Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science最新文献_第7页

Study of the thermospheric-ionospheric response to intense geomagnetic storms at middle latitudes 中纬度地区热层-电离层对强地磁风暴响应的研究

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00012-5

A. Belehaki , I. Tsagouri

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引用次数: 7

Observations of gravity waves of meteorological origin in the F-Region ionosphere F区电离层中气象成因重力波的观测

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00024-1

J. Boška, P. Šauli

引用次数: 41

Polar OH-airglow temperature variations in the 87/88 winter 87/88年冬季极地OH气辉温度变化

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00021-6

K.P. Nielsen , C.S. Deehr , E. Raustein , Y. Gjessing , F Sigernes

引用次数: 4

Acoustic and ionospheric disturbances from point acoustic source 点声源的声学和电离层扰动

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00027-7

Ya.V. Drobheza , V.M. Krasnov

引用次数: 0

VLF monitorig of atmosphere-ionosphere boundary as a tool to study planetary waves evolution and seismic influence 甚低频大气-电离层边界监测仪作为研究行星波演化和地震影响的工具

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00030-7

O.A. Molchanov , M. Hayakawa

引用次数: 5

Significance of water complexes in the atmosphere 大气中水复合物的意义

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00035-6

J.E. Headrick, V. Vaida

{"title":"Significance of water complexes in the atmosphere","authors":"J.E. Headrick, V. Vaida","doi":"10.1016/S1464-1917(01)00035-6","DOIUrl":"10.1016/S1464-1917(01)00035-6","url":null,"abstract":"<div><p>Using standard statistical and thermodynamic procedures, we calculate equilibrium constants for the formation of select, hydrogen-bonded water complexes, namely the water dimer and the cyclic trimer and tetramer, and use them to estimate the atmospheric abundances of these species. We generate water complex altitude profiles (0–30 km) for both a saturated and an unsaturated atmosphere and discuss the dominant factors influencing our results. In our analysis, particular emphasis is given to the significance that water monomer concentrations, complex binding energies, hydrogen-bond energies, and entropy have on the calculated abundance profiles. We examine the importance of enthalpy and entropy at atmospheric temperatures and show how each contributes to our calculated equilibrium constants. By applying a universal 2 °C temperature increase throughout the troposphere and lower stratosphere, we are able to model the effect that global warming would have on (H<sub>2</sub>O)<sub>n</sub> abundances in a saturated atmosphere. We also illustrate the effect that this thermal variation would have on entropy, enthalpy, and K<sub>p</sub>(T) values. Based on our results, we assess the atmospheric significance of water dimers and cyclic water complexes.</p></div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 7","pages":"Pages 479-486"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)00035-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81981944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

The collision meter: An experimental technique to measure charged-neutral interactions and gas composition in the upper atmosphere 碰撞计:一种测量高层大气中带电-中性相互作用和气体成分的实验技术

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(00)00116-1

J.H. Clemmons , R.F. Pfaff

引用次数: 1

Two-dimensional simulation of two viscous debris flows in Austria 奥地利两次粘性泥石流的二维模拟

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(01)00061-7

J. Hübl, H. Steinwendtner

{"title":"Two-dimensional simulation of two viscous debris flows in Austria","authors":"J. Hübl, H. Steinwendtner","doi":"10.1016/S1464-1917(01)00061-7","DOIUrl":"10.1016/S1464-1917(01)00061-7","url":null,"abstract":"<div><p>Risk mitigation and hazard assessment in steep torrent catchments requires a high level of information about possible runout distances, depth, velocities and resulting impact forces of mass movement processes and its consequences to endangered areas. Two well documented debris flow events at Wartschenbach/Eastern Tyrol and Moschergraben/Styria enable to investigate possible applications of the FLO-2D computer model. The FLO-2D computer model was developed at the Colorado State University and is a grid-based physical process model which routes precipitation-runoff and flood hydrographs over unconfined surfaces and channels using either a kinematic, diffusive or dynamic wave approximation to the momentum equation. All transitions between water floods and fully developed debris flows can be simulated using topographic data files to build the grid elements, information about surface roughness and properties of the sediment water mixture. A quadratic rheological model is used to describe flow behaviour of viscous debris flows. The rheological properties of deposited debris flow material are determined using a rotational viscometer and a new developed conveyor-channel.</p><p>The simulation results and the gained experience are of great promise to the future of debris flow modelling.</p></div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 9","pages":"Pages 639-644"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)00061-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78345721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 37

Auroral particle acceleration processes: the legacy of Hannes Alfvén 极光粒子加速过程:汉内斯·阿尔夫海姆的遗产

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(00)00085-4

R. Lundin

{"title":"Auroral particle acceleration processes: the legacy of Hannes Alfvén","authors":"R. Lundin","doi":"10.1016/S1464-1917(00)00085-4","DOIUrl":"https://doi.org/10.1016/S1464-1917(00)00085-4","url":null,"abstract":"<div><p>Impacting corpuscular radiation was believed to be the main cause for the aurora even before the space age. However, the means by which charged particles become energized, eventually impacting into the upper atmosphere was a matter of controversy - a controversy which died out only very slowly with time. Hannes Alfvén was the lead scientists in the 1950:ies and 1960:ies who dared to challenge the ruling paradigm of space plasma physics - by 1958 suggesting field-aligned electric “discharges” as the cause of the aurora. Field-aligned electric acceleration of charged particles became a matter of debate for nearly three decades with indirect proofs for its existence steadily mounting with time, yet all the time meeting strong objections. In retrospect one may wonder why rebutting was so important. Why clinging to the concept of infinite conductivity along magnetic field lines? The reason was simple, because it challenged a ruling paradigm in space plasma physics, requiring a strong modification of “ideal MHD”.</p><p>The notion of “frozen-in-field-lines”, invented by Hannes Alfvén, is a useful concept in describing large scale morphologies. However, observations from space plasma experiments shows that the condition of frozen-in-field-lines is violated in most interesting regions where plasma acceleration occurs. Alfvén wanted to remedy what he considered the “misuse of MHD” by emphasizing currents instead of magnetic fields in space plasma physics.</p><p>In this paper I will review the energy and momentum coupling originally proposed by Alfvén and their consequences for the acceleration of charged particles. Plasma acceleration processes, well known and recognized from studies of planetary magnetospheres in our solar system, are applicable also for more remote space objects in the Universe - such as stars and galaxies. The many astrophysical implications of his theories is perhaps the most important legacy of Hannes Alfvén. In fact, new evidence for his theories are emerging from contemporary deep space data.</p></div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 1","pages":"Pages 13-23"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(00)00085-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91669475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Comparison of solitary waves and wave packets observed at plasma sheet boundary to results from the auroral zone 等离子体片边界观测到的孤立波和波包与极光带结果的比较

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 DOI: 10.1016/S1464-1917(00)00095-7

C. Cattell , J. Dombeck , A. Keiling , J. Wygant , R. Bergmann , M.K. Hudson , C. Kletzing , F.S. Mozer , M. Temerin , I. Roth , G. Parks

{"title":"Comparison of solitary waves and wave packets observed at plasma sheet boundary to results from the auroral zone","authors":"C. Cattell , J. Dombeck , A. Keiling , J. Wygant , R. Bergmann , M.K. Hudson , C. Kletzing , F.S. Mozer , M. Temerin , I. Roth , G. Parks","doi":"10.1016/S1464-1917(00)00095-7","DOIUrl":"https://doi.org/10.1016/S1464-1917(00)00095-7","url":null,"abstract":"<div><p>The plasma sheet boundary, at distances intermediate between the auroral acceleration region and the regions where energy conversion associated with substorms occurs, is very dynamic with electron and ion beams, field-aligned currents and many types of waves and non-linear structures. We discuss electric and magnetic fields observations of waves occurring at two very different time-scales. At the longer scales (10's of seconds), Wygant (2000) have shown that the observed fields are associated with Alfvenic fluctuations which have their largest electric field normal to the average plane of the plasma sheet (δE<sub>N</sub>). The simultaneously observed magnetic field perturbations are azimuthal(δB<sub>T</sub>), resulting in a Poynting flux along the geomagnetic field. The observations are consistent with an incompressible, transverse electromagnetic surface shear Alfven mode at the surface of the plasma sheet boundary. The local δE<sub>N</sub>/δB<sub>T</sub> is consistent with V<sub>A</sub>. The waves provide an intense earthward Poynting flux sufficient to provide the energy necessary for the energization of auroral electron beams. In addition, the large amplitude surface waves are magnetically conjugate (to within 1 degree) to intense auroral emission as determined from the UVI imager, whereas weak aurora are correlated with small amplitude electric fields. Particle detectors simultaneously observe ions flowing up the field line away from the earth, providing further evidence that low altitude acceleration is occurring on conjugate magnetic field lines. At small scales, large amplitude solitary waves are frequently observed, and ion acoustic, lower hybrid, and Langmuir wave packets are sometimes seen. There are clear differences between the solitary wave observations at the plasma sheet boundary and in the low altitude auroral zone. At high altitudes, only electron mode solitary waves have been identified and they occur both in regions of upward and downward field-aligned current, in contrast to the auroral zone where ion solitary waves occur in upward currents and electron solitary waves occur primarily in downward currents. This difference may because the growth of ion acoustic solitons requires that the plasma be strongly magnetized (f<sub>ce</sub>/f<sub>pe</sub> >>1) which is not the case for the observed high altitude plasma sheet boundary crossings. The high altitude events are associated with a wide variety of electron distribution types, whereas the low altitude events occur in regions of flat-top electron beam distributions. Preliminary evidence suggests that the high altitude events may be BGK electron holes, as has been shown for the low altitude events. For the parameter regime usually observed at high attitudes, electron holes would be stable. In addition, initial work on electron acoustic solitons suggests that these compressive waves would occur only for a limited range of parameters, so they are unlikely to explain t","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 1","pages":"Pages 97-106"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(00)00095-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91669911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10