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991.
Formulas for the evaluation of temperature and humidity of air, wind speed, and sensible and latent heat fluxes on the ocean
surface according to the satellite data on the sea-surface temperature and cloudiness are deduced on the basis of the analysis
of many-year radiosonde, meteorological, shipborne, and satellite data. The proposed formulas can also be used for the interpretation
of the results of remote sensing of the ocean and atmosphere by radiometers in the visible, infrared, and microwave regions.
The transformations of radiation and sensible and latent heat fluxes are described depending on the sea-surface temperature
for various cloudiness conditions. The computed values of the amount of water in the atmosphere agree with the radiosonde
data obtained throughout the Earth, including the data of research vessels and stationary weather ships, as well as the data
obtained in the ATEP test ranges and in the Arctic.
__________
Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 56–70, March–April, 2007. 相似文献
992.
V. V. Knysh S. G. Demyshev G. K. Korotaev A. S. Sarkisyan 《Izvestiya Atmospheric and Oceanic Physics》2007,43(3):363-377
A method for combined assimilation of climatic hydrologic fields of temperature, salinity, and the climatic dynamic level of the Black Sea into a model of sea dynamics is proposed. The monthly mean fields of the dynamic sea level were obtained from the results of assimilation of satellite altimetry data into the model. The statistical characteristics of errors in the forecasts of the level, salinity, and temperature were assumed to be proportional to the statistical characteristics of the differences between monthly mean climatic fields of temperature, salinity, and sea level calculated by means of assimilating altimetry observations of the sea level and analogous climatic hydrologic fields. The climatic fields of currents are reconstructed and analyzed. The assimilation of the climatic altimetry level allows the reproduction (in current fields) of quasi-stationary synoptic anticyclonic eddies located along the periphery of the Black Sea Rim Current. 相似文献
993.
994.
Joana F.M.F. Cardoso Denis Langlet Jos F. Loff Ana R. Martins Johannes IJ. Witte Paulo T. Santos Henk W. van der Veer 《Journal of Sea Research》2007,57(4):303-315
The Pacific oyster Crassostrea gigas was introduced in Europe for commercial purposes in the mid 1960s. It was initially thought that low winter temperatures would restrain this species' reproduction and settlement; however, its present distribution in areas where no introduction has taken place suggests that natural invasion and expansion has occurred. Along the European coast, wild populations of Pacific oysters are already found from northern Germany to southern Portugal. Whether C. gigas will continue to further expand through northern waters will depend on its physiological performance. In this study, the performance of wild oyster populations has been studied in terms of growth and reproduction at three stations: La Rochelle (France; 46°N), Yerseke (Oosterschelde estuary, The Netherlands, 51°N), and Texel (Wadden Sea estuary, The Netherlands, 53°N). The French population had the lowest somatic-shell mass ratio and an increase in maximum shell length, somatic and gonadal mass was observed from France to the Netherlands. In addition, mean oocyte diameter decreased significantly from south to north. The combination of increasing gonadal mass and decreasing oocyte volume suggests an increasing reproductive output in terms of egg numbers from France to The Netherlands. Differences in temperature between locations will at least be partly responsible for the observed patterns; however, other environmental factors (such as food availability, predation pressure, sediment type and/or seston concentration) cannot be excluded. Since smaller eggs (oocytes) are thought to have a longer development time, the environmental conditions along the Dutch coast may result in increased larval dispersal and possibly in further population expansion. 相似文献
995.
996.
E. A. Agafonov N. A. Sorokina Yu. A. Prokhorenko E. E. Pavlova 《Physical Oceanography》1995,6(5):395-397
This paper discussesin situ observational data on the directed light attenuation index in the near-surface layer, collected in September 1987. The absolute light attenuation index has been evaluated for a near-shore strip of water 10–15 miles in width. When multidisciplinary research is conducted in the open sea, this part of the sea surface remains unstudied, as the observational grid for it is made larger than the spatial-temporal parameters of the biophysical processes producing optical inhomogeneities.Translated by Vladimir A. Puchkin. 相似文献
997.
J. -M. Auzende L. Géli H. Ondréas J. -Y. Collot Y. Lafoy J. -P. Eissen E. Gracia M. B. Larue C. Olisukulu D. Tolia N. Biliki 《Geo-Marine Letters》1994,14(4):232-237
During the SOPACMAPS 2 crusie carried out by IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer) and ORSTOM (Institut Français de Recherche Scientifique pour le dévelopement en Coopération) on theR/V L'Atalante, in the Central Solomon Arc area, multibeam bathymetric and imagery data and single-channel seismic reflection profiles were collected from an area of about 3500 km2, to evaluate regional tectonics. Structural data geophysical profiles interpretation provide evidence for left-lateral transtensional tectonics on the southern edge of the Central Solomon Trough. This transtensional deformation is represented by faulting, block tilting, and rhombohedral deformation. The regional geology and the analysis of the sedimentary cover allow us to demonstrate that this tectonic occurred in two different phases during Oligocene to Miocene and Pliocene to Pleistocene times. 相似文献
998.
Seasonal and interannual variability of the pressure field and indices of the North Atlantic atmosphere zonal circulation are analysed using historical (1894–1988) observations. It is shown that fluctuations of the index of North Atlantic oscillations (NAO) and that of the eastward transport give evidence of the interannual fluctuations with the typical time scale being 2–7 years. It is shown that the magnitude of interannual NAO index variability exceeds the typical magnitude of seasonal variations, particularly in winter. The time scale of NAO index variations and eastward transport coincides with the typicalEl Niño-southern oscillations (ENSO) temporal scale. The amplitudes of the annual, semi-annual harmonics, and high-frequency fluctuations of the NAO index increase during a typical ENSO event at least by a factor of 2.Translated by V. Puchkin. 相似文献
999.
Accelerated relative sea-level rise and rapid coastal erosion:: testing a causal relationship for the Louisiana barrier islands 总被引:1,自引:0,他引:1
Jeffrey H. List Asbury H. Sallenger Jr. Mark E. Hansen Bruce E. Jaffe 《Marine Geology》1997,140(3-4):347-365
The role of relative sea-level rise as a cause for the rapid erosion of Louisiana's barrier island coast is investigated through a numerical implementation of a modified Bruun rule that accounts for the low percentage of sand-sized sediment in the eroding Louisiana shoreface. Shore-normal profiles from 150 km of coastline west of the Mississippi delta are derived from bathymetric surveys conducted during the 1880s, 1930s and 1980s. An RMS difference criterion is employed to test whether an equilibrium profile form is maintained between survey years. Only about half the studied profiles meet the equilibrium criterion; this represents a significant limitation on the potential applicability of the Bruun rule. The profiles meeting the equilibrium criterion, along with measured rates of relative sea-level rise, are used to hindcast shoreline retreat rates at 37 locations within the study area. Modeled and observed shoreline retreat rates show no significant correlation. Thus, in terms of the Bruun approach, relative sea-level rise has no power for hindcasting (and presumably forecasting) rates of coastal erosion for the Louisiana barrier islands. 相似文献
1000.
An instrumented tetrapod was deployed for three weeks on the Dry Tortugas Bank at a depth of 26 m in February 1995. Bottom
roughness was dominated by shrimp burrows and worm mounds with rms roughness amplitudes ranging from 0.47 to 1.75 cm. Logarithmic
velocity profiles show apparent total roughness heights ranging from 0.30 to 1.45 cm, values consistent with observed biological
roughness. The bed sediments were weakly bound by an algal crust at the sediment–water interface. When this bound layer was
scraped away by a mooring that was accidentally dragged, sharp-crested wave-induced ripples appeared within the resulting
swath. We conclude that physically induced roughness is biologically suppressed, but if dominant, would be significantly higher
than the prevailing biological roughness. 相似文献