13:45 〜 15:15
[MIS06-P02] New proposal of the way to detect the lightning position with using high density electrostatic field observation in Metro Manila
★Invited Papers
キーワード：豪雨、雷、マニラ
In Southeast Asia and other regions, torrential rains and flooding damage caused by developing cumulonimbus clouds occur every year. These events cause numerous deaths and housing collapses, and have become a social problem, making it imperative to improve the accuracy of rainfall forecasting due to cumulonimbus clouds.
In this study, conducted as a ULAT (Understanding Lightning and Thunderstorm) project, we focused on lightning, which has a correlation between heavy rainfall and the frequency of occurrence with a time lag of several tens of minutes. The ultimate goal is improving the accuracy of heavy rainfall prediction in Manila, Philippines. The ULAT project aims to utilize lightning and weather data to improve the accuracy of weather forecasts.
The amount of change in the electric field during a lightning strike is obtained by grounding one of two metal plates installed parallel and above and below each other, and determining the voltage between the metal plates before and after the lightning strike. Using the principle of the mirror image method, the three-dimensional location of lightning and the amount of lost electric charge are estimated from data obtained from multiple observation devices installed at multiple locations at high densities.
The estimation method is to estimate the height and amount of lost charge by brute force calculation after obtaining the planar lightning occurrence location. In estimating the lightning occurrence location, the amount of electric field change from each observation point is interpolated by kriging, approximated in a regular circle and estimate the center as lightning place.
This estimation method enables us to estimate the lightning position with an average error of 500 m (1/10 of the instrument interval) within 10 seconds for a single lightning event.
Since the time difference between lightning and heavy rain is several tens of minutes, it is necessary to perform the process from lightning observation to rainfall distribution prediction in a short period of time. Under these constraints, the estimation of lightning parameters within 10 seconds with an average error accuracy of 500 m is expected to make the prediction of heavy rainfall using changes in the electric field more practical.
This research is supported by Science and Technology Research
Partnership for Sustainable Development (SATREPS), Japan Science
and Technology Agency (JST) / Japan International Cooperation Agency (JICA).
In this study, conducted as a ULAT (Understanding Lightning and Thunderstorm) project, we focused on lightning, which has a correlation between heavy rainfall and the frequency of occurrence with a time lag of several tens of minutes. The ultimate goal is improving the accuracy of heavy rainfall prediction in Manila, Philippines. The ULAT project aims to utilize lightning and weather data to improve the accuracy of weather forecasts.
The amount of change in the electric field during a lightning strike is obtained by grounding one of two metal plates installed parallel and above and below each other, and determining the voltage between the metal plates before and after the lightning strike. Using the principle of the mirror image method, the three-dimensional location of lightning and the amount of lost electric charge are estimated from data obtained from multiple observation devices installed at multiple locations at high densities.
The estimation method is to estimate the height and amount of lost charge by brute force calculation after obtaining the planar lightning occurrence location. In estimating the lightning occurrence location, the amount of electric field change from each observation point is interpolated by kriging, approximated in a regular circle and estimate the center as lightning place.
This estimation method enables us to estimate the lightning position with an average error of 500 m (1/10 of the instrument interval) within 10 seconds for a single lightning event.
Since the time difference between lightning and heavy rain is several tens of minutes, it is necessary to perform the process from lightning observation to rainfall distribution prediction in a short period of time. Under these constraints, the estimation of lightning parameters within 10 seconds with an average error accuracy of 500 m is expected to make the prediction of heavy rainfall using changes in the electric field more practical.
This research is supported by Science and Technology Research
Partnership for Sustainable Development (SATREPS), Japan Science
and Technology Agency (JST) / Japan International Cooperation Agency (JICA).