The present study investigates the integrated ocean response to tropical cyclones (TCs) in the South Pacific convergence zone through a complete ocean heat budget. The TC impact analysis is based on the comparison between two long-term (1979–2003) oceanic simulations forced by a mesoscale atmospheric model solution in which extreme winds associated with cyclones are either maintained or filtered. The simulations provide a statistically robust experiment that fills a gap in the current modeling literature between coarse-resolution and short-term studies. The authors’ results show a significant thermal response of the ocean to at least 500-m depth, driven by competing mixing and upwelling mechanisms. As suggested in previous studies, vertical mixing largely explains surface cooling induced by TCs. However, TC-induced upwelling of deeper waters plays an unexpected role as it partly balances the warming of subsurface waters induced by vertical mixing. Below 100 m, vertical advection results in cooling that persists long after the storm passes and has a signature in the ocean climatology. The heat lost through TC-induced vertical advection is exported outside the cyclogenesis area with strong interannual variability. In addition, 60% of the heat input below the surface during the cyclone season is released back to the oceanic mixed layer through winter entrainment and then to the atmosphere. Therefore, seasonal modulation reduces the mean surface heat flux due to TCs to about 3 × 10−3 PW in this region exposed to 10%–15% of the world’s cyclones. The resulting climatological anomaly is a warming of about 0.1°C in the subsurface layer and cooling below the thermocline (less than 0.1°C).

In the decades, the use of scatterometer data allowed to demonstrate the global ubiquity of the ocean mesoscale thermal feedback (TFB) and current feedback (CFB) effects on surface winds and stress. Understanding these air‐sea interactions is of uttermost importance as the induced atmospheric anomalies partly control the ocean circulation and thus can influence the Earth climate. Whether the TFB and CFB effects can be disentangled, and whether satellite scatterometers can properly reveal them, remain rather unclear. Here, using satellite observations and ocean‐atmosphere coupled mesoscale simulations over 45°S to 45°N, we show that the CFB effect can be properly characterized and unraveled from that due to the TFB. We demonstrate that the TFB can be unambiguously characterized by its effect on the stress (and wind) divergence and magnitude. However, its effect on the wind and stress curl is contaminated by the CFB and thus cannot be estimated from scatterometer data. Finally, because scatterometers provide equivalent neutral stability winds relative to the oceanic currents, they cannot characterize adequately the CFB wind response and overestimate the TFB wind response by ≈25%. Surface stress appears to be the more appropriate variable to consider from scatterometer data.

Ocean‐Waves‐Atmosphere (OWA) exchanges are not well represented in current Numerical Weather Prediction (NWP) systems, which can lead to large uncertainties in tropical cyclone track and intensity forecasts. In order to explore and better understand the impact of OWA interactions on tropical cyclone modeling, a fully coupled OWA system based on the atmospheric model Meso‐NH, the oceanic model CROCO, and the wave model WW3 and called MSWC was designed and applied to the case of tropical cyclone Bejisa (2013–2014). The fully coupled OWA simulation shows good agreement with the literature and available observations. In particular, simulated significant wave height is within 30 cm of measurements made with buoys and altimeters. Short‐term (< 2 days) sensitivity experiments used to highlight the effect of oceanic waves coupling show limited impact on the track, the intensity evolution, and the turbulent surface fluxes of the tropical cyclone. However, it is also shown that using a fully coupled OWA system is essential to obtain consistent sea salt emissions. Spatial and temporal coherence of the sea state with the 10 m wind speed are necessary to produce sea salt aerosol emissions in the right place (in the eyewall of the tropical cyclone) and with the right size distribution, which is critical for cloud microphysics.

In this paper, we explore the global responses of surface temperature, chlorophyll, and primary production to tropical cyclones (TCs). Those ocean responses are first characterized from the statistical analysis of satellite data under ~1000 TCs over the 1998–2007 period. Besides the cold wake, the vast majority of TCs induce a weak chlorophyll response, with only ~10% of induced blooms exceeding 0.1 mg m⁻³. The largest chlorophyll responses mostly occur within coastal regions, in contrast to the strongest cold wakes that generally occur farther offshore. To understand this decoupling, we analyze a coupled dynamical‐biogeochemical oceanic simulation forced by realistic wind vortices applied along observed TC tracks. The simulation displays a realistic spatial structure of TC‐induced blooms and its observed decoupling with TC cold wakes. In regions of strong TC energy input, the strongest cold wakes occur in regions of shallow thermocline (<60 m) and the strongest blooms in regions of shallow nitracline and/or subsurface chlorophyll maximum (<60 m). Shallow thermoclines are found over many open ocean regions, while regions of shallow nitracline and/or subsurface chlorophyll maximum are most prominent in near‐coastal areas, explaining the spatial decoupling between the cold and bloom wakes. The overall TC contribution to annual primary production is weak and amounts to ~1%, except in a few limited areas (east Eurasian coast, South tropical Indian Ocean, Northern Australian coast, and Eastern Pacific Ocean in the TC‐prone region) where it can locally reach up to 20–30%. Nearly 80% of this TC‐induced annual primary production is the result of the biogeochemical response to the 30% strongest TCs.