Wind, Wave and Current Interactions Appear Key for Quantifying Cross-Shelf Transport and Carbon
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Intracratonic Asthenosphere Upwelling and Lithosphere Rejuvenation
Earth and Planetary Science Letters 260 (2007) 482–494 www.elsevier.com/locate/epsl Intracratonic asthenosphere upwelling and lithosphere rejuvenation beneath the Hoggar swell (Algeria): Evidence from HIMU metasomatised lherzolite mantle xenoliths ⁎ L. Beccaluva a, , A. Azzouni-Sekkal b, A. Benhallou c, G. Bianchini a, R.M. Ellam d, M. Marzola a, F. Siena a, F.M. Stuart d a Dipartimento di Scienze della Terra, Università di Ferrara, Italy b Faculté des Sciences de la Terre, Géographie et Aménagement du Territoire, Université des Sciences et Technologie Houari Boumédienne, Alger, Algeria c CRAAG (Centre de Recherche en Astronomie, Astrophysique et Géophysique), Alger, Algeria d Isotope Geoscience Unit, Scottish Universities Environmental Research Centre, East Kilbride, UK Received 7 March 2007; received in revised form 23 May 2007; accepted 24 May 2007 Available online 2 June 2007 Editor: R.W. Carlson Abstract The mantle xenoliths included in Quaternary alkaline volcanics from the Manzaz-district (Central Hoggar) are proto-granular, anhydrous spinel lherzolites. Major and trace element analyses on bulk rocks and constituent mineral phases show that the primary compositions are widely overprinted by metasomatic processes. Trace element modelling of the metasomatised clinopyroxenes allows the inference that the metasomatic agents that enriched the lithospheric mantle were highly alkaline carbonate-rich melts such as nephelinites/melilitites (or as extreme silico-carbonatites). These metasomatic agents were characterized by a clear HIMU Sr–Nd–Pb isotopic signature, whereas there is no evidence of EM1 components recorded by the Hoggar Oligocene tholeiitic basalts. This can be interpreted as being due to replacement of the older cratonic lithospheric mantle, from which tholeiites generated, by asthenospheric upwelling dominated by the presence of an HIMU signature. -
Global Ship Accidents and Ocean Swell-Related Sea States
Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2017-142, 2017 Manuscript under review for journal Nat. Hazards Earth Syst. Sci. Discussion started: 26 April 2017 c Author(s) 2017. CC-BY 3.0 License. Global ship accidents and ocean swell-related sea states Zhiwei Zhang1, 2, Xiao-Ming Li2, 3 1 College of Geography and Environment, Shandong Normal University, Jinan, China 2 Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, 5 Beijing, China 3 Hainan Key Laboratory of Earth Observation, Sanya, China Correspondence to: X.-M. Li (E-mail: [email protected]) Abstract. With the increased frequency of shipping activities, navigation safety has become a major concern, especially when economic losses, human casualties and environmental issues are considered. As a contributing factor, sea state conditions play 10 a significant role in shipping safety. However, the types of dangerous sea states that trigger serious shipping accidents are not well understood. To address this issue, we analyzed the sea state characteristics during ship accidents that occurred in poor weather or heavy seas based on a ten-year ship accident dataset. The sea state parameters, including the significant wave height, the mean wave period and the mean wave direction, obtained from numerical wave model data were analyzed for selected ship accidents. The results indicated that complex sea states with the co-occurrence of wind sea and swell conditions represent 15 threats to sailing vessels, especially when these conditions include close wave periods and oblique wave directions. 1 Introduction The shipping industry delivers 90% of all world trade (IMO, 2011). -
Lesson 8: Currents
Standards Addressed National Science Lesson 8: Currents Education Standards, Grades 9-12 Unifying concepts and Overview processes Physical science Lesson 8 presents the mechanisms that drive surface and deep ocean currents. The process of global ocean Ocean Literacy circulation is presented, emphasizing the importance of Principles this process for climate regulation. In the activity, students The Earth has one big play a game focused on the primary surface current names ocean with many and locations. features Lesson Objectives DCPS, High School Earth Science Students will: ES.4.8. Explain special 1. Define currents and thermohaline circulation properties of water (e.g., high specific and latent heats) and the influence of large bodies 2. Explain what factors drive deep ocean and surface of water and the water cycle currents on heat transport and therefore weather and 3. Identify the primary ocean currents climate ES.1.4. Recognize the use and limitations of models and Lesson Contents theories as scientific representations of reality ES.6.8 Explain the dynamics 1. Teaching Lesson 8 of oceanic currents, including a. Introduction upwelling, density, and deep b. Lecture Notes water currents, the local c. Additional Resources Labrador Current and the Gulf Stream, and their relationship to global 2. Extra Activity Questions circulation within the marine environment and climate 3. Student Handout 4. Mock Bowl Quiz 1 | P a g e Teaching Lesson 8 Lesson 8 Lesson Outline1 I. Introduction Ask students to describe how they think ocean currents work. They might define ocean currents or discuss the drivers of currents (wind and density gradients). Then, ask them to list all the reasons they can think of that currents might be important to humans and organisms that live in the ocean. -
NWS Melbourne Marine Web Letter August 2013 (For Marine Forecast Questions 24/7: Call 321-255-0212, Ext
NWS Melbourne Marine Web Letter August 2013 (For Marine Forecast Questions 24/7: call 321-255-0212, ext. 2) Marine Links relevant to East Central Florida Buoy 41010 It is hoped that this buoy, which went adrift in February, will be redeployed by mid to late September. Additional Marine Observations I’ve added a web page that has most of the marine observations along the east coast. http://www.srh.noaa.gov/mlb/?n=marob Note that wind/wave data became available at Sebastian Inlet via the National Data Buoy Center earlier this year. There are also some web cams with wind data. One, at Jensen Beach, has wave data too. Upwelling Some on again, off again upwelling occurred over the continental shelf this summer. This is not unusual. South to southeast winds (near shore parallel) are the primary cause of periodic upwelling. In some years, these winds are persistent and stronger than normal, which produces more prolific upwelling. In 2003, water temps in the upper 50s occurred in mid August at Daytona Beach! Typically the upwelling diminishes by late August or September. Nearshore Wave Prediction System We will soon upgrade our nearshore wave model (SWAN) to the Nearshore Wave Prediction System (NWPS). One enhancement is that Gulf Stream data will be incorporated back into the wave model. This will allow us to give better estimates for the position of the west wall of the Gulf Stream. The wave model will again be able to generate higher wave heights in the Gulf Stream during northerly wind surges. Hopefully, this functionality will be ready by Fall when cold fronts start moving through again. -
Waves and Weather
Waves and Weather 1. Where do waves come from? 2. What storms produce good surfing waves? 3. Where do these storms frequently form? 4. Where are the good areas for receiving swells? Where do waves come from? ==> Wind! Any two fluids (with different density) moving at different speeds can produce waves. In our case, air is one fluid and the water is the other. • Start with perfectly glassy conditions (no waves) and no wind. • As wind starts, will first get very small capillary waves (ripples). • Once ripples form, now wind can push against the surface and waves can grow faster. Within Wave Source Region: - all wavelengths and heights mixed together - looks like washing machine ("Victory at Sea") But this is what we want our surfing waves to look like: How do we get from this To this ???? DISPERSION !! In deep water, wave speed (celerity) c= gT/2π Long period waves travel faster. Short period waves travel slower Waves begin to separate as they move away from generation area ===> This is Dispersion How Big Will the Waves Get? Height and Period of waves depends primarily on: - Wind speed - Duration (how long the wind blows over the waves) - Fetch (distance that wind blows over the waves) "SMB" Tables How Big Will the Waves Get? Assume Duration = 24 hours Fetch Length = 500 miles Significant Significant Wind Speed Wave Height Wave Period 10 mph 2 ft 3.5 sec 20 mph 6 ft 5.5 sec 30 mph 12 ft 7.5 sec 40 mph 19 ft 10.0 sec 50 mph 27 ft 11.5 sec 60 mph 35 ft 13.0 sec Wave height will decay as waves move away from source region!!! Map of Mean Wind -
Earth Science Ocean Currents May 12, 2020
High School Science Virtual Learning Earth Science Ocean Currents May 12, 2020 High School Earth Science Lesson: May 12, 2020 Objective/Learning Target: Students will understand major ocean currents and how they impact Earth. Let’s Get Started: 1. What is the difference between weather and climate? 2. What is an ocean? Let’s Get Started: Answer Key 1. Weather is local & short term, climate is regional and long term 2. The ocean is a huge body of saltwater that covers about 71 percent of the Earth's surface Lesson Activity: Directions: 1. Read through the Following slides. 2. Answer the questions on your own paper. MAJOR OCEAN CURRENTS Terms 1. Coriolis Effect movement of wind and water to the right or left that is caused by Earth’s rotation 2. upwelling vertical movement of water toward the ocean’s surface 3. surface current is an ocean current that moves water horizontally and does not reach a depth of more than 400m. 4. gyre is when major surface currents form a circular system. MAJOR OCEAN CURRENTS A current is a large volume of water flowing in a certain direction. CAUSES OF OCEAN CURRENTS 1. One cause of an ocean current is friction between wind and the ocean surface. ○ Earth’s prevailing winds influence the formation and direction of surface currents. ○ Ex: tides, waves 2. In addition to the wind, the direction surface currents flow depends on the Coriolis effect. ○ The Coriolis effect results from Earth’s rotation. It influences the direction of flow of Earth’s water and air. 3. -
Ocean Vocabulary
Mrs. Hansgen's 7th Grade Science Name Date Ocean Vocabulary wave period breaker El Nino neap tides Coriolis effect swelling whitecap tidal range trough high tide tsunami deep current crest spring tides low tide surf surface current storm surge wavelength upwelling Matching Match each definition with a word. 1. Lowest point of a wave 2. a white, foaming wave with a very steep crest that breaks in the open ocean before the wave gets close to the shore 3. A curving of a moving object from a straight path due to the Earth's rotation. 4. An ocean current formed when steady winds blow over the surface of the ocean. 5. rolling waves that move in a steady procession across the ocean 6. when the ocean tide reaches the highest point on the shoreline 7. An abnormal climate event that occurs every 2 to 7 years in the Pacific Ocean, causing changes in winds, currents, and weather patterns, that can lead to dramatic changes. 8. a wave that forms when a large volume of ocean water is suddenly moved up or down 9. The distance between two adjacent wave crests or wave troughs 10. tides with minimum daily tidal range that occur during the first and third quarters of the moon 11. Highest point of a wave 12. a process in which cold, nutrient-rich water from the deep ocean rises to the surface and replaces warm surface water 13. ocean tide at its lowest point on the shore 14. the area between the breaker zone and the shore 15. -
Circulation-Wave Coupling with a Wave Parameterization for the Idealized California Coastal Region
Circulation-Wave Coupling With a Wave Parameterization For the Idealized California Coastal Region Le Ly and Curt Collins Dept. of Oceanography Naval Postgraduate School Monterey, CA 93043 1. Introduction atmospheric model), POM (Princeton Ocean Momentum and energy transfers across the air- Model; Blumberg and Mellor, 1987), and WAM sea interface under realistic ocean conditions are wave model (Wilczak et al., 1999), and an important not only in theoretical studies, but also atmosphere-POM-WAM for the Mediterranean in many applications including marine region (Lionello et al., 1999). atmospheric and oceanic forecasts and climate Based on a new concept of oceanic turbulence modeling on all scales. Surface breaking waves and a wave breaking condition of the linear wave are believed to be an important supplier of theory, a surface wave parameterization is turbulent energy besides shear production of the developed and presented. This wave classical turbulence theory. Waves contain a parameterization with wave-dependent roughness considerable amount of momentum and energy, is tested against available data on wave- and they redistribute these quantities over great dependent turbulence dissipation, roughness distances. Wind waves supply energy for length, drag coefficient, and momentum fluxes turbulence due to breaking. Ocean waves strongly using a coupled air-wave-sea model. We also effect the air-sea system on all scale. A part of the present a circulation-wave coupling study using a energy and momentum is transferred directly wave dependent roughness (Ly and Garwood, from the atmosphere to ocean currents while 2000) and taking the wind-wave-turbulence- another part is transferred to surface waves. The current relationship into account. -
OCEANS ´09 IEEE Bremen
11-14 May Bremen Germany Final Program OCEANS ´09 IEEE Bremen Balancing technology with future needs May 11th – 14th 2009 in Bremen, Germany Contents Welcome from the General Chair 2 Welcome 3 Useful Adresses & Phone Numbers 4 Conference Information 6 Social Events 9 Tourism Information 10 Plenary Session 12 Tutorials 15 Technical Program 24 Student Poster Program 54 Exhibitor Booth List 57 Exhibitor Profiles 63 Exhibit Floor Plan 94 Congress Center Bremen 96 OCEANS ´09 IEEE Bremen 1 Welcome from the General Chair WELCOME FROM THE GENERAL CHAIR In the Earth system the ocean plays an important role through its intensive interactions with the atmosphere, cryo- sphere, lithosphere, and biosphere. Energy and material are continually exchanged at the interfaces between water and air, ice, rocks, and sediments. In addition to the physical and chemical processes, biological processes play a significant role. Vast areas of the ocean remain unexplored. Investigation of the surface ocean is carried out by satellites. All other observations and measurements have to be carried out in-situ using research vessels and spe- cial instruments. Ocean observation requires the use of special technologies such as remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), towed camera systems etc. Seismic methods provide the foundation for mapping the bottom topography and sedimentary structures. We cordially welcome you to the international OCEANS ’09 conference and exhibition, to the world’s leading conference and exhibition in ocean science, engineering, technology and management. OCEANS conferences have become one of the largest professional meetings and expositions devoted to ocean sciences, technology, policy, engineering and education. -
Ocean Wind and Current Retrievals Based on Satellite SAR Measurements in Conjunction with Buoy and HF Radar Data
remote sensing Article Ocean Wind and Current Retrievals Based on Satellite SAR Measurements in Conjunction with Buoy and HF Radar Data He Fang 1, Tao Xie 1,* ID , William Perrie 2, Li Zhao 1, Jingsong Yang 3 and Yijun He 1 ID 1 School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, China; [email protected] (H.F.); [email protected] (L.Z.); [email protected] (Y.H.) 2 Fisheries & Oceans Canada, Bedford Institute of Oceanography, Dartmouth, NS B2Y 4A2, Canada; [email protected] 3 State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, Zhejiang, China; [email protected] * Correspondence: [email protected]; Tel.: +86-255-869-5697 Received: 22 September 2017; Accepted: 13 December 2017; Published: 15 December 2017 Abstract: A total of 168 fully polarimetric synthetic-aperture radar (SAR) images are selected together with the buoy measurements of ocean surface wind fields and high-frequency radar measurements of ocean surface currents. Our objective is to investigate the effect of the ocean currents on the retrieved SAR ocean surface wind fields. The results show that, compared to SAR wind fields that are retrieved without taking into account the ocean currents, the accuracy of the winds obtained when ocean currents are taken into account is increased by 0.2–0.3 m/s; the accuracy of the wind direction is improved by 3–4◦. Based on these results, a semi-empirical formula for the errors in the winds and the ocean currents is derived. -
Cross-Shelf Transport of Pink Shrimp Larvae: Interactions of Tidal Currents, Larval Vertical Migrations and Internal Tides
Vol. 345: 167–184, 2007 MARINE ECOLOGY PROGRESS SERIES Published September 13 doi: 10.3354/meps06916 Mar Ecol Prog Ser Cross-shelf transport of pink shrimp larvae: interactions of tidal currents, larval vertical migrations and internal tides Maria M. Criales1,*, Joan A. Browder2, Christopher N. K. Mooers1, Michael B. Robblee3, Hernando Cardenas1, Thomas L. Jackson2 1Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, Florida 33149, USA 2NOAA Fisheries, Southeast Fisheries Science Center, 75 Virginia Beach Drive, Miami, Florida 33149, USA 3US Geological Survey, Center for Water and Restoration Studies, 3110 SW 9th Avenue, Ft Lauderdale, Florida 33315, USA ABSTRACT: Transport and behavior of pink shrimp Farfantepenaeus duorarum larvae were investi- gated on the southwestern Florida (SWF) shelf of the Gulf of Mexico between the Dry Tortugas spawning grounds and Florida Bay nursery grounds. Stratified plankton samples and hydrographic data were collected at 2 h intervals at 3 stations located on a cross-shelf transect. At the Marquesas station, midway between Dry Tortugas and Florida Bay, internal tides were recognized by anom- alously cool water, a shallow thermocline with strong density gradients, strong current shear, and a high concentration of pink shrimp larvae at the shallow thermocline. Low Richardson numbers occurred at the pycnocline depth, indicating vertical shear instability and possible turbulent transport from the lower to the upper layer where myses and postlarvae were concentrated. Analysis of verti- cally stratified plankton suggested that larvae perform vertical migrations and the specific behavior changes ontogenetically; protozoeae were found deeper than myses, and myses deeper than postlar- vae. -
Proceedings: Twentieth Annual Gulf of Mexico Information Transfer Meeting
OCS Study MMS 2001-082 Proceedings: Twentieth Annual Gulf of Mexico Information Transfer Meeting December 2000 U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region OCS Study MMS 2001-082 Proceedings: Twentieth Annual Gulf of Mexico Information Transfer Meeting December 2000 Editors Melanie McKay Copy Editor Judith Nides Production Editor Debra Vigil Editor Prepared under MMS Contract 1435-00-01-CA-31060 by University of New Orleans Office of Conference Services New Orleans, Louisiana 70814 Published by New Orleans U.S. Department of the Interior Minerals Management Service October 2001 Gulf of Mexico OCS Region iii DISCLAIMER This report was prepared under contract between the Minerals Management Service (MMS) and the University of New Orleans, Office of Conference Services. This report has been technically reviewed by the MMS and approved for publication. Approval does not signify that contents necessarily reflect the views and policies of the Service, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. It is, however, exempt from review and compliance with MMS editorial standards. REPORT AVAILABILITY Extra copies of this report may be obtained from the Public Information Office (Mail Stop 5034) at the following address: U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region Public Information Office (MS 5034) 1201 Elmwood Park Boulevard New Orleans, Louisiana 70123-2394 Telephone Numbers: (504) 736-2519 1-800-200-GULF CITATION This study should be cited as: McKay, M., J. Nides, and D. Vigil, eds. 2001. Proceedings: Twentieth annual Gulf of Mexico information transfer meeting, December 2000.