Doppler Sonar Current Indicator
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Turning the Tide on Trash: Great Lakes
Turning the Tide On Trash A LEARNING GUIDE ON MARINE DEBRIS Turning the Tide On Trash A LEARNING GUIDE ON MARINE DEBRIS Floating marine debris in Hawaii NOAA PIFSC CRED Educators, parents, students, and Unfortunately, the ocean is currently researchers can use Turning the Tide under considerable pressure. The on Trash as they explore the serious seeming vastness of the ocean has impacts that marine debris can have on prompted people to overestimate its wildlife, the environment, our well being, ability to safely absorb our wastes. For and our economy. too long, we have used these waters as a receptacle for our trash and other Covering nearly three-quarters of the wastes. Integrating the following lessons Earth, the ocean is an extraordinary and background chapters into your resource. The ocean supports fishing curriculum can help to teach students industries and coastal economies, that they can be an important part of the provides recreational opportunities, solution. Many of the lessons can also and serves as a nurturing home for a be modified for science fair projects and multitude of marine plants and wildlife. other learning extensions. C ON T EN T S 1 Acknowledgments & History of Turning the Tide on Trash 2 For Educators and Parents: How to Use This Learning Guide UNIT ONE 5 The Definition, Characteristics, and Sources of Marine Debris 17 Lesson One: Coming to Terms with Marine Debris 20 Lesson Two: Trash Traits 23 Lesson Three: A Degrading Experience 30 Lesson Four: Marine Debris – Data Mining 34 Lesson Five: Waste Inventory 38 Lesson -
Winds, Waves, and Bubbles at the Air-Sea Boundary
JEFFREY L. HANSON WINDS, WAVES, AND BUBBLES AT THE AIR-SEA BOUNDARY Subsurface bubbles are now recognized as a dominant acoustic scattering and reverberation mechanism in the upper ocean. A better understanding of the complex mechanisms responsible for subsurface bubbles should lead to an improved prediction capability for underwater sonar. The Applied Physics Laboratory recently conducted a unique experiment to investigate which air-sea descriptors are most important for subsurface bubbles and acoustic scatter. Initial analyses indicate that wind-history variables provide better predictors of subsurface bubble-cloud development than do wave-breaking estimates. The results suggest that a close coupling exists between the wind field and the upper-ocean mixing processes, such as Langmuir circulation, that distribute and organize the bubble populations. INTRODUCTION A multiyear series of experiments, conducted under the that, in the Gulf of Alaska wintertime environment, the auspices of the Navy-sponsored acoustic program, Crit amount of wave-breaking activity may not be an ideal ical Sea Test (CST), I has been under way since 1986 with indicator of deep bubble-cloud formation. Instead, the the charter to investigate environmental, scientific, and penetration of bubbles is more closely tied to short-term technical issues related to the performance of low-fre wind fluctuations, suggesting a close coupling between quency (100-1000 Hz) active acoustics. One key aspect the wind field and upper-ocean mixing processes that of CST is the investigation of acoustic backscatter and distribute and organize the bubble populations within the reverberation from upper-ocean features such as surface mixed layer. waves and bubble clouds. -
Wetsuits Raises the Bar Once Again, in Both Design and Technological Advances
Orca evokes the instinct and prowess of the powerful ruler of the seas. Like the Orca whale, our designs have always been organic, streamlined and in tune with nature. Our latest 2016 collection of wetsuits raises the bar once again, in both design and technological advances. With never before seen 0.88Free technology used on the Alpha, and the ultimate swim assistance WETSUITS provided by the Predator, to a more gender specific 3.8 to suit male and female needs, down to the latest evolution of the ever popular S-series entry-level wetsuit, Orca once again has something to suit every triathlete’s needs when it comes to the swim. 10 11 TRIATHLON Orca know triathletes and we’ve been helping them to conquer the WETSUITS seven seas now for more than twenty years.Our latest collection of wetsuits reflects this legacy of knowledge and offers something for RANGE every level and style of swimmer. Whether you’re a good swimmer looking for ultimate flexibility, a struggling swimmer who needs all the buoyancy they can get, or a weekend warrior just starting out, Orca has you covered. OPENWATER Swimming in the openwater is something that has always drawn those types of swimmers that find that the largest pool is too small for them. However open water swimming is not without it’s own challenges and Orca’s Openwater collection is designed to offer visibility, and so security, to those who want to take on this sport. 016 SWIMRUN The SwimRun endurance race is a growing sport and the wetsuit requirements for these competitors are unique. -
A Numerical Study of the Long- and Short-Term Temperature Variability and Thermal Circulation in the North Sea
JANUARY 2003 LUYTEN ET AL. 37 A Numerical Study of the Long- and Short-Term Temperature Variability and Thermal Circulation in the North Sea PATRICK J. LUYTEN Management Unit of the Mathematical Models, Brussels, Belgium JOHN E. JONES AND ROGER PROCTOR Proudman Oceanographic Laboratory, Bidston, United Kingdom (Manuscript received 3 January 2001, in ®nal form 4 April 2002) ABSTRACT A three-dimensional numerical study is presented of the seasonal, semimonthly, and tidal-inertial cycles of temperature and density-driven circulation within the North Sea. The simulations are conducted using realistic forcing data and are compared with the 1989 data of the North Sea Project. Sensitivity experiments are performed to test the physical and numerical impact of the heat ¯ux parameterizations, turbulence scheme, and advective transport. Parameterizations of the surface ¯uxes with the Monin±Obukhov similarity theory provide a relaxation mechanism and can partially explain the previously obtained overestimate of the depth mean temperatures in summer. Temperature strati®cation and thermocline depth are reasonably predicted using a variant of the Mellor±Yamada turbulence closure with limiting conditions for turbulence variables. The results question the common view to adopt a tuned background scheme for internal wave mixing. Two mechanisms are discussed that describe the feedback of the turbulence scheme on the surface forcing and the baroclinic circulation, generated at the tidal mixing fronts. First, an increased vertical mixing increases the depth mean temperature in summer through the surface heat ¯ux, with a restoring mechanism acting during autumn. Second, the magnitude and horizontal shear of the density ¯ow are reduced in response to a higher mixing rate. -
Prioritization of Oxygen Delivery During Elevated Metabolic States
Respiratory Physiology & Neurobiology 144 (2004) 215–224 Eat and run: prioritization of oxygen delivery during elevated metabolic states James W. Hicks∗, Albert F. Bennett Department of Ecology and Evolutionary Biology, University of California, Irvine, CA 92697, USA Accepted 25 May 2004 Abstract The principal function of the cardiopulmonary system is the matching of oxygen and carbon dioxide transport to the metabolic V˙ requirements of different tissues. Increased oxygen demands ( O2 ), for example during physical activity, result in a rapid compensatory increase in cardiac output and redistribution of blood flow to the appropriate skeletal muscles. These cardiovascular changes are matched by suitable ventilatory increments. This matching of cardiopulmonary performance and metabolism during activity has been demonstrated in a number of different taxa, and is universal among vertebrates. In some animals, large V˙ increments in aerobic metabolism may also be associated with physiological states other than activity. In particular, O2 may increase following feeding due to the energy requiring processes associated with prey handling, digestion and ensuing protein V˙ V˙ synthesis. This large increase in O2 is termed “specific dynamic action” (SDA). In reptiles, the increase in O2 during SDA may be 3–40-fold above resting values, peaking 24–36 h following ingestion, and remaining elevated for up to 7 days. In addition to the increased metabolic demands, digestion is associated with secretion of H+ into the stomach, resulting in a large metabolic − alkalosis (alkaline tide) and a near doubling in plasma [HCO3 ]. During digestion then, the cardiopulmonary system must meet the simultaneous challenges of an elevated oxygen demand and a pronounced metabolic alkalosis. -
Arenicola Marina During Low Tide
MARINE ECOLOGY PROGRESS SERIES Published June 15 Mar Ecol Prog Ser Sulfide stress and tolerance in the lugworm Arenicola marina during low tide Susanne Volkel, Kerstin Hauschild, Manfred K. Grieshaber Institut fiir Zoologie, Lehrstuhl fur Tierphysiologie, Heinrich-Heine-Universitat, Universitatsstr. 1, D-40225 Dusseldorf, Germany ABSTRACT: In the present study environmental sulfide concentrations in the vicinity of and within burrows of the lugworm Arenicola marina during tidal exposure are presented. Sulfide concentrations in the pore water of the sediment ranged from 0.4 to 252 pM. During 4 h of tidal exposure no significant changes of pore water sulfide concentrations were observed. Up to 32 pM sulfide were measured in the water of lugworm burrows. During 4 h of low tide the percentage of burrows containing sulfide increased from 20 to 50% in July and from 36 to 77% in October A significant increase of median sulfide concentrations from 0 to 14.5 pM was observed after 5 h of emersion. Sulfide and thiosulfate concentrations in the coelomic fluid and succinate, alanopine and strombine levels in the body wall musculature of freshly caught A. marina were measured. During 4 h of tidal exposure in July the percentage of lugworms containing sulfide and maximal sulfide concentrations increased from 17 % and 5.4 pM to 62% and 150 pM, respectively. A significant increase of median sulfide concentrations was observed after 2 and 3 h of emersion. In October, changes of sulfide concentrations were less pronounced. Median thiosulfate concentrations were 18 to 32 FM in July and 7 to 12 ~.IMin October No significant changes were observed during tidal exposure. -
POLÍTICA DE DIVERSIDADE E INCLUSÃO Sumário
POLÍTICA DE DIVERSIDADE E INCLUSÃO Sumário 5 Diversidade para combater as desigualdades 9 O Comitê de Diversidade e Inclusão 11 Entendendo um pouco sobre preconceito, discriminação, opressão estrutural, diversidade e inclusão 23 Quais temas serão tratados na Política de Diversidade e Inclusão da Fundação Tide Setubal? 39 Fundação Tide Setubal: princípios e compromissos 49 Canais de acolhimento 51 Referências Dezembro, 2020 Diversidade para combater as 1 desigualdades A Fundação Tide Setubal tem como missão “fomentar iniciativas que promovam a justiça social e o desenvol- vimento sustentável de periferias urbanas e contribuam para o enfrentamento das desigualdades socioespaciais das grandes cidades, em articulação com diversos agen- tes da sociedade civil, de instituições de pesquisa, do Estado e do mercado”. O uso do termo desigualdades, no plural, implica reconhecer que a vida dos sujeitos é atravessada não apenas pelas diferenças econômicas, mas também por uma série de fatores estruturais carac- terísticos de nossa sociedade que impactam a capacida- de das pessoas de viver e exercer seus direitos de forma plena. A discriminação e o preconceito sofridos por gru- pos minorizados também são vetores de exclusão social e contribuem para a reprodução e o aprofundamento do abismo social que separa incluídos e excluídos no Brasil. POLÍTICA DE DIVERSIDADE E INCLUSÃO 6 É com base nesse compromisso de combater as de- sigualdades em todas as suas formas que a Fundação apresenta esta Política de Diversidade e Inclusão. Nela, ficam estabelecidas as regras e compromissos que de- vem pautar a atuação de nossas colaboradoras e cola- boradores no sentido de combater ativamente todas as formas de discriminação e preconceito e promover a inclusão de todas as pessoas, independentemente de raça, gênero, orientação sexual, identidade de gênero, capacidade e origem nacional ou territorial. -
Subsurface Dinoflagellate Populations, Frontal Blooms and the Formation of Red Tide in the Southern Benguela Upwelling System
MARINE ECOLOGY PROGRESS SERIES Vol. 172: 253-264. 1998 Published October 22 Mar Ecol Prog Ser Subsurface dinoflagellate populations, frontal blooms and the formation of red tide in the southern Benguela upwelling system G. C. Pitcher*,A. J. Boyd, D. A. Horstman, B. A. Mitchell-Innes Sea Fisheries Research Institute, Private Bag X2, Rogge Bay 8012, Cape Town. South Africa ABSTRACT- The West Coast of South Africa is often subjected to problems associated with red tides which are usually attributed to blooms of migratory dinoflagellates. This study investigates the cou- pling between the physical environment and the biological behaviour and physiological adaptation of dinoflagellates in an attempt to understand bloom development, maintenance and decline. Widespread and persistent subsurface dinoflagellate populations domlnate the stratified waters of the southern Benguela during the latter part of the upwelling season. Chlorophyll concentrations as high as 50 mg m-3 are associated with the the]-mocline at approximately 20 m depth but photosynthesis in this region is restricted by low light. The subsurface population is brought to the surface in the region of the upwelling front. Here increased light levels are responsible for enhanced production, in some instances exceeding 80 mgC rn.' h ', and resulting in dense dinoflagellate concentrations in and around the uplifted thermocline. Under particular wind and current conditions these frontal bloon~sare trans- ported and accumulated inshore and red tides are formed. KEY WORDS: Dinoflagellates Subsurface populations . Frontal bloolns Red tide - Upwelling systems INTRODUCTION Pitcher 1996), or from physical damage, such as the clogging of fish gills (Grindley & Nel 1968, Brown et al. -
Fusion System Components
A Step Change in Military Autonomous Technology Introduction Commercial vs Military AUV operations Typical Military Operation (Man-Portable Class) Fusion System Components User Interface (HMI) Modes of Operation Typical Commercial vs Military AUV (UUV) operations (generalisation) Military Commercial • Intelligence gathering, area survey, reconnaissance, battlespace preparation • Long distance eg pipeline routes, pipeline surveys • Mine countermeasures (MCM), ASW, threat / UXO location and identification • Large areas eg seabed surveys / bathy • Less data, desire for in-mission target recognition and mission adjustment • Large amount of data collected for post-mission analysis • Desire for “hover” ability but often use COTS AUV or adaptations for specific • Predominantly torpedo shaped, require motion to manoeuvre tasks, including hull inspection, payload deployment, sacrificial vehicle • Errors or delays cost money • Errors or delays increase risk • Typical categories: man-portable, lightweight, heavy weight & large vehicle Image courtesy of Subsea Engineering Associates Typical Current Military Operation (Man-Portable Class) Assets Equipment Cost • Survey areas of interest using AUV & identify targets of interest: AUV & Operating Team USD 250k to USD millions • Deploy ROV to perform detailed survey of identified targets: ROV & Operating Team USD 200k to USD 450k • Deploy divers to deal with targets: Dive Team with Nav Aids & USD 25k – USD 100ks Diver Propulsion --------------------------------------------------------------------------------- -
Low-Frequency Active Towed Sonar
LOW-FREQUENCY ACTIVE TOWED SONAR Full-feature, long-range, low-frequency active and passive variable depth sonar (VDS) The Low-Frequency Active Sonar (LFATS) system is used on ships to detect, track and engage all types of submarines. L3Harris specifically designed the system to perform at a lower operating frequency against modern diesel-electric submarine threats. FEATURES > Compact size - LFATS is a small, > Full 360° coverage - a dual parallel array lightweight, air-transportable, ruggedized configuration and advanced signal system processing achieve instantaneous, > Specifically designed for easy unambiguous left/right target installation on small vessels. discrimination. > Configurable - LFATS can operate in a > Space-saving transmitter tow-body stand-alone configuration or be easily configuration - innovative technology integrated into the ship’s combat system. achieves omnidirectional, large aperture acoustic performance in a compact, > Tactical bistatic and multistatic capability sleek tow-body assembly. - a robust infrastructure permits interoperability with the HELRAS > Reverberation suppression - the unique helicopter dipping sonar and all key transmitter design enables forward, aft, sonobuoys. port and starboard directional LFATS has been successfully deployed on transmission. This capability diverts ships as small as 100 tons. > Highly maneuverable - own-ship noise energy concentration away from reduction processing algorithms, coupled shorelines and landmasses, minimizing with compact twin-line receivers, enable reverb and optimizing target detection. short-scope towing for efficient maneuvering, fast deployment and > Sonar performance prediction - a unencumbered operation in shallow key ingredient to mission planning, water. LFATS computes and displays system detection capability based on modeled > Compact Winch and Handling System or measured environmental data. - an ultrastable structure assures safe, reliable operation in heavy seas and permits manual or console-controlled deployment, retrieval and depth- keeping. -
Hydrographic Surveys Specifications and Deliverables
HYDROGRAPHIC SURVEYS SPECIFICATIONS AND DELIVERABLES March 2019 U.S. Department of Commerce National Oceanic and Atmospheric Administration National Ocean Service Contents 1 Introduction ......................................................................................................................................1 1.1 Change Management ............................................................................................................................................. 2 1.2 Changes from April 2018 ...................................................................................................................................... 2 1.3 Definitions ............................................................................................................................................................... 4 1.3.1 Hydrographer ................................................................................................................................................. 4 1.3.2 Navigable Area Survey .................................................................................................................................. 4 1.4 Pre-Survey Assessment ......................................................................................................................................... 5 1.5 Environmental Compliance .................................................................................................................................. 5 1.6 Dangers to Navigation .......................................................................................................................................... -
Sonar for Environmental Monitoring of Marine Renewable Energy Technologies
Sonar for environmental monitoring of marine renewable energy technologies FRANCISCO GEMO ALBINO FRANCISCO UURIE 350-16L ISSN 0349-8352 Division of Electricity Department of Engineering Sciences Licentiate Thesis Uppsala, 2016 Abstract Human exploration of the world oceans is ever increasing as conventional in- dustries grow and new industries emerge. A new emerging and fast-growing industry is the marine renewable energy. The last decades have been charac- terized by an accentuated development rate of technologies that can convert the energy contained in stream flows, waves, wind and tides. This growth ben- efits from the fact that society has become notably aware of the well-being of the environment we all live in. This brings a human desire to implement tech- nologies which cope better with the natural environment. Yet, this environ- mental awareness may also pose difficulties in approving new renewable en- ergy projects such as offshore wind, wave and tidal energy farms. Lessons that have been learned is that lack of consistent environmental data can become an impasse when consenting permits for testing and deployments marine renew- able energy technologies. An example is the European Union in which a ma- jority of the member states requires rigorous environmental monitoring pro- grams to be in place when marine renewable energy technologies are commis- sioned and decommissioned. To satisfy such high demands and to simultane- ously boost the marine renewable sector, long-term environmental monitoring framework that gathers multi-variable data are needed to keep providing data to technology developers, operators as well as to the general public. Technol- ogies based on active acoustics might be the most advanced tools to monitor the subsea environment around marine manmade structures especially in murky and deep waters where divining and conventional technologies are both costly and risky.