The Critical Richardson Number and Limits of Applicability of Local Similarity Theory in the Stable Boundary Layer   总被引：7，自引：7，他引：0  

Andrey A. Grachev  Edgar L Andreas  Christopher W. Fairall  Peter S. Guest  P. Ola G. Persson 《Boundary-Layer Meteorology》2013,147(1):51-82

Measurements of atmospheric turbulence made over the Arctic pack ice during the Surface Heat Budget of the Arctic Ocean experiment (SHEBA) are used to determine the limits of applicability of Monin–Obukhov similarity theory (in the local scaling formulation) in the stable atmospheric boundary layer. Based on the spectral analysis of wind velocity and air temperature fluctuations, it is shown that, when both the gradient Richardson number, Ri, and the flux Richardson number, Rf, exceed a ‘critical value’ of about 0.20–0.25, the inertial subrange associated with the Richardson–Kolmogorov cascade dies out and vertical turbulent fluxes become small. Some small-scale turbulence survives even in this supercritical regime, but this is non-Kolmogorov turbulence, and it decays rapidly with further increasing stability. Similarity theory is based on the turbulent fluxes in the high-frequency part of the spectra that are associated with energy-containing/flux-carrying eddies. Spectral densities in this high-frequency band diminish as the Richardson–Kolmogorov energy cascade weakens; therefore, the applicability of local Monin–Obukhov similarity theory in stable conditions is limited by the inequalities Ri < Ri _cr and Rf < Rf _cr. However, it is found that Rf _cr  =  0.20–0.25 is a primary threshold for applicability. Applying this prerequisite shows that the data follow classical Monin–Obukhov local z-less predictions after the irrelevant cases (turbulence without the Richardson–Kolmogorov cascade) have been filtered out.  相似文献   

Systematic Errors of High–Precision Photometric Catalogues     

Aleksey Mironov  Andrey Zakharov 《Astrophysics and Space Science》2002,280(1-2):71-76

A very accurate imitation of Hipparcos and Tycho Hp, B _T, andV _T magnitudes was made using W, B, V, R magnitudes from the Tien Shan photometric catalogue. The calculated magnitudes were compared to the observed ones. It is shown that there are systematic differences between calculated and observed magnitudes. The systematic errors are supposed to be bound up with the sky scanning procedure on the Hipparcos satellite. Polynomials in powers of coordinates have been proposed to take into account the systematic errors. 6558 stars have been found to be appropriate high-precision photometric standards. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Intergranular diamonds derived from partial melting of crustal rocks at ultrahigh-pressure metamorphic conditions     

Andrey V. Korsakov  Karel Theunissen  Larissa V. Smirnova 《地学学报》2004,16(3):146-151

By reporting for the first time intergranular diamond in quartz–feldspar (Qtz–Kfs) aggregates, the processes of metamorphic diamond formation have to be reconsidered. Based on their Kfs/Qtz ratio, the texture of these aggregates are proposed to result from ‘granitic’ melt with a calculated composition that corresponds well with that of experimental data for the pelitic system. Taking into account experiments on CO₂ solubility in silicate melt under ultrahigh‐pressure conditions, a granitic melt is further suggested to act as a crystallization medium as well as a transport medium for producing metamorphic diamond.  相似文献   

Southern East Siberia Pliocene–Quaternary faults: Database, analysis and inference     

Oksana V. Lunina  ;Riccardo Caputo  ;Anton A. Gladkov  ;Andrey S. Gladkovt 《地学前缘(英文版)》2014,5(4):605-619

This paper presents the first release of an Informational System（IS）devoted to the systematic collection of all available data relating to Pliocene-Quaternary faults in southern East Siberia,their critical analysis and their seismotectonic parameterization.The final goal of this project is to form a new base for improving the assessment of seismic hazard and other natural processes associated with crustal deformation.The presented IS has been exploited to create a relational database of active and conditionally active faults in southern East Siberia（between 100°-114° E and 50°-57° N）whose central sector is characterized by the highly seismic Baikal rift zone.The information within the database for each fault segment is organized as distinct but intercorrelated sections（tables,texts and pictures,etc.）and can be easily visualized as HTML pages in offline browsing.The preliminary version of the database distributed free on disk already highlights the general fault pattern showing that the Holocene and historical activity is quite uniform and dominated by NE-SW and nearly E-W trending faults;the former with a prevailing dip-slip normal kinematics,while the latter structures are left-lateral strike-slip and oblique-slip（with different proportion of left-lateral and normal fault slip components）.These faults are mainly concentrated along the borders of the rift basins and are the main sources of moderate-to-strong（M≥5.5）earthquakes on the southern sectors of East Siberia in recent times.As a whole,based on analyzing the diverse fault kinematics and their variable spatial distribution with respect to the overall pattern of the tectonic structures formed and/or activated during the late Pliocene-Quaternary,we conclude they were generated under a regional stress field mainly characterized by a relatively uniform NW-SE tension,but strongly influenced by the irregular hard boundary of the old Siberian craton.The obtained inferences are in an agreement with the existing models of the development of  相似文献   

Geochemical signal of seasonality in annually laminated organic- carbonate sediments in Shira lake(Khakasia)     

Ivan KALUGIN  Andrey DARIN  Denis ROGOZIN  Gennady TRET’YAKOV 《《地质学报》英文版》2014,88(Z1):12-13

正1 Introduction The most valuable for the task of climate reconstruction are the time series with an annual resolution,which allows to reveal natural periodicity and pass to the search for mechanisms of regional and global climatic changes.Bottom sediments of lakes are one of the best climate archives in addition to tree ring series,ice cores etc.  相似文献   

From Big to Little Rip in modified F(R,G) gravity     

Andrey N. Makarenko  Valery V. Obukhov  Iliy V. Kirnos 《Astrophysics and Space Science》2013,343(1):481-488

We discuss the cosmological reconstruction in modified Gauss-Bonnet (GB) gravity. It is demonstrated that the modified GB gravity may describe the most interesting features of late-time cosmology. We derive explicit form of effective phantom cosmological models ending by the finite-time future singularity (Big Rip) and without singularities in the future (Little Rip).  相似文献   

SphinX: The Solar Photometer in X-Rays     

Szymon Gburek  Janusz Sylwester  Miroslaw Kowalinski  Jaroslaw Bakala  Zbigniew Kordylewski  Piotr Podgorski  Stefan Plocieniak  Marek Siarkowski  Barbara Sylwester  Witold Trzebinski  Sergey V. Kuzin  Andrey A. Pertsov  Yurij D. Kotov  Frantisek Farnik  Fabio Reale  Kenneth J. H. Phillips 《Solar physics》2013,283(2):631-649

Solar Photometer in X-rays (SphinX) was a spectrophotometer developed to observe the Sun in soft X-rays. The instrument observed in the energy range ≈?1?–?15 keV with resolution ≈?0.4 keV. SphinX was flown on the Russian CORONAS–PHOTON satellite placed inside the TESIS EUV and X telescope assembly. The spacecraft launch took place on 30 January 2009 at 13:30 UT at the Plesetsk Cosmodrome in Russia. The SphinX experiment mission began a couple of weeks later on 20 February 2009 when the first telemetry dumps were received. The mission ended nine months later on 29 November 2009 when data transmission was terminated. SphinX provided an excellent set of observations during very low solar activity. This was indeed the period in which solar activity dropped to the lowest level observed in X-rays ever. The SphinX instrument design, construction, and operation principle are described. Information on SphinX data repositories, dissemination methods, format, and calibration is given together with general recommendations for data users. Scientific research areas in which SphinX data find application are reviewed.  相似文献   

History of the Cartography and Toponymy of the Valley of Geysers (Kronotsky Reserve,Kamchatka Peninsula,Russia): From Field Drawings to 3D Documents     

Andrey V. Leonov 《The Cartographic journal》2013,50(3):235-255

The article describes the evolution of the cartography and toponymy of the second largest geyser field in the world – the Valley of Geysers in the Kronotsky Reserve (Kamchatka Peninsula, Russia), discovered in 1941. The toponymy evolved in close connection with the development of the cartographic base that passed through the three stages from the first manual drawings to large-scale maps and to 3D models of the territory. The number of geysers with personal names increased gradually from twelve to more than one hundred. The article presents examples of diagrams and maps as well as tables of thermal features with coordinates. All main sources of literature were analysed for the period of 1941–2017, and the article presents a comprehensive historiography on the investigated topic. The evolution of instruments for the measurement of geyser activity is also briefly overviewed with examples of data obtained using the different methods.  相似文献   

Deposition of 1.88-billion-year-old Iron Formations as a Consequence of Rapid Crustal Growth     

Birger Rasmussen  Ian R. Fletcher  Andrey Bekker  Janet R. Muhling  Courtney J. Gregory  Alan M. Thorne 《Journal of the Geological Society of India》2012,80(1):147

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A new climatology of the Okhotsk Sea derived from the FERHRI database     

Hiroki Uehara  Andrey A. Kruts  Yuriy N. Volkov  Tomohiro Nakamura  Tsuneo Ono  Humio Mitsudera 《Journal of Oceanography》2012,68(6):869-886

This paper introduces a new hydrographic climatology of the Okhotsk Sea; this climatology was constructed from the Far Eastern Regional Hydrometeorological Research Institute (FERHRI) database. The FERHRI database has a volume of data three to five times larger than the data used in previous studies because unpublished Russian observation data have been included in the FERHRI database. After removing erroneous data from the database by pertinent quality control methods, the climatology for 1/4°?×?1/4° grids is produced by applying objective analysis procedures. Features similar to those in previous studies are seen in the intermediate layers in the Okhotsk Sea, whereas our climatology provides values that fill in gaps in previous climatologies. It is obvious from the monthly climatologies that temperature and salinity distributions evolve in accordance with seasonal variations in the Eastern Sakhalin Current and inflow from the North Pacific. We also reconstructed climatologies for the winter mixed layer and dense shelf water from data obtained from the temperature minimum waters identified as the remnants of these two layers. Free access to the 1°?×?1° versions of all climatologies constructed in this study is available through the website.  相似文献