The effect of horizontal resolution on ocean surface heat fluxes in the ECMWF model     

Peter J Gleckler  Karl E Taylor 《Climate Dynamics》1993,9(1):17-32

Annual mean ocean surface heat fluxes have been studied as a function of horizontal resolution in the ECMWF model (cycle 33) and compared with Oberhuber's COADS (1959–1979) based empirical estimates. The model has been run at resolutions of T21, T42, T63 and T106 for 15 months with prescribed monthly varying climatological SST and sea ice. The T42 simulation was extended to 2 years, which enabled us to determine that many differences between the resolution runs were significant and could not be explained by the fact that individual realizations of an ensemble of years can be expected to give different estimates of the annual mean climate state. In addition to systematic differences between the modeled and the observed fluxes, the simulated fields of surface shortwave and longwave radiation showed much more spatial variability than the observed estimates. In the case of the longwave radiation this may be attributable more to deficiencies in the observations than to errors in the model. The modeled latent and sensible heat fields were in better agreement with observations. The primary conclusion concerning the dependence of ocean surface fluxes on resolution is that the T21 simulation differed significantly from the higher resolution runs, especially in the tropics. Although the differences among the three higher resolution simulations were generally small over most of the world ocean, there were local areas with large differences. It appears, therefore, that in relation to ocean surface heat fluxes, a resolution greater than T42 may not be justified for climate model simulations, although the locally large differences found between the higher resolution runs suggest that convergence has not been achieved everywhere even at T106.  相似文献   

The photoelectron spectra of some Tl-Sb sulphosalts     

Ivan Gržetić  Tonći Balić Žunic 《Physics and Chemistry of Minerals》1993,20(4):285-296

The results of X-ray induced photoelectron spectroscopy (XPS) experiments on several phases of the ternary system Tl-Sb-S are reported. The binding energies of the inner S, Sb and Tl electrons increase with increasing quantities of Sb and decreasing amounts of Tl in these compounds. This is explained by the influences of the proportions of the bonded metals on the effective electron affinity of S. The higher proportions of the more electronegative element bonded to S cause the increase of its effective electron affinity. The results for Tl₂S (carlinite), Tl₃SbS₃, TlSbS₂ (weissbergite), TlAsS₂ (lorandite) and Sb₂S₃ (antimonite) can be interpreted in this way. The results for Tl₄S₃ suggest a predominantly covalent character of bonding for both Tl(III) and Tl(I), which are present in this sulfide. From comparison with Tl₃SbS₄ it could be supposed that Tl(III)-S bond has a more covalent character than Sb(V)-S bond. The results for Tl₃SbS₄ are in agreement with crystal structure data and the results of Moessbauer spectroscopy. For AsS (realgar) the binding energies of the inner electrons of As and S significantly increase, showing that the electrons in molecular orbitals are less strongly bonded to individual atoms, as compared to pure elements. The results for the amorphous TlSb₅S₈ (corresponding in composition to parapierrotite) suggest that in amorphous compound the Tl-S bonding is stronger and the coordination of Tl more regular than in a crystalline one.  相似文献   

Reports     

E. Thorsen  K. Segadal  L. E. B. Stuhr  K. Troland  M. Gr?nning  et al. 《GeoJournal》1990,20(2):176-180

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Time scale of hydrothermal water-rock reactions in Yellowstone National Park based on radium isotopes and radon     

Jordan F. Clark  Karl K. Turekian 《Journal of Volcanology and Geothermal Research》1990,40(2)

We have measured ²²⁴Ra (3.4 d), ²²⁸Ra (5.7 yr), and ²²⁶Ra (1620 yr) and chloride in hot spring waters from the Norris-Mammoth Corridor, Yellowstone National Park. Two characteristic cold-water components mix with the primary hydrothermal water: one for the travertine-depositing waters related to the Mammoth Hot Springs and the other for the sinter-depositing Norris Geyser Basin springs. The Mammoth Hot Springs water is a mixture of the primary hydrothermal fluid with meteoric waters flowing through the Madison Limestone, as shown by the systematic decrease of the (²²⁸Ra/²²⁶Ra) activity ratio proceeding northward. The Norris Geyser Basin springs are mixtures of primary hydrothermal water with different amounts of cold meteoric water with no modification of the primary hydrothermal (²²⁸Ra/²²⁶Ra) activity ratio. Using a solution and recoil model for radium isotope supply to the primary hydrothermal water, a mean water-rock reaction time prior to expansion at 350°C and supply to the surface is 540 years assuming that 250 g of water are involved in the release of the radium from one gram of rock. The maximum reaction time allowed by our model is 1150 years.  相似文献   

Planktonic dimethylsulfide and cloud albedo: An estimate of the feedback response     

Jonathan A. Foley  Karl E. Taylor  Steven J. Ghan 《Climatic change》1991,18(1):1-15

Partial control of climate by the biosphere may be possible through a chain of processes that ultimately links marine plankton production of dimethylsulfide (DMS) with changes in cloud albedo (Charlson et al., 1987). Changes in cloud optical properties can have profound impacts on atmospheric radiation transfer and, hence, the surface environment. In this study, we have developed a simple model that incorporates empirically based parameterizations to account for the biological control of cloud droplet concentration in a first attempt to estimate the strength of the DMS-cloud albedo feedback mechanism. We find that the feedback reduces the global climatic response to imposed perturbations in solar insolation by less than 7%. Likewise, it modifies the strength of other feedbacks affecting surface insolation over oceans by roughly the same amount. This suggests that the DMS-cloud albedo mechanism will be unable to substantially reduce climate sensitivity, although these results should be confirmed with less idealized models when more is known about the net production of DMS by the marine biosphere and its relation to aerosol/cloud microphysics and climate.  相似文献   

The coast of Puget Sound: John Downing. University of Washington Press. 1983. 130 pp. ISBN 0-295-95944-4. $8.95     

Karl Banse 《Marine pollution bulletin》1985,16(11):457

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Sr-gorceixite,a weathering product in rich iron ores from the Córrego do Feijão Mine,Minas Gerais,Brazil     

Wania Greiffo  Klaus Herrmann  Georg Müller  Karl W. Strauss 《Contributions to Mineralogy and Petrology》1984,87(4):418-419

A sulfate-bearing Sr-Ba phosphate (Sr-gorceixite) formed by supergene alteration in rich iron ores from Minas Gerais, Brazil, has been studied by means of microprobe techniques. Analytical data and the structural formula are presented.  相似文献   

Gleichzeitigkeit von Nord- und Südföhn bei einer Westlage     

Dr. Karl Frey 《Meteorology and Atmospheric Physics》1986,34(3-4):349-366

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Development and changes in the Eastern Province of Saudi Arabia     

Barth  Hans Karl  Quiel  Friedrich 《GeoJournal》1986,13(3):251-259

Due to a particularly favourable geologic and tectonic setting in the Eastern Province, Saudi Arabia has the world largest oil reserves and is the third largest oil-producing nation in the world. Based on oil and gas revenues, the Kingdom experienced an overwhelming development during the last few decades, changing a desert country into a modern industrialized nation. Main characteristics of spatial changes are based on processes of urbanization and industrialization, on agricultural reclamations and infra-structural developments. Since the natural environment of deserts and semi-deserts in the Eastern Province is determined by an extremely sensitive equilibrium, environmental impacts, shortages in water resources, as well as limited human resources are causing basic problems, which will influence future developments.  相似文献   

New aromatic biomarkers and possible maturity indicators found in New Albany Shale extracts     

Mei-In M. Chou  Karl V. Wood 《Organic Geochemistry》1986,9(6)

Aromatic hydrocarbons from benzene extracts of New Albany Shale were characterized. A biomarker that has a molecular weight of 546 and a structural configuration consistent with that of an alkyl-aromatic hydrocarbon (C₄₀H₆₆) was tentatively identified. It was found that the relative concentrations of the biomarker are indicative of differing levels of thermal maturity of the shale organic matter. A 40-carbon bicyclic carotenoid (C₄₀H₄₈) is proposed as the geochemical precursor of this biomarker. Thermal maturity of the shale organic matter can also be differentiated by observing differences in “fingerprints” as obtained by field-ionization mass spectrometry on the aromatic hydrocarbon fraction. Using this technique, we found that the more mature shale samples from southeastern Illinois contain more low molecular weight extractable aromatic hydrocarbons and the less mature shale samples from northwestern Illinois contain more high molecular weight extractable aromatic hydrocarbons. It was demonstrated that field-ionization and tandem mass spectrometric techniques through fingerprint and individual compound identification, are useful for shale aromatic hydrocarbon fraction characterization and for thermal maturation interpretation.  相似文献