Physics – Optics
Scientific paper
Dec 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004agufmae52a..03g&link_type=abstract
American Geophysical Union, Fall Meeting 2004, abstract #AE52A-03
Physics
Optics
3324 Lightning, 3332 Mesospheric Dynamics, 3394 Instruments And Techniques, 3304 Atmospheric Electricity, 0649 Optics
Scientific paper
In the 15 years since the accidental discovery of optical flashes above thunderstorms [Franz et al, 1990], now commonly termed sprites, the wide variety of spatial and temporal characteristics exhibited by these phenomena has challenged modeling efforts. The highly dynamic and variable structures observed in sprites can be classified either in terms of basic geometric descriptions (``cylinders," ``tendrils," ``branches," etc.) or by their apparent relation to features previously observed in laboratory gas discharges (i.e. ``streamers" and ``diffuse glow"). High-resolution imagery shows that the lower portion of a sprite typically consists of downward branching filaments, or positive streamers, while the middle to upper portions are made up of upward branching filaments, or negative streamers. The topmost part of a sprite is generally amorphous, or diffuse glow. Filamentary structures (streamers) have been observed to range in width from ˜20 - 200 m with the radius having some altitude dependence. Much of the observed streamer and diffuse glow structure can be explained in terms of conventional electrical gas discharge physics. Some features such as beads and low-altitude diffuse glows, however, are currently unexplained by any sprite model. This presentation describes the spatio-temporal characteristics of several sprites with various features as observed by 1) a high-spatial-resolution telescope, previously described in Gerken et al. [2000], with spatial resolution down to tens of meters, and ˜17 ms temporal resolution; and 2) similar events observed by a high-temporal-resolution ``high speed imager" with 1 ms temporal and approximately 300 m spatial resolution, previously described in Stenbaek-Nielsen et al. [2000]. Franz. R. C., R. J. Nemzek, and J. R. Winckler, Television image of a large upward electrical discharge above a thunderstorm, Science, 249, 48, 1990. Gerken, E. A., U. S. Inan, and C. P. Barrington-Leigh, Telescopic imaging of sprites, Geophys. Res. Lett., 27, 2637, 2000. Stenbaek-Nielsen, H. C., D. R. Moudry, E. M. Wescott, D. D. Sentman, and F. T. Sao Sabbas, Sprites and possible mesospheric effects, Geophys. Res. Lett., 27, 3829, 2000.
Gerken Elizabeth
Moudry Dana
No associations
LandOfFree
Observations of Sprites Using High Spatial and Temporal Resolution Instruments does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Observations of Sprites Using High Spatial and Temporal Resolution Instruments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observations of Sprites Using High Spatial and Temporal Resolution Instruments will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1455499