Fig. 5From: Occurrence characteristics and lowest speed limit of subauroral polarization stream (SAPS) observed by the SuperDARN Hokkaido East radarSimilar to Fig. 4, with the black curve used for the test as latitudinal threshold to identify flows as SAPS. For details of determining this curve, please refer to the main text. The other parts are in the same format as Fig. 4c with 150 m/s thresholdBack to article page