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EXPERIMENTAL STUDY ON REMOTE SENSING OF ATMOSPHERIC SOUNDING BY MEANS OF MULTIFREQUENCY MICROWAVE RADIOMETERS

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Science China Chemistry 1985年第5期28卷 527-536页

作者：赵柏林尹宏杜金林李慧心胡成达朱元竞王义举施庶民江廷久 Peking University department of geophysics Dahua Factory Beijing

In this paper, the principle and method of microwave remote sensing atmospheric sounding are described. In order to carry out the experimental study, the 4 channels in 5mm—1.35 cm band microwave radiometers have been constructed. The field experiment in September-October 1981 was carried out. In this paper, the results obtained by different inversion methods are compared with each other. The experimental result shows that it will be satisfactory, if the temperature profile and inversion of lower atmosphere are derived from remote sensing of 2 channels (frequencies: 52.8 Gc and 54.4. Gc) in 5 mm band. The atmospheric humidity can be obtained from the remote sensing of 1.35 cm band. While the change of air mass exists, signal reveals itself significantly in the atmospheric microwave radiation. The variations of atmospheric temperature and humidity have been analysed and compared with those obtained from radiosonde.

关键词： EXPERIMENTAL STUDY ON REMOTE SENSING OF ATMOSPHERIC SOUNDING BY MEANS OF MULTIFREQUENCY MICROWAVE RADIOMETERS

ANALYTICAL SOLUTIONS OF DOWNSLOPE MOTIONS

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Acta meteorologica Sinica 1991年第1期5卷 71-78页

作者：桑建国 department of geophysics Peking UniversityBeijing

The solutions of downslope motions over a sloping terrain are solved analytically in terms of the atmos- pheric wave equations with a two-layer *** physical meanings of the solutions are *** the lower layer of the atmosphere is stable and deep with strong wind the solution represents strong downslope wind,while as the lower layer is strong stable with light wind the drainage flow is *** dependence of the strength of downslope motion on the atmospheric stratification,wind field structure as well as Scorer parameter is also examined.

关键词： downslope motion atmospheric waves leeside wind drainage flow

The bounding-surfaces record of a barrier spit from Huangqihai Lake,North China:implications for coastal barrier boundary hierarchy

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Chinese Journal of Oceanology and Limnology 2016年第5期34卷 1097-1105页

作者：单新于兴河 Peter D.CLIFT 王天意谭程鹏金丽娜 School of Energy Resources China University of Geosciences(Beijing) department of Geology and geophysics Louisiana State University School of geophysics and Geoinformation Technology China University of Geosciences(Beijing)

Ground-penetrating radar and trenching studies of a barrier spit on the north shore of Huangqihai Lake were made,that reveal important implications for the coastal washover barrier boundary hierarchy and interpretations of this depositional record.A four-fold hierarchy bounding-surface model,representing different levels of impact and genesis,is *** level of the hierarchy is enclosed by a distinct kind of surface characterized by different ground-penetrating radar reflection features,sedimentary characteristics(color,grain size,sorting,rounding and sedimentary structures) and *** suggest that this hierarchical model can be applied to any coastal washover barrier deposits.

关键词： coastal barrier boundary hierarchy washover deposits ground-penetrating radar bounding surface Huangqihai Lake

ON THE SENSITIVE DYNAMICAL SYSTEM AND THE TRANSITION FROM THE APPARENTLY DETERMINISTIC PROCESS TO THE COMPLETELY RANDOM PROCESS

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applied Mathematics and Mechanics(English Edition) 1985年第3期6卷 193-211页

作者：岳曾先张彬 Beijing Peking University department of geophysics

The detailed analysis of the dynamical process of coin tossing is ***,it is illustrated how and why the result is extremely sensitive to the *** is also shown that,as the initial height of the mass center of the coin increase,the final configuration,i.e."head" or "tail",becomes more and more sensitive to the initialparameters(the initial velocity angular velocity,and the initial orientation),the coefficientof the air drag,and the energy absorption factor of the surface on which the coin *** keep the"head" upward initially but allow a small range for the change of some otherinitial parameters,the frequency that the final configuration is"head",would be I if theinitial height h of the mass center is sufficiently small,and would be close to 1/2 if h issufficiently *** interesting question is how this frequency changes continuously fromI to 1/2 as h *** calculations show that such a"transition"is very similarto the transition from laminar to

关键词： ON THE SENSITIVE DYNAMICAL SYSTEM AND THE TRANSITION FROM THE APPARENTLY DETERMINISTIC PROCESS TO THE COMPLETELY RANDOM PROCESS

STUDY ON RADAR-RADIOMETER SYSTEM AND ITS RAINFALL OBSERVATION

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Acta meteorologica Sinica 1991年第3期5卷 307-316页

作者：赵柏林周晓京杜金林 department of geophysics Peking UniversityBeijing

In order to improve the accuracy of the rainfall measurement, a radar-radiometer system has been devel- oped. It could be used to measure the distribution of the rainfall intensity aLld the variation of area rainfall. In field experiment, the accuracy of the rainfall measurement was imporved. In this paper, the error of rainfall measurement by radar will be evaluated and the methods to improve the accuracy of the rainfall measurement will be discussed.

关键词： radar-radiometer system area rainfall rainfall measurement raindrop spectrum rain water content

On the generation of deep focus earthquakes in subduction zones

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Acta Seismologica Sinica(English Edition) 1999年第5期12卷 573-583页

作者：宁杰远臧绍先 department of geophysics Peking University Beijing 100871 China

Following a quasi-dynamic scheme proposed by Minear and Toksoz (1970), thermal structures of subduction zonesfor different models by finite element method (FEM) were calculated. Density distribution and p-wave anomaly ofsubduction zones were calculated at the same time. Comparing with seismological evidences and results of laboratories. it is proposed that earthquakes occurred below 400 km depth are probably controlled by anti-crackmechanism.

关键词： subduction zone numerical simulation phase transformation generation of earthquakes anticrack theory

AN INVESTIGATION OF THE PROBLEM OF OCCURRENCE OF THE ATMOSPHERIC TURBULENCE

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Science in China,Ser.B 1988年第6期31卷 760-768页

作者：郑祖光刘式达张宏剑 Peking Institute of Meteorology department of geophysics Peking University

Using the truncated-spectrum model of Burger’s-Chao Jiping equation, in which thetemperature advection is involved, we investigated the role of three parameters （Ri number, Renumber, Pr number） in occurrence of turbulence. It is shown that the turbulence may oc-cur only in the case of Ri2π2. If Pr is too small （Pr = 0.7 for the atmos-phere）, then the turbulence may occur only in the case of introducing interaction betweenbasic field and perturbation field or adding 'viscosity' to the model. It is emphasized thatthe temperature advection plays an important role in turbulence occurrence. On the parame-ter plane （Ri, Re）, the atmospheric motion states can be divided into the O-region （basicstate）, the P-region （periodic state）, the T-region （chaotic state）, and the T-P region （cha-otic-periodic transition state）. In fact, this is appropriate. Finally, the physical reason of turbu-lence occurrence is discussed.

关键词： line AN INVESTIGATION OF THE PROBLEM OF OCCURRENCE OF THE ATMOSPHERIC TURBULENCE

No apparent lock-in depth of the Laschamp geomagnetic excursion: Evidence from the Malan loess

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Science China Earth Sciences 2006年第9期49卷 960-967页

作者： ZHU Rixiang1, LIU Qingsong1,2, PAN Yongxin1, DENG Chenglong1, ZHANG Rui1 & WANG Xianfeng3 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution), Institute of Geology and geophysics, Chi- nese Academy of Sciences, Beijing 100029, China 2. Institute of geophysics and Planetary geophysics, University of California, Santa Cruz, CA 95064, USA 3. department of Geology and geophysics, University of Minnesota, Minneapolis, MN 55455, USA 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. Institute of geophysics and Planetary geophysics University of California Santa Cruz CA 95064 USA 3. department of Geology and geophysics University of Minnesota Minneapolis MN 55455 USA

The first-order chronological framework of the long-term Chinese loess/paleosol sequences was based mainly on magnetostratigraphy. However, there remain arguments on the lock-in ages of the major geomagnetic reversals. This study systematically compared the stratigraphic locations of the Laschamp excursion and Henrich events (H4 at～39 ka and H5 at～48 ka) recorded by the Luochuan loess profile in the central Chinese Loess Plateau. Results show that the Lascchamp excursion is bracketed well by these two cold events, and the corresponding estimated age is between about 41.7-43.7 ka, which is close to the widely accepted age of ～40-41 ka for the ***, our new results do not suggest apparent lock-in effects in the last glacial Malan loess.

关键词： Chinese loess, Laschamp excursion, Henrich event, lock-in depth.

Full-3D, Full-Wave Seismic Tomography for Crustal Structure in Southern California, USA

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地质学报 2013年第S1期 25-27页

作者： CHEN Po department of Geology and geophysics University of Wyoming

Southern California is one region where the seismic hazard is high and the subsurface geological structure is complex. Three-dimensional structural heterogeneities, in particular, thick sedimentary basins,can have significant influence on the ground motion generated by disastrous earthquakes. To better quantify seismic hazards in Southern California, we need to improve our three-dimensional seismic structure model of the subsurface.

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