Probability of lightning hits to tall structures taking account of upward lightning

It was revealed that serious lightning faults of high voltage power transmission lines in winter along the coastal area of the Sea of Japan were due to upward lightning initiated from transmission towers. Wind turbines in the same region, reportedly suffer from high lightning fault rate, must also generate frequent upward lightning. Taking account of the aerological data which indicate the heights of the charged region in thunderclouds, a method to evaluate frequency of upward lightning from tall structures in cold regions of Japan in winter is proposed. With this new method, it is possible to evaluate the probability of lightning hits to tall structures in Japan through the year.