## Meta data

Descriptions of the system and data can be found via the metadata page (in Swedish).

## Parameters

The information delivered is based on the so called UALF-format (Universal ASCII Lightning Format).

For every delivered stroke the information contains these fields:

Parameter | Description | Acceptable Values |
---|---|---|

timeTick | Date and time in UTC. For json format this is represented as milliseconds since the UNIX epoch (January 1, 1970 00:00:00 UTC). | |

offsetFromTimeTickNs | Offset from time tick in nanoseconds | 0-999999999 |

lat | Latitude of the calculated location in decimal degrees. Coordinate system WGS84. | -90.0000-90.0000 |

lon | Longitude of the calculated location in decimal degrees. Coordinate system WGS84. | -90.0000-90.0000 |

peakCurrent | Estimated peak current in kiloamperes. Including polarity. | -9999-9999 |

multiplicityForFlashData | Multiplicity for flash data. | 0 for stroke data 1-99 for flash |

numberOfSensors | Number of sensors participating in the solution | 2-99 |

degreesOfFreedom | Degrees of freedom when optimizing location | 0-99 |

The following 3 parameters specify a confidence ellipse measuring a 50th percentile confidence region around the given latitude/longitude location. | ||

ellipseAngle | Ellipse angle as a clockwise bearing from 0 degrees North | 0-180.00 |

lengthOfSemiMajorAxis | Length of semi-major axis of ellipse in kilometers (km) | 0-50.00 km |

lengthOfSemiMinorAxis | Length of semi-minor axis of ellipse in kilometers | 0-50.00 km |

chiSquareValue | Chi-squared value from location optimization. A statistical measure of how much deviation exists between sensor data in calculating the lightning stroke location. Note that strokes with chi square >= 10.0 have been excluded for quality reasons. | 0-9.99 |

risetimeOfWaveform | Rise time of the waveform in microseconds (μsec) | 0-99.9 μs |

peakToZeroTime | Peak-to-zero time of the waveform in microseconds | 0-999.9 μs |

maxRateOfRise | Maximum rate-of-rise of the waveform in kA/μsec | 0-999.9 kA/μs |

cloudIndicator | Cloud indicator | 1 = Cloud discharge 0 = Cloud-to-ground |

angleIndicator | Angle indicator. Sensor angle data used to compute position. | 1=Yes 0=No |

signalIndicator | Signal indicator. Sensor signal data used to compute position. | 1=Yes 0=No |

timingIndicator | Timing indicator. Sensor timing data used to compute position. | 1=Yes 0=No |