[P-EM11] Space Weather and Space Climate

[PEM11-P17] Estimation of geomagnetically induced current (GIC) using the global MHD simulation of the magnetosphere 6

*Shinichi Watari¹, Aoi Nakamizo¹, Yusuke Ebihara² (1.National Institute of Information and Communications Technology, 2.Research Institute for Sustainable Humanosphere, Kyoto University)

Keywords:geomagnetically induced current (GIC), global MHD simulation of the magnetosphere, geomagnetic storm

We have been studying the calculation of geomagnetically induced current (GIC) using the real-time calculation result of the NICT global MHD simulation. It is necessary for the GIC calculation to consider (1) calculation of geomagnetic filed variation using the simulation, (2) calculation of electric field variation from the geomagnetic field variation, and (3) calculation of GIC from the electric field variation.
We have developed a method to calculate electric field variation with 2 degrees by 2 degrees resolution using the magnetic field variation obtained from the simulation and the underground conductivity model with 2 degrees by 2 degrees resolution and a method to calculate GIC using a simplified power line model.
On the electric field calculation, we tried to calculate magnetic and electric field variations at high latitude region on the past intense geomagnetic storm such as the October 2003 storm. On the GIC calculation from the electric field, we made a power line model around substations of GIC measurements and calculated GIC for the assumed direction of electric field. We calculated GIC applying to the past electric field data observed at Kakioka to the power line model and compared it with the measured GIC and studied a method to improve the result of the GIC calculation using the measured GIC data. We will report on these results.