Previous studies have linked interannual variability of tropical cyclone (TC) intensity in the North Atlantic basin (NA) to Sahelian rainfall, vertical shear of the environmental flow, and relative sea surface temperature (SST). In this study, the contribution of TC track changes to the interannual variations of intense hurricane activity in the North Atlantic basin is evaluated through numerical experiments. It is found that that observed interannual variations of the frequency of intense hurricanes during the period 1958–2017 are dynamically consistent with changes in the large-scale ocean/atmosphere environment.Track changes can account for ～50％ of the interannual variability of intense hurricanes, while no significant difference is found for individual environmental parameters between active and inactive years. The only significant difference between active and inactive years is in the duration of TC intensification in the region east of 60°W. The duration increase is not due to the slow-down of TC translation. In active years, a southeastward shift of the formation location in the region east of 60°W causes TCs to take a westward prevailing track, which allows TCs to have a longer opportunity for intensification. On the other hand, most TCs in inactive years take a recurving track, leading to a shorter duration of intensification. This study suggests that the influence of track changes should be considered to understand the basin-wide intensity changes in the North Atlantic basin on the interannual time scale.

Jun LU;Liguang WU;Shunwu ZHOU

Key Laboratory of Meteorological Disaster,Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Joint Center for Data Assimilation Research and Applications,Nanjing University of Information Science and Technology,Nanjing 210031,China;Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences,Fudan University,Shanghai 200433,China;Innovation Center of Ocean and Atmosphere System,Zhuhai Fudan Innovation Research Institute,Zhuhai 518057,China

大气科学进展（英文版）

[1]Jun LU;Liguang WU;Shunwu ZHOU-.Quantifying the Contribution of Track Changes to Interannual Variations of North Atlantic Intense Hurricanes)[J].大气科学进展（英文版）,2022(02):260-271

Hurricanes,Sahelian,hurricanes,recurving

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