Measurements Of Ocean Currents

Measuring Ocean Currents: Tools, Technologies, and Data covers all major aspects of ocean current measurements in view of the implications of ocean currents on changing climate, increasing pollution levels, and offshore engineering activities. Although more than 70% of the Earth is covered by ocean, there is limited information on the countless fine- to large-scale water motions taking place within them. This book fills that information gap as the first work that summarizes the state-of-the-art methods and instruments used for surface, subsurface, and abyssal ocean current measurements. Readers of this book will find a wealth of information on Lagrangian measurements, horizontal mapping, imaging, Eulerian measurements, and vertical profiling techniques. In addition, the book describes modern technologies for remote measurement of ocean currents and their signatures, including HF Doppler radar systems, satellite-borne sensors, ocean acoustic tomography, and more. Crucial aspects of ocean currents are described in detail as well, including dispersion of effluents discharged into the sea and transport of beneficial materials—as well as environmentally hazardous materials—from one region to another. The book highlights several important practical applications, showing how measurements relate to climate change and pollution levels, how they affect coastal and offshore engineering activities, and how they can aid in tsunami detection. Coverage of measurement, mapping and profiling techniques Descriptions of technologies for remote measurement of ocean currents and their signatures Reviews crucial aspects of ocean currents, including special emphasis on the planet-spanning thermohaline circulation, known as the ocean's "conveyor belt," and its crucial role in climate change

Mean currents and density were measured off Point Sur, California in March 1989 using Pegasus and CTD instruments. Velocity, temperature, salinity, and density fields are examined to discern the structure of the California and Davidson currents. Velocities measured by Pegasus are compared to flow fields derived from geostrophy. The Davidson Current flows poleward at the surface in its winter configuration despite northerly winds and coastal upwelling which normally drive the flow subsurface in the summer months.

Ocean Currents: Physical Drivers in a Changing World opens with a general introduction to the character, measurement, and simulation of ocean currents, leading to a physical and dynamical framework for understanding the wide variety of flows encountered in the oceans. The book comprises chapters covering distinct aspects of contrasting ocean currents: broad and slow, deep and shallow, narrow and swift, large scale and small scale, low latitudes and high latitudes, and moving in horizontal and vertical planes. Through this approach the authors cover a wide range of applications, from local to global, with considerable geographical context. Provides analyses of ocean observations and numerical model simulations, highlighting the pathways and drift associated with ocean currents, around the World Ocean, linked to online exercises for instructors and students that extend this perspective Presents applications to natural phenomena, showing how ocean currents shape marine ecosystems, helping researchers understand the distribution and adaptation of life in the oceans Addresses societal challenges, specifically how ocean currents disperse pollutants (e.g. plastic) from coastal sources and how the global ocean circulation is central to our changing climate, helping students and researchers develop an interdisciplinary approach to global environmental change

Ocean Currents is a derivative of the Encyclopedia of Ocean Sciences, 2nd Edition and serves as an important reference on current ocean current knowledge and expertise in one convenient and accessible source. Its selection of articles—all written by experts in their field—focuses on key ocean current concepts. Its topics include ocean currents, the circulation of deep water, the contrasting circulations of the seas, the circulation in fjords, estuaries and the effects of rivers, and the intermittency and variability of the oceans. Ocean Currents serves as an ideal reference for topical research. References related articles on ocean currents to facilitate further research Richly illustrated with figures and tables that aid in understanding key concepts Includes an introductory overview of ocean currents and then explores each topic in detail, making it useful to experts and graduate-level researchers Topical arrangement makes it the perfect desk reference

Ocean currents were measured in the central northeast Pacific, from 30 degrees N to 40 degrees N and 140 degrees W to 150 degrees W, with nine arrays of moored current meters during autumn 1973. Current meter records at depths from 700 m to 5420 m were analyzed to determine the characteristics of intermediate and deep currents within the central northeast Pacific. The currents in this region have very low speeds which generally decrease with increasing depth. Contributions to the time-dependent currents are primarily from oscillatory motions at the local inertial frequencies and the semidiurnal tidal frequency. Spectral analysis indicates that tidal frequency motion is essentially due to baroclinic internal tides and not barotropic surface tides.