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1. |
The Upper Atmosphere Research Satellite |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1867-1878
Carl A. Reber,
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摘要:
The Upper Atmosphere Research Satellite (UARS) [Burr and Reber, 1985;Reber, 1985] is an important new National Aeronautics and Space Administration program aimed at improving our knowledge of the stratosphere, mesosphere, and lower thermosphere, emphasizing those levels that are known to be particularly susceptible to change by external agents. Using a combination of measurements and theoretical studies, UARS will provide a focus for resolving scientific questions about the chemistry, dynamics, and overall energy balance of the upper atmosphere.
ISSN:0002-8606
DOI:10.1029/90EO00373
年代:1990
数据来源: WILEY
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2. |
Hydrologic Sciences Report |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1869-1869
Anonymous,
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摘要:
The National Research Council's Water Science and Technology Board established a Committee on Opportunities in the Hydrologic Sciences, chaired by AGU Past President Peter S. Eagleson, Massachusetts Institute of Technology, Cambridge. A report outlining the plans for the committee, prepared by Eagleson, was published inEos, August 30, 1988 (pp. 817 and 821). A follow‐up article, “Profiles of the Hydrologic Community,” published inEos, May 27, 1989 (p. 612), summarized the results of a questionnaire circulated among the 2000‐plus members of the AGU Hydrology Section. The following article by Committee Chairman Eagleson brings readers u p to date on the results of the NAS Committee's study and announces availability of their
ISSN:0002-8606
DOI:10.1029/EO071i051p01869
年代:1990
数据来源: WILEY
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3. |
AGU Planet Earth Committee Report: Part II: Interior and Crust |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1870-1870
Peter J. Wyllie,
William M. Kaula,
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PDF (424KB)
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摘要:
The Earth's mantle, core, and crust comprise 99.98% of its mass. The mantle, making up the bulk of the mass at 70% and composed of higher density rocks (rich in magnesium silicates, plus some iron silicates), extends an average of 15–2900 km deep. The core is the center of the Earth, 2900–6370 km deep, composed mainly of molten iron. The crust is the outermost layer of the solid Earth, composed of lower density rocks (rich in silica and aluminum and calcium silicates) 6–40 km
ISSN:0002-8606
DOI:10.1029/90EO00374
年代:1990
数据来源: WILEY
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4. |
Implementation |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1871-1871
Adam M. Dziewonski,
William M. Kaula,
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摘要:
The problem‐oriented discussions in this series mention many observations, experiments, and modelings that are needed to carry out the goals of the Planet Earth Initiative. The next logical step would be to compile from these mentions an enumeration of measurables (for example, cloud coverage and ocean surface temperature), with a view to specifying the instruments, platforms, spacings, frequencies, etc., at which these measurements should be made. This step has already been taken for significant fractions of the problems discussed. Tables 1 and 2 are outlines of such a compilation, the most comprehensive but not the most detailed, drawn from the 1988 National Research Council/Space Science Board report,Space Science in the Twenty‐First Century: Mission to Planet Earth. Its emphasis is on the global approach, and some might argue that 10,000 “simple ground installations” are too few for such efforts as studies of crustal
ISSN:0002-8606
DOI:10.1029/EO071i051p01871
年代:1990
数据来源: WILEY
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5. |
Submarine groundwater discharge |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1872-1872
Anonymous,
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摘要:
Measurement of groundwater discharge to rivers, lakes, estuaries, and oceans was the subject of a special session at the meeting of the North American Benthological Society, held at Virginia Polytechnic Institute and State University, Blacksburg, Va., May 22–25, 1990. The meeting was attended by more than 40 marine and aquatic ecologists, hydrologists, environmental engineers, and geophysicists and was organized by G. M. Simmons, Jr.Focus of the meeting was the advective flux of water and solute across sediment‐water interfaces. This important linkage between land and surface aquatic environments via groundwater is receiving increasing attention with requirements to identify and predict all impacts of natural and anthropogenic solute inputs to surface waters, even those hidden from view and long neglected. Papers covered a wide range and dealt with such topics as measurements of upward advective flow 20 km offshore in oceanic settings, solute transport into estuarine marshes, geoelectric estimates of groundwater discharge along 300 km of Lake Michigan coastline, field, and lab studies of both reactive and nonreactive solute in groundwater discharge to surface waters, and use of environmental isotopes to trace flow paths and determine residence times of water in catchme
ISSN:0002-8606
DOI:10.1029/EO071i051p01872-01
年代:1990
数据来源: WILEY
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6. |
CRAF science cut; Cassini teams selected |
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Eos, Transactions American Geophysical Union,
Volume 71,
Issue 51,
1990,
Page 1873-1873
Anonymous,
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PDF (1569KB)
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摘要:
In mid‐November the National Aeronautics and Space Administration selected the principal investigators and science teams for the Cassini mission to Saturn and “de‐selected” two instruments on the Comet Rendezvous'Asteroid Flyby (CRAF) mission. The cancellation of the instruments—the penetrator and the scanning electron microscope and particle analyzer—was made to keep the costs of the joint CRAF/Cassini project within the $1.6 billion limit mandated by Congress. CRAF's costs had become a concern earlier this year due in part to increased cost estimates for the penetrator and the spacecraft's radioisotope thermoelectric generators and a decrease in funding for the spacecraft propulsion module, which is being provided by Germany. After a cost review of the program by NASA's Qffice of Space Science and Applications and recommendations by the National Research Council's Space Science Board, NASA decided that both the penetrator and the scanning electron microscope would have to be cut to keep CRAF within
ISSN:0002-8606
DOI:10.1029/EO071i051p01873
年代:1990
数据来源: WILEY
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