5:15 PM - 6:45 PM
[MIS06-P03] Estimation of lightning strike location and energy by using Infrasound sensors
Keywords:infrasound, lightning
In the Philippines, heavy rainfall often caused by monsoons and led to numerous casualties. The correlation between precipitation and lightning strike frequency has been studied. Based on this relationship, if the total energy of lightning could be estimated, it could be possible to predict precipitation.
Since the energy of sound waves is proportional to the square of the sound pressure, it can be expected to detect more accurate lightning activity than electromagnetic wave observations in energy estimation. Sound waves have the property that the lower the frequency, the farther they can propagate. This research is to estimate the sound energy of infrasound caused by lightning by taking advantage of this property. We conducted multi-point infrasound observations to estimate the location, including the altitude, of lightning.
Lightning observations were conducted in Manila, Tokyo, and Hokkaido University's Sapporo campus using infrasound sensor. When plate sensor detected lightning, infrasound sensor observed thunderstorm sound around 8~10 Hz in Manila. Lightning location were estimated by Time Difference of Arrival (TDOA) method using two observations in Tokyo, and refereed LIDEN's lightning strike location observed by Japan Meteorological Agency. Lightning sound height was estimated around 11,000 m. Furthermore, utilizing these results, the lightning sound energy was calculated 9.68×104J from observations at the Sugamo site and 9.60×104J at the Fujisan-NPO site in Tokyo. The estimated lightning sound energy is approximately four orders smaller in magnitude than the total energy of a lightning strike that causes a 20C discharge.
At this stage, we have estimated lightning energy for only one event in the Tokyo observation data, but we are currently analyzing the data obtained from other observation as well.
Since the energy of sound waves is proportional to the square of the sound pressure, it can be expected to detect more accurate lightning activity than electromagnetic wave observations in energy estimation. Sound waves have the property that the lower the frequency, the farther they can propagate. This research is to estimate the sound energy of infrasound caused by lightning by taking advantage of this property. We conducted multi-point infrasound observations to estimate the location, including the altitude, of lightning.
Lightning observations were conducted in Manila, Tokyo, and Hokkaido University's Sapporo campus using infrasound sensor. When plate sensor detected lightning, infrasound sensor observed thunderstorm sound around 8~10 Hz in Manila. Lightning location were estimated by Time Difference of Arrival (TDOA) method using two observations in Tokyo, and refereed LIDEN's lightning strike location observed by Japan Meteorological Agency. Lightning sound height was estimated around 11,000 m. Furthermore, utilizing these results, the lightning sound energy was calculated 9.68×104J from observations at the Sugamo site and 9.60×104J at the Fujisan-NPO site in Tokyo. The estimated lightning sound energy is approximately four orders smaller in magnitude than the total energy of a lightning strike that causes a 20C discharge.
At this stage, we have estimated lightning energy for only one event in the Tokyo observation data, but we are currently analyzing the data obtained from other observation as well.