Effects of the Kuroshio Current on Copepod Assemblages in Taiwan
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Fronts in the World Ocean's Large Marine Ecosystems. ICES CM 2007
- 1 - This paper can be freely cited without prior reference to the authors International Council ICES CM 2007/D:21 for the Exploration Theme Session D: Comparative Marine Ecosystem of the Sea (ICES) Structure and Function: Descriptors and Characteristics Fronts in the World Ocean’s Large Marine Ecosystems Igor M. Belkin and Peter C. Cornillon Abstract. Oceanic fronts shape marine ecosystems; therefore front mapping and characterization is one of the most important aspects of physical oceanography. Here we report on the first effort to map and describe all major fronts in the World Ocean’s Large Marine Ecosystems (LMEs). Apart from a geographical review, these fronts are classified according to their origin and physical mechanisms that maintain them. This first-ever zero-order pattern of the LME fronts is based on a unique global frontal data base assembled at the University of Rhode Island. Thermal fronts were automatically derived from 12 years (1985-1996) of twice-daily satellite 9-km resolution global AVHRR SST fields with the Cayula-Cornillon front detection algorithm. These frontal maps serve as guidance in using hydrographic data to explore subsurface thermohaline fronts, whose surface thermal signatures have been mapped from space. Our most recent study of chlorophyll fronts in the Northwest Atlantic from high-resolution 1-km data (Belkin and O’Reilly, 2007) revealed a close spatial association between chlorophyll fronts and SST fronts, suggesting causative links between these two types of fronts. Keywords: Fronts; Large Marine Ecosystems; World Ocean; sea surface temperature. Igor M. Belkin: Graduate School of Oceanography, University of Rhode Island, 215 South Ferry Road, Narragansett, Rhode Island 02882, USA [tel.: +1 401 874 6533, fax: +1 874 6728, email: [email protected]]. -
Kinematic and Dynamic Scaling of Copepod Swimming
fluids Review Kinematic and Dynamic Scaling of Copepod Swimming Leonid Svetlichny 1,* , Poul S. Larsen 2 and Thomas Kiørboe 3 1 I.I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, Str. B. Khmelnytskogo, 15, 01030 Kyiv, Ukraine 2 DTU Mechanical Engineering, Fluid Mechanics, Technical University of Denmark, Building 403, DK-2800 Kgs. Lyngby, Denmark; [email protected] 3 Centre for Ocean Life, Danish Technical University, DTU Aqua, Building 202, DK-2800 Kgs. Lyngby, Denmark; [email protected] * Correspondence: [email protected] Received: 30 March 2020; Accepted: 6 May 2020; Published: 11 May 2020 Abstract: Calanoid copepods have two swimming gaits, namely cruise swimming that is propelled by the beating of the cephalic feeding appendages and short-lasting jumps that are propelled by the power strokes of the four or five pairs of thoracal swimming legs. The latter may be 100 times faster than the former, and the required forces and power production are consequently much larger. Here, we estimated the magnitude and size scaling of swimming speed, leg beat frequency, forces, power requirements, and energetics of these two propulsion modes. We used data from the literature together with new data to estimate forces by two different approaches in 37 species of calanoid copepods: the direct measurement of forces produced by copepods attached to a tensiometer and the indirect estimation of forces from swimming speed or acceleration in combination with experimentally estimated drag coefficients. Depending on the approach, we found that the propulsive forces, both for cruise swimming and escape jumps, scaled with prosome length (L) to a power between 2 and 3. -
Strengthening of the Kuroshio Current by Intensifying Tropical Cyclones
RESEARCH OCEAN CIRCULATION geostrophic adjustment, was first considered by Rossby in 1938 (19) and has since been in- Strengthening of the Kuroshio current by intensifying vestigated in a variety of contexts both linear and nonlinear (20–23). Common to all those tropical cyclones studies is that the flows in question hold less energy at their end states than they do initially, Yu Zhang1*, Zhengguang Zhang1, Dake Chen2,3, Bo Qiu4, Wei Wang1 and energy is dispersed in the form of inertial gravity waves ( 19, 24). It is therefore antici- A positive feedback mechanism between tropical cyclones (TCs) and climate warming can be pated that eddies under the influence of strong seen by examining TC-induced energy and potential vorticity (PV) changes of oceanic geostrophic storms may be perturbed and subsequently eddies. We found that substantial dissipation of eddies, with a strong bias toward dissipation of undertake adjustment processes that atten- anticyclonic eddies, is directly linked to TC activity. East of Taiwan, where TCs show a remarkable uate them (25). intensifying trend in recent decades, the ocean exhibits a corresponding upward trend of positive Evidence continues to mount that both PV anomalies. Carried westward by eddies, increasing numbers of positive PV anomalies impinge on mechanisms described above exist, working the Kuroshio current, causing the mean current to accelerate downstream. This acts in opposition together to reduce the strength of anticyclonic to decreasing basin-scale wind stress and has a potentially important warming impact on the eddies but acting against each other in chang- extratropical ocean and climate. ing cyclonic eddies. Which process dominates, and what overall influence the TCs exert on an underlying eddy field, remains unclear. -
UC San Diego UC San Diego Previously Published Works
UC San Diego UC San Diego Previously Published Works Title Integrated molecular and morphological biogeography of the calanoid copepod family Eucalanidae Permalink https://escholarship.org/uc/item/3hv940x9 Journal Deep-Sea Research Part II: Topical Studies in Oceanography, 57(24-26) ISSN 0967-0645 Authors Goetze, E Ohman, MD Publication Date 2010-12-01 DOI 10.1016/j.dsr2.2010.09.014 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Author's personal copy Deep-Sea Research II 57 (2010) 2110–2129 Contents lists available at ScienceDirect Deep-Sea Research II journal homepage: www.elsevier.com/locate/dsr2 Integrated molecular and morphological biogeography of the calanoid copepod family Eucalanidae Erica Goetze a,n, Mark D. Ohman b a Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA b Integrative Oceanography Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0218, USA article info abstract Article history: Species range information forms the empirical data of pelagic biogeography. Early descriptions of Received 18 September 2010 canonical zooplankton distributions in the Pacific Ocean were based, in part, on distributional data from Accepted 18 September 2010 the planktonic copepod family Eucalanidae. A large-scale molecular survey of this group, covering Available online 21 September 2010 Atlantic, Pacific, and Indian Oceans (1295 individuals), increased the total diversity from 24 to 39 Keywords: -
Author's Personal Copy
Author's personal copy Deep-Sea Research II 57 (2010) 2110–2129 Contents lists available at ScienceDirect Deep-Sea Research II journal homepage: www.elsevier.com/locate/dsr2 Integrated molecular and morphological biogeography of the calanoid copepod family Eucalanidae Erica Goetze a,n, Mark D. Ohman b a Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA b Integrative Oceanography Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0218, USA article info abstract Article history: Species range information forms the empirical data of pelagic biogeography. Early descriptions of Received 18 September 2010 canonical zooplankton distributions in the Pacific Ocean were based, in part, on distributional data from Accepted 18 September 2010 the planktonic copepod family Eucalanidae. A large-scale molecular survey of this group, covering Available online 21 September 2010 Atlantic, Pacific, and Indian Oceans (1295 individuals), increased the total diversity from 24 to 39 Keywords: evolutionarily significant units (ESUs). New biogeographies are presented here for 18 lineages within 10 Pelagic biogeography described species in the genera Subeucalanus, Pareucalanus, and Rhincalanus. Integration of molecular Cryptic species and morphological data on diversity and distribution resulted in three primary outcomes: (1) the Mitochondrial 16S rRNA morphological species was confirmed to be valid, and the biogeographic distribution remains largely Nuclear internal transcribed spacer 2 unchanged from prior reports, (2) the species was found to contain multiple ESUs, each of which has a Phylogeography more restricted distribution than the parent taxon, and (3) the species was found to contain multiple ESUs, whose biogeographic distributions remain unclear. -
Lecture 4: OCEANS (Outline)
LectureLecture 44 :: OCEANSOCEANS (Outline)(Outline) Basic Structures and Dynamics Ekman transport Geostrophic currents Surface Ocean Circulation Subtropicl gyre Boundary current Deep Ocean Circulation Thermohaline conveyor belt ESS200A Prof. Jin -Yi Yu BasicBasic OceanOcean StructuresStructures Warm up by sunlight! Upper Ocean (~100 m) Shallow, warm upper layer where light is abundant and where most marine life can be found. Deep Ocean Cold, dark, deep ocean where plenty supplies of nutrients and carbon exist. ESS200A No sunlight! Prof. Jin -Yi Yu BasicBasic OceanOcean CurrentCurrent SystemsSystems Upper Ocean surface circulation Deep Ocean deep ocean circulation ESS200A (from “Is The Temperature Rising?”) Prof. Jin -Yi Yu TheThe StateState ofof OceansOceans Temperature warm on the upper ocean, cold in the deeper ocean. Salinity variations determined by evaporation, precipitation, sea-ice formation and melt, and river runoff. Density small in the upper ocean, large in the deeper ocean. ESS200A Prof. Jin -Yi Yu PotentialPotential TemperatureTemperature Potential temperature is very close to temperature in the ocean. The average temperature of the world ocean is about 3.6°C. ESS200A (from Global Physical Climatology ) Prof. Jin -Yi Yu SalinitySalinity E < P Sea-ice formation and melting E > P Salinity is the mass of dissolved salts in a kilogram of seawater. Unit: ‰ (part per thousand; per mil). The average salinity of the world ocean is 34.7‰. Four major factors that affect salinity: evaporation, precipitation, inflow of river water, and sea-ice formation and melting. (from Global Physical Climatology ) ESS200A Prof. Jin -Yi Yu Low density due to absorption of solar energy near the surface. DensityDensity Seawater is almost incompressible, so the density of seawater is always very close to 1000 kg/m 3. -
Global Ocean Surface Velocities from Drifters: Mean, Variance, El Nino–Southern~ Oscillation Response, and Seasonal Cycle Rick Lumpkin1 and Gregory C
JOURNAL OF GEOPHYSICAL RESEARCH: OCEANS, VOL. 118, 2992–3006, doi:10.1002/jgrc.20210, 2013 Global ocean surface velocities from drifters: Mean, variance, El Nino–Southern~ Oscillation response, and seasonal cycle Rick Lumpkin1 and Gregory C. Johnson2 Received 24 September 2012; revised 18 April 2013; accepted 19 April 2013; published 14 June 2013. [1] Global near-surface currents are calculated from satellite-tracked drogued drifter velocities on a 0.5 Â 0.5 latitude-longitude grid using a new methodology. Data used at each grid point lie within a centered bin of set area with a shape defined by the variance ellipse of current fluctuations within that bin. The time-mean current, its annual harmonic, semiannual harmonic, correlation with the Southern Oscillation Index (SOI), spatial gradients, and residuals are estimated along with formal error bars for each component. The time-mean field resolves the major surface current systems of the world. The magnitude of the variance reveals enhanced eddy kinetic energy in the western boundary current systems, in equatorial regions, and along the Antarctic Circumpolar Current, as well as three large ‘‘eddy deserts,’’ two in the Pacific and one in the Atlantic. The SOI component is largest in the western and central tropical Pacific, but can also be seen in the Indian Ocean. Seasonal variations reveal details such as the gyre-scale shifts in the convergence centers of the subtropical gyres, and the seasonal evolution of tropical currents and eddies in the western tropical Pacific Ocean. The results of this study are available as a monthly climatology. Citation: Lumpkin, R., and G. -
Site Selection of Ocean Current Power Generation from Drifter Measurements
SITE SELECTION OF CURRENT POWER GENERATION 1 Site selection of ocean current power generation from drifter 2 measurements 3 4 Yu-Chia Chang1*, Peter C. Chu2, Ruo-Shan Tseng3 5 6 1 Department of Marine Biotechnology and Resources, National Sun Yat-sen University, 7 Kaohsiung 80424, Taiwan 8 2 Naval Ocean Analysis and Prediction Laboratory, Naval Postgraduate School, Monterey, 9 CA 93943, USA 10 3 Department of Oceanography, National Sun Yat-sen University, Kaohsiung 80424, 11 Taiwan 12 13 14 December 2014 15 16 17 18 19 20 21 ----------------------------------------- 22 *Corresponding author. E-mail: [email protected], Fax: 886-7-5255033 1 SITE SELECTION OF CURRENT POWER GENERATION 23 Abstract 24 Site selection of ocean current power generation is usually based on numerical ocean 25 calculation models. In this study however, the selection near the coast of East Asia is 26 optimally from the Surface Velocity Program (SVP) data using the bin average method. 27 Japan, Vietnam, Taiwan, and Philippines have suitable sites for the development of ocean 28 current power generation. In these regions, the average current speeds reach 1.4, 1.2, 1.1, 29 and 1.0 m s-1, respectively. Vietnam has a better bottom topography to develop the current 30 power generation. Taiwan and Philippines also have good conditions to build plants for 31 generating ocean current power. Combined with the four factors of site selection (near 32 coast, shallow seabed, stable flow velocity, and high flow speed), the waters near 33 Vietnam is most suitable for the development of current power generation. -
Phase Synchronisation in the Kuroshio Current System Ann Kristin Klose1, René M
https://doi.org/10.5194/os-2019-96 Preprint. Discussion started: 4 September 2019 c Author(s) 2019. CC BY 4.0 License. Phase Synchronisation in the Kuroshio Current System Ann Kristin Klose1, René M. van Westen2, and Henk A. Dijkstra2,3 1ICBM, Carl von Ossietzky University Oldenburg, Oldenburg, Germany 2Institute for Marine and Atmospheric research Utrecht, Department of Physics, Utrecht University, Utrecht, the Netherlands 3Center for Complex Systems Studies, Utrecht University, Utrecht, the Netherlands Correspondence to: Henk Dijkstra <[email protected]> Abstract. The Kuroshio Current System in the North Pacific displays path transitions on a decadal time scale. It is known that both internal variability involving barotropic and baroclinic instabilities and remote Rossby waves induced by North Pacific wind-stress anomalies are involved in these path transitions. However, the precise coupling of both processes and its consequences for the dominant decadal transition time scale are still under discussion. Here, we analyse the output of a 5 multi-centennial long high-resolution global climate model simulation and study phase synchronisation between Pacific zonal wind-stress anomalies and Kuroshio Current System path variability. We apply the Hilbert transform technique to determine the phase and find epochs where such phase synchronisation appears. The physics of this synchronisation is shown to occur through the effect of the vertical motion of isopycnals, as induced by the propagating Rossby waves, on the instabilities of the Kuroshio Current System. 10 1 Introduction The Kuroshio Current System (KCS) in the North Pacific plays an important role in climate through its meridional heat transport (Hu et al., 2015). -
Australian Marine Zooplankton-Calanoid Copepods Part 2
Phylum Arthropoda Order Calanoida Candacia truncata Family Candaciidae Dana, 1849 Size ♂ Male: 1.87 – 2.11 mm scale: mm A1 P5 Male • Geniculate right A1 has a series of stout proximal segments followed by a thin section, then a broad club 1.0 section, beyond club section, segment 16 has a finger-like protrusion which is difficult to observe clearly; fused segments 17 and 18 are characteristically curved • Last prosome somite symmetrical with sharp points • P5 left segment 4 with 3 setae; right P5 not chelate and segment 3 urosome terminates in long plumose setae • Urosome and caudal rami symmetrical with no projections Ecology • Specialised predator, grasping prey with large and robust maxillae • Larvaceans are major prey item Source Boxshall & Halsey (2004) Bradford-Grieve (1999) Chen and Zhang (1965) Conway (2003) Tanaka (1935) ; Chen & Zhang (1965) Greenwood (1978) Razouls et al. (2010) preserved specimen Tanaka (1935) (Full reference available at http://www.imas.utas.edu.au/zooplankton/references ) Compiled: C. H. Davies & A. S. Slotwinski 2012 Images: AusCPR Verified: K. M. Swadling 2013 Phylum Arthropoda Centropages australiensis Order Calanoida Fairbridge, 1944 Family Centropagidae Synonyms None ♀ exopod 2 spine-like scale: mm process Size Female: 1.43 mm 1.0 Genus notes • Small to medium size • Cephalosome and pedigerous somite 1 are fused (fusion lines visible on sides) • Single naupliar eye P5 • Lateral corners of posterior prosome often end in asymmetrical points • Characteristic undulating edge on last prosomal somite between -
Three-Dimensional Simulations of Wind Effects on Green Island Wake
water Article Three-Dimensional Simulations of Wind Effects on Green Island Wake Tien-Hung Hou 1, Jen-Yi Chang 2, Chia-Cheng Tsai 1,3,4,* and Tai-Wen Hsu 4 1 Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 811213, Taiwan; [email protected] 2 General Education Center, Tainan University of Technology, Tainan 71002, Taiwan; [email protected] 3 Department of Marine Environment and Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan 4 Center of Excellence for Ocean Engineering, National Taiwan Ocean University, Keelung 20224, Taiwan; [email protected] * Correspondence: [email protected] Received: 17 September 2020; Accepted: 26 October 2020; Published: 29 October 2020 Abstract: The aim of the present study is to apply the three-dimensional Princeton Ocean Model to study the wind effects on Kuroshio-induced island wake in the lee of Green Island, Taiwan. Numerical results indicate that the effect of NE winds squeezes the Kuroshio-induced island vortex street close to the coast and the SW winds tend to push the island vortex street farther away from the coast. The simulated vortex streets are analyzed by the dimensionless spatial lengths to quantify the prescribed feature. By comparing the three-dimensional results with different wind conditions, the Ekman transports are observed and the influence depths of wind effects are studied. Additionally, some cold eddies are found in temperature fields resulting from numerical simulations. These results are in qualitative agreement with field measurements and satellite images. Keywords: 3D ocean modeling; Kuroshio; island wake; wind effect; Ekman transport 1. -
The Kuroshio - Its Physical Aspect and Roles in Kagoshima’S Nature and Culture - Hirohiko NAKAMURA
KAWAI, K., TERADA, R. and KUWAHARA, S. (eds): The Islands of Kagoshima Kagoshima University Research Center for the Pacific Islands, 15 March 2013 Chapter 20 The Kuroshio - Its Physical Aspect and Roles in Kagoshima’s Nature and Culture - Hirohiko NAKAMURA 1. Introduction The author wrote this article to provide general he Kuroshio is one of the largest currents in and useful information about the Kuroshio to per- Tthe oceans of the world, and flows northward sons without any previous knowledge of the Kuro- along the western boundary of the North Pacific shio, such as visitors from foreign countries. This Ocean. Along its path, the Kuroshio flows through first article provides general explanations of the the coastal seas of Kagoshima Prefecture, which Kuroshio from the physical oceanographic point are located at the most upstream stretch of the cur- of view, and then describes regional features of the rent as it passes through the waters south of the current in the seas of Kagoshima, such as the spa- main islands of Japan. As a result, numerous as- tial patterns, temporal variations, water properties pects of Kagoshima’s culture and natural environ- and water colors, before finally focusing on some ment are closely related to the Kuroshio. For ex- effects of the Kuroshio on Kagoshima’s natural ample, coral reef habitats extend northward along environment, such as the region’s ecosystem, fish- the Kuroshio’s path as far as the small islands south ing industries, and regional climate. A number of of Kyushu, where the subtropical seawater it trans- historical events that connect the region with the ports from the southern latitudes is warm enough Kuroshio are added as topics in each section.