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Vonnegut, Bernard

Publications and source records attributed to Vonnegut, Bernard.

Observations of lightning in the stratosphere

An examination and analysis of video images of lightning, captured by the payload bay TV cameras of the space shuttle, provided a variety of examples of lightning in the stratosphere above thunderstorms. These images were obtained on several recent shuttle flights while conducting the Mesoscale Lightning Experiment (MLE). The images of stratospheric lightning illustrate the variety of filamentary and broad vertical discharges in the stratosphere that may accompany a lightning flash. A typical event is imaged as a single or multiple filament extending 30 to 40 km above a thunderstorm that is illuminated by a series of lightning strokes. Examples are found in temperate and tropical areas, over the oceans, and over the land.

Boeck, William L.↗

Lightning to the upper atmosphere: A vertical light pulse from the top of a thunderstorm as seen by a payload bay TV camera of the space shuttle

An examination and preliminary analysis of video images of thunderstorms as seen by a payload bay TV camera of the Space Shuttle provided examples of lightning in the stratosphere above thunderstorms. These images were obtained on several recent Shuttle flights while conducting the Mesoscale Lightning Experiment (MLE). MLE was an experiment to obtain night time images from space of large storm complexes with lightning. These images are used to provide data for the design of specialized instrumentation which will provide quantitative measurements of global lightning. Eight video sequences were selected because they illustrate near vertical discharges in the stratosphere above thunderstorms. Although there are previous reports in the literature, these are the first images from the viewpoint of an orbiting spacecraft. The written material is primarily a companion to a video presentation.

Boeck, William L.↗

Electrical measurements over active thunderstorms

During the summer of 1986, the air conductivity and the vertical electric field were measured over active thunderstorms from a high altitude U-2 airplane. The conductivity at 20 km remained relatively steady above storms with variations less than + or - 15 percent while vertical electric fields in excess of 5 kV/m were regularly observed. Estimates of the storm generator current and the C.T.R. Wilson (i.e., conduction) current can be obtained using the current densities derived from the conductivity and field measurements and integrated over area. Upward flowing currents of 0.05 to 7.7 A were observed with an average of 2.2 A. More importantly, the U-2 data show that the storm current varies linearly with flash rate, therefore, the average charge transfer per discharge should be independent of storm development or activity.

Blakeslee, Richard J.↗