Detection of Low-Amplitude Lightning with LINET in Europe
The VLF/LF lightning detection network LINET, newly installed in a large part of Europe (see Betz et al., this conference), was used to investigate low-amplitude strokes of storms occurring in different regions. In Germany and wide areas of adjacent countries the relatively small sensor- baseline of less than 250 km and the treatment of signals irrespective of wave-forms allow particularly efficient identification of such events. As characteristic measure of the detection efficiency we do not use the ‘lower limit’ of reported normalized currents but the peak of the amplitude distributions, According to results from many other networks ? Is reported to lie typically between 15 kA and 30 kA; in some countries, though, commercially operating networks report peak values near the significantly smaller value of 10 kA. A drop of (A) To lower values reflects primarily increasing detection efficiency and a better description of the physical situation. Furthermore, one must take into account that amplitude distributions determined for storm cells depend on the type of storm, time of year and geographical region. While there is excellent agreement among high-amplitude tails from different networks, LINET produces (A)-values much closer to 5 kA than to 10 or 15 kA, a result which needs further investigation. Of practical interest are low-current ground strokes (CG) which are not part of a CG multi-stroke flash but occur isolated in time and space.
K. Schmidt H. D. Betz B. Fuchs V. Meyer P. Laroche P. Blanchet W. P. Oettinger E. Defer
University of Munich, Department of Physics, 85748 Garching, Germany ONERA, 92322 Chatillon, France NowCast mobile Inc., 82266 Stegen, Germany LERMA-Observatoire de Paris, 75014 Paris, France
国际会议
第13届国际大气电学会议(The 13th International Conference on Atmospheric Electricity)
北京
英文
2007-08-13（万方平台首次上网日期，不代表论文的发表时间）