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21.
Arne Lande 《Aquatic Sciences - Research Across Boundaries》1972,34(1):34-40
Summary Trapped sea-water in R?rholtfjorden, Telemark, Norway, was discovered in 1951 by?smund Ystad who was a student at the Department of Limnology, University of Oslo. The lake was investigated continuously from August
1951 to July 1952, and the results are found inYstad [12] andStr?m [8, 9, 10, 11].
On 25 February 1971 some water samples were taken from R?rholtfjorden to supply the information from the lake, and if possible
record changes in the water for the last 20 years. The tables contain chemical data, pH, temperature and oxygen content. The
trapped sea-water is also compared with original sea-water with the same chloride content.
It is difficult to say anything about changes in the salt-water because of uncertainty regarding the depth measurements. But
a so-called semi-stagnation (Str?m [8]) was not observed (Fig. 3). It is possible that about one meter of the trapped sea-water has been lost during the last
20 years because of the removed semi-stagnation.
Zusammenfassung Im R?rholtfjord, Telemark, Norwegen, wurde 1951 von?smund Ystad, Universit?t Oslo, ?gefangenes? Meerwasser entdeckt, welches dann von August 1951 bis Juli 1952 kontinuierlich untersucht wurde. Die Resultate sind beiYstad [12] undStr?m [8, 9, 10, 11] publiziert. Im February 1971 wurden erneut Proben aus dem Fjord genommen, um eventuelle Ver?nderungen w?hrend der vergangenen 20 Jahre festzustellen. Es wurden chemische Daten sowie pH, Temperatur und O2-Gehalt aufgenommen. Das ?gefangene? Wasser wurde auch mit Originalmeerwasser derselben Salinit?t verglichen. Wegen der Ungenauigkeit der Tiefenmessungen ist es schwierig, etwas über Ver?nderungen auszusagen. Indessen wurde eine sog. Semi-Stagnation, wie sieStr?m [8] beschreibt, nicht beobachtet (Fig. 3). M?glicherweise ging etwa 1 m des ?gefangenen? Wassers zufolge des Verschwindens jener Semi-Stagnation verloren.
Résumé De l’eau de mer ?captivée? dans le R?rholtfjord, Telemark, Norvège, fut découverte en 1951 par?smund Ystad, étudiant en Limnologie à l’Université d’Oslo. Des expériences avec l’eau de ce lac ont été poursuivies continuellement d’ao?t 1951 à juillet 1952 et les résultats ont été publiés parYstad [12] etStr?m [8, 9, 10, 11]. Le 25 février 1971, de nouveaux échantillons d’eau ont été prélevés dans le fjord pour étudier si, dans les 20 dernières années, d’éventuels changements étaient survenus. Les tableaux présentés contiennent les données chimiques, ainsi que le pH, la température et le taux d’oxygène. En plus, l’eau ?captivée? est comparée avec l’eau de mer originale, au même taux de salinité. Il est difficile de s’exprimer sur les changements survenus dans l’eau, à cause de l’incertitude concernant les mesures de profondeur. Cependant, on n’a pas observé une dite semi-stagnation comme l’a décriteStróm [8] (fig. 3). Il est possible qu’environ un mètre de cette eau ?captivée? se soit perdue, durant les 20 dernières années, par la disparition de la semi-stagnation.相似文献
22.
Uwe Mikolajewicz Matthias Gröger Ernst Maier-Reimer Guy Schurgers Miren Vizcaíno Arne M. E. Winguth 《Climate Dynamics》2007,28(6):599-633
A new complex earth system model consisting of an atmospheric general circulation model, an ocean general circulation model,
a three-dimensional ice sheet model, a marine biogeochemistry model, and a dynamic vegetation model was used to study the
long-term response to anthropogenic carbon emissions. The prescribed emissions follow estimates of past emissions for the
period 1751–2000 and standard IPCC emission scenarios up to the year 2100. After 2100, an exponential decrease of the emissions
was assumed. For each of the scenarios, a small ensemble of simulations was carried out. The North Atlantic overturning collapsed
in the high emission scenario (A2) simulations. In the low emission scenario (B1), only a temporary weakening of the deep
water formation in the North Atlantic is predicted. The moderate emission scenario (A1B) brings the system close to its bifurcation
point, with three out of five runs leading to a collapsed North Atlantic overturning circulation. The atmospheric moisture
transport predominantly contributes to the collapse of the deep water formation. In the simulations with collapsed deep water
formation in the North Atlantic a substantial cooling over parts of the North Atlantic is simulated. Anthropogenic climate
change substantially reduces the ability of land and ocean to sequester anthropogenic carbon. The simulated effect of a collapse
of the deep water formation in the North Atlantic on the atmospheric CO2 concentration turned out to be relatively small. The volume of the Greenland ice sheet is reduced, but its contribution to
global mean sea level is almost counterbalanced by the growth of the Antarctic ice sheet due to enhanced snowfall. The modifications
of the high latitude freshwater input due to the simulated changes in mass balance of the ice sheet are one order of magnitude
smaller than the changes due to atmospheric moisture transport. After the year 3000, the global mean surface temperature is
predicted to be almost constant due to the compensating effects of decreasing atmospheric CO2 concentrations due to oceanic uptake and delayed response to increasing atmospheric CO2 concentrations before. 相似文献
23.
Inggard Arne Blakar 《Aquatic Sciences - Research Across Boundaries》1978,40(1):191-198
A highly flexible and efficient gravity corer, easy to construct from inexpensive and readily available material, is described. Barrels of various length can be swiftly interchanged according to requirements in the field. Hollow weights can easily be adjusted to the most appropriate height of the barrel. The simple but reliable closing valve (constructed of two plastic funnels) can be adapted to other types of gravity corers as well. Several useful modifications of the corer are discussed. 相似文献
24.
Arne Råheim 《Lithos》1975,8(3):221-236
Ferromagnesian minerals, particularly garnet but also phengite, omphacite and talc, from eclogites and surrounding schists from the Lyell Highway-Collingwood river area, western Tasmania are compositionally zoned.In rocks which have suffered little secondary alteration the Mg-value () of granets increases from core to rim, while the Mg-value of the most important coexisting ferromagnesian phases (clinopyroxene, phengite and talc in different assemblages) decreases from core to rim. CaO decreases from core to rim in garnet. MnO may show little or no variation in garnet, or decrease from core to rim.When compared with experimental data, the zoning of these minerals can be uniquely explained by growth during changing P,T conditions. The eclogites and the surrounding schists have the same prograde P,T history.When determining the KD-values of garnet and its coexisting ferromagnesian phases it is important to consider secondary rim alterations as well as the prograde zoning of the mineral. 相似文献
25.
Inggard Arne Blakar 《Aquatic Sciences - Research Across Boundaries》1980,42(1):78-83
A simple, cheap and easily constructable burette, particularly useful for alkalinity, dissolved oxygen and hardness titration is described. Precise titrant delivery (<1 μl) is controlled by a handy ‘clothespin valve’ connected to the lower opening of appropriately sized graduated pipettes or burette tubes. The burette is small, flexible and easily portable and should be highly recommended as an all round field burette for limnochemists. 相似文献
26.
Experimental data combined with data from natural rocks have been used to calibrate a geothermometer based on the distribution of Fe2+ and Mg between coexisting garnets and phengites. The pressure effect on the K D -value appears to be considerable. The calculated thermometer is expressed as $$T(K) = \frac{{3685 + 77.1P(kb)}}{{InK_D + 3.52}}.$$ The use of this \(K_{D_{(FeO/MgO)} }^{ga + ph}\) geothermometer on eclogites with low Fe2O3 content, gives P-T values which are in good accordance with those obtained by other methods. The problems that arise when Fe3+ is present in larger amounts, are discussed. 相似文献
27.
Arne Olsen 《Contributions to Mineralogy and Petrology》1974,47(2):141-152
Plagioclase feldspars with mean compositions Ab91,3Or4,7An4,0 and Ab88,7An10,1Or1,2 have been studied by transmission electron microscopy and electron diffraction. The substructure consists of thin lamellae of albite and oligoclase. Two types of orientations of the lamellar planes were observed. The orientation of the more common type was found to change from (08 \(\bar 1\) ) to about ( \(\bar 1\) , 21, \(\bar 2\) ) as a function of the mean potassium content. The plane of the other type was found to be near ( \(\bar 7\) 12). Only the first type of lamellae produces visible Schiller colours. 相似文献
28.
Talc-garnet-kyanite-quartz schist occurs in an eclogite-bearing terrane in the Precambrian of Western Tasmania. It is argued that this rock was formed at a pressure of ? 10 kb and a temperature of 600°±20° C. Chemical zoning in the garnet and talc preserves evidence of increasing temperature during growth of the major minerals. 相似文献
29.
Steffi Burmeister Konrad Willner Valentina Schmidt Jürgen Oberst 《Journal of Geodesy》2018,92(9):963-973
A functional model for a bundle block adjustment in the inertial reference frame was developed, implemented and tested. This approach enables the determination of rotation parameters of planetary bodies on the basis of photogrammetric observations. Tests with a self-consistent synthetic data set showed that the implementation converges reliably toward the expected values of the introduced unknown parameters of the adjustment, e.g., spin pole orientation, and that it can cope with typical observational errors in the data. We applied the model to a data set of Phobos using images from the Mars Express and the Viking mission. With Phobos being in a locked rotation, we computed a forced libration amplitude of \(1.14^\circ \pm 0.03^\circ \) together with a control point network of 685 points. 相似文献
30.
Albert M. Fowler K. Michael Merrill William Ball Arne Henden Fred Vrba Craig McCreight 《Experimental Astronomy》2002,14(1):61-68
The Orion program is a project to develop a 2K × 2K infrared focal plane using InSb p-on-n diodes for detectors. It is the
natural follow-up to the successful Aladdin 1K × 1K program started in the early 90's. The work is being done at the Raytheon
Infrared Operations Division (RIO, previously known as the Santa Barbara Research Center) by many of the same people who created
the Aladdin focal plane. The design is very similar to the successful Aladdin design with the addition of reference pixels,
whole array readout (no quadrants), two-adjacent-side buttability, and a packaging design that includes going directly to
the ultimate focal plane size of 4K × 4K. So far we have successfully made a limited number of hybrid modules with InSb detectors.
In this paper we will describe the design features and test data taken from some of these devices.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献