Data is provided in an ASCII comma delimited file which is suitable for processing in a database, spreadsheet, or GIS programme. The stroke count for each cell is shown in a seperate matrix for positive, negative and cloud strokes. Data may also be provided in EXCEL 5.0 format.
A colour PCX file is provided, for each stroke type, to graphically show the relationship between the stroke count in the matrix.
Amplitude analysis shows the make up of ground strokes in an area for a defined time period. The current is an estimate as detected by the sensors. Corresponding reports from two pairs of sensors are required to locate a stroke.
The long range performance is such that some strokes are recorded for all substantial storms. High amplitude strokes produce waves that travel thousands of kilometres. For areas greater than 500 kms from sensors, strokes above 20kA are typically recorded.
The Multi stroke analysis shows the relationship between stroke numbers in a flash, polarity of multiple strokes and combinations of cloud and ground strokes. Subsequent stroke criteria is usually taken as being within a distance of 10 kms and 500 milliseconds. These parameters were developed by the US navy. Other values may be substituted.
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