摘要：A randomly stepped leader propagation model is developed to study gigantic jets, a new type of lightning, connecting thunderclouds to the ionosphere. The thundercloud is considered as one electrode igniting gigantic jets and the ionosphere is assumed as the other. The propagation of stepped leader is considered as a field controlled random growth process. The electric field is produced due to the thundercloud charges and the self-consistently propagating leader. A leader propagation probability is proposed to determine whether the leader grows at the next step and what the step direction of the leader is in case of growth. The results show that leader propagation spans ~72 km from igniting position to the ionosphere. The simulation of leader propagation appears to be in agreement with the structure of observed gigantic jets.
