Lightning prediction system
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A lightning prediction system includes various methods and different apparatus for remotely sensing electrical activity and the potential for lightning occurrence. In the several variant systems and methods, means are provided for the automated prediction of lightning strikes in a set of different functional regions for different times in the future. The system utilizes measurements of many weather phenomena. The types of measurements that can be utilized in approximately the same geographical region as that for which the strike predictions are made. The systems utilizes a correlation network to relate these weather measurements to future lightning strikes.
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[edit] Description
The first lightning prediction system, the Lightning detector, was invented in 1894 by Alexander Stepanovich Popov. It also was the first Radio receiver in the world.
Various systems use different apparatus and methods to detect the electrical potential levels of electrical storms. Storms are illuminated by various means and the information returns are correlated. Various devices provide a system and method for predicting areas where lightning strikes are likely to occur by evaluating radar and temperature data. Radar volume data is analyzed to locate cloud tops that extend above a height corresponding to a temperature line of about 10 C. Areas where cloud tops extend above the height of the 10 C. line and that have a radar composite reflectivity greater than 30 dBZ are designated as probable lightning threat areas. Radar movement is tracked across at least two time periods, and a correlation algorithm predicts the future location of lightning threat areas at predetermined time periods (e.g., 10 minutes, 20 minutes, and 30 minutes) based on predicted radar values. A computer display shows the predicted location of the lightning threat areas for the future time periods.
The method and apparatus remotely sense electrical activity and potential for lightning occurrence. The devices are particularly directed to the use of such a method to detect the electrical alignment of particles in upper levels of electrical storms. Storms are scanned by radar in one or more orthogonal polarizations and the co-polar and cross-polar returns are correlated coherently and incoherently. The correlation coefficient, or a function thereof, is examined to determine the degree of particle alignment, and therefore the degree of electrification and potential for lightning occurrence. The phase of the correlation computation, in coherent processing, also detects particle alignment, which can be incorporated in the predictive decision. Correlation and phase can be displayed, recorded or, utilized for a prediction or warning.
The method used by such systems for detecting lightning as an electrical atmospheric disturbance and for providing an indication of the georaphic position of that disturbance includes the stationing of at least three receivers at known geographic locations in spaced relationship to each other. Signals are encoded at each of the receivers representative of the time of arrival of an electrical indication of an emission from the lightning strike, in relation to a common timing source. All of the encoded signals are transmitted to a central facility and thereafter processed for deriving the position of the lightning strike irrespective of whether the position of the lightning occurred within or outside the perimeter bounded by the three receivers. The system is synchronized with the U.S. Coast Guard LORAN navigation network, and includes various features which permit a more accurate analysis of lightning position.
[edit] Patents
- U.S. Patent 4,792,806, Lightning position and tracking method
- U.S. Patent 5,140,523, Neural network for predicting lightning
- U.S. Patent 5,621,410, Remote prediction of lightning hazards
- U.S. Patent 5,771,020, Lightning locating system
- U.S. Patent 6,246,367, Lightning locating system
- U.S. Patent 6,405,134, Method and apparatus for predicting lightning threats based on radar and temperature data
- U.S. Patent 6,586,920, Lightning detector
- U.S. Patent 6,828,911, Lightning detection and prediction alarm device
- U.S. Patent 7,069,258, Weather prediction method for forecasting selecte events
- U.S. Patent 4,792,806, Lightning position and tracking method
