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Large-scale phenomena, chapter 3, part D
Oceanic phenomena with horizontal scales from approximately 100 km up to the widths of the oceans themselves are examined. Data include: shape of geoid, quasi-stationary anomalies due to spatial variations in sea density and steady current systems, and the time dependent variations due to tidal and meteorological forces and to varying currents
Science opportunities from the Topex/Poseidon mission
The U.S. National Aeronautics and Space Administration (NASA) and the French Centre National d'Etudes Spatiales (CNES) propose to conduct a Topex/Poseidon Mission for studying the global ocean circulation from space. The mission will use the techniques of satellite altimetry to make precise and accurate measurements of sea level for several years. The measurements will then be used by Principal Investigators (selected by NASA and CNES) and by the wider oceanographic community working closely with large international programs for observing the Earth, on studies leading to an improved understanding of global ocean dynamics and the interaction of the ocean with other processes influencing life on Earth. The major elements of the mission include a satellite carrrying an altimetric system for measuring the height of the satellite above the sea surface; a precision orbit determination system for referring the altimetric measurements to geodetic coordinates; a data analysis and distribution system for processing the satellite data, verifying their accuracy, and making them available to the scientific community; and a principal investigator program for scientific studies based on the satellite observations. This document describes the satellite, its sensors, its orbit, the data analysis system, and plans for verifying and distributing the data. It then discusses the expected accuracy of the satellite's measurements and their usefulness to oceanographic, geophysical, and other scientific studies. Finally, it outlines the relationship of the Topex/Poseidon mission to other large programs, including the World Climate Research Program, the U.S. Navy's Remote Ocean Sensing System satellite program and the European Space Agency's ERS-1 satellite program
The importance of altimeter and scatterometer data for ocean prediction
The prediction of ocean circulation using satellite altimeter data is discussed. Three classes of oceanic response to atmospheric forcing are outlined and examined. Storms, surface waves, eddies, and ocean currents were evaluated in terms of forecasting time requirements. Scatterometer and radiometer applications to ocean prediction are briefly reviewed
Pacific herring, Clupea harengus pallasi, studies in San Francisco and Tomales Bays, April 1989 to March 1990
Herring schools were surveyed hydroacoustically in
San Francisco Bay from early November 1989 through
mid March 1990. Seven large schools (>1000 tons) and
two smaller ones were detected. The total acoustic
biomass estimate based on visual integration was
58,100 tons. Merging with the independent spawn
escapement estimate yielded a "best" estimate of
64,500 tons.
Sixty-three samples, containing 10,239 herring, were
collected. Patterns evident in prior seasons
continue. Larger, older fish continue to dominate
early season schools. Males continue to be
numerically superior during the first half of the
season. Mean size and weight at age suggest
conditions following the 1988-89 season were not
favorable for growth.
Contrary to forecasts, the 1988 year class
recruitment strength was high; second only to the
1982 year class. Although still being validated,
forecasts suggest the 1989 year class will be strong
and the 1990 year class will be extremely weak. (64pp.
Report from the Tri-Agency Cosmological Simulation Task Force
The Tri-Agency Cosmological Simulations (TACS) Task Force was formed when
Program Managers from the Department of Energy (DOE), the National Aeronautics
and Space Administration (NASA), and the National Science Foundation (NSF)
expressed an interest in receiving input into the cosmological simulations
landscape related to the upcoming DOE/NSF Vera Rubin Observatory (Rubin),
NASA/ESA's Euclid, and NASA's Wide Field Infrared Survey Telescope (WFIRST).
The Co-Chairs of TACS, Katrin Heitmann and Alina Kiessling, invited community
scientists from the USA and Europe who are each subject matter experts and are
also members of one or more of the surveys to contribute. The following report
represents the input from TACS that was delivered to the Agencies in December
2018.Comment: 36 pages, 3 figures. Delivered to NASA, NSF, and DOE in Dec 201
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