Bias Elimination and Scatter in Lightning Location by the VLF Arrival Time Difference Technique

Abstract

In the very low frequency (VLF) band lightning flashes are detectable at ranges of several thousand kilometers. Studies of experimental data show that if systematic biases were eliminated from the U.K. Meteorological Office's VLF arrival time difference (ATD) flash locating (fixing) system, the residual ATD scatter would amount to 1.4?2 µs. For the operational outstation network this would give stroke fixing errors below 1.2 km over most of western Europe. Techniques are presented for the elimination of bias to approach this precision. At longer ranges propagation effects, including those due to terrain conductivity, must he considered.