (3) profiling buoys were assessed. High-frequency ChlF surface data and profiles were compared to predictions from the Plankton Ecology Group (PEG) model. The depth-integrated ChlF dynamics measured by the profiling buoy data revealed a greater complexity that neither conventional sampling nor the generalized PEG model captured. Conventional sampling techniques would have missed SSCM in 7 of 11 study lakes. Although surface-only ChlF data underestimated average water column ChlF, at times by nearly 2-fold in 4 of the lakes, overall there was a remarkable similarity between surface and mean water column data. Contrary to the PEG model’s proposed negligible role for physical control of phytoplankton during the growing season, thermal structure and light availability were closely associated with ChlF seasonal depth distribution. Thus, an extension of the PEG model is proposed, with a new conceptual framework that explicitly includes physical metrics to better predict SSCM formation in lakes and highlight when profiling buoys are especially informative.
Development of real-time mobile-buoy observation system for tsunami and crustal movement
NASA Astrophysics Data System (ADS)
Takahashi, N.; Ishihara, Y.; Fukuda, T.; Tahara, J.; Ochi, H.; Mori, T.; Deguchi, M.; Kido, M.; Ohta, Y.; Hino, R.; Mutoh, K.; Hashimoto, G.; Motohashi, O.; Kaneda, Y.
2014-12-01
We have developed real-time buoy system for tsunami and crustal movement since 2012. Our motivations are needs of the crustal movement data of not only for vertical component but horizontal, real-time data transmission for future prediction of the next large earthquake, and needs of relatively easily system comparing with the seafloor cable network system. Therefore, we are developing the above system using a buoy system, considering long term observation of approximately two years. Our system's characteristics are real-time observation, separation between tsunami and crustal movement, mobility, and environmental compatibility. Tsunami and crustal movement data are sent with intervals of an hour and a week respectively in real-time, and we can also get them on-demand via satellite transmission from the land station. We are going to observe tsunami using a pressure sensor and a PPP (precise point positioning) navigation system on the buoy, therefore, tsunami and vertical crustal deformation are separated in real-time. And the horizontal component of the crustal deformation is also measured by acoustic signals between the buoy and six seafloor transponders. Our system can be used under severe strong sea current with a speed of 5.5 knots due to adaption of slack mooring. Therefore, we can deploy it without consideration of sea current. In addition, the geometry including the size of the buoy, lengths of some ropes, and capacity of the electric battery and so on is tuned considering an environment of deployment location. Through twice sea trials, we are confirming each function. In this presentation, we introduce the outline and results of the sea trials.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-04
... to the point of origin. The restricted area will be marked by a lighted and signed floating buoy line... a signed floating buoy line without permission from the Supervisor of Shipbuilding, Conversion and...
COPERNICUS - The European Union Earth Observation Programme - State of play and way ahead
NASA Astrophysics Data System (ADS)
Koch, Astrid-Christina
2015-04-01
Copernicus is the new name of the European Earth Observation Programme, GMES (Global Monitoring for Environment and Security). Copernicus or rather its predecessor was established as an EU programme. It covers all the activities for ensuring an uninterrupted provision of accurate and reliable data and information on environmental issues and security matters to users in charge of policy making, implementation and monitoring, in the EU and its Member States. Copernicus aims at providing Europe with a continuous, independent and reliable access to observation data and information. The EU investment aims at filling the observation gaps, providing access to existing assets and developing operational services. The data policy of the Copernicus programme supports an open, full and free of charge data access that is in line with the data sharing principles of the Group for Earth Observation (GEO). Copernicus is structured in six Services: Marine, Atmosphere, Land and Climate change monitoring as well as support to Emergency and Security. Copernicus uses data from satellites and in-situ sensors such as buoys, balloons or air sensors to provide timely and reliable added-value information and forecasting to support for example, agriculture and fisheries, land use and urban planning, the fight against forest fires, disaster response, maritime transport or air pollution monitoring. The need for continuing such observations is becoming critical, considering the increasing political pressure on public authorities to take informed decisions in the field of environment, security and climate change and the need to respect international agreements. Copernicus also contributes to economic stability and growth by boosting commercial applications (the so-called downstream services) in many different sectors through a full and open access to Copernicus observation data and information products. KEY WORDS: Sentinels, big data, data access, Emergency, Marine, Atmosphere.
Shallow Water Optical Water Quality Buoy
NASA Technical Reports Server (NTRS)
Bostater, Charles
1998-01-01
This NASA grant was funded as a result of an unsolicited proposal submission to Kennedy Space Center. The proposal proposed the development and testing of a shallow water optical water quality buoy. The buoy is meant to work in shallow aquatic systems (ponds, rivers, lagoons, and semi-enclosed water areas where strong wind wave action is not a major environmental During the project period of three years, a demonstration of the buoy was conducted. The last demonstration during the project period was held in November, 1996 when the buoy was demonstrated as being totally operational with no tethered communications line. During the last year of the project the buoy was made to be solar operated by large gel cell batteries. Fund limitations did not permit the batteries in metal enclosures as hoped for higher wind conditions, however the system used to date has worked continuously for in- situ operation of over 18 months continuous deployment. The system needs to have maintenance and somewhat continuous operational attention since various components have limited lifetime ages. For example, within the last six months the onboard computer has had to be repaired as it did approximately 6 months after deployment. The spectrograph had to be repaired and costs for repairs was covered by KB Science since no ftmds were available for this purpose after the grant expired. Most recently the computer web page server failed and it is currently being repaired by KB Science. In addition, the cell phone operation is currently being ftmded by Dr. Bostater in order to maintain the system's operation. The above points need to be made to allow NASA to understand that like any sophisticated measuring system in a lab or in the field, necessary funding and maintenance is needed to insure the system's operational state and to obtain quality factor. The proposal stated that the project was based upon the integration of a proprietary and confidential sensor and probe design that was developed by KB Science and Engineering and is currently patented by KB Science. The buoy's purpose was to collected hyperspectral optical signatures for analysis and resulting estimation of water quality parameters such as chlorophyll-a, seston and dissolved organic matter (DOC). The ultimate goal of the project was to develop a buoy that would integrate a probe to measure upwelling light from a source and thus relate this backscattered light to water quality parameters.
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. ...
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. ...
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. ...
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. ...
âOpen Hatchâ Tour of Offshore Wind Buoy
Zayas, Jose
2018-01-16
Wind and Water Power Technologies Office Director, Jose Zayas gives a behind the scenes tour of the AXYS WindSentinel research buoy, which uses high-tech instruments to measure conditions for potential offshore wind energy development.
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. ...
The winds of the comparison data set for the Seasat Gulf of Alaska Experiment
NASA Technical Reports Server (NTRS)
Pierson, W. J.; Peteherych, S.; Wilkerson, J. C.
1980-01-01
Ship and data buoy winds used for comparison in the validation of Seasat-derived winds are described in terms of the time series of hourly wind observations from the buoys and in terms of the techniques used to produce 20- and 30-min average winds from the ships. Attention is given to the comparison data, the synoptic scale wind, turbulence concepts, the data buoy winds, Ocean Weather Station PAPA, the oceanographer data, and the results from Ocean Station PAPA Ship Quadra and from the oceanographer. Sources of scatter in the comparison data are reviewed.
1983-05-01
SMP has sinkers attached to wire rope within the water column. This location of sinkers was not duplicated on the TCP moor because of possible wear and...breaking (new chain) 1-3/4" wire rope breaking strength is approx. 224. kips; F.S. = 6.4 against breaking (new rope) Buoy, dia=9.5’,h=5’ buoy freeboard is...6.4 against breakingconnecting agis 1-3/4" wire rope with J b- chain tails 13 See Appendix B for details of the mooring buoy design and Appendix C
Belchansky, Gennady I.; Douglas, David C.; Mordvintsev, Ilia N.; Platonov, Nikita G.
2004-01-01
Accurate calculation of the time of melt onset, freeze onset, and melt duration over Arctic sea-ice area is crucial for climate and global change studies because it affects accuracy of surface energy balance estimates. This comparative study evaluates several methods used to estimate sea-ice melt and freeze onset dates: (1) the melt onset database derived from SSM/I passive microwave brightness temperatures (Tbs) using Drobot and Anderson's [J. Geophys. Res. 106 (2001) 24033] Advanced Horizontal Range Algorithm (AHRA) and distributed by the National Snow and Ice Data Center (NSIDC); (2) the International Arctic Buoy Program/Polar Exchange at the Sea (IABP/POLES) surface air temperatures (SATs); (3) an elaborated version of the AHRA that uses IABP/POLES to avoid anomalous results (Passive Microwave and Surface Temperature Analysis [PMSTA]); (4) another elaborated version of the AHRA that uses Tb variance to avoid anomalous results (Mean Differences and Standard Deviation Analysis [MDSDA]); (5) Smith's [J. Geophys. Res. 103 (1998) 27753] vertically polarized Tb algorithm for estimating melt onset in multiyear (MY) ice (SSM/I 19V–37V); and (6) analyses of concurrent backscattering cross section (σ°) and brightness temperature (Tb) from OKEAN-01 satellite series. Melt onset and freeze onset maps were created and compared to understand how the estimates vary between different satellite instruments and methods over different Arctic sea-ice regions. Comparisons were made to evaluate relative sensitivities among the methods to slight adjustments of the Tbcalibration coefficients and algorithm threshold values. Compared to the PMSTA method, the AHRA method tended to estimate significantly earlier melt dates, likely caused by the AHRA's susceptibility to prematurely identify melt onset conditions. In contrast, the IABP/POLES surface air temperature data tended to estimate later melt and earlier freeze in all but perennial ice. The MDSDA method was least sensitive to small adjustments of the SMMR–SSM/I inter-satellite calibration coefficients. Differences among methods varied by latitude. Freeze onset dates among methods were most disparate in southern latitudes, and tended to converge northward. Surface air temperatures (IABP/POLES) indicated freeze onset well before the MDSDA method, especially in southern peripheral seas, while PMSTA freeze estimates were generally intermediate. Surface air temperature data estimated latest melt onset dates in southern latitudes, but earliest melt onset in northern latitudes. The PMSTA estimated earliest melt onset dates in southern regions, and converged with the MDSDA northward. Because sea-ice melt and freeze are dynamical transitional processes, differences among these methods are associated with differing sensitivities to changing stages of environmental and physical development. These studies contribute to the growing body of documentation about the levels of disparity obtained when Arctic seasonal transition parameters are estimated using various types of microwave data and algorithms.
Wave Power Demonstration Project at Reedsport, Oregon
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mekhiche, Mike; Downie, Bruce
2013-10-21
Ocean wave power can be a significant source of large‐scale, renewable energy for the US electrical grid. The Electrical Power Research Institute (EPRI) conservatively estimated that 20% of all US electricity could be generated by wave energy. Ocean Power Technologies, Inc. (OPT), with funding from private sources and the US Navy, developed the PowerBuoy to generate renewable energy from the readily available power in ocean waves. OPT's PowerBuoy converts the energy in ocean waves to electricity using the rise and fall of waves to move the buoy up and down (mechanical stroking) which drives an electric generator. This electricity ismore » then conditioned and transmitted ashore as high‐voltage power via underwater cable. OPT's wave power generation system includes sophisticated techniques to automatically tune the system for efficient conversion of random wave energy into low cost green electricity, for disconnecting the system in large waves for hardware safety and protection, and for automatically restoring operation when wave conditions normalize. As the first utility scale wave power project in the US, the Wave Power Demonstration Project at Reedsport, OR, will consist of 10 PowerBuoys located 2.5 miles off the coast. This U.S. Department of Energy Grant funding along with funding from PNGC Power, an Oregon‐based electric power cooperative, was utilized for the design completion, fabrication, assembly and factory testing of the first PowerBuoy for the Reedsport project. At this time, the design and fabrication of this first PowerBuoy and factory testing of the power take‐off subsystem are complete; additionally the power take‐off subsystem has been successfully integrated into the spar.« less
Dynamic analysis of propulsion mechanism directly driven by wave energy for marine mobile buoy
NASA Astrophysics Data System (ADS)
Yu, Zhenjiang; Zheng, Zhongqiang; Yang, Xiaoguang; Chang, Zongyu
2016-07-01
Marine mobile buoy(MMB) have many potential applications in the maritime industry and ocean science. Great progress has been made, however the technology in this area is far from maturity in theory and faced with many difficulties in application. A dynamic model of the propulsion mechanism is very necessary for optimizing the parameters of the MMB, especially with consideration of hydrodynamic force. The principle of wave-driven propulsion mechanism is briefly introduced. To set a theory foundation for study on the MMB, a dynamic model of the propulsion mechanism of the MMB is obtained. The responses of the motion of the platform and the hydrofoil are obtained by using a numerical integration method to solve the ordinary differential equations. A simplified form of the motion equations is reached by omitting terms with high order small values. The relationship among the heave motion of the buoy, stiffness of the elastic components, and the forward speed can be obtained by using these simplified equations. The dynamic analysis show the following: The angle of displacement of foil is fairly small with the biggest value around 0.3 rad; The speed of mobile buoy and the angle of hydrofoil increased gradually with the increase of heave motion of buoy; The relationship among heaven motion, stiffness and attack angle is that heave motion leads to the angle change of foil whereas the item of speed or push function is determined by vertical velocity and angle, therefore, the heave motion and stiffness can affect the motion of buoy significantly if the size of hydrofoil is kept constant. The proposed model is provided to optimize the parameters of the MMB and a foundation is laid for improving the performance of the MMB.
The VIMS CBOS Observing System Buoy, an Initial Scientific Analysis
NASA Astrophysics Data System (ADS)
Brasseur, L. H.; Brubaker, J. M.; Friedrichs, C. T.; Wright, L. D.
2004-12-01
The Virginia Institute of Marine Science (VIMS) has recently deployed a data buoy at Gloucester Point, York River, Virginia as part of the Chesapeake Bay Observing System (CBOS). The data streams collected by the buoy and its associated sensors are wind speed and direction, incoming solar radiation, air temperature, water temperature, salinity, turbidity, fluorescence, and dissolved oxygen. In addition, water velocities throughout the water column are recorded every 5 minutes and wave statistics including directional wave spectra are calculated every hour from an upward looking RD Instruments Acoustic Doppler Current Profiler (ADCP) in 8 meters of water in conjunction with the data buoy. All data are collected in real time and are available to scientists with a 15 minute to 1 hour time lag. These data are used in conjunction with other long tem data sets in the York River and lower Chesapeake Bay such as the Chesapeake Bay National Estuarine Research Reserve (CBNERR) sites' water quality data in the York River and USGS stream flow data to investigate several questions of scientific interest. One of these questions is the observed reverse salinity gradient in the York River during spring flood tides. It was previously thought that this was caused by a temporal mismatch in the phase of flood tide between the lower Chesapeake Bay and the mouth of the York River subestuary only during spring tides when the currents are strongest and the tidal range is large. In 2004, however, this effect can be seen during both spring and neap tides on several occasions in the spring and summer. This phenomenon and others are evaluated in the context of the VIMS observing system buoy and the initial data collected from the buoy are also evaluated in terms of instrument accuracy, ease of data retrieval, and possible uses for this information.
NASA Astrophysics Data System (ADS)
Biebow, N.; Lembke-Jene, L.; Wolff-Boenisch, B.; Bergamasco, A.; De Santis, L.; Eldholm, O.; Mevel, C.; Willmott, V.; Thiede, J.
2011-12-01
Despite significant advances in Arctic and Antarctic marine science over the past years, the polar Southern Ocean remains a formidable frontier due to challenging technical and operational requirements. Thus, key data and observations from this important region are still missing or lack adequate lateral and temporal coverage, especially from time slots outside optimal weather seasons and ice conditions. These barriers combined with the obligation to efficiently use financial resources and funding for expeditions call for new approaches to create optimally equipped, but cost-effective infrastructures. These must serve the international science community in a dedicated long-term mode and enable participation in multi-disciplinary expeditions, with secured access to optimally equipped marine platforms for world-class research in a wide range of Antarctic science topics. The high operational and technical performance capacity of a future joint European Research Icebreaker and Deep-sea Drilling Vessel (the AURORA BOREALIS concept) aims at integrating still separately operating national science programmes with different strategic priorities into joint development of long-term research missions with international cooperation both in Arctic and Antarctica. The icebreaker is planned to enable, as a worldwide first, autonomous year-round operations in the central Arctic and polar Southern Ocean, including severest ice conditions in winter, and serving all polar marine disciplines. It will facilitate the implementation of atmospheric, oceanographic, cryospheric or geophysical observatories for long-term monitoring of the polar environment. Access to the biosphere and hydrosphere e.g. beneath ice shelves or in remote regions is made possible by acting as advanced deployment platform for instruments, robotic and autonomous vehicles and ship-based air operations. In addition to a report on the long-term strategic science and operational planning objectives, we describe foreseen on- and offshore science support infrastructure, recommended operational and scientific support structures and the relevance of AURORA BOREALIS for other present and future Antarctic science programmes and initiatives.
The December 2015 North Pole Warming Event and the Increasing Occurrence of Such Events
Moore, G. W. K.
2016-01-01
In late December 2015, widespread media interest revolved around forecasts that the surface air temperature at the North Pole would rise above freezing. Although there has been significant interest in the enhanced warming that is occurring at high northern latitudes, a process known as arctic amplification, remarkably little is known about these midwinter warming events at the pole including their frequency, duration and magnitude as well as the environmental conditions responsible for their occurrence. Here we use buoy and radiosonde data along with operational weather forecasts and atmospheric reanalyses to show that such events are associated with surface cyclones near the pole as well as a highly perturbed polar vortex. They occur once or twice each decade with the earliest identified event taking place in 1959. In addition, the warmest midwinter temperatures at the North Pole have been increasing at a rate that is twice as large as that for mean midwinter temperatures at the pole. It is argued that this enhanced trend is consistent with the loss of winter sea ice from the Nordic Seas that moves the reservoir of warm air over this region northwards making it easier for weather systems to transport this heat polewards. PMID:27976745
11. BUOY DECK, NEAR PILOT HOUSE SUPERSTRUCTURE, LOOKING TOWARDS HATCH ...
11. BUOY DECK, NEAR PILOT HOUSE SUPERSTRUCTURE, LOOKING TOWARDS HATCH DOOR INTO WINCH ROOM IN THE SUPERSTRUCTURE (LABELED AT PASSAGE & HYDRAULIC MACHINERY ON PLAN). - U.S. Coast Guard Cutter WHITE HEATH, USGS Integrated Support Command Boston, 427 Commercial Street, Boston, Suffolk County, MA
Port Planning for Seagoing Buoy Tender (WLB) Attrition
DOT National Transportation Integrated Search
1988-07-01
The Coast Guard operates a diverse complement of servicing vessels to service aids to navigation. Of these, the fleet of 28 WLB's (seagoing buoy tenders) is the largest and oldest. Over 40 years old, these vessels are well beyond the end of their eco...
Tracking buoys research for oil spilling with the wireless charging equipment
NASA Astrophysics Data System (ADS)
Cui, Di; Zhao, Ping
2018-03-01
This paper describes thewirelesscharging equipment for achieving oil spill tracking buoys detection in satellite images acquired after tanker accidents or ship oil spill accidents. This information could allow the evolution of residues dumped at sea to be tracked. The validity of this process is demonstrated using several experiment acquired over several regions (Dalian and Tianjin coasts in China), in which a tanker accident has occurred and as a consequence oil spillage has taken place. Thus, this purpose of paper is developed for the active surveillance and rapid response to marine oil spills tracking buoys with wirelesscharging equipmentis important and essential to environment protection. It may appears of leak places for the Wire Charging Equipment for marine oil spills tracking buoys monitoring needs, and achieved instant alarm technology and equipment, guarantees leak occurred timely obtained alarm information. In order toproviding oil spill accidents emergency quickly reaction time and prepared. The maximum degree reduce oil leak and accidents caused influences are ensured.
An intelligent subsurface buoy design for measuring ocean ambient noise
NASA Astrophysics Data System (ADS)
Li, Bing; Wang, Lei
2012-11-01
A type of ultra-low power subsurface buoy system is designed to measure and record ocean ambient noise data. The buoy utilizes a vector hydrophone (pass band 20Hz-1.2kHz) and a 6-element vertical hydrophone array (pass band 20Hz-2kHz) to measure ocean ambient noise. The acoustic signals are passed through an automatically modified gain, a band pass filter, and an analog-to-digital (A/D) conversion module. They are then stored in high-capacity flash memory. In order to identify the direction of noise source, the vector sensor measuring system has integrated an electric-magnetic compass. The system provides a low-rate underwater acoustic communication system which is used to report the buoy state information and a high-speed USB interface which is used to retrieve the recorded data on deck. The whole system weighs about 125kg and can operate autonomously for more than 72 hours. The system's main architecture and the sea-trial test results are provided in this paper.
Lagrangian circulation study near Cape Henry, Virginia. [Chesapeake Bay
NASA Technical Reports Server (NTRS)
Johnson, R. E.
1981-01-01
A study of the circulation near Cape Henry, Virginia, was made using surface and seabed drifters and radar tracked surface buoys coupled to subsurface drag plates. Drifter releases were conducted on a line normal to the beach just south of Cape Henry. Surface drifter recoveries were few; wind effects were strongly noted. Seabed drifter recoveries all exhibited onshore motion into Chesapeake Bay. Strong winds also affected seabed recoveries, tending to move them farther before recovery. Buoy trajectories in the vicinity of Cape Henry appeared to be of an irrotational nature, showing a clockwise rotary tide motion. Nearest the cape, the buoy motion elongated to almost parallel depth contours around the cape. Buoy motion under the action of strong winds showed that currents to at least the depth of the drag plates substantially are altered from those of low wind conditions near the Bay mouth. Only partial evidence could be found to support the presence of a clockwise nontidal eddy at Virginia Beach, south of Cape Henry.
Texas Automated Buoy System 1995-2005 and Beyond
NASA Astrophysics Data System (ADS)
Guinasso, N. L.; Bender, L. C.; Walpert, J. N.; Lee, L. L.; Campbell, L.; Hetland, R. D.; Howard, M. K.; Martin, R. D.
2005-05-01
TABS was established in l995 to provide data to assess oil spill movement along Texas coast for the Texas General Land Office Oil Spill Prevention and Response Program. A system of nine automated buoys provide wind and current data in near real time. Two of these buoys are supported by the Flower Garden Banks Joint Industry Program. A TABS web site provides a public interface to view and download the data. A real time data analysis web page presents a wide variety of useful data products derived from the field measurements. Integration efforts now underway include transfer of buoy data to the National Data Buoy Center for quality control and incorporation into the Global Telecommunications Stream. The TGLO ocean circulation nowcast/forecast modeling system has been in continuous operation since 1998. Two models, POM and ROMS, are used to produce forecasts of near-surface wind driven currents up to 48 hours into the future. Both models are driven using wind fields obtained from the NAM (formerly Eta) forecast models operated by NOAA NCEP. Wind and current fields are displayed on websites in both static and animated forms and are updated four times per day. Under funding from the SURA/SCOOP program we are; 1) revamping the system to conform with the evolving Data Management and Communications (DMAC) framework adopted by the NSF Orion and OCEAN.US IOOS programs, 2) producing model-data comparisons, and 3) integrating the wind and current fields into the GNOME oil trajectory model used by NOAA/Hazmat. Academic research is planned to assimilate near real-time observations from TABS buoys and some 30-40 ADCP instruments scheduled to be mounted on offshore oil platforms in early 2005. Texas Automated Buoy System (TABS) and its associated modeling efforts provide a reliable source of accurate, up-to-date information on currents along the Texas coast. As the nation embarks on the development of an Integrated Ocean Observing System (IOOS), TABS will be an active participant as a foundational regional component to the national backbone of ocean observations.
A methodology for spectral wave model evaluation
NASA Astrophysics Data System (ADS)
Siqueira, S. A.; Edwards, K. L.; Rogers, W. E.
2017-12-01
Model evaluation is accomplished by comparing bulk parameters (e.g., significant wave height, energy period, and mean square slope (MSS)) calculated from the model energy spectra with those calculated from buoy energy spectra. Quality control of the observed data and choice of the frequency range from which the bulk parameters are calculated are critical steps in ensuring the validity of the model-data comparison. The compared frequency range of each observation and the analogous model output must be identical, and the optimal frequency range depends in part on the reliability of the observed spectra. National Data Buoy Center 3-m discus buoy spectra are unreliable above 0.3 Hz due to a non-optimal buoy response function correction. As such, the upper end of the spectrum should not be included when comparing a model to these data. Bioufouling of Waverider buoys must be detected, as it can harm the hydrodynamic response of the buoy at high frequencies, thereby rendering the upper part of the spectrum unsuitable for comparison. An important consideration is that the intentional exclusion of high frequency energy from a validation due to data quality concerns (above) can have major implications for validation exercises, especially for parameters such as the third and fourth moments of the spectrum (related to Stokes drift and MSS, respectively); final conclusions can be strongly altered. We demonstrate this by comparing outcomes with and without the exclusion, in a case where a Waverider buoy is believed to be free of biofouling. Determination of the appropriate frequency range is not limited to the observed spectra. Model evaluation involves considering whether all relevant frequencies are included. Guidance to make this decision is based on analysis of observed spectra. Two model frequency lower limits were considered. Energy in the observed spectrum below the model lower limit was calculated for each. For locations where long swell is a component of the wave climate, omitting the energy in the frequency band between the two lower limits tested can lead to an incomplete characterization of model performance. This methodology was developed to aid in selecting a comparison frequency range that does not needlessly increase computational expense and does not exclude energy to the detriment of model performance analysis.
Counter-narcotic acoustic buoy (CNAB)
NASA Astrophysics Data System (ADS)
Bailey, Mark E.
2004-09-01
As a means to detect drug trafficking in a maritime environment, the Counter Narcotic Acoustic Buoy is part of an inexpensive system designed to detect "Go Fast" boats and report via satellite to a designated location. A go fast boat for this evaluation is defined as any boat with twin 200 horsepower outboard engines. The buoy is designed for deployment in salt water at depths ranging from 50 to 600 feet and can be easily deployed by one or two persons. Detections are based on noise energy exceeding a preset level within a frequency band associated with the go fast boat's acoustic signature. Detection ranges have been demonstrated to greater than three nautical miles.
46 CFR 160.050-5 - Sampling, tests, and inspection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... satisfied that the ring life buoys meet this subpart. Each lot must demonstrate— (1) First quality... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular... necessary to maintain quality control and to monitor compliance with the requirements of this subchapter. (b...
46 CFR 160.050-5 - Sampling, tests, and inspection.
Code of Federal Regulations, 2014 CFR
2014-10-01
... satisfied that the ring life buoys meet this subpart. Each lot must demonstrate— (1) First quality... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular... necessary to maintain quality control and to monitor compliance with the requirements of this subchapter. (b...
46 CFR 160.050-5 - Sampling, tests, and inspection.
Code of Federal Regulations, 2012 CFR
2012-10-01
... satisfied that the ring life buoys meet this subpart. Each lot must demonstrate— (1) First quality... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular... necessary to maintain quality control and to monitor compliance with the requirements of this subchapter. (b...
46 CFR 160.050-5 - Sampling, tests, and inspection.
Code of Federal Regulations, 2013 CFR
2013-10-01
... satisfied that the ring life buoys meet this subpart. Each lot must demonstrate— (1) First quality... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular... necessary to maintain quality control and to monitor compliance with the requirements of this subchapter. (b...
46 CFR 160.050-5 - Sampling, tests, and inspection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... satisfied that the ring life buoys meet this subpart. Each lot must demonstrate— (1) First quality... MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Specification for a Buoy, Life Ring, Unicellular... necessary to maintain quality control and to monitor compliance with the requirements of this subchapter. (b...
Information And Data-Sharing Plan of IPY China Activity
NASA Astrophysics Data System (ADS)
Zhang, X.; Cheng, W.
2007-12-01
Polar Data-Sharing is an effective resolution to global system and polar science problems and to interdisciplinary and sustainable study, as well as an important means to deal with IPY scientific heritages and realize IPY goals. Corresponding to IPY Data-Sharing policies, Information and Data-Sharing Plan was listed in five sub-plans of IPY Chinese Programme launched in March, 2007,they are Scientific research program of the Prydz Bay, Amery Ice Shelf and Dome A transects(short title:'PANDA'), the Arctic Scientific Research Expedition Plan, International Cooperation Plan, Information and Data-Sharing Plan, Education and Outreach. China, since the foundation of Antarctic Zhongshan Station in 1989, has carried out systematic scientific expeditions and researches in Larsemann Hills, Prydz Bay and the neighbouring sea areas, organized 14 Prydz Bay oceanographic investigations, 3 Amery Ice Shelf expeditions, 4 Grove Mountains expeditions and 5 inland ice cap scientific expeditions. 2 comprehensive oceanographic investigations in the Arctic Ocean were conducted in 1999 and 2003, acquired a large amount of data and samples in PANDA section and fan areas of Pacific Ocean in the Arctic Ocean. A mechanism of basic data submitting ,sharing and archiving has been gradually set up since 2000. Presently, Polar Science Database and Polar Sample Resource Sharing Platform of China with the aim of sharing polar data and samples has been initially established and began to provide sharing service to domestic and oversea users. According to IPY Chinese Activity, 2 scientific expeditions in the Arctic Ocean, 3 in the South Ocean, 2 at Amery Ice Shelf, 1 on Grove Mountains and 2 inland ice cap expeditions on Dome A will be carried out during IPY period. According to the experiences accumulated in the past and the jobs in the future, the Information and Data- Sharing Plan, during 2007-2010, will save, archive, and provide exchange and sharing services upon the data obtained by scientific expeditions on the site of IPY Chinese Programme. Meanwhile, focusing on areas in east Antarctic Dome A-Grove Mountain-Zhongshan Station-Amery Ice Shelf-Prydz Bay Section and the fan areas of Pacific Ocean in the Arctic Ocean, the Plan will also collect and integrate IPY data and historical data and establish database of PANDA Section and the Arctic Ocean. The details are as follows: On the basis of integrating the observed data acquired during the expeditions of China, the Plan will, adopting portal technology, develop 5 subject databases (English version included):(1) Database of Zhongshan Station- Dome A inner land ice cap section;(2) Database of interaction of ocean-ice-atmosphere-ice shelf in east Antarctica;(3) Database of geological and glaciological advance and retreat evolvement in Grove Mountains; (4) Database of Solar Terrestrial Physics at Zhongshan Station; (5) Oceanographic database of fan area of Pacific Ocean in the Arctic Ocean. CN-NADC of PRIC is the institute which assumes the responsibility for the Plan, specifically, it coordinates and organizes the operation of the Plan which includes data management, developing the portal of data and information sharing, and international exchanges. The specific assignments under the Plan will be carried out by research institutes under CAS (Chinese Academy of Sciences), SOA ( State Oceanic Administration), State Bureau of Surveying and Mapping and Ministry of Education.
NASA Technical Reports Server (NTRS)
Ray, Richard D.; Beckley, B. D.
2003-01-01
The verification phase of the Jason-1 satellite altimeter mission presents a unique opportunity for comparing near-simultaneous, independent satellite measurements. We here examine simultaneous significant wave height measurements by the Jason-1 and Topex/Poseidon altimeters. These data are also compared with in-situ measurements from deep-ocean buoys and with predicted wave heights from the Wave Watch 111 operational model. The rms difference between Jason and Topex wave heights is 21 cm, and this can be further lowered by application of median filters to reduce high-frequency noise. This noise is slightly larger in the Jason dataset, amounting to about 7 cm rms for frequencies above 0.05 Hz, which is the frequency at which the coherence between Topex and Jason measurements drops to zero. The probability density function for Jason shows a dearth of small waves relative to Topex. Buoy comparisons confirm that this problem lies with the Jason measurements. The buoy comparisons confirm previous reports that Topex wave heights are roughly 5% smaller than buoy measurements for waves between 2 and 5m; Jason heights in general are 2.7% smaller than Topex. Spurious dips in the Topex density function for 3- and 6-meter waves, a problem that has existed since the beginning of the mission, can be solved by waveform retracking..
Dubelaar, G B; Gerritzen, P L; Beeker, A E; Jonker, R R; Tangen, K
1999-12-01
The high costs of microscopical determination and counting of phytoplankton often limit sampling frequencies below an acceptable level for the monitoring of dynamic ecosystems. Although having a limited discrimination power, flow cytometry allows the analysis of large numbers of samples to a level that is sufficient for many basic monitoring jobs. For this purpose, flow cytometers should not be restricted to research laboratories. We report here on the development of an in situ flow cytometer for autonomous operation inside a small moored buoy or on other platforms. Operational specifications served a wide range of applications in the aquatic field. Specific conditions had to be met with respect to the operation platform and autonomy. A small, battery-operated flow cytometer resulted, requiring no external sheath fluid supply. Because it was designed to operate in a buoy, we call it CytoBuoy. Sampling, analysis, and radio transmission of the data proceed automatically at user-defined intervals. A powerful feature is the acquisition and radio transmission of full detector pulse shapes of each particle. This provides valuable morphological information for particles larger than the 5-microm laser focus. CytoBuoy allows on-line in situ particle analysis, estimation of phytoplankton biomass, and discrimination between different phytoplankton groups. This will increase the applicability of flow cytometry in the field of environmental monitoring. Copyright 1999 Wiley-Liss, Inc.
High frequency monitoring of the coastal marine environment using the MAREL buoy.
Blain, S; Guillou, J; Tréguer, P; Woerther, P; Delauney, L; Follenfant, E; Gontier, O; Hamon, M; Leilde, B; Masson, A; Tartu, C; Vuillemin, R
2004-06-01
The MAREL Iroise data buoy provides physico-chemical measurements acquired in surface marine water in continuous and autonomous mode. The water is pumped 1.5 m from below the surface through a sampling pipe and flows through the measuring cell located in the floating structure. Technological innovations implemented inside the measuring cell atop the buoy allow a continuous cleaning of the sensor, while injection of chloride ions into the circuit prevents biological fouling. Specific sensors for temperature, salinity, oxygen and fluorescence investigated in this paper have been evaluated to guarantee measurement precision over a 3 month period. A bi-directional link under Internet TCP-IP protocols is used for data, alarms and remote-control transmissions with the land-based data centre. Herein, we present a 29 month record for 4 parameters measured using a MAREL buoy moored in a coastal environment (Iroise Sea, Brest, France). The accuracy of the data provided by the buoy is assessed by comparison with measurements of sea water weekly sampled at the same site as part of SOMLIT (Service d'Observation du Milieu LIToral), the French network for monitoring of the coastal environment. Some particular events (impact of intensive fresh water discharges, dynamics of a fast phytoplankton bloom) are also presented, demonstrating the worth of monitoring a highly variable environment with a high frequency continuous reliable system.
Numerical modeling of a spherical buoy moored by a cable in three dimensions
NASA Astrophysics Data System (ADS)
Zhu, Xiangqian; Yoo, Wan-Suk
2016-05-01
Floating facilities have been studied based on the static analysis of mooring cables over the past decades. To analyze the floating system of a spherical buoy moored by a cable with a higher accuracy than before, the dynamics of the cables are considered in the construction of the numerical modeling. The cable modeling is established based on a new element frame through which the hydrodynamic loads are expressed efficiently. The accuracy of the cable modeling is verified with an experiment that is conducted by a catenary chain moving in a water tank. In addition, the modeling of a spherical buoy is established with respect to a spherical coordinate in three dimensions, which can suffers the gravity, the variable buoyancy and Froude-Krylov loads. Finally, the numerical modeling for the system of a spherical buoy moored by a cable is established, and a virtual simulation is proceeded with the X- and Y-directional linear waves and the X-directional current. The comparison with the commercial simulation code ProteusDS indicates that the system is accurately analyzed by the numerical modeling. The tensions within the cable, the motions of the system, and the relationship between the motions and waves are illustrated according to the defined sea state. The dynamics of the cables should be considered in analyzing the floating system of a spherical buoy moored by a cable.
Analysis and prediction of ocean swell using instrumented buoys
NASA Technical Reports Server (NTRS)
Mettlach, Theodore; Wang, David; Wittmann, Paul
1994-01-01
During the period 20-23 September 1990, the remnants of Supertyphoon Flo moved into the central North Pacific Ocean with sustained wind speeds of 28 m/s. The strong wind and large fetch area associated with this storm generated long-period swell that propagated to the west coast of North America. National Data Buoy Center moored-buoy stations, located in a network that ranged from the Gulf of Alaska to the California Bight, provided wave spectral estimates of the swell from this storm. The greatest dominant wave periods measured were approximately 20-25 s, and significant wave heights measured ranged from 3 to 8 m. Wave spectra from an array of three nondirectional buoys are used to find the source of the long-period swell. Directional wave spectra from a heave-pitch-roll buoy are also used to make an independent estimate of the source of the swell. The ridge-line method, using time-frequency contour plots of wave spectral energy density, is used to determine the time of swell generation, which is used with the appropriate surface pressure analysis to infer the swell generation area. The diagnosed sources of the swell are also compared with nowcasts from the Global Spectral Ocean Wave Model of the Fleet Numerical Oceanography Center. A simple method of predicting the propagation of ocean swell, by applying a simple kinematic model of wave propagation to the estimated point and time source, is demonstrated.
Simple and effective method to lock buoy position to ocean currents
NASA Technical Reports Server (NTRS)
Vachon, W. A.; Dahlen, J. M.
1975-01-01
Window-shade drogue, used with drifting buoys to keep them moving with current at speed as close to that of current as possible, has drag coefficient of 1.93 compared to maximum of 1.52 for previous drogues. It is remarkably simple to construct, use, and store.
DOT National Transportation Integrated Search
1993-08-01
The report documents the results of the Volpe Center's analysis of the number of replacement stern-loading buoy boats (BUSLRs) required for the U.S. Coast Guard's Aids to Navigation (ATON) mission. At present, 19 Coast Guard Aids to Navigation Teams ...
Edwards, Brian D.; Childs, Jonathan R.; Triezenberg, Peter J.; Danforth, William W.; Gibbons, Helen
2013-01-01
In August and September 2010, the U.S. Geological Survey, in cooperation with Natural Resources Canada, Geological Survey of Canada, conducted bathymetric and geophysical surveys in the Beaufort Sea and eastern Arctic Ocean aboard the U.S. Coast Guard Cutter Healy. The principal objective of this mission to the high Arctic was to acquire data in support of a delineation of the outer limits of the U.S. and Canadian Extended Continental Shelf in the Arctic Ocean, in accordance with the provisions of Article 76 of the United Nations Convention on the Law of the Sea. The Healy was accompanied by the Canadian Coast Guard icebreaker Louis S. St-Laurent. The scientific parties on board the two vessels consisted principally of staff from the U.S. Geological Survey (Healy), and the Geological Survey of Canada and the Canadian Hydrographic Service (Louis). The crew also included marine-mammal observers, Native-community observers, ice observers, and biologists conducting research of opportunity in the Arctic Ocean. Despite interruptions necessitated by three medical emergencies, the joint survey proved largely successful. The Healy collected 7,201 trackline-kilometers of swath (multibeam) bathymetry (47,663 square kilometers) and CHIRP subbottom data, with accompanying marine gravity measurements, and expendable bathythermograph data. The Louis acquired 3,673 trackline-kilometers of multichannel seismic (airgun) deep-penetration reflection data along 25 continuous profiles, as well as 34 sonobuoy refraction stations and 9,500 trackline-kilometers of single-beam bathymetry. The coordinated efforts of the two vessels resulted in seismic-reflection-profile data that were of much higher quality and continuity than if the data had been acquired with a single vessel alone. The equipment-failure rate of the seismic equipment aboard the Louis was greatly reduced when the Healy led as the ice breaker. When ice conditions proved too severe to deploy the seismic system, the Louis led the Healy, resulting in much improved quality of the swath bathymetric and CHIRP subbottom data in comparison with data collected either by the Healy in the lead or the Healy working alone. During periods when the Healy was operating alone (principally when the Louis was diverted for emergency medical evacuations or ship repairs), the Healy was able to deploy a piston-core-sampler (10 meters maximum potential recovery depending on configuration). The coring operations resulted in recovery of cores at five locations ranging from 2.4 to 5.7 meters in length from water depths ranging from 1,157 to 3,700 meters. One of these cores sited on the Alaskan margin recovered the first reported occurrence of methane hydrate from the Arctic Ocean. Ancillary science objectives, including ice observations and deployment of ice-monitoring buoys and water-column sampling to measure acidification of Arctic waters were successfully conducted. The water-column sampling included using 10 full-ocean-depth, water-sampling casts with accompanying conductivity-temperature-depth measurements. Except for the data deemed proprietary, data from the cruise have been archived and are available for download at the National Geophysical Data Center and at cooperating organizations. Outreach staff and guest teachers aboard the two vessels provided near-real-time connection between the research activities and the public through online blogs, web pages, and other media.
Meteorological buoy measurements in the Iceland Sea, 2007-2009
NASA Astrophysics Data System (ADS)
Nína Petersen, Guðrún
2017-10-01
The Icelandic Meteorological Office (IMO) conducted meteorological buoy measurements in the central Iceland Sea in the time period 2007-2009, specifically in the northern Dreki area on the southern segment of the Jan Mayen Ridge. Due to difficulties in deployment and operations, in situ measurements in this region are sparse. Here the buoy, deployment and measurements are described with the aim of giving a future user of the data set information that is as comprehensive as possible. The data set has been quality-checked, suspect data removed and the data set made publicly available from PANGAEA Data Publisher (https://doi.org/10.1594/PANGAEA.876206).
Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008
Marelle, L.; Raut, Jean-Christophe; Thomas, J. L.; ...
2015-04-10
During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM 2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM 2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we findmore » that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM 10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM 2.5, modeled black carbon and SO 4 = concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m −2, peaking at +3.3 W m −2 at noon over Scandinavia and Finland.« less
11. BUOY DECK, NEAR PILOT HOUSE SUPERSTRUCTURE, LOOKING TOWARDS HATCH ...
11. BUOY DECK, NEAR PILOT HOUSE SUPERSTRUCTURE, LOOKING TOWARDS HATCH DOOR INTO WINCH ROOM IN THE SUPERSTRUCTURE (LABELED AS FASSAGE & HYDRAULIC MACHINERY ON PLAN), SHOWING UNDERSIDE OF GEARED WHEEL OF BOOM. - U.S. Coast Guard Cutter WHITE LUPINE, U.S. Coast Guard Station Rockland, east end of Tillson Avenue, Rockland, Knox County, ME
NREL Deploys Wave and Tidal Measurement Buoys | News | NREL
various wave and tidal models, and in turn, reduce risks for developers. These buoys allow researchers to "better understand the limitations and errors in existing global wave models," says Kilcher using NREL, laboratory, and U.S. Department of Energy published models, the team identified likely
46 CFR 164.019-3 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Guard-approved PFDs. Commandant means the Chief of the Lifesaving and Fire Safety Division, Office of Engineering and Design Standards, U.S. Coast Guard. Address: Commandant (CG-ENG-4), Attn: Lifesaving and Fire... and III. 3 III. 4B IV (all Ring Buoys). 4BC IV (Buoyant Cushions). 4RB IV (Recreational Ring Buoys...
46 CFR 164.019-3 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Guard-approved PFDs. Commandant means the Chief of the Lifesaving and Fire Safety Division, Office of Engineering and Design Standards, U.S. Coast Guard. Address: Commandant (CG-ENG-4), Attn: Lifesaving and Fire... and III. 3 III. 4B IV (all Ring Buoys). 4BC IV (Buoyant Cushions). 4RB IV (Recreational Ring Buoys...
The Great Build-a-Buoy Challenge
ERIC Educational Resources Information Center
Dickerson, Daniel; Hathcock, Stephanie; Stonier, Frank; Levin, Doug
2012-01-01
As Science, Technology, Engineering, and Mathematics (STEM) Education continues to become more visible in elementary school curricula, the need for activities that address STEM content is growing. Build-A-Buoy is one such activity. This activity was developed by Doug Levin in 2008 when he was an education coordinator for the NOAA Chesapeake Bay…
Pacific Ocean buoy temperature date
Pacific Ocean buoy temperature dataThis dataset is associated with the following publication:Carbone, F., M. Landis, C.N. Gencarelli, A. Naccarato, F. Sprovieri, F. De Simone, I.M. Hedgecock, and N. Pirrone. Sea surface temperature variation linked to elemental mercury concentrations measured on Mauna Loa. GEOPHYSICAL RESEARCH LETTERS. American Geophysical Union, Washington, DC, USA, online, (2016).
Using Buoy and Radar Data to Study Sudden Wind Gusts Over Coastal Regions
NASA Technical Reports Server (NTRS)
Priftis, Georgios; Chronis, Themis; Lang, Timothy J.
2017-01-01
Significant sudden wind gusts can pose a threat to aviation near the coastline, as well as small (sailing) boats and commercial ships approaching the ports. Such cases can result in wind speed changes of more than an order of magnitude within 5 minutes, which can then last up to 20 minutes or more. Although the constellation of scatterometers is a good means of studying maritime convection, those sudden gusts are not easily captured because of the low time resolution. The National Data Buoy Center (NDBC) provides continuous measurements of wind speed and direction along the US coastal regions every 6 minutes. Buoys are platforms placed at specific places on the seas, especially along coastlines, providing data for atmospheric and oceanic studies. Next Generation Radars (NEXRADs), after the recent upgrade of the network to dual-pol systems, offer enhanced capabilities to study atmospheric phenomena. NEXRADs provide continuous full-volume scans approximately every 5 minutes and therefore are close to the time resolution of the buoy measurements. Use of single- Doppler retrievals might also provide a means of further validation.
NASA Astrophysics Data System (ADS)
Dixon, T. H.; Xie, S.; Malservisi, R.; Lembke, C.; Iannaccone, G.; Law, J.; Rodgers, M.; Russell, R.; Voss, N. K.
2017-12-01
A GPS-buoy system has been built and is currently undergoing test to measure precise 3D sea floor motion in the shallow (less than 200 m) continental shelf environment. Offshore deformation is undersampled in most subduction zones. In Cascadia, the shallow shelf environment constitutes roughly 20%-25% of the offshore area between the coastline and the trench. In the system being tested, the GPS receiver at the top of the buoy is connected to the sea floor through a rigid structure supported by a float. A similar design has been used by INGV (Italy) to measure vertical deformation on the sea floor near the Campi Flegrei caldera. Synthetic analysis shows that by adding a 3-axis digital compass to measure heading and tilt, along with kinematic GPS measurements, position of the anchor can be recovered to an accuracy of several centimeters or better, depending on water depth and GPS baseline length. Synthetic resolution tests show that our ability to detect shallow slow slip events on subduction plate boundaries can be greatly improved by adding offshore GPS-buoy sites.
Evolution of offshore wind waves tracked by surface drifters with a point-positioning GPS sensor
NASA Astrophysics Data System (ADS)
Komatsu, K.
2009-12-01
Wind-generated waves have been recognized as one of the most important factors of the sea surface roughness which plays crucial roles in various air-sea interactions such as energy, momentum, heat and gas exchanges. At the same time, wind waves with extreme wave heights representatively called as freak or rogue waves have been a matter of great concern for many people involved in shipping, fishing, constracting, surfing and other marine activities, because such extreme waves frequently affect on the marine activities and sometimes cause serious disasters. Nevertheless, investigations of actual conditions for the evolution of wind waves in the offshore region are less and sparse in contrast to dense monitoring networks in the coastal regions because of difficulty of offshore observation with high accuracy. Recently accurate in situ observation of offshore wind waves is getting possible at low cost owing to a wave height and direction sensor developed by Harigae et al. (2004) by installing a point-positioning GPS receiver on a surface drifting buoy. The point-positioning GPS sensor can extract three dimensional movements of the buoy excited by ocean waves with minimizing effects of GPS point-positioning errors through the use of a high-pass filter. Two drifting buoys equipped with the GPS-based wave sensor charged by solar cells were drifted in the western North Pacific and one of them continued to observe wind waves during 16 months from Sep. 2007. The RMSE of the GPS-based wave sensor was less than 10cm in significant wave height and about 1s in significant wave period in comparison with other sensors, i.e. accelerometers installed on drifting buoys of Japan Meteorological Agency, ultrasonic sensors placed at the Hiratsuka observation station of the University of Tokyo and altimeter of the JASON-1. The GPS-based wave buoys enabled us to detect freak waves defined as waves whose height is more than twice the significant wave height. The observation conducted by the wave buoys in 2007-2008 indicated a little more frequent occurrence of freak waves comparing with Forristall’s (1978) empirical formula and Naess’s (1985) distribution for a narrow-band Gaussian sea. Fig.1. Time series of the ratio of the significant wave height to the maximum wave height in 20 minutes sampling period observed by a drifting buoy with a GPS sensor
33 CFR 110.138 - Boston Harbor, Mass.
Code of Federal Regulations, 2012 CFR
2012-07-01
... line running due north from Old Harbor Buoy 4 to the shore line at City Point. (5) Explosives anchorage... beacon on top of the Boston Custom House tower; and thence to the point of beginning. (2) President Roads... adjacent land; on the east by a line between Castle Rocks Fog Signal Light and Old Harbor Shoal Buoy 2; on...
33 CFR 110.138 - Boston Harbor, Mass.
Code of Federal Regulations, 2013 CFR
2013-07-01
... line running due north from Old Harbor Buoy 4 to the shore line at City Point. (5) Explosives anchorage... beacon on top of the Boston Custom House tower; and thence to the point of beginning. (2) President Roads... adjacent land; on the east by a line between Castle Rocks Fog Signal Light and Old Harbor Shoal Buoy 2; on...
33 CFR 110.138 - Boston Harbor, Mass.
Code of Federal Regulations, 2014 CFR
2014-07-01
... line running due north from Old Harbor Buoy 4 to the shore line at City Point. (5) Explosives anchorage... beacon on top of the Boston Custom House tower; and thence to the point of beginning. (2) President Roads... adjacent land; on the east by a line between Castle Rocks Fog Signal Light and Old Harbor Shoal Buoy 2; on...
Seasonal Ice Zone Reconnaissance Surveys Coordination
2016-03-30
sea surface temperature (SST), sea level atmospheric pressure ( SLP ), and velocity (Steele), and dropsonde measurements of atmospheric properties...aircraft), cloud top/base heights UpTempO buoys for understanding and prediction…. Steele UpTempO buoy drops for SLP , SST, SSS, & surface velocity...reflectance, skin temperature, visible imagery AXCTD= Air Expendable CTD, AXCP= Air Expendable Current Profiler, SLP = Sea Level atmospheric
33 CFR 110.145 - Narragansett Bay, R.I.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Coasters Harbor Island, west of a line bearing 351° from Tracey Ledge Buoy 5 through Seventeen-foot Spot Buoy northeast of Gull Rocks; south of a line bearing 292° from the cupola at the Naval War College... bearing 341° from the outer end of Briggs Wharf to the southwestern shore of Coasters Harbor Island near...
33 CFR 110.145 - Narragansett Bay, R.I.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Coasters Harbor Island, west of a line bearing 351° from Tracey Ledge Buoy 5 through Seventeen-foot Spot Buoy northeast of Gull Rocks; south of a line bearing 292° from the cupola at the Naval War College... bearing 341° from the outer end of Briggs Wharf to the southwestern shore of Coasters Harbor Island near...
Wave and Current Observations in a Tidal Inlet Using GPS Drifter Buoys
2013-03-01
right panel). ............17 Figure 10. DWR-G external sensor configuration (left panel). GT-31 GPS receiver is visible on the bottom left. Two GoPro ...receiver is visible on the bottom left. Two GoPro cameras are attached to the top of the buoy. DWR-G internal sensor configuration (right panel
46 CFR 164.019-3 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Guard-approved PFDs. Commandant means the Chief of the Lifesaving and Fire Safety Division, Office of... code PFD type acceptable for use 1 I, II, and III. 2 II and III. 3 III. 4B IV (all Ring Buoys). 4BC IV (Buoyant Cushions). 4RB IV (Recreational Ring Buoys only). 5 Wearable Type V (intended use must be...
Subtropical Storm Alberto. NDBC Real-Time Data NDBC moored buoy, C-MAN, and drifting buoy data are available in real-time through selecting either: NDBC Station locator map: a series of regional maps which show : a tabular list of station identifiers. Real-time data are available for the last 45 days (at least
64. Photocopy of Buoy Derrick Arrangement, WAGL 543 and WAGL ...
64. Photocopy of Buoy Derrick Arrangement, WAGL 543 and WAGL 542. Puget Sound Naval Shipyard, Bremerton, Washington, Coast Guard Headquarters Drawing No. 540-WAGL-1701-20, dated April 1948. Original drawing property of the U.S. Coast Guard. - U.S. Coast Guard Cutter WHITE HEATH, USGS Integrated Support Command Boston, 427 Commercial Street, Boston, Suffolk County, MA
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 7310 (series) which is available from the District Budget Office of the appropriate Coast Guard District Commander. (b) Buoy and vessel use charges under this part are made for the cost or value of time... obstruction. No charge for time and expense of Coast Guard vessels is made when the marking of the obstruction...
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 7310 (series) which is available from the District Budget Office of the appropriate Coast Guard District Commander. (b) Buoy and vessel use charges under this part are made for the cost or value of time... obstruction. No charge for time and expense of Coast Guard vessels is made when the marking of the obstruction...
NASA Astrophysics Data System (ADS)
Lukovich, Jennifer V.; Geiger, Cathleen A.; Barber, David G.
2017-07-01
A framework is developed to assess the directional changes in sea ice drift paths and associated deformation processes in response to atmospheric forcing. The framework is based on Lagrangian statistical analyses leveraging particle dispersion theory which tells us whether ice drift is in a subdiffusive, diffusive, ballistic, or superdiffusive dynamical regime using single-particle (absolute) dispersion statistics. In terms of sea ice deformation, the framework uses two- and three-particle dispersion to characterize along- and across-shear transport as well as differential kinematic parameters. The approach is tested with GPS beacons deployed in triplets on sea ice in the southern Beaufort Sea at varying distances from the coastline in fall of 2009 with eight individual events characterized. One transition in particular follows the sea level pressure (SLP) high on 8 October in 2009 while the sea ice drift was in a superdiffusive dynamic regime. In this case, the dispersion scaling exponent (which is a slope between single-particle absolute dispersion of sea ice drift and elapsed time) changed from superdiffusive (α ˜ 3) to ballistic (α ˜ 2) as the SLP was rounding its maximum pressure value. Following this shift between regimes, there was a loss in synchronicity between sea ice drift and atmospheric motion patterns. While this is only one case study, the outcomes suggest similar studies be conducted on more buoy arrays to test momentum transfer linkages between storms and sea ice responses as a function of dispersion regime states using scaling exponents. The tools and framework developed in this study provide a unique characterization technique to evaluate these states with respect to sea ice processes in general. Application of these techniques can aid ice hazard assessments and weather forecasting in support of marine transportation and indigenous use of near-shore Arctic areas.
Accuracy of sea ice temperature derived from the advanced very high resolution radiometer
NASA Technical Reports Server (NTRS)
Yu, Y.; Rothrock, D. A.; Lindsay, R. W.
1995-01-01
The accuracy of Arctic sea ice surface temperatures T(sub s) dericed from advanced very high resolution radiometer (AVHRR) thermal channels is evaluated in the cold seasons by comparing them with surface air temperatures T(sub air) from drifting buoys and ice stations. We use three different estimates of satellite surface temperatures, a direct estimate from AVHRR channel 4 with only correction for the snow surface emissivity but not for the atmosphere, a single-channel regression of T(sub s) with T(sub air), and Key and Haefliger's (1992) polar multichannel algorithm. We find no measurable bias in any of these estimates and few differences in their statistics. The similar performance of all three methods indicates that an atmospheric water vapor correction is not important for the dry winter atmosphere in the central Arctic, given the other sources of error that remain in both the satellite and the comparison data. A record of drifting station data shows winter air temperature to be 1.4 C warmer than the snow surface temperature. `Correcting' air temperatures to skin temperature by subtracting this amount implies that satellite T(sub s) estimates are biased warm with respect to skin temperature by about this amount. A case study with low-flying aircraft data suggests that ice crystal precipitation can cause satellite estimates of T(sub s) to be several degrees warmer than radiometric measurements taken close to the surface, presumably below the ice crystal precipitation layer. An analysis in which errors are assumed to exist in all measurements, not just the satellite measurements, gives a standard deviation in the satellite estimates of 0.9 C, about half the standard deviation of 1.7 C estimated by assigning all the variation between T(sub s) and T(sub air) to errors in T(sub s).
NASA Astrophysics Data System (ADS)
Stanton, T. P.; Shaw, W. J.
2016-02-01
Drainage of surface melt pond water into the top of the ocean mixed layer is seen widely in the Arctic ice pack in later summer (for example Gallaher et al 2015). Under calm conditions, this fresh water forms a thin, stratified layer immediately below the ice which is dynamically decoupled from the thicker, underlying seasonal mixed layer by the density difference between the two layers. The ephemeral surface layer is significantly warmer than the underlying ocean water owing to the higher freezing temperature of the fresh melt water. How the presence of this warm ephemeral layer enhances basal melt rate and speeds the destruction of the floes is investigated. High resolution timeseries measurements of T/S profiles in the 2m of the ocean immediately below the ice, and eddy-correlation fluxes of heat, salt and momentum 2.5m below the ice were made from an Autonomous Ocean Flux Buoy over a 2 month interval in later summer of 2015 as a component of the ONR Marginal Ice Zone project. The stratification and turbulent forcing observations are used with a 1 D turbulence closure model to understand how momentum and incoming radiative energy are stored and redistributed within the ephemeral layer. Under low wind forcing conditions both turbulent mixing energy and the water with high departure from freezing are trapped in the ephemeral layer by the strong density gradient at the base of the layer, resulting in rapid basal melting. This case is contrasted with model runs where the ephemeral layer heat is allowed to mix across the seasonal mixed layer, which results in slower basal melt rates. Consequently, the salinity-trapped warm ephemeral layer results in the formation of more open water earlier in the summer season, in turn resulting in increased cumulative heating of the ocean mixed layer, enhancing ice/ocean albedo feedbacks.
NASA Astrophysics Data System (ADS)
Holt, B.; Jones, C. E.; Brekke, C.; Breivik, O.; Skrunes, S.; Espeseth, M.
2016-02-01
A targeted experiment in characterizing the properties and development of mineral oil slicks was undertaken by NASA, UiT - The Arctic University of Norway, and the Norwegian Meteorological Institute during the 2015 Norwegian oil-on-water spill exercise in the North Sea (OPV2015). NORSE2015 (Norwegian Radar oil Spill Experiment) involved controlled release of plant oil and mineral emulsions of three different oil-to-water ratios, imaging of the slicks with satellite-borne synthetic aperture radars (SAR), and tracking their development with the NASA-UAVSAR instrument over a period of eight hours following release. During the experiment, in situ measurements were made from ship or aircraft with meteorological instruments, released drift buoys, and optical/IR imagers. The experiment was designed to provide validation data for development of a physical model relating polarization-dependent electromagnetic scattering to the dielectric properties of oil mixed with ocean water in a thick slick or emulsion. UAVSAR is a particularly low noise instrument, which enables detection of oil characteristics, and serves as the basis for a relative comparison of different radar frequencies and instruments in oil slick detection and characterization. The time series of UAVSAR polarimetric SAR (PolSAR) is used to track the spreading, movement, and change in backscatter of the different emulsion slicks and the plant oil, to look at movement relative to wind and wave directions, and to develop methods to differentiate between biogenic and mineral slicks based upon temporal changes in the slicks, including environment-driven changes. In this presentation, the experiment will be described and preliminary results presented. This work was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. The Norwegian experiment was partly financed by CIRFA - Centre for integrated remote sensing and forecasting for arctic operations.
NASA Astrophysics Data System (ADS)
Boyle, J. P.
2016-02-01
Results from a surface contact drifter buoy which measures near-surface conductivity ( 10 cm depth), sea state characteristics and near-surface water temperature ( 2 cm depth) are described. This light (< 750 gram), wave-following discus buoy platform has a hull diameter of 25 cm and a thickness of approximately 3 cm. The buoy is designed to allow for capsize events, but remains top up because it is ballasted for self-righting. It has a small above-surface profile and low windage, resulting in near-Lagrangian drift characteristics. It is autonomous, with low power requirements and solar panel battery recharging. Onboard sensors include an inductive toroidal conductivity probe for salinity measurement, a nine-degrees-of-freedom motion package for derivation of directional wave spectra and a thermocouple for water temperature measurement. Data retrieval for expendable, ocean-going operation uses an onboard Argos transmitter. Scientific results as well as data processing algorithms are presented from laboratory and field experiments which support qualification of buoy platform measurements. These include sensor calibration experiments, longer-term dock-side biofouling experiments during 2013-2014 and a series of short-duration ocean deployments in the Gulf Stream in 2014. In addition, a treatment method will be described which appears to minimize the effects of biofouling on the inductive conductivity probe when in coastal surface waters. Due to its low cost and ease of deployment, scores, perhaps hundreds of these novel instruments could be deployed from ships or aircraft during process studies or to provide surface validation for satellite-based measurements, particularly in high precipitation regions.
NASA Astrophysics Data System (ADS)
Knap, A. H.; Chapman, P.; DiMarco, S. F.; Walpert, J.; Guinasso, N. L., Jr.; Whilden, K.
2016-02-01
The Gulf of Mexico (GOM), sometimes referred to as the western Mediterranean, is a dynamic and interesting body for study with diverse uses and needs from a wide range of communities. Environmental issues are similar to many other semi-closed basins and the main ones, nutrient and chemical discharge, land run-off and physical currents, as well as oil spills and the many natural seeps creates many issues such as eutrophication, an annual hypoxic zone, Harmful Algal blooms, ocean acidification and oil blowouts to name a few. The Texas Automated Buoy System is constituted of 8 real time coastal buoys operated by the Geochemical and Environmental Research Group. Through a JIP, 2 additional buoys were added at the Flower Garden Banks. to support decision-making should there be a spill. In addition a numerical circulation modeling group at Texas A&M University Oceanography Department was also funded to connect the data from the buoys to a predictive model also funded by TGLO. This observing system has proved its worth over the years as spills have occurred which have been tracked for rapid and effective coastal protection. Recently, other instrumentation has been developed to more holistically study the Gulf of Mexico and particularly the Texas Coast. Eight 5-Hz coastal radars spaced approximated 80 km along the coast are being installed from South Padre Island to the Sabine. Autonomous Surface Vehicles (Autonaut and Liquid Robotics Wave Gliders) will complement the buoy network and coastal radars by establishing a series of transects that will transit through out the observational footprint. The first data emerging from this integration will be presented.
Real-time seismic data from the coastal ocean
Frye, D.; ten Brink, Uri S.; Paul, W.; Peal, K.; Von Der Heydt, K.
2003-01-01
A moored-buoy system for collecting real-time seismic data from the coastal ocean has been developed and will be deployed for its initial field trial in the fall of 2003. The key component in this moored system is an ultra-stretchy mooring hose that provides compliance for waves and currents and protects the electrical conductors connecting an Ocean Bottom Seismometer (OBS) to a surface buoy from the effects of bending and stretching. This hose is able to stretch to more than twice its unstretched length of 30 m without putting excessive strain on the electrical conductors embedded in its wall. In the initial trials of this system, the OBS will be deployed on the bottom in 40 m of water and connected to the mooring hose through a cable on the seafloor. It will transmit continuous data at a rate of about 5,000 bps to a radio link in the surface buoy. A repeater modem located at the Gay Head lighthouse on Martha's Vineyard about 18 km from the mooring site will receive the transmissions and forward the data to our laboratory at WHOI, about 46 km distant. A GPS receiver on the surface buoy will be configured to send accurate and synchronized time to the OBS on the seafloor, which will make it possible to include data from these undersea systems in the existing seismic data network without the need for any preprocessing. Power to operate the RF link and the OBS will be supplied by solar panels and rechargeable batteries on the surface buoy.
Mobile data buoy system. [water quality measurements in watersheds and Mobile Bay, Alabama
NASA Technical Reports Server (NTRS)
Morton, R. A.
1975-01-01
The Mobile Data Buoy System was conceived to serve the users requirement for obtaining water quality parameters from two separate watershed systems. In view of the cost constraints of the ERTS program it was obvious that the network of 10 sampling stations required could not be of the fixed installation type; therefore, it was decided to go to a system of battery powered buoys of a size that could be used in one watershed system for a period of time and then moved to another by use of a relatively small 6.7 m (22 foot) boat. The basic idea of the water quality measurement program was to establish the water quality pattern of change from the headwaters of the watersheds to and through the Mobile Bay. This would allow the investigator to develop a good picture of the state's major water resources and the pressures from pollution that are being imposed. At this point in deployment of this mobile system of buoys, it is too early to put a quantitative value on the system, however it appears less expensive than known fixed installations as to first cost. It has a basic advantage in that it can be moved, at very little expense, to alternate sites where it is desired to obtain water quality data. It is to be noted this buoy system which covers a 80 Km (50 mile) stretch of the Black Warrior River and then skips down 483 Km (300 miles) to Mobile Bay for the next measurements would not be feasible unless there is a satellite to collect and relay the data.
Wave-Ice and Air-Ice-Ocean Interaction During the Chukchi Sea Ice Edge Advance
2014-09-30
During cruise CU-B UAF UW Airborne expendable Ice Buoy (AXIB) Ahead, at and inside ice edge Surface meteorology T, SLP ~1 year CU-B UW...Balance (IMB) buoys Inside ice edge w/ >50cm thickness Ice mass balance T in snow-ice-ocean, T, SLP at surface ~1 year WHOI CRREL (SeaState DRI
In-situ and Land-Based Remote Sensing of River Inlets and Their Interaction with Coastal Waters
2013-09-30
CDIP buoy 190 was reporting the impending waves having a 1 meter significant wave height, 7.7s peak period, from 129 degrees. Using the X-Band...spectral energy along a shifted dispersion relationship curve. In deep water, the waves reported by CDIP buoy 190 would have a wavenumber of 0.068 rad/m
33 CFR 110.145 - Narragansett Bay, R.I.
Code of Federal Regulations, 2010 CFR
2010-07-01
... bearing 351° from Tracey Ledge Buoy 5 through Seventeen-foot Spot Buoy northeast of Gull Rocks; south of a line bearing 292° from the cupola at the Naval War College; east of a line ranging 19° from the... stakes will not be allowed. (4) Anchorage D. West of Goat Island, south of a line bearing 247° from...
33 CFR 110.145 - Narragansett Bay, R.I.
Code of Federal Regulations, 2011 CFR
2011-07-01
... bearing 351° from Tracey Ledge Buoy 5 through Seventeen-foot Spot Buoy northeast of Gull Rocks; south of a line bearing 292° from the cupola at the Naval War College; east of a line ranging 19° from the... stakes will not be allowed. (4) Anchorage D. West of Goat Island, south of a line bearing 247° from...
33 CFR 110.145 - Narragansett Bay, R.I.
Code of Federal Regulations, 2012 CFR
2012-07-01
... bearing 351° from Tracey Ledge Buoy 5 through Seventeen-foot Spot Buoy northeast of Gull Rocks; south of a line bearing 292° from the cupola at the Naval War College; east of a line ranging 19° from the.... (5) Anchorage E. South of Coasters Harbor Island, east of a line bearing 341° from the outer end of...
Satellite Communications for Coast Guard Homeland Defense
2002-03-01
WAN Wide Area Network WHEC High Endurance Cutter WIX Training Cutter WLB Seagoing Buoy Tenders WLI Inland Buoy Tenders WLIC...WMEC), Icebreakers (WAGB), and the Training Cutter ( WIX ) 9 MILSATCOM (UHF) Secure Voice, Record Message Traffic, Tactical data (OTIXICS...onboard CG vessels. [Ref. 3, p.19] By supporting different platforms throughout the CG fleet, we increase the complexity of the network, and thus
76 FR 50710 - Security Zones; Cruise Ships, San Pedro Bay, CA
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-16
... located within the San Pedro Bay port area landward of the sea buoys bounding the Port of Los Angeles or... port area landward of the sea buoys bounding the Port of Los Angeles or Port of Long Beach or at... authorized by the Captain of the Port (COTP) Los Angeles--Long Beach, or his designated representative. DATES...
Quantifying Electromagnetic Wave Propagation Environment Using Measurements From A Small Buoy
2017-06-01
ELECTROMAGNETIC WAVE PROPAGATION ENVIRONMENT USING MEASUREMENTS FROM A SMALL BUOY by Andrew E. Sweeney June 2017 Thesis Advisor: Qing Wang...TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE QUANTIFYING ELECTROMAGNETIC WAVE PROPAGATION ENVIRONMENT USING MEASUREMENTS FROM A...the Coupled Air Sea Processes and Electromagnetic (EM) ducting Research (CASPER), to understand air-sea interaction processes and their representation
Code of Federal Regulations, 2013 CFR
2013-07-01
..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi River and Southwest Pass, moving security zones are established around all cruise ships between the... encompass all waters within 500 yards of a cruise ship. These zones remain in effect during the entire...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety Zone; Large Cruise Ships... Areas and Limited Access Areas Eighth Coast Guard District § 165.839 Safety Zone; Large Cruise Ships; Lower Mississippi River, Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location...
Code of Federal Regulations, 2011 CFR
2011-07-01
..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi River and Southwest Pass, moving security zones are established around all cruise ships between the... encompass all waters within 500 yards of a cruise ship. These zones remain in effect during the entire...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety Zone; Large Cruise Ships... Areas and Limited Access Areas Eighth Coast Guard District § 165.839 Safety Zone; Large Cruise Ships; Lower Mississippi River, Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location...
Code of Federal Regulations, 2014 CFR
2014-07-01
..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi River and Southwest Pass, moving security zones are established around all cruise ships between the... encompass all waters within 500 yards of a cruise ship. These zones remain in effect during the entire...
Code of Federal Regulations, 2012 CFR
2012-07-01
..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi River and Southwest Pass, moving security zones are established around all cruise ships between the... encompass all waters within 500 yards of a cruise ship. These zones remain in effect during the entire...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-31
... Marker 96.0; New Orleans, LA AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: The Coast Guard is... the Port of New Orleans Cruise Ship Terminal, mile marker 96.0, and the Southwest Pass Sea Buoy. The... Commander (LCDR) Brandon Sullivan, Sector New Orleans, U.S. Coast Guard; telephone 504-365-2280, email...
33 CFR 165.704 - Safety Zone; Tampa Bay, Florida.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., Florida. (a) A floating safety zone is established consisting of an area 1000 yards fore and aft of a... ending at Gadsden Point Cut Lighted Buoys “3” and “4”. The safety zone starts again at Gadsden Point Cut... the marked channel at Tampa Bay Cut “K” buoy “11K” enroute to Rattlesnake, Tampa, FL, the floating...
The Antifouling of ACLW-CAR Based on Ultrasonic Cleaner
NASA Astrophysics Data System (ADS)
Zhang, Guohua; Liu, Shixuan; Qin, Qingliang
2017-10-01
Equipped with ACLW-CAR, the buoy provided effective technical platform for on-site rapid monitoring of the chlorophyll and turbidity. Performance index and usage in the ocean buoy of ACLW-CAR was introduced. Ultrasonic cleaning method in seawater was developed for preventing ACLW-CAR from biofouling. Marine chlorophyll and turbidity data can serve for oceanographic research and marine resource exploitation.
46 CFR 7.45 - Cape Henlopen, DE to Cape Charles, VA.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Inlet Lighted Gong Buoy “1”); thence to Indian River Inlet South Jetty Light. (b) A line drawn from... Buoy “5”); thence to the easternmost extremity of the south breakwater. (c) A line drawn from... from the southernmost extremity of Cedar Island to latitude 37°34.7′ N. longitude 75°36.0′ W...
Fort Morgan and the Battle of Mobile Bay. Teaching with Historic Places.
ERIC Educational Resources Information Center
Blankenship, Blanton; Rambo, Bill
Under the light of dawn, Union Admiral David Farragut began his attack on Mobile Bay, Alabama. Aware of the danger near Fort Morgan (Alabama), Farragut ordered his captains to stay to the eastward of the easternmost buoy because it was understood there were obstructions between the buoys. The ironclad USS Tecumseh, unable to avoid the danger,…
A Low-Cost Sensor Buoy System for Monitoring Shallow Marine Environments
Albaladejo, Cristina; Soto, Fulgencio; Torres, Roque; Sánchez, Pedro; López, Juan A.
2012-01-01
Monitoring of marine ecosystems is essential to identify the parameters that determine their condition. The data derived from the sensors used to monitor them are a fundamental source for the development of mathematical models with which to predict the behaviour of conditions of the water, the sea bed and the living creatures inhabiting it. This paper is intended to explain and illustrate a design and implementation for a new multisensor monitoring buoy system. The system design is based on a number of fundamental requirements that set it apart from other recent proposals: low cost of implementation, the possibility of application in coastal shallow-water marine environments, suitable dimensions for deployment and stability of the sensor system in a shifting environment like the sea bed, and total autonomy of power supply and data recording. The buoy system has successfully performed remote monitoring of temperature and marine pressure (SBE 39 sensor), temperature (MCP9700 sensor) and atmospheric pressure (YOUNG 61302L sensor). The above requirements have been satisfactorily validated by operational trials in a marine environment. The proposed buoy sensor system thus seems to offer a broad range of applications. PMID:23012562
NASA Astrophysics Data System (ADS)
Aoyama, Yuichi; Kim, Tae-Hee; Doi, Koichiro; Hayakawa, Hideaki; Higashi, Toshihiro; Ohsono, Shingo; Shibuya, Kazuo
2016-06-01
A dual-frequency GPS receiver was deployed on a floating iceberg downstream of the calving front of Shirase Glacier, East Antarctica, on 28 December 2011 for utilizing as floating buoy. The three-dimensional position of the buoy was obtained by GPS every 30 s with a 4-5-cm precision for ca. 25 days. The height uncertainty of the 1-h averaged vertical position was ∼0.5 cm, even considering the uncertainties of un-modeled ocean loading effects. The daily evolution of north-south (NS), east-west (EW), and up-down (UD) motions shows periodic UD variations sometimes attaining an amplitude of 1 m. Observed amplitudes of tidal harmonics of major constituents were 88%-93% (O1) and 85%-88% (M2) of values observed in the global ocean tide models FES2004 and TPXO-8 Atlas. The basal melting rate of the iceberg is estimated to be ∼0.6 m/day, based on a firn densification model and using a quasi-linear sinking rate of the iceberg surface. The 30-s sampling frequency geodetic-mode GPS buoy helps to reveal ice-ocean dynamics around the calving front of Antarctic glaciers.
East Spar development: NCC buoy--The vertical submarine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boyle, E.C.
1998-02-01
The remote East Spar gas/condensate field has been developed using a subsea production system operated by an unmanned navigation, communication, and control (NCC) buoy. The use of this type of system allows control of the field from any convenient location, with the command-response time and the cost of the facility almost completely independent of the distance to the shore or host facility. Successes during the project (such as using model tests to prove the concept and using a tension-leg mooring system to reduce the motion response of the buoy) are discussed and compared to failures, like the weight and sizemore » growth of the structure, caused as the design requirements were finalized and external factors changed. The operation and layout of this facility is summarized, showing why it was described as a vertical submarine. Conclusions are drawn about the use of an NCC buoy to develop this field, showing that the main objectives have been achieved. The limited operating experience to date is also considered in the review of the design objectives. The paper concludes with the possibilities for the future of this type of concept.« less
NASA Astrophysics Data System (ADS)
Mahura, A. G.; Baklanov, A. A.
2003-10-01
The probabilistic analysis of atmospheric transport patterns from most important nuclear risk sites in the Euro-Arctic region is performed employing the methodology developed within the "Arctic Risk" Project of the NARP Programme (Baklanov and Mahura, 2003). The risk sites are the nuclear power plants in the Northwest Russia, Finland, Sweden, Lithuania, United Kingdom, and Germany as well as the Novaya Zemlya test site of Russia. The geographical regions of interest are the Northern and Central European countries and Northwest Russia. In this study, the employed research tools are the trajectory model to calculate a multiyear dataset of forward trajectories that originated over the risk site locations, and a set of statistical methods (including exploratory, cluster, and probability fields analyses) for analysis of trajectory modelling results. The probabilistic analyses of trajectory modelling results for eleven sites are presented as a set of various indicators of the risk sites possible impact on geographical regions and countries of interest. The nuclear risk site possible impact (on a particular geographical region, territory, country, site, etc.) due to atmospheric transport from the site after hypothetical accidental release of radioactivity can be properly estimated based on a combined interpretation of the indicators (simple characteristics, atmospheric transport pathways, airflow and fast transport probability fields, maximum reaching distance and maximum possible impact zone, typical transport time and precipitation factor fields) for different time periods (annual, seasonal, and monthly) for any selected site (both separately for each site or grouped for several sites) in the Euro-Arctic region. Such estimation could be the useful input information for the decision-making process, risk assessment, and planning of emergency response systems for sites of nuclear, chemical, and biological danger.
Scale model testing of drogues for free drifting buoys
NASA Technical Reports Server (NTRS)
Vachon, W. A.
1973-01-01
Instrumented model drogue tests were conducted in a ship model towing tank. The purpose of the tests was to observe and measure deployment and drag characteristics of such shapes as parachutes, crossed vanes, and window shades which may be employed in conjunction with free drifting buoys. Both Froude and Reynolds scaling laws were applied while scaling to full scale relative velocities of from 0 to 0.2 knots. A weighted window shade drogue is recommended because of its performance, high drag coefficient, simplicity, and low cost. Detailed theoretical performance curves are presented for parachutes, crossed vanes, and window shade drogues. Theoretical estimates of depth locking accuracy and buoy-induced dynamic loads pertinent to window shade drogues are presented as a design aid. An example of a window shade drogue design is presented.
DRIFTER Web App Development Support
NASA Technical Reports Server (NTRS)
Davis, Derrick D.; Armstrong, Curtis D.
2015-01-01
During my 2015 internship at Stennis Space Center (SSC) I supported the development of a web based tool to enable user interaction with a low-cost environmental monitoring buoy called the DRIFTER. DRIFTERs are designed by SSC's Applied Science and Technology Projects branch and are used to measure parameters such as water temperature and salinity. Data collected by the buoys help verify measurements by NASA satellites, which contributes to NASA's mission to advance understanding of the Earth by developing technologies to improve the quality of life on or home planet. My main objective during this internship was to support the development of the DRIFTER by writing web-based software that allows the public to view and access data collected by the buoys. In addition, this software would enable DRIFTER owners to configure and control the devices.
The Greenland Sea Odden: Intra- and inter-annual variability
Russell, C.A.; Fischer, K.W.; Shuchman, R.A.; Josberger, E.G.
1997-01-01
The "Odden" is a large sea ice feature that forms in the East Greenland Sea which generally forms at the beginning of the winter season and can cover 300,000 km2. Throughout the winter, the outer edge of the Odden may advance and retreat by several hundred kilometers on time scales of a few days to weeks. Satellite passive microwave observations from 1978 through 1995 provide a continuous record of the spatial and temporal variations of this extremely dynamic phenomenon. The 17 year record shows both strong inter- and intra-annual variations in Odden extent and temporal behavior. An analysis of the satellite passive microwave derived ice area and extent time series along with meteorological data from the Arctic Drifting Buoy Network determined the meteorological forcing required for Odden growth, maintenance and decay. The key meteorological parameters which cause the rapid ice formation and decay associated with the Odden are, in order of importance, air temperature, wind speed, and wind direction. Atmospheric pressure was found not to play a significant role in the Odden events. Air temperature and wind direction are the dominant variables with temperatures below -9.5??C and winds from the west required to trigger significant Odden ice formation events. ??2004 Copyright SPIE - The International Society for Optical Engineering.
Satellite/Submarine Arctic Sea Ice Remote Sensing in 2004 and 2007
NASA Astrophysics Data System (ADS)
Hughes, N. E.; Wadhams, P.; Rodrigues, J.
2007-12-01
After an interlude of 8 years the U.K. Royal Navy returned to the Arctic Ocean with an under-ice mission by the submarine shape HMS Tireless in April 2004. A full environmental monitoring programme in which U.K. civilian scientists were allowed to participate was integrated into the mission. This was subsequently followed by a second expedition, in March 2007, which allowed further measurements to be acquired. These have so far been the only opportunities for civilian scientists to utilise navy submarines in the Arctic since the demise of the U.S. SCICEX programme in 2000. This paper presents some of the data collected on these new missions and uses it for validation of sea ice information derived from coincident acquisitions by modern satellite sensors such as the ESA Envisat ASAR and NASA MODIS. In both the 2004 and 2007 expeditions shape Tireless took a track north of Greenland along the latitude 85° N. This was similar to the route used for an earlier submarine-aircraft combined survey in April 1987 with which our results shall be compared. In all three missions the submarine was equipped with a standard upward-looking echosounder and sidescan for ice observations and a full range of satellite-borne, or airborne in the case of the earlier mission, microwave and optical sensors were available for validation. In this study we concentrate on the submarine track north of Greenland from the Marginal Ice Zone (MIZ) in Fram Strait through to the Lincoln Sea around 65° W. This transect encompasses a wide range of differing sea ice conditions, from the highly mobile mixture of first year and multi year ice being transported on the trans-polar drift through to the highly deformed ice north of Greenland and Ellesmere Island. The combination of submarine measurements of ice thickness and satellite/aircraft top-side measurements gives an accurate indication of how changes in the ice regime are taking place and allows the potential development of multi-sensor data fusion algorithms for improved sea ice classification and estimation of thickness.
Arctic sea ice area in CMIP3 and CMIP5 climate model ensembles - variability and change
NASA Astrophysics Data System (ADS)
Semenov, V. A.; Martin, T.; Behrens, L. K.; Latif, M.
2015-02-01
The shrinking Arctic sea ice cover observed during the last decades is probably the clearest manifestation of ongoing climate change. While climate models in general reproduce the sea ice retreat in the Arctic during the 20th century and simulate further sea ice area loss during the 21st century in response to anthropogenic forcing, the models suffer from large biases and the model results exhibit considerable spread. The last generation of climate models from World Climate Research Programme Coupled Model Intercomparison Project Phase 5 (CMIP5), when compared to the previous CMIP3 model ensemble and considering the whole Arctic, were found to be more consistent with the observed changes in sea ice extent during the recent decades. Some CMIP5 models project strongly accelerated (non-linear) sea ice loss during the first half of the 21st century. Here, complementary to previous studies, we compare results from CMIP3 and CMIP5 with respect to regional Arctic sea ice change. We focus on September and March sea ice. Sea ice area (SIA) variability, sea ice concentration (SIC) variability, and characteristics of the SIA seasonal cycle and interannual variability have been analysed for the whole Arctic, termed Entire Arctic, Central Arctic and Barents Sea. Further, the sensitivity of SIA changes to changes in Northern Hemisphere (NH) averaged temperature is investigated and several important dynamical links between SIA and natural climate variability involving the Atlantic Meridional Overturning Circulation (AMOC), North Atlantic Oscillation (NAO) and sea level pressure gradient (SLPG) in the western Barents Sea opening serving as an index of oceanic inflow to the Barents Sea are studied. The CMIP3 and CMIP5 models not only simulate a coherent decline of the Arctic SIA but also depict consistent changes in the SIA seasonal cycle and in the aforementioned dynamical links. The spatial patterns of SIC variability improve in the CMIP5 ensemble, particularly in summer. Both CMIP ensembles depict a significant link between the SIA and NH temperature changes. Our analysis suggests that, on average, the sensitivity of SIA to external forcing is enhanced in the CMIP5 models. The Arctic SIA variability response to anthropogenic forcing is different in CMIP3 and CMIP5. While the CMIP3 models simulate increased variability in March and September, the CMIP5 ensemble shows the opposite tendency. A noticeable improvement in the simulation of summer SIA by the CMIP5 models is often accompanied by worse results for winter SIA characteristics. The relation between SIA and mean AMOC changes is opposite in September and March, with March SIA changes being positively correlated with AMOC slowing. Finally, both CMIP ensembles demonstrate an ability to capture, at least qualitatively, important dynamical links of SIA to decadal variability of the AMOC, NAO and SLPG. SIA in the Barents Sea is strongly overestimated by the majority of the CMIP3 and CMIP5 models, and projected SIA changes are characterized by a large spread giving rise to high uncertainty.
33 CFR 162.132 - Connecting waters from Lake Huron to Lake Erie; communications rules.
Code of Federal Regulations, 2011 CFR
2011-07-01
... monitor: (1) Channel 11 (156.55 mhz) between Lake Huron Cut Lighted Buoy 11 and Lake St. Clair Light; and (2) Channel 12 (156.60 mhz) between Lake St. Clair Light and Detroit River Light. (b) Radiotelephone... Cut Light “7” Lake Huron Cut Lighted Buoy “1” Report. Report St. Clair/Black River Junction Light...
Seasonal Ice Zone Reconnaissance Surveys Coordination
2014-09-30
profiler (AXCP) ocean velocity shear (Morison), UpTempO buoy measurements of sea surface temperature (SST), sea level atmospheric pressure ( SLP ), and...and prediction…. Steele UpTempO buoy drops for SLP , SST, SSS, & surface velocity Visible and Thermal Images of the SIZ from the Coast Guard...Expendable CTD, AXCP= Air Expendable Current Profiler, SLP = Sea Level atmospheric Pressure, SST= Seas Surface Temperature, A/C= aircraft, SIC=Sea Ice
Nearshore Sea Clutter Measurements from a Fixed Platform
2012-04-01
Water (MLL W) datum. 7. GPS Two differential GPS units, Magellan ProMark 3.0, were utilized to determine precise differences in position between the...8 Figure 8. (a) Trihedral configuration on the small boat and position of the GPS and IMU sensors. (b) Profile view of...SIO Miniature Directional Wave Buoys The Scripps Institution of Oceanography designs and manufactures GPS -based miniature directional wave buoys
1993-03-01
Meteorological instrumentation was mounted to both the discus and toroid buoys. A two I part aluminum tower was attached to both buoy types. The top...Temperature Thermistor -5 to +300C 1/2 time average Thermometrics Measured during first 4K @ 25 0 C half of avg. period. Air Temperature Thermistor -10
The Moored Acoustic Buoy System (MABS)
1975-04-04
STAQOG, Ocean Sciences & Technology Department Indirect. REVIEWED AND APPROY 4 April lq75 A)R. Hse Associate Director for Sonar Retsearch The authors...It consists of a subsurface instrumentation buoy in conjunction with a family of lightweight hydrophone arrays designed to measure a variety of...vertical to horizontal in the water column. Recent de- velopments in lightweight synthetic-cable technology have been incorporated into the design to make
33 CFR 110.140 - Buzzards Bay, Nantucket Sound, and adjacent waters, Mass.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Phoenix Point; thence 154° along a line which passes 100 yards east of New Bedford Channel Buoys 8, 6, and... through Bird Island Reef Bell Buoy 13; and south of a line bearing 270° from Wings Neck Light. Each vessel... Island Channel 4 Light; thence 129° to a point bearing 209°, approximately 733 yards, from Wings Neck...
33 CFR 110.140 - Buzzards Bay, Nantucket Sound, and adjacent waters, Mass.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Phoenix Point; thence 154° along a line which passes 100 yards east of New Bedford Channel Buoys 8, 6, and... through Bird Island Reef Bell Buoy 13; and south of a line bearing 270° from Wings Neck Light. Each vessel... Island Channel 4 Light; thence 129° to a point bearing 209°, approximately 733 yards, from Wings Neck...
33 CFR 110.140 - Buzzards Bay, Nantucket Sound, and adjacent waters, Mass.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Phoenix Point; thence 154° along a line which passes 100 yards east of New Bedford Channel Buoys 8, 6, and... through Bird Island Reef Bell Buoy 13; and south of a line bearing 270° from Wings Neck Light. Each vessel... Island Channel 4 Light; thence 129° to a point bearing 209°, approximately 733 yards, from Wings Neck...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jens Korsgaard
The main conclusions from the work carried out under this contract are: An ordinary seafarer can learn by training on a simulator, to moor large tanker vessels to the Hydrostatic Mooring, safely and quickly, in all weather conditions up to storms generating waves with a significant wave height of 8 m. Complete conceptual design of the Hydrostatic Mooring buoy was carried out which proved that the buoy could be constructed entirely from commercially available standard components and materials. The design is robust, and damage resistant. The mooring tests had a 100% success rate from the point of view of themore » buoy being securely attached and moored to the vessel following every mooring attempt. The tests had an 80% success rate from the point of view of the buoy being adequately centered such that petroleum transfer equipment on the vessel could be attached to the corresponding equipment on the buoy. The results given in Table 3-2 of the mooring tests show a consistently improving performance from test to test by the Captain that performed the mooring operations. This is not surprising, in view of the fact that the Captain had only three days of training on the simulator prior to conducting the tests, that the maneuvering required is non-standard, and the test program itself lasted four days. One conclusion of the test performance is that the Captain was not fully trained at the initiation of the test. It may therefore be concluded that a thoroughly trained navigator would probably be able to make the mooring such that the fluid transfer equipment can be connected with reliability in excess of 90%. Considering that the typical standard buoy has enough power aboard to make eight mooring attempts, this implies that the probability that the mooring attempt should fail because of the inability to connect the fluid transfer equipment is of the order of 10{sup {minus}8}. It may therefore be concluded that the mooring operation between a Hydrostatic Mooring and a large tanker vessel can be carried out with near absolute reliability in all sea states up to a sea state where the significant wave height is 8 m.« less
NASA Astrophysics Data System (ADS)
Komatsu, Kosei
Wind-generated waves have been recognized as one of the most important factors of the sea surface roughness which plays crucial roles in various air-sea interactions such as energy, mo-mentum, heat and gas exchanges. At the same time, wind waves with extreme wave heights representatively called as freak or rogue waves have been a matter of great concern for many people involved in shipping, fishing, constracting, surfing and other marine activities, because such extreme waves frequently affect on the marine activities and sometimes cause serious dis-asters. Nevertheless, investigations of actual conditions for the evolution of wind waves in the offshore region are less and sparse in contrast to dense monitoring networks in the coastal re-gions because of difficulty of offshore observation with high accuracy. Recently accurate in situ observation of offshore wind waves is getting possible at low cost owing to a wave height and di-rection sensor developed by Harigae et al. (2004) by installing a point-positioning GPS receiver on a surface drifting buoy. The point-positioning GPS sensor can extract three dimensional movements of the buoy excited by ocean waves with minimizing effects of GPS point-positioning errors through the use of a high-pass filter. Two drifting buoys equipped with the GPS-based wave sensor charged by solar cells were drifted in the western North Pacific and one of them continued to observe wind waves during 16 months from Sep. 2007. The RMSE of the GPS-based wave sensor was less than 10cm in significant wave height and about 1s in significant wave period in comparison with other sensors, i.e. accelerometers installed on drifting buoys of Japan Meteorological Agency, ultrasonic sensors placed at the Hiratsuka observation station of the University of Tokyo and altimeter of the JASON-1. The GPS-based wave buoys enabled us to detect freak waves defined as waves whose height is more than twice the significant wave height. The observation conducted by the wave buoys in 2007-2008 indicated a little more frequent occurrence of freak waves comparing with Forristall's (1978) empirical formula and Naess's (1985) distribution for a narrow-band Gaussian sea.
NASA Astrophysics Data System (ADS)
De Carlo, E. H.; Drupp, P. S.; Thompson, R. W.; Mackenzie, F. T.; Muscielewicz, S.; Jones, S. M.; Feely, R. A.; Sabine, C. L.
2012-12-01
A series of MAP-CO2 buoys deployed in the coastal waters of Hawaii have produced multiyear high temporal resolution CO2 records in four different coral reef environments of the island of Oahu, Hawaii. This study is part of an integrated effort to understand the factors that influence the dynamics of CO2-carbonic acid system parameters in waters bathing Pacific high island coral reef ecosystems and subject to differing natural and anthropogenic stresses. The MAP-CO2 buoys are located in backreef, lagoonal, and fringing reef sites, and measure CO2 and O2 in seawater and in the atmosphere. Other sensors on the buoys record physical and biogeochemical parameters (CTD, chl-a, turbidity, pH, nitrate). The buoy records, when combined with data from synoptic spatial sampling, have allowed us to examine the interplay between biological cycles of productivity/respiration and calcification/dissolution and biogeochemical and physical forcing on hourly to inter-annual time scales, including those of land runoff. Our data demonstrate that coral reefs are subject to a wide range of pCO2, both on short and long time scales, and significant differences in the CO2-carbonic acid system dynamics across these various settings. We report that coral communities currently thrive in areas where the concentrations of CO2 can range from extremes as low as 200 ppm to as high as 1000 ppm and can fluctuate by ~500 ppm on any given day. The data provide evidence that net ecosystem calcification currently occurs in the presence of levels of CO2 predicted to occur well into the next century, although these coral reef ecosystems are only exposed to the extremes for short periods of time each day.
The use of handheld GPS to determine tidal slack in estuaries
NASA Astrophysics Data System (ADS)
Lievens, M.; Savenije, H.; Luxemburg, W.
2010-12-01
The phase lag between the moment of high water and high water slack, respectively low water and low water slack, is a key parameter in tidal hydraulics which is often disregarded. Savenije (1992) found that there are simple analytical relations for estuary topography, wave celerity and phase lag, that can be derived from the equation for conservation of mass and momentum. At present, methods to determine the phase lag by measuring the moment of tidal slack in the field are often either inadequate or very expensive. To be sure if assumptions made for the analytical derivation are acceptable, measuring the ‘real’ moment of tidal slack in the field is necessary. The method to determine the exact moment of tidal slack, developed in this work, is based on the use of a simple handheld GPS at some locations in the Dutch part of the Scheldt estuary. The GPS device is attached to a shipping lane buoy, which is fixed to the bottom of the estuary with a long chain. The chain gives the buoy enough space for an amplitude of approximately 25 - 30 meters. The GPS device measures the location of the buoy every 30 seconds for a few days. The data from the GPS results in a nice view of the path that the buoy travelled. The moment that the buoy switches direction, should be the moment of tidal slack. The “GPS method” of measuring the phase lag would allow application on full estuary scale in the future. Besides that, we get more insight in the key parameter of slack times for tidal hydraulics. The results are also of key importance to commercial shipping, towage and salvage companies and other users of estuaries worldwide.
Preliminary Assessment of Wind and Wave Retrieval from Chinese Gaofen-3 SAR Imagery
Sun, Jian
2017-01-01
The Chinese Gaofen-3 (GF-3) synthetic aperture radar (SAR) launched by the China Academy of Space Technology (CAST) has operated at C-band since September 2016. To date, we have collected 16/42 images in vertical-vertical (VV)/horizontal-horizontal (HH) polarization, covering the National Data Buoy Center (NDBC) buoy measurements of the National Oceanic and Atmospheric Administration (NOAA) around U.S. western coastal waters. Wind speeds from NDBC in situ buoys are up to 15 m/s and buoy-measured significant wave height (SWH) has ranged from 0.5 m to 3 m. In this study, winds were retrieved using the geophysical model function (GMF) together with the polarization ratio (PR) model and waves were retrieved using a new empirical algorithm based on SAR cutoff wavelength in satellite flight direction, herein called CSAR_WAVE. Validation against buoy measurements shows a 1.4/1.9 m/s root mean square error (RMSE) of wind speed and a 24/23% scatter index (SI) of SWH for VV/HH polarization. In addition, wind and wave retrieval results from 166 GF-3 images were compared with the European Centre for Medium-Range Weather Forecasts (ECMWF) re-analysis winds, as well as the SWH from the WaveWatch-III model, respectively. Comparisons show a 2.0 m/s RMSE for wind speed with a 36% SI of SWH for VV-polarization and a 2.2 m/s RMSE for wind speed with a 37% SI of SWH for HH-polarization. Our work gives a preliminary assessment of the wind and wave retrieval results from GF-3 SAR images for the first time and will provide guidance for marine applications of GF-3 SAR. PMID:28757571
NASA Technical Reports Server (NTRS)
Mcmillan, J. D.
1981-01-01
The accuracy of the GEOS-3 significant waveheight estimates compared with buoy measurements of significant waveheight were determined. A global atlas of the GEOS-3 significant waveheight estimates gathered is presented. The GEOS-3 significant waveheight estimation algorithm is derived by analyzing the return waveform characteristics of the altimeter. Convergence considerations are examined, the rationale for a smoothing technique is presented and the convergence characteristics of the smoothed estimate are discussed. The GEOS-3 data are selected for comparison with buoy measurements. The GEOS-3 significant waveheight estimates are assembled in the form of a global atlas of contour maps. Both high and low sea state contour maps are presented, and the data are displayed both by seasons and for the entire duration of the GEOS-3 mission.
Pilot Study Evaluating Nearshore Sediment Placement Sites, Noyo Harbor, CA
2013-02-01
distribution at the end of simulation (day 30). ............................. 33 Tables Table 1. NDBC, CDIP , and NOAA station locations...data are available from the National Data Buoy Center (NDBC, http://www.ndbc.noaa.gov) Buoy 46022 and Coastal Data Information Program ( CDIP , http...ft (1.8 m). Table 1 lists the NDBC, CDIP , and NOAA stations of interest and their location information. 2.4 Sediment characteristics A recent
33 CFR 110.179 - Skidaway River, Isle of Hope, Ga.
Code of Federal Regulations, 2014 CFR
2014-07-01
... anchorage ground. An area in Skidaway River beginning at a point on the mean low water line 400 feet south of Brady Boat Works, thence 76°30′, 300 feet to a buoy; thence 152°30′, 900 feet to a buoy; thence 251°00′, 450 feet to the mean low water line at Wymberly Yacht Club dock. (b) The regulations. (1...
33 CFR 110.179 - Skidaway River, Isle of Hope, Ga.
Code of Federal Regulations, 2011 CFR
2011-07-01
... anchorage ground. An area in Skidaway River beginning at a point on the mean low water line 400 feet south of Brady Boat Works, thence 76°30′, 300 feet to a buoy; thence 152°30′, 900 feet to a buoy; thence 251°00′, 450 feet to the mean low water line at Wymberly Yacht Club dock. (b) The regulations. (1...
33 CFR 110.179 - Skidaway River, Isle of Hope, Ga.
Code of Federal Regulations, 2012 CFR
2012-07-01
... anchorage ground. An area in Skidaway River beginning at a point on the mean low water line 400 feet south of Brady Boat Works, thence 76°30′, 300 feet to a buoy; thence 152°30′, 900 feet to a buoy; thence 251°00′, 450 feet to the mean low water line at Wymberly Yacht Club dock. (b) The regulations. (1...
33 CFR 110.179 - Skidaway River, Isle of Hope, Ga.
Code of Federal Regulations, 2013 CFR
2013-07-01
... anchorage ground. An area in Skidaway River beginning at a point on the mean low water line 400 feet south of Brady Boat Works, thence 76°30′, 300 feet to a buoy; thence 152°30′, 900 feet to a buoy; thence 251°00′, 450 feet to the mean low water line at Wymberly Yacht Club dock. (b) The regulations. (1...
Wave Evolution in River Mouths and Tidal Inlets
2014-06-01
Monterey Bay by a Datawell Buoy (blue) and three collocated WRD buoys (red). Also shown is the f −4 spectral roll off (black dashed). .............. 48...f −4 spectral roll off (black dashed) and the blocking frequency in regions B-E. .................................................... 53 Figure...Significant Wave Height Hz hertz IMU Inertial measurement unit JONSWAP Joint North Sea Wave Program km kilometer MCR Mouth of the Columbia River MEMS
An Integrated Network of In situ and Remote Sensors to Characterize the Somali Current
2015-09-30
streams for assimilation into numerical models • Introduce oceanography as an applied science to the Government of the Seychelles APPROACH...by U.S. Navy assets, indigenous Seychelles fishing vessels and by the Royal Australian Navy (RAN) during this period of performance. Figure (1...depicts a buoy deployment evolution in June 2015 and is representative of most deployments. Miniature wave buoy deployment dates: Seychelles
Development and testing of a novel subsea production system and control buoy
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1997-04-01
The remoteness of Australia`s northwest shelf presents challenges for the economic viability of offshore resource-development projects. Accordingly, the East Spar development has been designed to minimize capital and life-cycle costs to ensure the long-term viability of this offshore gas field. The offshore facilities are made up of a novel unmanned navigation, communication, and control (NCC) buoy linked to a subsea-production system that includes heat exchangers, insert-retrievable choke valves, multiphase flow-meters, and an on-line pipeline-corrosion monitoring system. The technological building blocks for field development are industry proved. However, the novel arrangement of this proven technology into a remotely controlled, self-contained, minimum-maintenancemore » unmanned facility is unique and has led to many challenges during the design and testing of the NCC buoy and subsea facilities. Among these challenges has been the formulation of an integration test program of the NCC buoy and subsea hardware that proves, as far as reasonably possible, the complete functionality of each equipment item and interface, subject to constraints imposed by schedule, cost, and logistics. Integration testing is particularly important to confirm that the offshore facilities will operate as designed with sufficient reliability and system redundancy to ensure continuous operation throughout the 20-year field life.« less
Response of Sea Ice and Marine Ecosystems to the Observed Warming Trends in the Arctic
NASA Technical Reports Server (NTRS)
Cota, Glenn F.; Comiso, Joey C.
2004-01-01
Our third (final) year activities have focused on two elements: 1) Creating and evaluating panarctic weekly climatologies of ocean color products for 1998 through 2002, 2) Interacting to assess image databases, submit and revise publications. Comiso and his programmer have principal responsibility for assembling and archiving the monthly and weekly image database at GSFC. There are now five year's (1998-2002) of climatologies. In addition to email correspondence, the PIs have met to prepare a series of publications ranging from panarctic physical-biological interactions to more focused regional studies.
Software defined multi-spectral imaging for Arctic sensor networks
NASA Astrophysics Data System (ADS)
Siewert, Sam; Angoth, Vivek; Krishnamurthy, Ramnarayan; Mani, Karthikeyan; Mock, Kenrick; Singh, Surjith B.; Srivistava, Saurav; Wagner, Chris; Claus, Ryan; Vis, Matthew Demi
2016-05-01
Availability of off-the-shelf infrared sensors combined with high definition visible cameras has made possible the construction of a Software Defined Multi-Spectral Imager (SDMSI) combining long-wave, near-infrared and visible imaging. The SDMSI requires a real-time embedded processor to fuse images and to create real-time depth maps for opportunistic uplink in sensor networks. Researchers at Embry Riddle Aeronautical University working with University of Alaska Anchorage at the Arctic Domain Awareness Center and the University of Colorado Boulder have built several versions of a low-cost drop-in-place SDMSI to test alternatives for power efficient image fusion. The SDMSI is intended for use in field applications including marine security, search and rescue operations and environmental surveys in the Arctic region. Based on Arctic marine sensor network mission goals, the team has designed the SDMSI to include features to rank images based on saliency and to provide on camera fusion and depth mapping. A major challenge has been the design of the camera computing system to operate within a 10 to 20 Watt power budget. This paper presents a power analysis of three options: 1) multi-core, 2) field programmable gate array with multi-core, and 3) graphics processing units with multi-core. For each test, power consumed for common fusion workloads has been measured at a range of frame rates and resolutions. Detailed analyses from our power efficiency comparison for workloads specific to stereo depth mapping and sensor fusion are summarized. Preliminary mission feasibility results from testing with off-the-shelf long-wave infrared and visible cameras in Alaska and Arizona are also summarized to demonstrate the value of the SDMSI for applications such as ice tracking, ocean color, soil moisture, animal and marine vessel detection and tracking. The goal is to select the most power efficient solution for the SDMSI for use on UAVs (Unoccupied Aerial Vehicles) and other drop-in-place installations in the Arctic. The prototype selected will be field tested in Alaska in the summer of 2016.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marelle, L.; Raut, Jean-Christophe; Thomas, J. L.
During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM 2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM 2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we findmore » that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM 10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM 2.5, modeled black carbon and SO 4 = concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m −2, peaking at +3.3 W m −2 at noon over Scandinavia and Finland.« less
Oil development and conservation in Arctic America
Reed, J.C.
1972-01-01
As in his earlier article to which reference is made, the author stresses the need for more background information and a much greater research effort before problems of environmental protection from oil developments in northern Alaska can be effectively tackled. Meanwhile, there are indications that the earlier estimates of around ten thousand million barrels should be raised-perhaps to about five times as much. There has moreover been a great increate also in the known and probable gas reserves in northern Canada-particularly in the Arctic Archipelago. In spite of planned automation, people will be needed for development-including Eskimos and Indians, whose interests will be widely protected under the Alaska Native Claims Settlement Act of December 1971. The International Biological Programme 'Tundra Biome' projects have accumulated much new information, including the results to be expected from disturbing the tundra seriously, and means of preventing or repairing damage to it. There is much interest in Alaska and Canada in protection of the northern environment, and in the former the US National Environmental Policy Act is already leading to stricter control of some developments. ?? 1972.
Scaling Observations of Surface Waves in the Beaufort Sea
2016-04-14
the treatment of wind input can be improved in partial ice cover using the ice concentration, where wave energy is a function of open water distance...drifting buoys during the 2014 open water season, are interpreted using open water distances determined from satellite ice products and wind forcing time...series measured in situ with the buoys. A significant portion of the wave observations were found to be limited by open water distance (fetch) when
Boussinesq Modeling of Wave Propagation and Runup over Fringing Coral Reefs, Model Evaluation Report
2007-12-01
60 Figure 58. Wave climate recorded by CDIP Sta 121 at Ipan in October 2005...buoy installed by the Coastal Data Information Program ( CDIP ) of Scripps Institution of Oceanography provided data on the incident wave conditions. The...buoy ( CDIP Sta 121) is located in 200 m of water at 13.3542°N, 144.7883°E, approximately 2.4 km southeast of the instrumentation transect. The
Enhancement of the United States Naval Academy (USNA) Polar Science Program (PSP)
2013-09-30
buoy hull design was designed, modeled , and tested. And initial analysis was performed on the NAICEX snow and ice data by midshipmen. RESULTS...to help better understand how the IABP buoys are performing (Fig. 4). The near real time webcam information has proved extremely beneficial for... IABP ). Mishipman Julia Zook works with University of Washington Engineer Jim Johnson on the IK3T during her summer internship to Barrow, AK
The Feasibility of Sodar Wind Profile Measurements from an Oceanographic Buoy
2006-09-01
Brown and Hwang ,1997; Graber et. al., 2000). Waves can be measured from the ASIS buoy using a six-element array of capacitance wave staffs...turbine wakes measured by sodar. Journal of Atmospheric and Oceanic Technology., 20, 466-477. Brown , Robert G. and Patrick Y.C. Hwang (1997...Introduction to random signals and applied Kalman filtering, 3rd ed., J. Wiley. Clay, Clarence S., Herman Medwin (1977): Acoustical Oceanography, J. Wiley
Automated calculation of surface energy fluxes with high-frequency lake buoy data
Woolway, R. Iestyn; Jones, Ian D; Hamilton, David P.; Maberly, Stephen C; Muroaka, Kohji; Read, Jordan S.; Smyth, Robyn L; Winslow, Luke A.
2015-01-01
Lake Heat Flux Analyzer is a program used for calculating the surface energy fluxes in lakes according to established literature methodologies. The program was developed in MATLAB for the rapid analysis of high-frequency data from instrumented lake buoys in support of the emerging field of aquatic sensor network science. To calculate the surface energy fluxes, the program requires a number of input variables, such as air and water temperature, relative humidity, wind speed, and short-wave radiation. Available outputs for Lake Heat Flux Analyzer include the surface fluxes of momentum, sensible heat and latent heat and their corresponding transfer coefficients, incoming and outgoing long-wave radiation. Lake Heat Flux Analyzer is open source and can be used to process data from multiple lakes rapidly. It provides a means of calculating the surface fluxes using a consistent method, thereby facilitating global comparisons of high-frequency data from lake buoys.
Evaluating Surface Radiation Fluxes Observed From Satellites in the Southeastern Pacific Ocean
NASA Astrophysics Data System (ADS)
Pinker, R. T.; Zhang, B.; Weller, R. A.; Chen, W.
2018-03-01
This study is focused on evaluation of current satellite and reanalysis estimates of surface radiative fluxes in a climatically important region. It uses unique observations from the STRATUS Ocean Reference Station buoy in a region of persistent marine stratus clouds 1,500 km off northern Chile during 2000-2012. The study shows that current satellite estimates are in better agreement with buoy observations than model outputs at a daily time scale and that satellite data depict well the observed annual cycle in both shortwave and longwave surface radiative fluxes. Also, buoy and satellite estimates do not show any significant trend over the period of overlap or any interannual variability. This verifies the stability and reliability of the satellite data and should make them useful to examine El Niño-Southern Oscillation variability influences on surface radiative fluxes at the STRATUS site for longer periods for which satellite record is available.
Benchmark Modeling of the Near-Field and Far-Field Wave Effects of Wave Energy Arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rhinefrank, Kenneth E; Haller, Merrick C; Ozkan-Haller, H Tuba
2013-01-26
This project is an industry-led partnership between Columbia Power Technologies and Oregon State University that will perform benchmark laboratory experiments and numerical modeling of the near-field and far-field impacts of wave scattering from an array of wave energy devices. These benchmark experimental observations will help to fill a gaping hole in our present knowledge of the near-field effects of multiple, floating wave energy converters and are a critical requirement for estimating the potential far-field environmental effects of wave energy arrays. The experiments will be performed at the Hinsdale Wave Research Laboratory (Oregon State University) and will utilize an array ofmore » newly developed Buoys' that are realistic, lab-scale floating power converters. The array of Buoys will be subjected to realistic, directional wave forcing (1:33 scale) that will approximate the expected conditions (waves and water depths) to be found off the Central Oregon Coast. Experimental observations will include comprehensive in-situ wave and current measurements as well as a suite of novel optical measurements. These new optical capabilities will include imaging of the 3D wave scattering using a binocular stereo camera system, as well as 3D device motion tracking using a newly acquired LED system. These observing systems will capture the 3D motion history of individual Buoys as well as resolve the 3D scattered wave field; thus resolving the constructive and destructive wave interference patterns produced by the array at high resolution. These data combined with the device motion tracking will provide necessary information for array design in order to balance array performance with the mitigation of far-field impacts. As a benchmark data set, these data will be an important resource for testing of models for wave/buoy interactions, buoy performance, and far-field effects on wave and current patterns due to the presence of arrays. Under the proposed project we will initiate high-resolution (fine scale, very near-field) fluid/structure interaction simulations of buoy motions, as well as array-scale, phase-resolving wave scattering simulations. These modeling efforts will utilize state-of-the-art research quality models, which have not yet been brought to bear on this complex problem of large array wave/structure interaction problem.« less
Towards marine seismological Network: real time small aperture seismic array
NASA Astrophysics Data System (ADS)
Ilinskiy, Dmitry
2017-04-01
Most powerful and dangerous seismic events are generated in underwater subduction zones. Existing seismological networks are based on land seismological stations. Increased demands for accuracy of location, magnitude, rupture process of coming earthquakes and at the same time reduction of data processing time require information from seabed seismic stations located near the earthquake generation area. Marine stations provide important contribution for clarification of the tectonic settings in most active subduction zones of the world. Early warning system for subduction zone area is based on marine seabed array which located near the area of most hazardous seismic zone in the region. Fast track processing for location of the earthquake hypocenter and energy takes place in buoy surface unit. Information about detected and located earthquake reaches the onshore seismological center earlier than the first break waves from the same earthquake will reach the nearest onshore seismological station. Implementation of small aperture array is based on existed and shown a good proven performance and costs effective solutions such as weather moored buoy and self-pop up autonomous seabed seismic nodes. Permanent seabed system for real-time operation has to be installed in deep sea waters far from the coast. Seabed array consists of several self-popup seismological stations which continuously acquire the data, detect the events of certain energy class and send detected event parameters to the surface buoy via acoustic link. Surface buoy unit determine the earthquake location by receiving the event parameters from seabed units and send such information in semi-real time to the onshore seismological center via narrow band satellite link. Upon the request from the cost the system could send wave form of events of certain energy class, bottom seismic station battery status and other environmental parameters. When the battery life of particular seabed unit is close to became empty, the seabed unit is switching into sleep mode and send that information to surface buoy and father to the onshore data center. Then seabed unit can wait for the vessel of opportunity for recovery of seabed unit to sea surface and replacing seabed station to another one with fresh batteries. All collected permanent seismic data by seabed unit could than downloaded for father processing and analysis. In our presentation we will demonstrate the several working prototypes of proposed system such as real time cable broad band seismological station and real time buoy seabed seismological station.
Research and Development of An In-situ Real-time Coastal Monitoring System
NASA Astrophysics Data System (ADS)
Deponte, D.; Cecco, R.; Laterza, R.; Medeot, N.; Nair, R.; Viezzoli, D.
The coastal area is a complex system in which the effects of the forcing terms on the circulation and mixing present a marked space-time variability on widely differing scales. In order to study such a system, it is necessary to monitor continuously, at high frequency, oceanographic and meteorological variables. To meet this need, the OGS has developed a coastal meteo-oceanographic buoy, called MAMBO, constituted by a float, a hull, a tripod and a powering system based on batteries recharged by so- lar panels that have been expressly designed and assembled by an in-house technical team. The buoy is equipped with a mechanical winch driving a multi-parametric pro- filing probe which provides data on pressure, temperature, salinity, dissolved oxygen, chlorophyll, pH and turbidity over the entire water column. Meteorological data (air temperature, barometric pressure and wind) are also measured. Data are acquired ev- ery 3 hours and transmitted via GSM cellular phone to a receiving station at the OGS in real-time where they are automatically subjected to a first level quality-check and made available to the public at the OGS web site. The buoy also serves as a convenient platform for a separate OGS-developed controller that manages an upward-looking ADCP-600kHz positioned on the sea floor close to the buoy. This controller regu- lates the ADCP power supply and permits the real-time transmission of pressure and current data to land via GSM cellular phone. Since there are no limitations due to bat- teries or memory capacity, currents can be sampled at high spatial and time resolution. Moreover, the controller permits to remotely change the configuration of the instru- ment in order to increase, for example, vertical resolution, and eventually, to record wave data. The first buoy of this type has been operating in the Gulf of Trieste (North Adriatic Sea) since 1998, and it is being continually improved. Two others, supplied additionally with a GPS, a radiometer and a hygrometer and improved with respect to some mechanical parts, have been deployed since June 2000, in the coastal area to the north of Sardinia (Tyrrhenian Sea). The development of an effective quality control procedure, that can be applied in real-time to the acquired data and that can permit the design of an efficient maintenance program for the buoy sensors, is in progress.
Indian Island Mooring Project. Phase II. Completion Report.
1984-03-01
32151 B 4299 31859 B 3327 31317 C 4460 31138 C 4266 31414 BUOY #2 394572 1532350 BUOY # 5 393784 1532410 ANCHOR A 4987 32457 ANCHOR A 4044 32990 B 4279...WASHINGTON, D. C. 20374 ;- -:r- -.. :;.\\:.,;:.:- ,- ---- :..-.- -.:-:::.:-:". 5 --.:.-..".- ".".--, .S .’---. : ..-. - ... V-.. .... :.. BLOCK 19 (Con’t...NUMBER 5 . MONITORING ORGANIZATION REPORT # FPO-1-84(2) 6a. NAME OF PERFORM. ORG. 6b. OFFICE SYM 7a. NAME OF MONITORING ORGANIZATION Robert Taggart
Summer 1983 Leeway Drift Experiment.
1985-08-01
used as the basis for the SAR Manual’s recommendation ( Scobie and Thompson, 1979). The RFD raft was deflected to the right or left of the wind...a leeway study for undrogued, canopied life rafts ( Scobie and Thompson, 1979). The current was measured by a buoy equipped with a 10-foot (3 m...recommendation for the canopied rafts with deep-draft ballast systems is based on data using a buoy with a 10-foot (3-m) square window-shade drogue ( Scobie
Assessment of the Water Levels and Currents at the Mississippi Bight During Hurricane Katrina.
NASA Astrophysics Data System (ADS)
Nwankwo, U. C.; Howden, S. D.; Dodd, D.; Wells, D. E.
2017-12-01
In an effort to extend the length of GPS baselines further offshore, the Hydrographic Science Research Center at the University of Southern Mississippi deployed a buoy which had a survey grade GPS receiver, an ADPC and a motion sensor unit in the Mississippi Bight in late 2004. The GPS data were initially processed using the Post Processed Kinematic technique with data from a nearby GPS base station on Horn Island. This processing technique discontinued when the storm (Hurricane Katrina) destroyed the base station in late August of 2005. However, since then a stand-alone positioning technique termed Precise Point Positioning (PPP) matured and allowed for the reprocessing of the buoy GPS data throughout Katrina. The processed GPS data were corrected for buoy angular motions using Tait Bryan transformation model. Tidal datums (Epoch 1983-2001) were transferred from the National Oceanic and Atmospheric Administration (NOAA) National Water Level at Waveland, Mississippi (Station ID 8747766) to the buoy using the Modified Range Ratio method. The maximum water level during the storm was found to be about 3.578m, relative to the transferred Mean Sea Level datum. The storm surge built over more than 24 hours, but fell back to normal levels in less than 3 hours. The maximum speed of the current with respect to the seafloor was recorded to be about 4knots towards the southeast as the storm surge moved back offshore.
Calibration of the TOPEX altimeter using a GPS buoy
NASA Technical Reports Server (NTRS)
Born, G. H.; Parke, Michael E.; Axelrad, P.; Gold, K. L.; Johnson, James; Key, K.; Kubitschek, Daniel G.; Christensen, Edward J.
1994-01-01
The use of a spar buoy equipped with a Global Positioning System (GPS) antenna to calibrate the height measurement of the TOPEX radar altimeter is described. In order to determine the height of the GPS antenna phase center above the ocean surface, the buoy was also equipped with instrumentation to measure the instantaneous location of the waterline, and tilt of the bouy from vertical. The experiment was conducted off the California coast near the Texaco offshore oil platform, Harvest, during cycle 34 of the TOPEX/POSEIDON observational period. GPS solutions were computed for the bouy position using two different software packages, K&RS and GIPSY-OASIS II. These solutions were combined with estimates of the waterline location on the bouy to yield the height of the ocean surface. The ocean surface height in an absolute coordinate system combined with knowledge of the spacecraft height from tracking data provides a computed altimeter range measurement. By comparing this computed value to the actual altimeter measurement, the altimeter bias can be calibrated. The altimeter height bias obtained with the buoy using K&RS was -14.6 +/- 4 cm, while with GIPSY-OASIS II it was -13.1 +/- 4 cm. These are 0.1 cm and 1.6 cm different from the -14.7 +/- 4 cm result obtained for this flight overflight with the tide gauge instruments located on Platform Harvest.
Drones for Provision of Flotation Support in Simulated Drowning.
Bäckman, Anders; Hollenberg, Jacob; Svensson, Leif; Ringh, Mattias; Nordberg, Per; Djärv, Therese; Forsberg, Sune; Hernborg, Olof; Claesson, Andreas
The feasibility and potential of using drones for providing flotation devices in cases of drowning have not yet been assessed. We hypothesize that a drone carrying an inflatable life buoy is a faster way to provide flotation compared with traditional methods. The purpose of this study is to explore the feasibility and efficiency of using a drone for delivering and providing flotation support to conscious simulated drowning victims. A simulation study was performed with a simulated drowning victim 100 m from the shore. A drone (DJI Phantom 4; dji, Shenzhen, China) equipped with an inflatable life buoy of 60 N was compared with traditional surf rescue swimming for providing flotation. The primary outcome was delay (minutes:seconds). A total number of 30 rescues were performed with a median time to delivery of the floating device of 30 seconds (interquartile range [IQR] = 24-32 seconds) for the drone compared with 65 seconds (IQR = 60-77 seconds) with traditional rescue swimming (P < .001). The drone had an accuracy of 100% in dropping the inflatable life buoy < 5 m from the victim, with a median of 1 m (IQR = 1-2 m). Using drones to deliver inflatable life buoys is safe and may be a faster method to provide early flotation devices to conscious drowning victims compared with rescue swimming. Copyright © 2018 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.
Continuous Wavelet Transform Analysis of Acceleration Signals Measured from a Wave Buoy
Chuang, Laurence Zsu-Hsin; Wu, Li-Chung; Wang, Jong-Hao
2013-01-01
Accelerometers, which can be installed inside a floating platform on the sea, are among the most commonly used sensors for operational ocean wave measurements. To examine the non-stationary features of ocean waves, this study was conducted to derive a wavelet spectrum of ocean waves and to synthesize sea surface elevations from vertical acceleration signals of a wave buoy through the continuous wavelet transform theory. The short-time wave features can be revealed by simultaneously examining the wavelet spectrum and the synthetic sea surface elevations. The in situ wave signals were applied to verify the practicality of the wavelet-based algorithm. We confirm that the spectral leakage and the noise at very-low-frequency bins influenced the accuracies of the estimated wavelet spectrum and the synthetic sea surface elevations. The appropriate thresholds of these two factors were explored. To study the short-time wave features from the wave records, the acceleration signals recorded from an accelerometer inside a discus wave buoy are analysed. The results from the wavelet spectrum show the evidence of short-time nonlinear wave events. Our study also reveals that more surface profiles with higher vertical asymmetry can be found from short-time nonlinear wave with stronger harmonic spectral peak. Finally, we conclude that the algorithms of continuous wavelet transform are practical for revealing the short-time wave features of the buoy acceleration signals. PMID:23966188
Advanced, High Power, Next Scale, Wave Energy Conversion Device
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mekhiche, Mike; Dufera, Hiz; Montagna, Deb
2012-10-29
The project conducted under DOE contract DE‐EE0002649 is defined as the Advanced, High Power, Next Scale, Wave Energy Converter. The overall project is split into a seven‐stage, gated development program. The work conducted under the DOE contract is OPT Stage Gate III work and a portion of Stage Gate IV work of the seven stage product development process. The project effort includes Full Concept Design & Prototype Assembly Testing building on our existing PowerBuoy technology to deliver a device with much increased power delivery. Scaling‐up from 150kW to 500kW power generating capacity required changes in the PowerBuoy design that addressedmore » cost reduction and mass manufacturing by implementing a Design for Manufacturing (DFM) approach. The design changes also focused on reducing PowerBuoy Installation, Operation and Maintenance (IO&M) costs which are essential to reducing the overall cost of energy. In this design, changes to the core PowerBuoy technology were implemented to increase capability and reduce both CAPEX and OPEX costs. OPT conceptually envisaged moving from a floating structure to a seabed structure. The design change from a floating structure to seabed structure would provide the implementation of stroke‐ unlimited Power Take‐Off (PTO) which has a potential to provide significant power delivery improvement and transform the wave energy industry if proven feasible.« less
Analysis of Surface Albedo to Improve Upper-Ocean Heat Budget Calculations
NASA Astrophysics Data System (ADS)
Hogikyan, A.; Zhang, D.; Cronin, M. F.
2016-12-01
Over 90% of the Earth's energy imbalance is stored in the oceans, so it is important to understand the ocean-atmosphere heat transfer. The Ocean Climate Stations group (OCS) at the Pacific Marine Environmental Laboratory maintains two moored surface buoys in the North Pacific (PAPA and KEO) as air-sea flux reference sites. The goal of the reference sites is to validate global air-sea flux products from atmospheric reanalyses and satellite products, that are critical to understand and model the variability and trend of the earth climate. As other air-sea flux reference buoys in the world ocean, PAPA and KEO only measure downward shortwave radiation (SWdown), but utilize the albedo and the directly measured SWdown to calculate the SWup. Since the open ocean albedo is small, the errors associated with this practice are thought to be comparable or smaller than the instrumentation errors in the air-sea flux measurements. In addition, it is generally accepted that ocean surface albedos can be derived with reasonable confidence from surface radiative fluxes in satellite products such as the Clouds and the Earth's Radiant Energy System (CERES) and the International Satellite Cloud Climatology Project (ISCCP). This project developed a CERES-based albedo product for derivation of SWnet at PAPA and KEO, and assessed the impact of CERES-based albedo on the net surface heat fluxes relative to the currently used ISCCP-based albedo in the OCS air-sea flux data (http://www.pmel.noaa.gov/ocs/data/fluxdisdel/). The high-resolution surface fluxes from CERES are more frequently updated, and consider more physical factors in the approximation, than those from ISCCP. There was a greater change between ISCCP and CERES albedo during wintertime than during summer. There was a greater change at Station PAPA in the northeastern sub-Arctic Pacific, than at Station KEO in the northwestern subtropical Pacific. The rate of temperature change of the mixed-layer is shown to increase based on the new source of albedo data, .08 and .5 °C/year at KEO and PAPA, respectively. The differences in the net surface heat flux due to different albedos used in this study suggest that more comprehensive investigations of the albedo in different products and radiative models, and their impacts on oceanic and atmospheric processes are needed.
Rip current monitoring using GPS buoy system
NASA Astrophysics Data System (ADS)
Song, DongSeob; Kim, InHo; Kang, DongSoo
2014-05-01
The occurrence of rip current in the Haeundae beach, which is one of the most famous beaches in South Korea, has been threatening beach-goers security in summer season annually. Many coastal scientists have been investigating rip currents by using field observations and measurements, laboratory measurements and wave tank experiments, and computer and numerical modeling. Rip current velocity is intermittent and may rapidly increase within minutes due to larger incoming wave groups or nearshore circulation instabilities. It is important to understand that changes in rip current velocity occur in response to changes in incoming wave height and period as well as changes in water level. GPS buoys have been used to acquire sea level change data, atmospheric parameters and other oceanic variables in sea for the purposes of vertical datum determination, tide correction, radar altimeter calibration, ocean environment and marine pollution monitoring. Therefore, we adopted GPS buoy system for an experiment which is to investigate rip current velocity; it is sporadic and may quickly upsurge within minutes due to larger arriving wave groups or nearshore flow uncertainties. In this study, for high accurate positioning of buy equipment, a Satellite Based Argumentation System DGPS data logger was deployed to investigate within floating object, and it can be acquired three-dimensional coordinate or geodetic position of buoy with continuous NMEA-0183 protocol during 24 hours. The wave height measured by in-situ hydrometer in a cross-shore array clearly increased before and after occurrence of rip current, and wave period also was lengthened around an event. These results show that wave height and period correlate reasonably well with long-shore current interaction in the Haeundae beach. Additionally, current meter data and GPS buoy data showed that rip current velocities, about 0.2 m/s, may become dangerously strong under specific conditions. Acknowledgement This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2010-0024670)
Wave and Current Measurements From the Coastal Storms Program (CSP) Buoy 41012 off St. Augustine, FL
NASA Astrophysics Data System (ADS)
Crout, R. L.
2008-05-01
The Coastal Storms Program (CSP) is a NOAA program that involves several different branches within NOAA. Components of the National Ocean Service, the National Weather Service, the National Marine Fisheries Service, and the Office of Oceanic and Atmospheric Research participate in CSP, which is administered by the Coastal Services Center. CSP selects an area where an impact in support of the NOAA Societal Goals can be made. The first area selected was the northeast coast of Florida in 2002. In addition to coastal water level stations and modeling efforts, a 3-meter discuss buoy (WMO 41012) was deployed off the coast of St. Augustine, FL in approximately 38 meters of water. In addition to the normal complement of meteorological sensors, Buoy 41012 contained a sensor to measure directional waves at hourly intervals, a temperature-conductivity sensor to measure near-surface temperature and salinity, and a current profiler to obtain near-surface to near-bottom currents at hourly intervals. These data on the continental shelf provide a view of the oceanography on the inner margin of the Gulf Stream. The data are served over the National Data Buoy Center's web page and over the Global Telecommunications System. The waves and currents during the period from September 2005 through December 2007 are related to coastal storms, hurricanes, tides, and Gulf Stream intrusions. During several late fall and winter periods the waves exceeded 4.5 meters. The on-offshore component of the currents appears to be tidally driven, however, predominant on- and off-shore flows are observed in response to storms and Gulf Stream intrusions. The primary component of the flow is aligned alongshore and although the tidal influence is obvious, extended periods of northward and southward currents are observed. Currents approaching 2 knots are observed at various times during the period that the buoy has been active. The high currents appear to be in response to strong wind events (atmospheric frontal passages) and Gulf Stream intrusions.
[Research, impact and adaptation in public health for the new climate of Quebec].
Gosselin, Pierre; Bélanger, Diane
2010-01-01
After its modest beginnings focusing on arctic Quebec in 1999, the Quebec research programme on health and climate change became interested in the remainder of the province around 2002. The European heat wave in 2003 accelerated the pace of this programme and prompted the Quebec health sector's participation in the Ouranos Research Consortium. The research findings from the 2003-2006 period have directly fed into the health component of the Quebec government's climate change action plan (2006-2012), financed through the first carbon tax in the Americas. This component is planning for a series of adaptations to the health network and to some other public networks, which will apply to construction, the built environment and outdoor developments, clinical management methods and practices, public health surveillance as well as emergency preparedness. In this article, the authors describe how research is supporting action and implementation, while also preparing for the future, and how this interaction has progressively established itself over the last 10 years.
NASA Astrophysics Data System (ADS)
Belchansky, G.; Eremeev, V.; Mordvintsev, I.; Platonov, N.; Douglas, D.
The melting events (early melt, melt onset, melt ponding, freeze-up onset) over Arctic sea-ice area are critical for climate and global change studies. They are combined with accuracy of surface energy balances estimates (due to contrasts in the short wave albedo of snow and ice, open water or melt ponds) and drives a number of important processes (onset of snow melt, thawing of boreal forest, etc). M icrowave measurements identify seasonal transition zones due to large differences in emissivity during melt onset, melt ponding and freeze-up periods. This report presents near coincident observation of backscatter cross section (0 ) and brightness temperature (Tb) from Russian OKEAN 01 satellite series, backscatter cross section (0) from RADARSAT-1, brightness temperatures (Tbs) from SSM/I sensors, and near-surface temperature derived from the International Arctic Buoy Program data (IABP) (Belchansky and Douglas, 2000, 2002). To determine the melt duration (time of freeze-up onset minus time of melt onset) passive and active microwave methods were developed. These methods used differences between SSM /I 19.3GHz,H and SSM/I 37.0 GHz, H channels (SSM/I Tb), OKEAN 0 (9.52GHz, VV) and Tb (37.47 GHz, H) channels, RADARSAT-1 0 (5.3GHz, HH), and a threshold technique. An evolution of the SSM/I Tb, OKEAN-01 0 and Tb, RADARSAT ScanSAR 0, MEAN ( 0), SD(0) and SD(0 ) / MEAN(0 ) as function of time was investigated along FY and MY dominant type ice areas during January 1996 through December 1998. The SSM/I, OKEAN and RADARSAT melt onset and freeze up onset algorithms were constructed. The SSM/I algorithm was based- on analysis of the SSM/I Tb. The OKEAN and RADARSAT ScanSAR algorithms were based, respectively, on analysis of OKEAN 0 and Tb of MY and FY sea ice at each MY and FY ice region (200 km by 200 km) determined in OKEAN imagery prior to melting period and changes in RADARSAT SD(0 ) / MEAN(0) of sea-ice during different stages of melting processes at each ice site (75 km by 75 km) determined prior to spring period in ScanSAR imagery. The averaged 12-h near surface temperatures derived from the IABP wer e used to analyze changes in the SSM/I Tb, OKEAN 0 and OKEAN Tb, RADARSAT SD(0) / MEAN(0), and to estimate respective thresholds associated with the melt onset and freeze-up onset. To highlight the sources of differences among various sensors results were compared to understand how the average the melt onset, melt duration and freeze-up onset estimates varied between different instruments and algorithms. A discrepancy in estimates resulted due to the nature of active and passive microwave measurements, frequency and polarization, number of channels, temperature and emissivity effects, and algorithm types. Higher spatial resolution of OKEAN-01 and RADARSAT-1 SAR was an important characteristic for obtaining better estimates of melting parameters. The SSM/ data provide a spatial resolution with global coverageI suitable for circulation models. Therefore OKEAN-01 and RADARSAT measurements can complement SSM/I data. These studies contribute to the growing body of documentation about the levels of disparity obtained when Arctic seasonal transition parameters are calculated using various types of satellite sensors and algorithms. ACKNOWLEDGEMENTS This work was carried out with the support from the International Arctic Research Center and Cooperative Institute for Arctic Research (IARC/CIFAR), University of Alaska Fairbanks. We would like to acknowledge the Alaska SAR Facility (Fairbanks), the National Snow and Ice Data Center (University of Colorado), and the Global Hydrology Resource Center, respectively, for providing RADARSAT images, the DMSP SSM/I Daily Polar Gridded Tb and Sea Ice Concentrations, the single-pass SSM/I brightness temperature data. REFERENCES Belchansky, G. I. and Douglas, D. C. (2000). Classification methods for monitoring Arctic sea-ice using OKEAN passive / active two-channel microwave data. J. Remote Sensing of Environment, Elsevier Science, New York. 73 (3): 307 -322. Belchansky, G. I. and Douglas, D. C. (2002). Seasonal comparisons of sea ice concentration estimates derived from SSM /I, OKEAN, and RADARSAT data. J. Remote Sensing of Environment, Elsevier Science, New York, 81 (1): 67-81.
Collective doses to man from dumping of radioactive waste in the Arctic Seas.
Nielsen, S P; Iosjpe, M; Strand, P
1997-08-25
A box model for the dispersion of radionuclides in the marine environment covering the Arctic Ocean and the North Atlantic Ocean has been constructed. Collective doses from ingestion pathways have been calculated from unit releases of the radionuclides 3H, 60Co, 63Ni, 90Sr, 129I, 137Cs, 239Pu and 241Am into a fjord on the east coast of NovayaZemlya. The results show that doses for the shorter-lived radionuclides (e.g. 137Cs) are derived mainly from seafood production in the Barents Sea. Doses from the longer-lived radionuclides (e.g. 239Pu) are delivered through marine produce further away from the Arctic Ocean. Collective doses were calculated for two release scenarios, both of which are based on information of the dumping of radioactive waste in the Barents and Kara Seas by the former Soviet Union and on preliminary information from the International Arctic Sea Assessment Programme. A worst-case scenario was assumed according to which all radionuclides in liquid and solid radioactive waste were available for dispersion in the marine environment at the time of dumping. Release of radionuclides from spent nuclear fuel was assumed to take place by direct corrosion of the fuel ignoring the barriers that prevent direct contact between the fuel and the seawater. The second scenario selected assumed that releases of radionuclides from spent nuclear fuel do not occur until after failure of the protective barriers. All other liquid and solid radioactive waste was assumed to be available for dispersion at the time of discharge in both scenarios. The estimated collective dose for the worst-case scenario was about 9 manSv and that for the second scenario was about 3 manSv. In both cases, 137Cs is the radionuclide predicted to dominate the collective doses as well as the peak collective dose rates.
Wave Field Characterization Using Dual-Polarized Pulse-Doppler X-Band Radar
2012-06-01
spectrum (frequencies higher than that associated with the wind wave peak) are similar for the buoy and Doppler, and likewise for the ultrasound array and...values of the RCS and ultrasound array relative to the buoy and Doppler are due to the formers’ larger energy levels at high frequencies. NSWCCD-50-TR...pp. 199- 203, 2008. [II] W. J. Plant, W. C. Keller, A. B. Reeves, E. A. Uliana, and J. W. Johnson, " Airborne microwave Doppler measurements of
Observations of Inertio-Gravity Waves in the Wake of Hurricane Frederic.
1983-12-01
Prederic passed within 80 to 130 km .4.1-4, 13 S4 W. W. of the array sites (Fig. 1) at 2100 GMT 12 September. Five hours later, Frederic made landfall... Prederic from a GOES satellite at 2001 GMT 12 September clearly delineates a well developed eye of about • % 140 tc 50 km in diameter (Figure 2). The...Renvick, 1981, Buoy observations during the passage of hurricane Prederic 1979, Data Report, NOA Data Buoy Cffice, NSTL Station, Hississippi. Kase, R. H
A SHALLOW WATER ISOBARIC BUOY.
The genesis, development, and testing of an instrument for following currents in shallow waters is described. The volume of the ’shallow water ...isobaric buoy’ (SWIB) varies in response to pressure signals derived from the depth of the water in which the instrument floats. Mechanisms for auto...indicate the feasibility of the system. The instrument can hover in a relatively restricted horizontal layer. The instrument may find application as a water stability indicator as well as a shallow water current tag. (Author)
2012-12-01
traditional buoy measurements , which are based on the analysis of the buoy motion using accelerometer and tilt sensors, is the capacity to detect multi-modal...the radar- based estimates slightly overestimate the measured data. Fig. 6.33 shows a time series of p-p-distances and corresponding water depths as...32 3.5 Time series of wind speed and direction measurements from ship anemome- ters 1 and 2 from
Utilization of space technology for terrestrial solar power applications
NASA Technical Reports Server (NTRS)
Yasui, R. K.; Patterson, R. E.
1974-01-01
A description is given of the evolution of photovoltaic power systems designed and built for terrestrial applications, giving attention to problem areas which are currently impeding the further development of such systems. The rooftop testing of surplus solar panels is considered along with solar powered seismic observatories, solar powered portable radio sets, and design considerations identified from past experience. Present activities discussed are related to a solar powered on-shore beacon flasher system, a solar powered buoy, and a solar powered beacon flasher buoy.
Sea King SHOL Support for Post-HCM/FELEX HALIFAX Class Ships
2014-05-01
correct this, a Network Time Protocol (NTP) time server was installed on two Raspberry - Pi computers3 (one used as a backup). Time was set to GPS time...data is needed, a wave buoy would be deployed for direct measurement. However, the launch & recovery of a 3The Raspberry Pi is an inexpensive credit...card-sized single-board computer developed in the UK by the Raspberry Pi Foundation. DRDC-RDDC-2014-R18 15 wave buoy was not practical in conjunction
WHOI Hawaii Ocean Timeseries Station (WHOTS): WHOTS-3 Mooring Turnaround Cruise Report
2007-05-01
ship then maneuvered slowly ahead to allow the buoy to come around to the stem. The winch operator slowly hauled in the slack wire, once the buoy had...Institution and Roger Lukas’ group at the University of Hawaii. The cruise took place between 22 and 29 June 2006. Operations on site were initiated...Griffiths, and a NOAA Hollings Scholar, Terry Smith, participated in the cruise. This report describes the mooring operations , some of the pre-cruise
Displacement of Tethered Hydro-Acoustic Modems by Uniform Horizontal Currents
2009-12-01
smooth and plane surfaces (in incompressible flow ) in air and in water (From [4]) ..............22 Figure 13. Drag of streamline bodies, tested in...from a stationary sea- surface buoy or Unmanned Surface Vehicle (USV) weighted by a dense object at the free end (Figure 2). The equations of static...forces on the free end are caused by an attached ballast or float. The moored cable has a free -moving sub- surface buoy positioned at a water depth
1982-10-01
this is critical. All buoy and many shore based systems employ back-up systems . In the case of buoys, 4 -when a lamp fails to emit, a new lamp is...88 LIST OF TABLES 1. Incandescent Source Table of Information -------------------- 38 2. Background Information on Subjects...functional aids-to-navigation system . The principal component of this system is the lighted aid which exists in many forms, from the wind and wave
Comparison Between Sea Surface Wind Speed Estimates From Reflected GPS Signals and Buoy Measurements
NASA Technical Reports Server (NTRS)
Garrison, James L.; Katzberg, Steven J.; Zavorotny, Valery U.
2000-01-01
Reflected signals from the Global Positioning System (GPS) have been collected from an aircraft at approximately 3.7 km altitude on 5 different days. Estimation of surface wind speed by matching the shape of the reflected signal correlation function against analytical models was demonstrated. Wind speed obtained from this method agreed with that recorded from buoys to with a bias of less than 0.1 m/s, and with a standard derivation of 1.3 meters per second.
50 CFR 648.10 - VMS and DAS requirements for vessel owners/operators.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN... Little River Light 44°39.0′ 67°10.5′ 4. Whistle Buoy “8BI” (SSE of Baker Island) 44°13.6′ 68°10.8′ 5... Neddick Light 43°09.9′ 70°34.5′ 10. Merrimack River Entrance “MR” Whistle Buoy 42°48.6′ 70°47.1′ 11...
Sea Ice Surface Temperature Product from the Moderate Resolution Imaging Spectroradiometer (MODIS)
NASA Technical Reports Server (NTRS)
Hall, Dorothy K.; Key, Jeffrey R.; Casey, Kimberly A.; Riggs, George A.; Cavalieri, Donald J.
2003-01-01
Global sea ice products are produced from the Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) on board both the Terra and Aqua satellites. Daily sea ice extent and ice-surface temperature (IST) products are available at 1- and 4-km resolution. Validation activities have been undertaken to assess the accuracy of the MODIS IST product at the South Pole station in Antarctica and in the Arctic Ocean using near-surface air-temperature data from a meteorological station and drifting buoys. Results from the study areas show that under clear skies, the MODIS ISTs are very close to those of the near-surface air temperatures with a bias of -1.1 and -1.2 K, and an uncertainty of 1.6 and 1.7 K, respectively. It is shown that the uncertainties would be reduced if the actual temperature of the ice surface were reported instead of the near-surface air temperature. It is not possible to get an accurate IST from MODIS in the presence of even very thin clouds or fog, however using both the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and the MODIS on the Aqua satellite, it may be possible to develop a relationship between MODIS-derived IST and ice temperature derived from the AMSR-E. Since the AMSR-E measurements are generally unaffected by cloud cover, they may be used to complement the MODIS IST measurements.
NASA Astrophysics Data System (ADS)
Trembanis, A. C.; Levin, D.; Seidel, J.
2012-12-01
The Chester River has been the subject of ongoing scientific studies in response to both the Clean Water Act and the EPA's Chesapeake Bay Program initiatives. The Upper, Middle, and Lower Chester are on the Maryland Department of Environment's list of "impaired waters". The Chester River Watershed (CRW) Observatory is lead by the Center for Environment & Society at Washington College. Eight clusters representing 22 public and private K-12 schools in the CRW provide the sampling sites distributed throughout the watershed. Weather stations will be installed at these sites allowing monitoring of the watershed's microclimate. Each cluster will be assigned a Basic Observation Buoy (BOB), an easy to assemble inexpensive buoy platform for real-time water column and atmospheric condition measurements. The BOBs are fitted with a data sonde to collect similar data parameters (e.g. salinity, temperature) as the main stem Chesapeake Bay buoys do. These assets will be deployed and the data transmitted to the Chester River Geographic Information System site for archival and visual display. Curriculum already developed for the Chesapeake Bay Interpretive Buoy System by the NOAA Chesapeake Bay Office will be adapted to the Chester River Watershed. Social issues of water sustainability will be introduced using the Watershed Game (Northland NEMO ®). During 2011 NOAA's Chesapeake Bay Office completed curriculum projects including Chesapeake Exploration, Build-a-Buoy (BaBs) and Basic Observation Buoys (BOBs). These engaging projects utilize authentic data and hands-on activities to demonstrate the tools scientists use to understand system interactions in the Bay. Chesapeake Exploration is a collection of online activities that provides teachers and students with unprecedented access to Bay data. Students are guided through a series of tasks that explore topics related to the interrelation between watersheds, land-use, weather, water quality, and living resources. The BaBs and BOBs (developed by Levin) engage students in the building and testing of buoys to monitor the environment. Additional hands on science activities include the Levin developed ROVs-in-a-bucket project that Trembanis has incorporated into the University of Delaware high school summer science camp TIDE (Teaching an Interest in Delaware's Estuary) http://www.ceoe.udel.edu/tide/ in which 12-15 high school students annually participate in groups working to design, build, and operate a simple remotely operated vehicle in a series of real work simulation activities such as responding to an oil spill. The new CRW network will be the focus for formal and informal learning partnerships between schools in the watershed. Professional development opportunities for Chester River watershed teachers focus on the use of sensors, utilization of GIS in the classroom, and other resources that become available as shared teaching resources. Federal, state, regional, and local users in government, private industry, and educational venues from grades k-16 will be able to observe the trends and learn together the most prudent ways to sustain and conserve natural resources.
NASA Astrophysics Data System (ADS)
Hong, Sinpyo; Lee, Inwon; Park, Seong Hyeon; Lee, Cheolmin; Chun, Ho-Hwan; Lim, Hee Chang
2015-09-01
An experimental study of the effect of mooring systems on the dynamics of a SPAR buoy-type floating offshore wind turbine is presented. The effects of the Center of Gravity (COG), mooring line spring constant, and fair-lead location on the turbine's motion in response to regular waves are investigated. Experimental results show that for a typical mooring system of a SPAR buoy-type Floating Offshore Wind Turbine (FOWT), the effect of mooring systems on the dynamics of the turbine can be considered negligible. However, the pitch decreases notably as the COG increases. The COG and spring constant of the mooring line have a negligible effect on the fairlead displacement. Numerical simulation and sensitivity analysis show that the wind turbine motion and its sensitivity to changes in the mooring system and COG are very large near resonant frequencies. The test results can be used to validate numerical simulation tools for FOWTs.
He, Pingguo; Suuronen, Petri
2018-04-01
Fishing gears are marked to establish and inform origin, ownership and position. More recently, fishing gears are marked to aid in capacity control, reduce marine litter due to abandoned, lost or otherwise discarded fishing gear (ALDFG) and assist in its recovery, and to combat illegal, unreported and unregulated (IUU) fishing. Traditionally, physical marking, inscription, writing, color, shape, and tags have been used for ownership and capacity purposes. Buoys, lights, flags, and radar reflectors are used for marking of position. More recently, electronic devices have been installed on marker buoys to enable easier relocation of the gear by owner vessels. This paper reviews gear marking technologies with focus on coded wire tags, radio frequency identification tags, Automatic Identification Systems, advanced electronic buoys for pelagic longlines and fish aggregating devices, and re-location technology if the gear becomes lost. Copyright © 2018 Elsevier Ltd. All rights reserved.
Reedsport PB150 Deployment and Ocean Test Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hart, Phil
2016-06-03
As the first utility scale wave power project in the US, the Wave Power Demonstration Project at Reedsport (OR) was planned to consist of 10 PowerBuoys (Phase II)1, located 2.5 miles off the coast. U.S. Department of Energy (DOE) funding under a prior DOE Grant (DE-FG36-08GO88017) along with funding from PNGC Power, an Oregon-based electric power cooperative, was utilized for the design completion, fabrication, assembly and factory testing of the first PowerBuoy for the Reedsport project. The design and fabrication of the first PowerBuoy and factory testing of the power take-off subsystem were completed, and the power take-off subsystem wasmore » successfully integrated into the spar at the fabricator’s facility in Oregon. The objectives of this follow-on grant were: advance PB150B design from TRL 5/6 to TRL 7/8; deploy a single PB150 and operate autonomously for 2 years; establish O&M costs; collect environmental information; and establish manufacturing methodologies.« less
Fall Freeze-up of Sea Ice in the Beaufort-Chukchi Seas Using ERS-1 SAR and Buoy Data
NASA Technical Reports Server (NTRS)
Holt, B.; Winebrenner, B.; D., Nelson E.
1993-01-01
The lowering of air temperatures below freezing in the fall indicates the end of summer melt and the onset of steady sea ice growth. The thickness and condition of ice that remains at the end of summer has ramifications for the thickness that that ice will attain at the end of the following winter. This period also designates a shifting of key fluxes from upper ocean freshening from ice melt to increased salinity from brine extraction during ice growth. This transitional period has been examined in the Beaufort and Chukchi Seas using ERS-1 SAR imagery and air temperatures from drifting buoys during 1991 and 1992. The SAR imagery is used to examine the condition and types of ice present in this period. Much of the surface melt water has drained off at this time. Air temperatures from drifting buoys coincident in time and within 100 km radius of the SAR imagery have been obtained...
Rollover of Apparent Wave Attenuation in Ice Covered Seas
NASA Astrophysics Data System (ADS)
Li, Jingkai; Kohout, Alison L.; Doble, Martin J.; Wadhams, Peter; Guan, Changlong; Shen, Hayley H.
2017-11-01
Wave attenuation from two field experiments in the ice-covered Southern Ocean is examined. Instead of monotonically increasing with shorter waves, the measured apparent attenuation rate peaks at an intermediate wave period. This "rollover" phenomenon has been postulated as the result of wind input and nonlinear energy transfer between wave frequencies. Using WAVEWATCH III®, we first validate the model results with available buoy data, then use the model data to analyze the apparent wave attenuation. With the choice of source parameterizations used in this study, it is shown that rollover of the apparent attenuation exists when wind input and nonlinear transfer are present, independent of the different wave attenuation models used. The period of rollover increases with increasing distance between buoys. Furthermore, the apparent attenuation for shorter waves drops with increasing separation between buoys or increasing wind input. These phenomena are direct consequences of the wind input and nonlinear energy transfer, which offset the damping caused by the intervening ice.
The ODAS Italia 1 buoy: More than forty years of activity in the Ligurian Sea
NASA Astrophysics Data System (ADS)
Canepa, Elisa; Pensieri, Sara; Bozzano, Roberto; Faimali, Marco; Traverso, Pierluigi; Cavaleri, Luigi
2015-06-01
The Ligurian Sea plays a relevant role in driving both the circulation of the Western Mediterranean Sea and the weather and climate of the area. In order to better understand the peculiarities of this basin, the Oceanographic Data Acquisition System (ODAS) Italia 1 buoy was developed and deployed in the early '70s. Throughout the years, the buoy has been fitted with updated measuring and data acquiring systems. Since 2003 the buoy has been part of the Mediterranean Moored Multi-sensor Array network of fixed open ocean observatories with the W1-M3A identifier and presently constitutes one of the Mediterranean sites of the European FixO3 network. Recently, a deep-ocean sub-surface mooring line was, and is, deployed close to it in relation to specific projects. This multidisciplinary observing system is able to perform both long-term operational and ad-hoc monitoring from the lower atmosphere to the deep ocean. It is used for analysis of air-sea interaction processes, study of the physical proprieties of the water column, bio-geo-chemical monitoring of the sea, meteorological and oceanographic model evaluation, calibration of remotely sensed measurements, and development of innovative marine monitoring technologies. After reporting some historical notes and the description of the observing system, this paper summarises and reviews the main oceanographic and atmospheric studies performed during the last 15 years using the data acquired on board.
NASA Astrophysics Data System (ADS)
Rabatel, Matthias; Rampal, Pierre; Carrassi, Alberto; Bertino, Laurent; Jones, Christopher K. R. T.
2018-03-01
We present a sensitivity analysis and discuss the probabilistic forecast capabilities of the novel sea ice model neXtSIM used in hindcast mode. The study pertains to the response of the model to the uncertainty on winds using probabilistic forecasts of ice trajectories. neXtSIM is a continuous Lagrangian numerical model that uses an elasto-brittle rheology to simulate the ice response to external forces. The sensitivity analysis is based on a Monte Carlo sampling of 12 members. The response of the model to the uncertainties is evaluated in terms of simulated ice drift distances from their initial positions, and from the mean position of the ensemble, over the mid-term forecast horizon of 10 days. The simulated ice drift is decomposed into advective and diffusive parts that are characterised separately both spatially and temporally and compared to what is obtained with a free-drift model, that is, when the ice rheology does not play any role in the modelled physics of the ice. The seasonal variability of the model sensitivity is presented and shows the role of the ice compactness and rheology in the ice drift response at both local and regional scales in the Arctic. Indeed, the ice drift simulated by neXtSIM in summer is close to the one obtained with the free-drift model, while the more compact and solid ice pack shows a significantly different mechanical and drift behaviour in winter. For the winter period analysed in this study, we also show that, in contrast to the free-drift model, neXtSIM reproduces the sea ice Lagrangian diffusion regimes as found from observed trajectories. The forecast capability of neXtSIM is also evaluated using a large set of real buoy's trajectories and compared to the capability of the free-drift model. We found that neXtSIM performs significantly better in simulating sea ice drift, both in terms of forecast error and as a tool to assist search and rescue operations, although the sources of uncertainties assumed for the present experiment are not sufficient for complete coverage of the observed IABP positions.
Invited review: climate change impacts in polar regions: lessons from Antarctic moss bank archives.
Royles, Jessica; Griffiths, Howard
2015-03-01
Mosses are the dominant plants in polar and boreal regions, areas which are experiencing rapid impacts of regional warming. Long-term monitoring programmes provide some records of the rate of recent climate change, but moss peat banks contain an unrivalled temporal record of past climate change on terrestrial plant Antarctic systems. We summarise the current understanding of climatic proxies and determinants of moss growth for contrasting continental and maritime Antarctic regions, as informed by 13C and 18O signals in organic material. Rates of moss accumulation are more than three times higher in the maritime Antarctic than continental Antarctica with growing season length being a critical determinant of growth rate, and high carbon isotope discrimination values reflecting optimal hydration conditions. Correlation plots of 13C and 18O values show that species (Chorisodontium aciphyllum / Polytrichum strictum) and growth form (hummock / bank) are the major determinants of measured isotope ratios. The interplay between moss growth form, photosynthetic physiology, water status and isotope composition are compared with developments of secondary proxies, such as chlorophyll fluorescence. These approaches provide a framework to consider the potential impact of climate change on terrestrial Antarctic habitats as well as having implications for future studies of temperate, boreal and Arctic peatlands. There are many urgent ecological and environmental problems in the Arctic related to mosses in a changing climate, but the geographical ranges of species and life-forms are difficult to track individually. Our goal was to translate what we have learned from the more simple systems in Antarctica, for application to Arctic habitats. © 2014 John Wiley & Sons Ltd.
Production of Arctic Sea-ice Albedo by fusion of MISR and MODIS data
NASA Astrophysics Data System (ADS)
Kharbouche, Said; Muller, Jan-Peter
2017-04-01
We have combined data from the NASA MISR and MODIS spectro-radiometers to create a cloud-free albedo dataset specifically for sea-ice. The MISR (Multi-Angular Spectro-Radiometer) instrument on board Terra satellite has a unique ability to create high-quality Bidirectional Reflectance (BRF) over a 7 minute time interval per single overpass, thanks to its 9 cameras of different view angles (±70°,±60°,±45°,±26°). However, as MISR is limited to narrow spectral bands (443nm, 555nm, 670nm, 865nm), which is not sufficient to mask cloud effectively and robustly, we have used the sea-ice mask MOD09 product (Collection 6) from MODIS (Moderate resolution Imaging Spectoradiometer) instrument, which is also on board Terra satellite and acquiring data simultaneously. Only We have created a new and consistent sea-ice (for Arctic) albedo product that is daily, from 1st March to 22nd September for each and every year between 2000 to 2016 at two spatial grids, 1km x 1km and 5km x 5km in polar stereographic projection. Their analysis is described in a separate report [1]. References [1] Muller & Kharbouche, Variation of Arctic's Sea-ice Albedo between 2000 and 2016 by fusion of MISR and MODIS data. This conference. Acknowledgements This work was supported by www.QA4ECV.eu, a project of European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 607405. We thank our colleagues at JPL and NASA LaRC for processing these data, especially Sebastian Val and Steve Protack.
NASA Astrophysics Data System (ADS)
Fernandes, Maria; Alonso-Martirena, Andrés; Agostinho, Pedro; Sanchez, Jorge; Ferrer, Macu; Fernandes, Carlos
2015-04-01
The coastal zone is an important area for the development of maritime countries, either in terms of recreation, energy exploitation, weather forecasting or national security. Field measurements are in the basis of understanding how coastal and oceanic processes occur. Most processes occur over long timescales and over large spatial ranges, like the variation of mean sea level. These processes also involve a variety of factors such as waves, winds, tides, storm surges, currents, etc., that cause huge interference on such phenomena. Measurement of waves have been carried out using different techniques. The instruments used to measure wave parameters can be very different, i.e. buoys, ship base equipment like sonar and satellites. Each equipment has its own advantage and disadvantage depending on the study subject. The purpose of this study is to evaluate the behaviour of a different technology available and presently adopted in wave measurement. In the past few years the measurement of waves using High Frequency (HF) Radars has had several developments. Such a method is already established as a powerful tool for measuring the pattern of surface current, but its use in wave measurements, especially in the dual arrangement is recent. Measurement of the backscatter of HF radar wave provides the raw dataset which is analyzed to give directional data of surface elevation at each range cell. Buoys and radars have advantages, disadvantages and its accuracy is discussed in this presentation. A major advantage with HF radar systems is that they are unaffected by weather, clouds or changing ocean conditions. The HF radar system is a very useful tool for the measurement of waves over a wide area with real-time observation, but it still lacks a method to check its accuracy. The primary goal of this study was to show how the HF radar system responds to high energetic variations when compared to wave buoy data. The bulk wave parameters used (significant wave height, period and direction) were obtained during 2013 and 2014 from one 13.5 MHz CODAR SeaSonde radar station from Hydrographic Institute, located in Espichel Cape (Portugal). These data were compared with those obtained from one wave buoy Datawell Directional Waverider, also from Hydrographic Institute, moored inbound Sines (Portugal) at 100 m depth. For this first approach, was assumed that all the waves are in a deep water situation. Results showed that during high energetic periods, the HF radar system revealed a good correlation with wave buoy data following the bulk wave parameters gradient variations.
Accuracy in GPS/Acoustic positioning on a moored buoy moving around far from the optimal position
NASA Astrophysics Data System (ADS)
Imano, M.; Kido, M.; Ohta, Y.; Takahashi, N.; Fukuda, T.; Ochi, H.; Hino, R.
2015-12-01
For detecting the seafloor crustal deformation and Tsunami associated with large earthquakes in real-time, it is necessary to monitor them just above the possible source region. For this purpose, we have been dedicated in developing a real-time continuous observation system using a multi-purpose moored buoy. Sea-trials of the system have been carried out near the Nanakai trough in 2013 and 2014 (Takahashi et al., 2014). We especially focused on the GPS/Acoustic measurement (GPS/A) in the system for horizontal crustal movement. The GPS/A on a moored buoy has a critical drawback compared to the traditional ones, in which the data can be stacked over ranging points fixed at an optimal position. Accuracy in positioning with a single ranging from an arbitrary point is the subject to be improved in this study. Here, we report the positioning results in the buoy system using data in the 2014 sea-trial and demonstrate the improvement of the result. We also address the potential resolving power in the positioning using synthetic tests. The target GPS/A site consists of six seafloor transponders (PXPs) forming a small inner- and a large outer-triangles. The bottom of the moored cable is anchored nearly the center of the triangles. In the sea-trial, 11 times successive ranging was scheduled once a week, and we plotted positioning results from different buoy position. We confirmed that scatter in positioning using six PXPs simultaneously is ten times smaller than that using individual triangle separately. Next, we modified the definition of the PXP array geometry using data obtained in a campaign observation. Definition of an array geometry is insensitive as far as ranging is made in the same position, however, severely affects the positioning when ranging is made from various positions like the moored buoy. The modified PXP array is slightly smaller and 2m deeper than the original one. We found that the scatter of positioning results in the sea-trial is reduced from 4m to 1.7m with the modified geometry. Finally we produced a synthetic data with an artificial error in the array geometry and evaluated its effect on the positioning as a function of ranging point. This is interpreted with potential resolving power formulated in Kido (2007). In the presentation, we will show the results of synthetic test for systematic variation of the error condition.
Telemetry and control system for interplatform crude loading at the Statfjord Field
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malmin, P.C.; Lassa, P.
1986-01-01
A control system for crude loading to tankers at the Statfjord field has been designed by Mobil Exploration Norway Inc. The objective of the interplatform crude tieline and control system was to allow tanker loading to take place at all times in order to prevent production shutdowns due to loading buoy problems. The control system has been designed to maximize the flexibility of loading operations and meet all safety and regulatory requirements. This paper discusses the design criteria for the crude tieline control system, and describes how these were met by utilizing fail safe telemetry equipment, hardwired permissive relay logicmore » and programmable logic controllers (PLC's). The experience gained from more than three years of operation of the system is reviewed. The system has allowed maximum use of total field storage capacity while loading crude to 125000 DWT tankers nearly every day throughout the year. It has been possible to maintain a high production rate event through periods of difficult weather conditions as experienced in the northern North Sea.« less
Pre-exposure prophylaxis and antiretroviral resistance: HIV prevention at a cost?
Hurt, Christopher B; Eron, Joseph J; Cohen, Myron S
2011-12-01
Pre-exposure prophylaxis (PrEP), the use of antiretrovirals (ARVs) by human immunodeficiency virus (HIV)-uninfected individuals to prevent acquisition of the virus during high-risk sexual encounters, enjoyed its first 2 major successes with the Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 and the Pre-Exposure Prophylaxis Initiative (iPrEx). These successes were buoyed by additional positive results from the TDF2 and Partners PrEP trials. Although no seroconverters in either arm of CAPRISA developed resistance to tenofovir, 2 participants in iPrEx with undetected, seronegative acute HIV infection were randomized to receive daily oral tenofovir-emtricitabine and resistance to emtricitabine was later discovered in both men. A similar case in the TDF2 study resulted in resistance to both ARVs. These cases prompted us to examine existing literature on the nature of resistance mutations elicited by ARVs used for PrEP. Here, we discuss the impact of signature mutations selected by PrEP, how rapidly these emerge with daily ARV exposure, and the individual-level and public health consequences of ARV resistance.
NASA Astrophysics Data System (ADS)
Stroeve, J. C.
2014-12-01
The last four decades have seen a remarkable decline in the spatial extent of the Arctic sea ice cover, presenting both challenges and opportunities to Arctic residents, government agencies and industry. After the record low extent in September 2007 effort has increased to improve seasonal, decadal-scale and longer-term predictions of the sea ice cover. Coupled global climate models (GCMs) consistently project that if greenhouse gas concentrations continue to rise, the eventual outcome will be a complete loss of the multiyear ice cover. However, confidence in these projections depends o HoHoweon the models ability to reproduce features of the present-day climate. Comparison between models participating in the World Climate Research Programme Coupled Model Intercomparison Project Phase 5 (CMIP5) and observations of sea ice extent and thickness show that (1) historical trends from 85% of the model ensemble members remain smaller than observed, and (2) spatial patterns of sea ice thickness are poorly represented in most models. Part of the explanation lies with a failure of models to represent details of the mean atmospheric circulation pattern that governs the transport and spatial distribution of sea ice. These results raise concerns regarding the ability of CMIP5 models to realistically represent the processes driving the decline of Arctic sea ice and to project the timing of when a seasonally ice-free Arctic may be realized. On shorter time-scales, seasonal sea ice prediction has been challenged to predict the sea ice extent from Arctic conditions a few months to a year in advance. Efforts such as the Sea Ice Outlook (SIO) project, originally organized through the Study of Environmental Change (SEARCH) and now managed by the Sea Ice Prediction Network project (SIPN) synthesize predictions of the September sea ice extent based on a variety of approaches, including heuristic, statistical and dynamical modeling. Analysis of SIO contributions reveals that when the September sea ice extent is near the long-term trend, contributions tend to be accurate. Years when the observed extent departs from the trend have proven harder to predict. Predictability skill does not appear to be more accurate for dynamical models over statistical ones, nor is there a measurable improvement in skill as the summer progresses.
Tropical Pacific Observing for the Next Decade
NASA Astrophysics Data System (ADS)
Legler, David M.; Hill, Katherine
2014-06-01
More than 60 scientists and program officials from 13 countries met at the Scripps Institution of Oceanography for the Tropical Pacific Observing System (TPOS) 2020 Workshop. The workshop, although motivated in part by the dramatic decline of NOAA's Tropical Atmosphere Ocean (TAO) buoy reporting from mid-2012 to early 2014 (see http://www.bloomberg.com/news/2014-03-07/aging-el-nino-buoys-getting-fixed-as-weather-forecasts-at-risk.html), evaluated the needs for tropical Pacific observing and initiated efforts to develop a more resilient and integrative observing system for the future.
Time-Series Measurements of Atmospheric and Oceanic CO2 and O2 in the Western Gulf of Maine
2008-09-01
is 2 meters in diameter and 3.5 m tall with a Surlyn foam flotation collar (Gilman Corporation). The Surlyn foam was cut with two chines so that...the flotation in the lightweight foam, the buoy with full 978-1-4244-2620-1/08/$25.00 ©2008 IEEE Report Documentation Page Form ApprovedOMB No. 0704...deployments, necessitating routine servicing (buoy pulled on deck in good weather and cleaned) (Figure 8). Modifications to a 90/10 copper -nickel
1977-06-01
SPHEROIDAL BUOYS As mentioned previously, for the limiting case of zero ; educed frequency where tile free surface behaves as a rigid plane, the...4P ) -4 -4 ft O D - % Cdd :# P) fy ou Cd 1d Cd’. . 6 - C3 ’o .. eg S w Cd *g.4C~dI~**II~.a Ký 0 4 : 10 In H-C IV ..4 _ C) bu 0 40 la W C2C W cc lp lqa
Directional wave navigation radar measurements compared with pitch-roll buoy data
DOE Office of Scientific and Technical Information (OSTI.GOV)
A.-Munoyerro, M.A.; Borge, J.C.N.
1997-02-01
The knowledge of the spectral behavior of a specific sea region is complete when one knows surface elevations and directional wave movements. Usually, sea directional descriptions have been made using pitch-roll buoys, which can provide one with several wave characteristic time series. Alternatively, there are other measure systems, which belong to remote sensing technics, such as shipboard navigation radars. The aim of the present work is to compare results obtained from pitch-roll data and ship radar wave measurements obtained during a campaign in the Cantabric Sea.
1994-08-01
n.m.) (11 -km) grid of the Pacific Ocean between latitude 20ON to 60WN and longi- tude 1 10*W to 200*W using the WIS deepwater numerical model DWAVE ...represents a wave travelling towards the north). Comparisons with the DWAVE wind and wave results (Tracy and Payne 1990) were made with NOAA buoy...hindcast using the WIS numerical model DWAVE to the deepwater depth corresponding to the location of the NOAA buoy. Directional spectral infor- mation was
NASA Astrophysics Data System (ADS)
Lavin, Alicia; Somavilla, Raquel; Cano, Daniel; Rodriguez, Carmen; Gonzalez-Pola, Cesar; Viloria, Amaia; Tel, Elena; Ruiz-Villareal, Manuel
2017-04-01
Long-Term Time Series Stations have been developed in order to document seasonal to decadal scale variations in key physical and biogeochemical parameters. Long-term time series measurements are crucial for determining the physical and biological mechanisms controlling the system. The Science and Technology Ministers of the G7 in their Tsukuba Communiqué have stated that 'many parts of the ocean interior are not sufficiently observed' and that 'it is crucial to develop far stronger scientific knowledge necessary to assess the ongoing changes in the ocean and their impact on economies.' Time series has been classically obtained by oceanographic ships that regularly cover standard sections and stations. From 1991, shelf and slope waters of the Southern Bay of Biscay are regularly sampled in a monthly hydrographic line north of Santander to a depth of 1000 m in early stages and for the whole water column down to 2580 m in recent times. Nearby, in June 2007, the IEO deployed an oceanic-meteorological buoy (AGL Buoy, 43° 50.67'N; 3° 46.20'W, and 40 km offshore, www.boya-agl.st.ieo.es). The Santander Atlantic Time Series Station is integrated in the Spanish Institute of Oceanography Observing Sistem (IEOOS). The long-term hydrographic monitoring has allowed to define the seasonality of the main oceanographic facts as the upwelling, the Iberian Poleward Current, low salinity incursions, trends and interannual variability at mixing layer, and at the main water masses North Atlantic Central Water and Mediterranean Water. The relation of these changes with the high frequency surface conditions recorded by the Biscay AGL has been examined using also satellite and reanalysis data. During the FIXO3 Project (Fixed-point Open Ocean Observatories), and using this combined sources, some products and quality controled series of high interest and utility for scientific purposes has been developed. Hourly products as Sea Surface Temperature and Salinity anomalies, wave significant height character with respect to monthly average, and currents with respect to seasonal averages. Ocean-atmosphere heat fluxes (latent and sensible) are computed from the buoy atmospheric and oceanic measurements. Estimations of the mixed layer depth and bulk series at different water levels are provided in a monthly basis. Quality controlled series are distributed for sea surface salinity, oxygen and chlorophyll data. Some sensors are particularly affected by biofouling, and monthly visits to the buoy permit to follow these sensors behaviour. Chlorophyll-fluorescence sensor is the main concern, but Dissolved Oxygen sensor is also problematic. Periods of realistic smooth variations present strong offset that is corrected based on the Winkler analysis of water samples. Also Wind air temperature and humidilty buoy sensors are monthly compared with the research vessel data. Next step will consist in working on a better validation of the data, mainly ten-year data from the Biscay AGL buoy, but also the 25 year data of the station 7, close to the buoy. Data will be depurated an analyzed and the final product will be published and widening to improve and get the better use of them.