Bidirectional energy transfer across scales in geophysical turbulence
中国科学院上海天文台-地球物理和天体物理流体力学系列讲座
报告题目：Bidirectional energy transfer across scales in geophysical turbulence
报告人： 谢金翰 副教授 (北京大学)
报告地点: 三楼中会议室
报告时间：2025年 9 月 23 日（周二） 上午10:00
报告摘要：
In 1941, Kolmogorov proposed the 4/5 law for the inertial range in three-dimensional isotropic turbulence, which links measurable third-order structure functions with energy transfer. The inertial-range theories are applied to quantify the direction and magnitude of energy transfer in natural turbulence. However, the applicability of these theories is limited due to the effects of forcing scale and bidirectional energy transfer. Thus, expressions for structure functions beyond the inertial range are required. We derive a forcing-scale-resolving global expression that captures the bidirectional energy transfer. We apply this expression to analyse the drifter data in the Gulf of Mexico and provide evidence for bidirectional energy transfer in ocean turbulence. By analyzing the third-order structure functions of measured data for solar winds, we show how simultaneous upscale and downscale energy transfers occur in solar wind, leading statistically to equipartition of the turbulent energy flux. Our study sheds light on the paradigm of the existence of dual energy cascades in astrophysical plasmas, identifying the scales at which energy sources act in the magnetohydrodynamic regime, driving turbulent dynamics in the solar wind. These findings in the ocean and solar imply the universal feature of bidirectional energy transfer in geophysical turbulence.报告人简介：
附件下载：
Speaker：顾浩 副教授 (中山大学)
Time：2025年 11 月 19 日（周三） 上午10:30
Location：三层中会议室
Speaker：徐麒 博士 (国家空间科学中心)
Time：2025年 7 月 24 日（周四） 上午10:30
Location：比邻星协同交流室A
Speaker：袁龙辉 (ETH Zurich)
Time：2025年 7 月 17 日（周四） 上午10:00
Location：三楼中会议室
Speaker：李牧 教授(深圳技术大学)
Time：2025年 6 月 27 日（周五） 下午2:00
Location：三楼中会议室
