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1. |
The potential of satellite‐based radar altimeters |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 81-87
C. N. K. Mooers,
D. E. Barrick,
R. E. Cheney,
D. B. Lame,
J. G. Marsh,
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摘要:
Seasat is the only dedicated, multisensor oceanographic satellite to have ever flown. Although the mission lasted for only 3 months in 1978, it returned an enormous harvest of unique and valuable data that are still in the early stages o f analysis. Its sensor complement included a scatterometer for surface winds, a passive microwave radiometer for sea surface thermal measurements, a synthetic aperture radar system for ocean surface imaging, and the radar altimeter. The altimeter provides information on significant wave height, surface wind speed, and above all, the topography of the sea surface. This topography is of prime interest to ocean circulation studies because its horizontal gradient, after removal of the geoidal signal, is proportional to the surface geostrophic current, the principal circulation component.
ISSN:0002-8606
DOI:10.1029/EO065i010p00081
年代:1984
数据来源: WILEY
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2. |
Lagrangian studies of deep ocean currents |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 82-83
T. Rossby,
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摘要:
It is now more than 10 years since the first experiment using subsurface drifters (so‐called Sofar floats) took place in the Mid‐Ocean Dynamics Experiment (Mode). Since then they have been applied in a series of exploratory studies culminating in the Polymode Local Dynamics Experiment (LDE), and more recently along 55°W in a study of the North Atlantic subtropical gyre in a region well removed from the dynamics of western boundary regions. These neutrally buoyant instruments, which can be ballasted to drift with the waters at pressures up to 2000 dbars (meters), are tracked acoustically over long periods of time (months to years). Conceptually the floats may be thought of as large molecules, fluid parcels whose pathways and speeds are explicitly known. The structure of their trajectories often yields surprisingly detailed information on the horizontal structure of the velocity field. When used in clusters they can tell us much about the mean field and the dispersive properties of the region. This article provides a brief retrospective o f what we have learned in the 10 years since their first application in Mode. We begin with a brief descripion of the Sofar float techno
ISSN:0002-8606
DOI:10.1029/EO065i010p00082
年代:1984
数据来源: WILEY
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3. |
Quantifying submarine hydrothermal fluxes |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 83-88
Michael L. Bender,
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摘要:
Many oceanographers believe that the chemical fluxes associated with deep sea hydrothermal processes are large and geochemically important, but quantifying these fluxes is proving difficult. Seawater‐basalt exchange takes place in high‐temperature hydrothermal systems at the very axis of seafloor spreading, as observed at the Galapagos Spreading Center [Corliss et al., 1979], and the East Pacific Rise at 13°N and 21°N [Michard et al.1982;RISE Project Group, 1980]. It also takes place in the lower temperature hydrothermal systems, which are ubiquitous on the flanks of mid‐ocean ridges, until sedimentation, and void‐filling in basalt, seal the hydrothermal systems at crustal ages between 10 and 80 m.y. [e.g.,Anderson et a
ISSN:0002-8606
DOI:10.1029/EO065i010p00083
年代:1984
数据来源: WILEY
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4. |
No olivine in the mantle? |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 84-84
Anonymous,
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摘要:
Perhaps the most impressive factors in D.L. Anderson's analysis of new physical models of the earth are contributions from the numerous disciplines of modern geophysics, including 3‐dimensional seismological observations, high‐pressure experiments, highly precise isotope analyses, and studies of other solar system bodies [Science, 223, pp. 347–355, 1984].The results? In short, there are the “ins” and the “outs.” For example, the basalt‐eclogite transition is back in fashion, whereas the notion of an olivine‐rich deep mantle assemblage is no longer in fashion. This analogy is not to be construed as any return to old, preplate‐tectonic concepts. Modern research, in the purest sense, is forcing “a reexamination of some l
ISSN:0002-8606
DOI:10.1029/EO065i010p00084-01
年代:1984
数据来源: WILEY
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5. |
Negev: Land, Water, and Life in a Desert Environment |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 85-88
William Back,
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摘要:
In view of the continuing increased concern about the extreme fragility of deserts and desert margins, Negev provides a timely discussion of land‐use practices compatible with the often conflicting goals of preservation and development. The success o f agricultural and hydrologic experiments in the Negev desert of Israel offers hope to the large percentage of the world's population that lives with an unacceptably low quality of life in desert margins. Deserts are the one remaining type of open space that, with proper use, has the potential for alleviating the misery often associated with expanding population.In addition to the science in the book, the author repeatedly reinforces the concept that “western civilization is inextricably bound to the Negev and its environs, from which it has drawn, via its desert‐born religions—Judasium, Christianity, and Islam—many of the mores and concepts, and much of the imagery and love of the desert, including man's relation to nature and to ‘God’.” Deserts often are erroneously perceived to be areas of no water: In reality, these are areas in which a little rainfall occurs sporadically and unpredictably over time. This meager water supply can be meticulously garnered to produce nutritious c
ISSN:0002-8606
DOI:10.1029/EO065i010p00085
年代:1984
数据来源: WILEY
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6. |
Science and policy on Capitol Hill |
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Eos, Transactions American Geophysical Union,
Volume 65,
Issue 10,
1984,
Page 90-90
Arthur B. Weissman,
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摘要:
I spent my year as the 1982–1983 AGU Congressional Science Fellow as legislative assistant to Sen. Christopher J. Dodd (D‐Conn.), covering environment and energy issues. I offer this final report of my year not only for potential Congressional Science Fellows but for all readers ofEoswho may want to contribute to science policy making (but are afraid to try).My primary goal was to get a broad exposure to issues, organizations, people, and the legislative process; this I achieved beyond my expectation. Congress, remarkably, is set up like a vast marketplace: There are vendors (the lobbyists and interest groups) and consumers (the constituents), and each group makes its desires known to the members of Congress, who act as brokers. Issues are strewn about like so many fish—some stale and rancid; others fresh and meaty, the catch of the day. And there is no real respite: Problems requiring a response (if not a solution) will seek out even the most diffident Member or st
ISSN:0002-8606
DOI:10.1029/EO065i010p00090-01
年代:1984
数据来源: WILEY
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