# 艾克曼解释动画 / Ekman explanation

由 Manim Community 0.22 渲染，中英双语屏幕文字，无配音。
Idealized teaching animation with bilingual on-screen text; no narration.

风应力、湍流应力与科氏效应共同决定风生边界层流动。经典深水、恒定涡黏性、定常模型中，表层流偏转45度，速度随深度指数衰减并旋转。俯视箭头是不同深度的速度，不是单个粒子的轨迹。
Wind stress, turbulent stress and rotation govern the wind-driven boundary layer. The classical steady, deep-water, constant-viscosity solution has a 45-degree surface angle and exponentially decaying, rotating velocity with depth. The arrows are depth-dependent velocities, not particle trajectories.

净体积输运（每单位宽度）M=(tau_y,-tau_x)/(rho*f)，单位m²/s。北半球在风右侧90度，南半球在左侧。此结论要求定常、旋转边界层的适用平衡及可忽略的深层应力；现实海岸、瞬变、赤道和强锋面等情况需额外分析。
Net volume transport per unit width is M=(tau_y,-tau_x)/(rho*f), in m²/s, under the applicable steady rotating boundary-layer balance and negligible stress at depth. Surface angles are not universally 45 degrees.

Sources:
- https://oceanservice.noaa.gov/education/tutorial_currents/04currents4.html
- https://www.pmel.noaa.gov/news-and-media/highlights/steady-state-ocean-response-wind-forcing-extratropical-frontal-regions

Render:
python -m manim -qm ekman_animation.py EkmanExplanation