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991.
A. E. Gledzer E. B. Gledzer A. A. Khapaev Yu. L. Chernous’ko 《Izvestiya Atmospheric and Oceanic Physics》2014,50(2):122-133
Results of experiments are considered for flows generated by different sources-sinks of mass in the rotating annular channel with beta-effect simulation using the inclined bottom. Diagrams of regimes are presented in parameters of the dimensionless angular velocity of the zonal flow averaged over the channel width and the dimensionless angular velocity of transport of vortex perturbations of cyclonic and anticyclonic types. In experiments and the simplest linear theories, most attention is paid to diagram regions with a slow motion of vortices relative to the rotating coordinate system near the parameters for stationary Rossby waves. 相似文献
992.
M. A. Tolstykh N. A. Diansky A. V. Gusev D. B. Kiktev 《Izvestiya Atmospheric and Oceanic Physics》2014,50(2):111-121
A coupled atmosphere-ocean model intended for the simulation of coupled circulation at time scales up to a season is developed. The semi-Lagrangian atmospheric general circulation model of the Hydrometeorological Centre of Russia, SLAV, is coupled with the sigma model of ocean general circulation developed at the Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), INMOM. Using this coupled model, numerical experiments on ensemble modeling of the atmosphere and ocean circulation for up to 4 months are carried out using real initial data for all seasons of an annual cycle in 1989–2010. Results of these experiments are compared to the results of the SLAV model with the simple evolution of the sea surface temperature. A comparative analysis of seasonally averaged anomalies of atmospheric circulation shows prospects in applying the coupled model for forecasts. It is shown with the example of the El Niño phenomenon of 1997–1998 that the coupled model forecasts the seasonally averaged anomalies for the period of the nonstationary El Niño phase significantly better. 相似文献
993.
P. O. Zavialov P. N. Makkaveev B. V. Konovalov A. A. Osadchiev P. V. Khlebopashev V. V. Pelevin A. B. Grabovskiy A. S. Izhitskiy I. V. Goncharenko D. M. Soloviev A. A. Polukhin 《Oceanology》2014,54(3):265-280
This paper presents the results of long-term in situ and satellite measurements at shelf areas adjacent to the estuaries of the small rivers of the Russian coast of the Black Sea (Mezyb, Pshada, Vulan, Tuapse, Bitkha, Sochi, Cudepsta, Mzymta). The quantitative characteristics of the response of the hydrophysical and hydrochemical fields at the sea shelf on the influence of the continental river discharge are presented for each of these areas. A number of indicators of the water quality (the concentrations of the nitrate and nitrite forms of nitrogen, the phosphorus, the silica, the dissolved oxygen, the value of the total alkalinity and pH, the mineral and organic suspended matter, and the chlorophyll a) are considered in the context of the anthropogenic and terrigenous influence. In this paper, the emphasis was placed on the Mzymta River plume at the shelf area adjacent to the city of Sochi, where the measurements were repeatedly performed during the spring flooding conditions in the period from 2007 until 2012. The interannual variability of the water quality indicators and the seasonal and short-term variability of the area and the configuration of the plume, which transports suspended matter and anthropogenic pollution, were considered. 相似文献
994.
A laser-driven experiment produces images of dense shocked material by x-ray transmission. The post-shock material is sufficiently
dense that no significant signal passes through the dense layer, and therefore the shock compression cannot be directly measured
by comparing transmitted intensities. One could try to determine the shock compression ratio by observing the ratio of the
total distance travelled by the shock to the dense post-shock layer width, but small deviations of the angle of the shock
with respect to the angle of imaging create large asymmetric errors in observation. A statistical approach to recovering shock
compression by appropriately combining data from several experiments is developed, using fits to a simple model for the shock
and shock tube geometry. 相似文献
995.
R. E. Gershberg A. V. Terebizh A. A. Shlyapnikov 《Bulletin of the Crimean Astrophysical Observatory》2011,107(1):11-19
A catalogue of dwarf stars with different manifestations of Solar-type activity is compiled based on publications of the last
10–15 years. The catalogue includes objects with dark spots, hydrogen and calcium chromospheric emission, short-lived flares
in different wavelength ranges, and radio and X-ray emission of stellar corona. The resulting compiled list includes 5535
objects. 相似文献
996.
M. B. Martynov S. N. Alexashkin N. M. Khamidullina O. I. Orlov N. D. Novikova E. A. Deshevaya V. I. Trofimov 《Solar System Research》2011,45(7):593-596
The article presents an analysis of the Phobos-Grunt mission, a classification of its phases in terms of planetary protection,
and the main principles of activities management and definition of actions for fulfilling the planetary-protection requirements
developed by Committee on Space Research. 相似文献
997.
This is an analysis of the dependence of the flare activity of the well known flare star UV Ceti on the linear distance between
the components of this binary system. It is shown that its flaring activity clearly depends on the mutual distance of the
components, while this kind of variability is not seen in isolated flare stars. 相似文献
998.
The twin STEREO spacecraft have been observing the Sun since 2006. Even though STEREO has only been active during solar minimum
conditions so far, an important number of coronal mass ejections (CMEs) and their interplanetary counterparts (ICMEs) have
been observed. Many of the ICMEs can be linked back to the corresponding CMEs on the Sun through the combination of remote-sensing
and in situ observations. This paper aims to answer the question whether a CME observed by a coronagraph will be detected in situ by a spacecraft in a specific location in the heliosphere. We use a flux-rope-like model fit to the STEREO SECCHI/COR2 data
to obtain the direction of CME propagation and its geometrical configuration in three dimensions. Based on model parameters,
we then calculate their angular widths and determine whether they should have been detected by STEREO-A, STEREO-B, Wind or ACE. We compare the results with corresponding in situ observations of ICMEs. We find that predictions of ICME detections on the base of COR2 data generally match well the actual
in situ observations. 相似文献
999.
Radio stars are identified optically with bright stars located in the direction of the cluster A3487 (RA(J) = 11h31m58s, DEC(J) = −31°11’34".8) with an accuracy determined by the refraction of radio waves in the interstellar medium in this direction
of the sky. Within an area of 1 sq. degree, 60% of the strong radio sources with P > 0.004 Jy are identified with stars brighter
than 10 m. 相似文献
1000.
V. R. MARTHI J. N. CHENGALUR Y. GUPTA G. C. DEWANGAN D. BHATTACHARYA 《Journal of Astrophysics and Astronomy》2011,32(4):451-455
We describe the serendipitous discovery of a very steep-spectrum radio point source in low-frequency Giant Metrewave Radio
Telescope (GMRT) images of the supernova remnant (SNR) G76.9+1.0. The steep spectrum, as well as the location of the point
source near the centre of this SNR confirm that this indeed is the pulsar J2022+3842. Archival Chandra X-ray data shows a point source coincident with the radio point source. However, no pulsed radio emission was detected despite
deep searches at 610 MHz and 1160 MHz – which can be understood to be due to temporal broadening of the pulses. Weak pulsed
emission has indeed been seen at 2 GHz with the Green Bank Telescope (GBT), establishing the fact that scattering is responsible
for its non-detection at low radio frequencies. We underline the usefulness of low-frequency radio imaging as a good technique
to prospect for pulsar candidates. 相似文献