Observed Ocean Surface Winds and Mixed Layer Currents Under Tropical Cyclones: Asymmetric Characteristics

Tropical cyclones (TC) transfer kinetic energy to the upper ocean and thus accelerate mixed layer (OML) currents. However, quantitative link between near-surface currents high wind speeds, under extreme weather conditions, remains poorly understood. In this study, we use multi-mission satellites drifting-buoy observations investigate connections TC surface winds currents, including their spatial distribution characteristics. Observed ageostrophic current speeds in OML increase linearly with (for range 20–50 m/s). The ratios of are found vary quadrants. particular, mean ratio is around 2% left-front left-rear quadrants relatively small variability, compared 4% right-front right-rear quadrants, much higher variations. Surface both exhibit strong asymmetric features, largest on right side. eyewall region Hurricane Igor, (e.g., about 47 m/s) induce (about 2 directional rotations resonant dependent location within storm. Wind directions approximately aligned quadrant; a difference 90° occurs discrepancy quadrant smaller. Reliable wind-current relation, support published theories developed idealized numerical experiments explain response TCs.