Abstract:Based on the daily reanalysis data of National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), the sea surface temperature data, atmospheric circulation and oceanic index data of National Climate Prediction Center (NCPC) from 1971 to 2016, this paper recognizes storm tracks in the Northern Hemisphere as a whole, and analyzes the characteristics of multi-scale energy variation and its possible mechanism using the multi-scale energy and vorticity analysis (MS-EVA). The results are summarized as follows. (1) The mean state of climate of many years shows that the kinetic energy source of storm tracks manifests as the available potential energy transmission from large scale to synoptic scale on the middle and upper reaches of storm tracks, and the subsequent energy conversion from potential to kinetic energy on the synoptic scale in the main areas of storm tracks. Besides, there is directly energy transmission from large scale to synoptic scale in the western part of storm tracks. (2) The first mode of EOF shows that with the weakening (intensification) of Siberian storm track and the northern Atlantic storm track, the Pacific storm track shifts northward (southward), and the second mode shows that with the weakening (intensification) of Siberian storm track, the Northern Atlantic storm track shifts northward (southward), and intensifies (weakens) in its middle-eastern part, together with southward (northward) shift of the Pacific storm track. (3) Regression analysis shows that the abnormality of the storm tracks in the northern hemisphere has a close association with the large-scale circulation in different modes. The large-scale fluctuation can affect the multi-scale energy conversion in the area of storm tracks by changing sea temperature and westerly jet, and then affect the anomaly characteristics of the overall storm track.