The importance of conductivity gradients in ground-based field-aligned current studies |
| |
| Institution: | 1. Max Planck Institut für Aeronomie, 37191 Katlenburg-Lindau, Germany;2. Now at Dept. Communication Systems, LA1 4YR Lancaster University, UK;3. Space Physics Research Institute, Univ. of Natal, 4041 Durban, South Africa;4. Finnish Meteorological Institute, SF-00101 Helsinki, Finland;1. Polymer Research Laboratory, Department of Chemistry, Faculty of Science, University of Maragheh, P.O. Box 55181-83111, Maragheh, Iran;2. Department of Polymer Engineering, Faculty of Engineering, University of Maragheh, P.O. Box 55181-83111, Maragheh, Iran;1. Key Laboratory of Resources Green Conversion and Utilization of State Ethnic Affairs Commission & Ministry of Education, School of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan 430074, China;2. State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu 610065, China;3. Department of Industrial and Systems Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China;4. Hubei Engineering Technology Research Centre for Energy Polymer Materials, South-Central University for Nationalities, Wuhan 430074, China;1. Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology & Science Park, Mahenwatte, Pitipana, Homagama 10206, Sri Lanka;2. Department of Chemistry, Faculty of Science, University of Colombo, Colombo 00300, Sri Lanka;1. Department of Physics, SJC Institute of Technology, Chickballapur, India;2. Department of Physics, Raja Rajeshwari College of Engineering, Bangalore, India;3. Education Technology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India;1. Ningbo Key Lab of Polymer Materials, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang Province, 315201, PR China;2. Faculty of Science and Engineering, University of Nottingham Ningbo China, 199 Taikang East Road, Ningbo, 315000, China;3. University of Chinese Academy of Sciences, Beijing, 100049, PR China;1. Faculty of Chemistry, Biological and Chemical Research Center, University of Warsaw, 101 Żwirki i Wigury Av., PL, 02-089, Warsaw, Poland;2. Institute of Paleobiology, Polish Academy of Sciences, 51/55 Twarda St, PL, 00-818 Warsaw, Poland |
| |
| Abstract: | Magnetosphere-ionosphere coupling is achieved primarily through magnetic field-aligned currents. Such currents are difficult to measure directly and are usually inferred from satellite magnetometer recordings or from ground-based measurements of the divergence of ionospheric electric fields. The latter technique requires a knowledge of the ionospheric conductance distribution. Although it is possible to obtain the ionospheric electric field distribution over large spatial areas with good temporal resolution from coherent backscatter radars, these instruments cannot measure conductivity. Since the equation for computing field-aligned currents explicitly requires the gradient in conductance to be known, the use of statistically averaged models is excluded for case studies. If a dense enough array of magnetometers is available, these data may be used in combination with radar data to produce a measured conductance distribution within the overlapping fields of view. This has been done for data obtained in northern Scandinavia. Comparing field-aligned currents, computed with and without knowing the ionospheric conductance distribution, shows that gradients in conductance can not be ignored, even for quiet geomagnetic conditions. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
