Submesoscale eddies are often seen in high‐resolution satellite‐derived ocean color images. To efficiently identify these eddies from surface chlorophyll data, here, we develop an automatic submesoscale eddy detection method and apply it to the South China Sea. The detected submesoscale eddies are found to have a radius of 13 ± 5 km and an aspect ratio of 0.5 ± 0.2, with a notable predominance of cyclones. Further investigation reveals that the surface structure of these eddies displays a unique “cat's‐eye” pattern, and the eddies become more circular with increasing eddy radius. Submesoscale eddies can strongly regulate surface chlorophyll via horizontal advection while they have less coherent signatures in sea surface temperature. These findings may help to improve submesoscale parameterizations in Earth system models.

Mesoscale eddies are ubiquitous features of the global ocean circulation and play a key role in transporting ocean properties and modulating air–sea exchanges. Anticyclonic and cyclonic eddies are traditionally thought to be associated with anomalous warm and cold surface waters, respectively. Using satellite altimeter and microwave data, here we show that surface cold-core anticyclonic eddies (CAEs) and warm-core cyclonic eddies (WCEs) are surprisingly abundant in the global ocean—about 20% of the eddies inferred from altimeter data are CAEs and WCEs. Composite analysis using Argo float profiles reveals that the cold cores of CAEs and warm cores of WCEs are generally confined in the upper 50 m. Interestingly, CAEs and WCEs alter air–sea momentum and heat fluxes and modulate mixed layer depth and surface chlorophyll concentration in a way markedly different from the traditional warm-core anticyclonic and cold-core cyclonic eddies. Given their abundance, CAEs and WCEs need to be properly accounted for when assessing and parameterizing the role of ocean eddies in Earth’s climate system.

Although the surface eddy kinetic energy (EKE) has been well studied using satellite altimeter and surface drifter observations, our knowledge of EKE in the ocean interior is much more limited due to the sparsity of subsurface current measurements. Here we develop a new approach for estimating EKE over the full depth of the global ocean by combining 20 years of satellite altimeter and Argo float data to infer the vertical profile of eddies. The inferred eddy profiles are surface‐intensified at low latitudes and deep‐reaching at mid‐ and high latitudes. They compare favorably to the first empirical orthogonal function obtained from current meter velocities. The global‐integrated EKE estimated from the inferred profiles is about 3.1 × 10¹⁸ J, which is close to that estimated from the surface mode (3.0 × 10¹⁸ J) but about 30% smaller than that estimated from the traditional flat bottom modes (4.6 × 10¹⁸ J).

Wind power input to oceanic near‐inertial oscillations (NIOs) plays a crucial role in sustaining the global ocean conveyor belt. However, the impact of tropical cyclones (TCs) on wind power input to NIOs, despite being the most vigorous atmospheric dynamics capable of exciting NIOs, is often overlooked in global estimations due to their transient nature and a lack of observations. Utilizing hourly wind and ocean current records, we quantified the wind power on NIOs induced by TCs from 1990 to 2019. Our findings reveal that the wind power on NIOs due to TCs is estimated to be between 0.028 and 0.065 TW, which accounts for a significant proportion, that is, 8%–17%, of that over the globe. This study highlights the importance of incorporating the wind power induced by TCs when estimating the global wind power on NIOs, as its impact is non‐negligible. Our findings contribute to a better understanding of the global energy balance by improving the estimation of wind power on NIOs.

Utilizing two-dimensional sea level anomalies from the Surface Water and Ocean Topography (SWOT) wide-swath altimeter, we conduct a global census of fine-scale eddies (with equivalent radii < 30 km) that are beyond the resolution capacity of traditional altimeters. We find that these eddies are concentrated in regions with energetic mesoscale currents such as western boundary current extensions, the Antarctic Circumpolar Current and prominent interior frontal zones. While these eddies are smaller than classical mesoscale eddies (O(100) km), they exhibit dynamics distinct from the mesoscale, including a pronounced winter peak in occurrence frequency and a striking dominance of cyclonic over anticyclonic polarities. A global composite reveals a net enhancing effect of these fine-scale eddies on surface chlorophyll-a (approximately +7% within eddy cores relative to surrounding waters). Our findings shed light on the dynamical characteristics and surface chlorophyll-a signatures of fine-scale ocean eddies, necessitating their adequate representation in next-generation ocean models.

Mesoscale eddies, prevalent across the global ocean, play a crucial role in the transport and mixing of climate‐sensitive tracers such as heat, salt, and nutrients. While traditional quasi‐geostrophic theory predicts symmetric kinematics and equivalent material transport by cyclonic and anticyclonic eddies, our analysis of satellite altimeter and surface drifter data shows a significant asymmetry in drifter distribution inside ocean eddies. We find that globally cyclonic eddies capture about 12.5% more drifters than their anticyclonic counterparts, particularly near eddy centers. Numerical experiments reveal that this asymmetry results from eddy‐wind interactions, which induce anomalous convergence in cyclonic eddies and divergence in anticyclonic eddies, enhancing particle aggregation in cyclones. These findings provide new insights into the distribution of ocean surface buoyant materials, including oil spills, plastics, and other pollutants.