Submitted by Martin Füllekrug. Received: 2000-05-03
Group A) * The discussion on the aerosol hypothesis suggested by Kundt has led to two main ideas: 1) Identify the missing global circuit elements a) above the thundercloud - The first element has been measured by Gish & Wait, JGR, 1950, but the authors indicate a mean storm current of only 0.5 A. It may be of interest to reconsider these technically difficult measurements with the help of an european expert in the field: Rejean Grard at ESA: rgrardestecesanl b) return currents within the Earth. - The return currents within the Earth have never been considered and may be a measurable quantity. A global circuit modeller in Cambridge, Rob Tyler, has shown interest in this regard: rtylerifmuni-kielde 2) Support the aerosol hypothesis with actual measurements. - The split-hemisphere method has been suggested to measure the total current in the atmosphere (see Byrne et al., JGR, 1993) but balloon-borne measurements at higher altitudes still seem to be unsuccessfull (see Byrne et al., JATP, 1991). These measurements may be able to distinguish between field driven ionic currents and the negative aerosols. A german expert who is working with falling spheres has been suggested in this context: Franz-Josef Luebken at luebkenphysikuni-bonnde Group B) * The discussion on sprite occurrences and measurements in Europe has been extremely vivid: - On the AGU meeting, Mike Taylor reported from a flight across Europe (to observe the leonid meteor showers) where he observed european sprites. - Torsten Neubert has lend equipment (cameras) from Steven Mende to actually observe sprites in Europe: neubertdmidk Eventually, the first european sprite campaign will take place in August 2000 in the french Pyrenees, supported by Elizabeth Blanc blancdasebruyeresceafr - Pierre Laroche has committed himself to dig out climatological information on nocturnal positive lightning occurrences in southern France which may be associated with sprites: laroche@onerafr - Colin Price announced the possibility (first target of opportunity) of space shuttle based sprite observations by an israelien astronaut during the spring of 2001. Reference measurements are warmly welcome: cpriceflashtauacil General comments) * Since the ESF network deals with the connection between Space Weather and the Earth weather, it has been suggested to include atmospheric chemists in the field. Rolf Mueller has been suggested in this context: ro.mueller@fz-juelich.de to perform theoretical model calculations on particles influencing atmospheric chemistry. * Meteorological reference data bases are badly needed for the success of this network. Martin Fuellekrug digged out climatalogical cloud information from the ICSSP project and the German Weather Service can contribute satellite based black body radiation images. One may consider to approach Eumetsat to establish an online data base of satellite images for reference. Proposals) * A proposal has been mailed off to Minerva to establish a firm collaboration with Colin Price in the associated member state Israel. The envisioned work deals with a comparison between global lightning flash location and the Earths black body radiation: fuellekrgeophysikuni-frankfurtde. Publications) * The first results of global lightning triangulation by use of Schumann resonances are published in the Feb. 1 issue of Geophysical Research Letters.