HR: 1330h
AN: AE32A-0167    [PDF]
TI: On the Dynamics of the North-South Seasonal Migration of Global Lightning
AU: * Satori, G
EM: satori@ggki.hu
AF: Geodetic and Geophysical Research Institute, HAS, Csatkai u. 6-8., Sopron, H-9400 Hungary
AU: Williams, E R
EM: earlew@ll.mit.edu
AF: Massachusetts Institute of Technology, Parsons Laboratory, MIT 48-336B, Cambridge, MA 02445 United States
AU: Boccippio, D J
EM: Dennis.Boccippio@nasa.gov
AF: NASA/MSFC, SD-60, Huntsville, AL 35812 United States
AB: The daily Schumann resonance (SR) frequency patterns are mainly determined by the lightning source-observer configuration consequently their variations are indicative for the changes of global lightning position. Four basic types of daily frequency patterns have been distinguished corresponding to the four seasons observed for each SR mode at Nagycenk, Hungary. The number of days with daily frequency patterns characteristic for a season were very different. Similar daily frequency patterns have been observed during 160-165 consecutive days from the beginning of November to the first part of April in any year of SR observations at Nagycenk. The same time sequences (four seasons with different lengths) can be recognized in the global lightning distribution observed by OTD (Optical Transient Detector) (Christian et al., 2003) as it was shown in the seasonal distributions of the daily frequency patterns of Shumann resonances. The land/ocean ratio is smaller in the Southern Hemisphere than in the Northern Hemisphere. It seems that oceanic thermodynamical properties (large thermal inertia) are manifested in the dynamics (speed) of the north-south lightning migration identified by the long lasting (160-165 days) southern position of global lightning in the Southern Hemisphere summer and by the time lag of the northward lightning migration in spring. The spring-fall asymmetry of the migration speed is attributed to the different thermodynamical properties of land and ocean.
DE: 3304 Atmospheric electricity
DE: 3324 Lightning
SC: Atmospheric and Space Electricity [AE]
MN: 2003 Fall Meeting