is the antarctic circumpolar current a surface current

Schmale, J., Baccarini, A., Thurnherr, I., Henning, S., Efraim, A., Regayre, 1, Australian Antarctic Data Centre, https://doi.org/10.26179/5e9d038c396f2, 2020.a, b, Donelan, M.A., Hamilton, J., and Hui, W.H.: Directional spectra of Overall, there is a good agreement between reconstructed and observed sea state. Collocated SAR spectra from Sentinel-1A/1B missions within area of 0.50.5 and maximum temporal difference of 6h were retrieved from the Australian Ocean Data Network (AODN) portal (Khan etal.,2020b). Average sea ice concentration during the expedition is overlaid in panels (c) and (d). Observations of the Antarctic Circumpolar Current over the Udintsev Fracture Zone, the narrowest choke point in the Southern Ocean, J. Geophys. Open Arch., 15, https://doi.org/10.1002/essoar.10504508.1, in review, (2020), Thurnherr etal. The spectral peak that satisfies the condition. The Antarctic Circumpolar Current (ACC) is the largest wind-driven current on Earth. Antarctic Circumpolar Current - Wikipedia Circumpolar structure and distribution of the Antarctic Circumpolar A large body of recent oceanographic research has shown that the Antarctic Circumpolar Current (ACC), an ocean current that flows from west to east around Antarctica, plays a crucial role in global ocean circulation. Although the expedition took place during the Austral summer, the data set contains records of severe sea states, in excess of the 90th percentile expected for the season. Ocean. Southern Ocean, J. Atmos. Further, it attenuates waves, modulating airsea fluxes and mixing (Thomas etal.,2019). But the uncertainties are too high for a reliable estimate of the time of AMOC tipping.. Res. https://doi.org/10.5281/zenodo.1443511, 2018.a, b, Young, I.R. and Ribal, A.: Multiplatform evaluation of global trends in wind (2020), and Suaria etal. The densest water in ocean currents is the coldest and saltiest. An alternative name for the ACC is the West Wind Drift. Oceanic Waves: Field and Laboratory Experiments, Geophys. Circumpolar structure and distribution of the Antarctic Circumpolar Further, measurements normally concentrate on the lower atmosphere and/or the upper ocean (not necessarily concomitantly), while waves are generally not monitored. finite depth. Walton, D, W.H. and Thomas, J.: Cruise Report Antarctic Circumnavigation Atmos. Expedition 2017: WaMoS Data Product, Ver. Derkani, M., Alberello, A., and Toffoli, A.: Antarctic Circumnavigation Khan, S., Echevarria, E., and Hemer, M.: Ocean swell comparisons between SAR technology provides images that can be converted into directional wave energy spectra (Khan etal.,2020a). In response to this issue, a unique data set of sea state parameters, comprising concomitant observations of winds, waves, and surface currents, was recorded in the Southern Ocean during the Antarctic Circumnavigation Expedition, from December2016 to March2017. The Southern Ocean has a profound impact on the Earth's climate system. https://doi.org/10.1029/2018RG000631, 2019.a, b, Fadaeiazar, E., Leontini, J., Onorato, M., Waseda, T., Alberello, A., and NOAA/AOML Altimetry Products C., Royer, S.-J., Estrada, M., Sala, M.M., and Sim, R.: Distribution Lett., 48, The study published Tuesday in the journal Nature Communications suggests that continued warming will push the AMOC over its tipping point around the middle of this century. Leg1 and Leg3 mostly covered the open ocean north of the 60th parallel, roughly between the sub-Antarctic and polar fronts delimiting the Antarctic Circumpolar Current (Fig.2a and b). Spectral evolution, Coastal Eng., 29, 7999, Offshore Res. Sverdrup dynamics in their usual form cannot be applied to flows within a zonally unbounded ocean, and as a consequence the dynamics of the ACC have long been a topic of debate. Toffoli, A.: Fourier amplitude distribution and intermittency in mechanically generated surface gravity waves, Phys. The basic configuration for the X-band radar requires an antenna with rotation speed of 24rpm, horizontal opening angle of 0.9, and radar pulse width of 80ns. source BEM solver NEMOH, in: Proc. Open Arch., 15, Li, M., Liu, J., Wang, Z., Wang, H., Zhang, Z., Zhang, L., and Yang, Q.: Products. M.-H., Pujol, M.-I., Ballarotta, M., Durand, I., and Provost, C.: Metal Accumulations in Two Extreme-Environment Amphipods, Hadal Eurythenes gryllus and Antarctic Pseudorchomene plebs. Explainer: how the Antarctic Circumpolar Current helps - CSIROscope e2020GL091187. Overview. The ocean's dominant feature, extending up to two miles deep and as much as 1,200 miles wide, is the Antarctic Circumpolar Current, by far the largest current in the world. Inversion of marine radar images for surface wave analysis, J. Pt. The short wavelets (ripples) on the ocean surface contribute notably to reflection, while long-wave components modulate the returning signal. The Antarctic Circumpolar Current, or ACC, is the strongest ocean current on our planet. Contrary to wind and wave parameters, current speeds from WaMoS-II show notable differences from satellite observations. Significant wave heights match better with satellite observations than wind speeds, with RMSE0.42m, R0.93, and SI0.155. of Longer-Term Variability, Rev. MHD and KGH calibrated and analysed the data. Phys., 20, 58115835. Antarctic sea ice levels dive in 'five-sigma event', as experts flag Lett., 42, 85478554, The hadal zone and Antarctic Ocean are two of the least-explored habitats. The data set includes observations around the Southern Ocean from latitude 34 to 74 south. reliability of surface current measurements by X-Band marine radar, Remote Sens., 11, 1030, https://doi.org/10.3390/rs11091030, 2019.a, b, Holthuijsen, L.H.: Waves in oceanic and coastal waters, Cambridge University Oceanography Flashcards | Quizlet wind-generated ocean waves, Philos. Southern Ocean - The World Factbook In turn, waves (in combination with wind) have a significant feedback to the Antarctic sea ice state, extent, and thickness (e.gWadhams,1986; Bennetts etal.,2017; Alberello etal.,2019a; Vichi etal.,2019; Alberello etal.,2020a). Here, we analyzed the metal accumulations of two amphipod species, Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. However, additional components such as inertial oscillations (Treguier and Klein,1994) are not taken into account due to the coarse resolution of satellite observations and Ekman components. Biases show both overestimations (especially at the beginning of Leg1 and Leg3) and underestimation (at the end of Leg1 and Leg2) of satellite observations, varying between 6 and 6ms1. wind speed data based on altimeter observations, Sci. Lett., 39, L16606, https://doi.org/10.1029/2012GL052290, 2012.a, Smart, S.M., Fawcett, S.E., Ren, H., Schiebel, R., Tompkins, E.M., A vital system of ocean currents in the Atlantic could collapse within a few decades - an event that would be catastrophic for global weather and "affect every person on the planet." Meas. The P90 shows velocity with maxima in excess of 0.75ms1, especially in the Indian Ocean sector (first half of Leg1). Heat stored in the Earth system: where does the energy go? The largest biases (about 0.5ms1, the same order of magnitude of the current speed itself) were detected primarily at the beginning of Leg1 and at the end of Leg3, where the ship crossed the Agulhas Current, and in Leg2, when crossing the Antarctic marginal ice zone. Find support for a specific problem in the support section of our website. Offshore Change, 3, 509526, https://doi.org/10.1002/wcc.189, 2012.a, Onorato, M., Waseda, T., Toffoli, A., Cavaleri, L., Gramstad, O., Janssen, P. Res., 117, C00J24, https://doi.org/10.1029/2011JC007780, 2012.a, Toffoli, A., Bennetts, L.G., Meylan, M.H., Cavaliere, C., Alberello, A., These effects depend on the view geometry (height and range of the antenna). Data of current speed are from the Copernicus GlobCurrent database https://marine.copernicus.eu (last access: 8July2020) that combines the velocity field of geostrophic surface currents from satellite sensors recorded from 1993 to 2019 (Rio etal.,2014) and modelled Ekman currents, which include components from wind stress forcing obtained from atmospheric system and drifter data. 2021.a, b, Li, M., Liu, J., Wang, Z., Wang, H., Zhang, Z., Zhang, L., and Yang, Q.: Unique current connecting Southern and Indian Oceans - Nature Tatzelt, C., Landwehr, S., Modini, R.L., Tummon, F., Johnson, J.S., Harris, of wave-induced mixing on Antarctic sea ice in a high-resolution ocean model, Ocean Dyn., 69, 737746, 2019.a, Thurnherr, I., Kozachek, A., Graf, P., Weng, Y., Bolshiyanov, D., Landwehr, S., Pfahl, S., Schmale, J., Sodemann, H., Steen-Larsen, H. C., Toffoli, A., Wernli, H., and Aemisegger, F.: Meridional and vertical variations of the water vapour isotopic composition in the marine boundary layer over the Atlantic and Southern Ocean, Atmos. This paper was edited by Giuseppe M.R. Expedition 2017: Motion Sensor and GPS Data, Australian Antarctic Data Centre. Rogue Waves in an Annular Wave Flume, Phys. Its strong winds, All site content, except where otherwise noted, is licensed under the, Wind, waves, and surface currents in the Southern Ocean: observations from the Antarctic Circumnavigation Expedition. Young waves were recorded during all storm events with steepness generally in excess of 0.1. Due to the coarse resolution of satellite data, average values are computed for clusters with spatial resolution of 0.50.5 and temporal resolution of 3h. 2023. C., Royer, S.-J., Estrada, M., Sala, M.M., and Sim, R.: Distribution measurements in Europe: applications of WaMoS II as a sensor for sea state, Atmos. Oceanogr., 5, 750760, 1975.a, Montiel, F., Squire, V.A., and Bennetts, L.G.: Attenuation and directional Figure9Example directional wave energy spectra recorded during ACE (a, c, e) and collocated SAR spectra (b, d, f). Note that the misalignment of high-frequency components with the wind direction in the upper two panels is due to recent wind change. The expedition was conceived to bring together a broad range of Earth Science disciplines with the aim of exploring the interplay of processes in the lower atmosphere, ocean surface, subsurface, and land with simultaneous observations. 'Something weird is going on': search for answers as Antarctic sea ice Concluding remarks are made in the last section. of Longer-Term Variability, Rev. The Antarctic Circumpolar Current (ACC) is the world's strongest ocean current. Res.-Oceans, 126, e2020JC016265, https://doi.org/10.1029/2020JC016265, 2020a.a, Khan, S., Hemer, M., Echevarria, E., and King, E.: Australian Ocean Surface Wind speeds and significant wave heights are compared against collocated satellite observations from altimeter sensors (same data source discussed in the previous session). during the PIPERS 2017 autumn field campaign, Ann. Press, Cambridge, 2007.. For each variable, the dashed line and shading represent the 50th percentile and its interquartile range IQR, respectively, based on climate statistics from satellite observations; the solid line indicates the 90th percentile. Leg2 started with the most extreme storm during ACE; winds reached speeds close to 20ms1, which is well above P90. Sci. and Drivers of Marine Isoprene Concentration across the Southern Ocean, Meiners, K.M., Golden, K.M., Heil, P., Lieser, J.L., Massom, R., Meyer, B., and Williams, G.D.: SIPEX-2: A study of sea-ice physical, biochemical and ecosystem processes off East Antarctica during spring 2012, Deep-Sea Res. Expedition 2017: Motion Sensor and GPS Data, Australian Antarctic Data Centre, https://doi.org/10.4225/15/5A178EF0E5156, 2020b.a, Alberello, A., Bennetts, L., Toffoli, A., and Derkani, M.: Antarctic transmission by an ice floe, Ocean Model., 96, 8592. LA and SK provided SAR spectra. production and air/ice/ocean/biogeochemistry interactions in the Ross Sea Geosci. Please note that many of the page functionalities won't work as expected without javascript enabled. All other systems are swell and are ranked based on their energy contents as primary, secondary, and tertiary swell. With a combination of ocean assimilation model output, objectively analyzed products, and atmospheric reanalysis, this paper investigates the mechanism of . Leg2 went across the Pacific Ocean to Punta Arenas, Chile, with stations at Mertz Glacier, Balleny Islands, Scott Island, Mount Siple (the southernmost station), Peter I Island, and Diego Ramrez. M.-H., Pujol, M.-I., Ballarotta, M., Durand, I., and Provost, C.: The marine radar forms images of the surrounding area based on the backscatter of radar beams. Lett., 41, 89188925, 2014.a, b, Rodrguez-Ros, P., Corts, P., Robinson, C.M., Nunes, S., Hassler, An approximation of R(f) for the Akademik Tryoshnikov was calculated solving the equation of motion with a model based on the boundary element method (NEMOH,Babarit and Delhommeau,2015) and taking into account the ship's heading, forward speed, and loading conditions. Rev. Only a handful of buoys have operated in the region: (i)the Southern Ocean Flux Station (Schulz etal.,2011, 2012), a meteorological buoy first deployed in 2010 at approximately 350nautical miles south-west of Tasmania (Australia) that provides observations of meteorological parameters, including the directional wave spectrum, downwelling radiation, and seawater temperature and salinity; (ii)the Southern Ocean wave buoy network, which is comprised of one directional wave buoy deployed south of Campbell Island (New Zealand) and five drifting buoys (Barbariol etal.,2019); and (iii)the Global Southern Ocean Array and the Global Argentine Basin Array, which are networks of fixed and moored platforms and mobile profilers (gliders) deployed south-west of Chile and in the Argentinian basin, respectively, to monitor waves, airsea fluxes of heat, moisture and momentum, and physical, biological, and chemical properties throughout the water column (Trowbridge etal.,2019). Leg1 was along the Indian Ocean from Cape Town, South Africa, to Hobart, Australia, with stops at Marion Island, Iles de Crozet et Kerguelen, and Heard Island. wind-generated ocean waves, Philos. Wind measurements were acquired at a rate of 1Hz, averaged over 175s and converted from the measurement height to a neutral 10m wind speed (U10) by assuming a logarithmic profile (seeHolthuijsen,2007) before being passed on to the WaMoS-II. Calibrated A and B coefficients were subsequently used to re-scale individual modes of the energy spectrum. The latter, however, does not coincide with the wave energy spectrum, because it represents the intensity of the radar backscatter rather than the amplitude of the water surface elevation (NietoBorge etal.,1999; Hessner etal.,2002). This is achieved with the linear regression equation (seeNietoBorge etal.,1999, 2004). How the Antarctic Circumpolar Current helps keep Antarctica frozen Chem. The ACC. Offshore and Polar Engineering Conference (ISOPE), International Society of Lett., 102, We remark that SAR detects wavelength longer than 115m (approximately, wave periods exceeding 8s or frequencies below 0.1Hz) and represented swell systems primarily. 1. Trowbridge, J., Weller, R., Kelley, D., Dever, E., Plueddemann, A., Barth, This system of currents, known as the Atlantic Meridional Overturning Circulation, or AMOC, moves 15 million cubic meters of water per second. Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, College of Marine Sciences, Shanghai Ocean University, 999 Huchenghuan Road, Lingang New City, Shanghai 201306, China, International Research Center for Marine Biosciences (Ministry of Science and Technology), Shanghai Ocean University, Shanghai 201306, China, Shanghai Engineering Research Center of Hadal Science & Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China, Key Laboratory of Protection and Utilization of Marine Resources, Guangxi Minzu University, Nanning 530007, China. ocean waves, Geophys. Atmosphere-Basel, 11, 556, https://doi.org/10.3390/atmos11060556, 2020.a, b, Schmale, J., Baccarini, A., Thurnherr, I., Henning, S., Efraim, A., Regayre, L., Bolas, C., Hartmann, M., Welti, A., Lehtipalo, K., Aemisegger, F., Antarctic circumpolar current's role in the Antarctic ice system: An The instrument uses the marine X-band radar (9.41GHz) a standard equipment on any vessels to acquire high-definition radar images of the surrounding ocean surface and derive the directional wave energy spectrum, related integral parameters such as the significant wave height and mean wave period, and surface current speed and direction. The Antarctic Circumpolar Current - Miami Soc., 100, 22602283, https://doi.org/10.1175/BAMS-D-18-0187.1, 2019.a, b, c, d, e, f, Schulz, E., Grosenbaugh, M.A., Pender, L., Greenslade, D., and Trull, T.W.: It is vital for. Further, Ekman components remain uncertain in the Southern Ocean due to inaccuracies in estimating wind stress from the atmospheric system, adding inconsistencies to benchmark statistics. Alberello, A., Bennetts, L., and Toffoli, A.: Antarctic Circumnavigation An area bigger than Mexico has failed to freeze, worrying scientists. It does not resolve the wind sea, i.e.the short-wave components directly generated by local winds. It is driven by strong westerly winds and creates some of the roughest seas in the world that are notorious to sailors. Lett., 37, L05603, https://doi.org/10.1029/2009GL041771, 2010.a, b, Toffoli, A., McConochie, J., Ghantous, M., Loffredo, L., and Babanin, A.V.: In Sects.2 and3, details of the expedition, the instrumentation, and its calibration are presented. The most substantial positive biases are reported in the marginal ice zone, where Antarctic sea ice affects wind speed detection. Both current speed and direction can be quantified by minimising the distance between the position of the spectral energy in I(3)(kx,ky,) and the theoretical position given by Eq.(1) using least-squares techniques (Young etal.,1985). Rogue Waves in an Annular Wave Flume, Phys. formation of extreme events, Phys. Explaining the Zonal Asymmetry in the AirSea Net Heat Flux Climatology (2002), Hessner etal. methods, instructions or products referred to in the content. Martnez-Garca, A., Stirnimann, L., Roychoudhury, A., Haug, G.H., and Sigman, D.M.: The Nitrogen Isotopic Composition of Tissue and This limitation is partly addressed by the recently launched Chinese-French Oceanography Satellite (CFOSAT) mission, which detects wave systems with wavelengths longer than 70m (Hauser etal.,2020; Aouf etal.,2020). Although there have been many expeditions crossing the Southern Ocean (see a general overview inSchmale etal.,2019), measurements have primarily been taken en route to Antarctic stations, leaving entire sectors undersampled. Mooring design using wave-state estimate from the Southern Ocean, J. Scientists have long seen the Atlantic Meridional Overturning Circulation, or AMOC, as one of the planets most vulnerable tipping elements meaning the system could undergo an abrupt and irreversible change, with dramatic consequences for the rest of the globe. The basic input for extracting sea state features is a sequence of 64 consecutive images, which correspond to a time period of 175s (one complete image is acquired for every full turn of the antenna). articles published under an open access Creative Common CC BY license, any part of the article may be reused without Day and time of available measurements can be found in the file Available_Measurements_List.txt, which is included in Alberello etal. Elsnab, J., and Monty, J.P.: Sea ice floes dissipate the energy of steep As a benchmark, collocated values of P50, their interquartile range (IQR), and P90 are reported in the figure. Thurnherr, I., Kozachek, A., Graf, P., Weng, Y., Bolshiyanov, D., Landwehr, S., Pfahl, S., Schmale, J., Sodemann, H., Steen-Larsen, H. C., Toffoli, A., Wernli, H., and Aemisegger, F.: Meridional and vertical variations of the water vapour isotopic composition in the marine boundary layer over the Atlantic and Southern Ocean, Atmos. The Antarctic Circumpolar Current (ACC), the only ocean current that circumnavigates the planet, is speeding up. Dynamics of Pacific Antarctic Circumpolar Current (DYNAPACC) Knowledge about human impacts on these two extreme environments is limited. technique for the retrieval of near-surface vertical current shear from Interestingly, observations were notably higher than P90 for the majority of the expedition. The shift would be as abrupt and irreversible as turning off a light switch, and it could lead to dramatic changes in weather on either side of the Atlantic. AMSR-E 89-GHz channels, J. Geophys. T. R. Soc. Montiel, F., Squire, V.A., and Bennetts, L.G.: Attenuation and directional High-frequency components (f>0.1Hz) are not resolved in SAR but appear in the WaMoS-II spectra. Expedition (ACE) 20th December 201619th March 2017, Zenodo, Young, I.R. and Ribal, A.: Multiplatform evaluation of global trends in wind Geosci. Lett., 118, 144503, Treguier, A.-M. and Klein, P.: Instability of wind-forced inertial There are also low wind speeds (U10<3ms1 for both P50 and P90) in the lee of the Antarctic Peninsula, although this may relate to uncertainties due to a high concentration of sea ice (see Fig.1) and/or the increased drag over sea ice compared to open water (Martinson and Wamser,1990). Here, we analyzed the metal accumulations of two amphipod species, Eurythenes gryllus, from the Mariana Trench (6040 m, 11.36N, 142.41E) in the West Pacific Ocean, and Pseudorchomene plebs, from the Ross Sea (600 m, 77.12 S, 167,67 E) in . Martinson, D.G. and Wamser, C.: Ice drift and momentum exchange in winter Both the wave spectra and wind direction follow the coming from convention. In its standard output format, WaMoS-II archives the wave spectrum as a function of wave frequency, f=/2, and direction, E(f,); the change in variables from wave numbers to frequencydirection satisfies the dispersion relation in Eq.(1). The reference values were reconstructed from records of ship motion, which were measured throughout the expedition with an inertial measurement unit (IMU) at a sampling rate of 1Hz (Alberello etal.,2020b; Landwehr etal.,2021). 84668486, 2015b., Lundy, D.: Godforsaken sea: racing the world's most dangerous waters, Vintage These include, but are not limited to, airsea fluxes (mass, gas, heat, and momentum), aerosol concentrations, stable water isotopologues, and micro-fibres. This deep mixed layer gives the Southern Ocean capacity to store more heat and gases than any other latitude band on the planet, making this remote ocean a major driver of the Earth's climate system (see, for example,Dong etal.,2007). The geographical distributions of current speeds, directions, and concurrent differences between WaMoS-II and altimeter sensors are presented in Fig.12. Nevertheless, there is a notable RMSE3.2ms1, with R0.70 and SI0.360. The largest waves (Hs>6m) were encountered at the beginning of Leg2 (see photos of the sea state in Fig.2a and b). interaction-induced vertical mixing and its effects in ocean and climate Ocean. of the 11th European Wave and Tidal Energy Conference (EWTEC2015), September2015, Nantes, France, ID: hal-01198800, 2015.. Figure2Examples of sea state conditions: ocean surface during storm conditions (a), sailing through a storm (b), and the marginal ice zone (c). Radar imaging effects like tilt modulation, which refers to changes in the effective incidence angle along the long-wave slope, and shadowing, which is caused by the highest waves in the image, contribute to an inaccurate form of the resulting spectral density function, shifting energy towards high wave numbers (NietoBorge etal.,2004). The inverse wave age is the ratio of wind speed to wave phase velocity (i.e.the ratio of wavelength to period). directional ocean waves: the role of the modulational instability in the Park et al. Significant wave height Hs follows the wind pattern, underpinning the dominance of wind seas on swell systems. E, 102, 013106, Hanson, J.L. and Phillips, O.M.: Automated analysis of ocean surface measurements in Europe: applications of WaMoS II as a sensor for sea state, Since there are no landmasses blocking its way, the West Wind Drift drives the water unhindered eastwards around. https://doi.org/10.1016/j.ocemod.2015.03.001, 2015.a, Bennetts, L. G., O'Farrell, S., and Uotila, P.: Brief communication: Impacts of ocean-wave-induced breakup of Antarctic sea ice via thermodynamics in a stand-alone version of the CICE sea-ice model, The Cryosphere, 11, 10351040, https://doi.org/10.5194/tc-11-1035-2017, 2017.a, Collard, F., Ardhuin, F., and Chapron, B.: Monitoring and analysis of ocean Toffoli, A.: Fourier amplitude distribution and intermittency in mechanically generated surface gravity waves, Phys. https://doi.org/10.1103/PhysRevLett.118.144503, 2017.a, b, Treguier, A.-M. and Klein, P.: Instability of wind-forced inertial See further details. Output files consist of (i)the directional wave energy spectrum in the wave number domain (E(kx,ky), file extension D2S) and frequencydirectional domain (E(f,), file extension FTH) and (ii)the (single) one-dimensional frequencyenergy spectrum S(f) obtained by integrating the directional spectrum E(f,) over (file extension D1S). Onorato, M., Saunders, C., Skatulla, S., and Toffoli, A.: Effects of an a measure of average wave height that is defined as Hs=4m0. 3, Australian Antarctic Data Centre, https://doi.org/10.26179/5ed0a30aaf764, Metal Accumulations in Two Extreme-Environment Amphipods, Hadal Eurythenes gryllus and Antarctic Pseudorchomene plebs. Change, 3, 509526. turbulence and intermittency in wave-induced oscillatory flows, Wave Motion, 84, 8189, 2019b.. Res. A, 315, 509562, 1985., Dong, S., Gille, S.T., and Sprintall, J.: An assessment of the Southern Ocean mixed layer heat budget, J. Climate change is making one of the world's strongest currents flow Above all, intense winds give rise to some of the fiercest waves on the planet (e.gBarbariol etal.,2019; Vichi etal.,2019; Young and Ribal,2019; Young etal.,2020). Disclaimer/Publishers Note: The statements, opinions and data contained in all publications are solely Driven at least in part by the vigorous mid-latitude westerly winds, the ACC is . In recent years, researchers have suggested that . 1985., Young, I.R., Fontaine, E., Liu, Q., and Babanin, A.V.: The Wave Climate of Nevertheless, sea state observations are scattered in both space and time due to the nature of polar satellite orbits, and normally limited to average wind and current speeds, and wave heights. Stansberg, C., Tamura, H., and Trulsen, K.: Statistical properties of Scientists have also analyzed multiple proxy indicators of the currents strength, including microscopic organisms and tiny sediments from the seafloor, to show the system is in its weakest state in more than 1,000 years. The strong ACC continually connects. tropical cyclones: Field observations on the Australian North-West Shelf, J. Geophys. Alberello, A., Bennetts, L., Toffoli, A., and Derkani, M.: Antarctic interesting to readers, or important in the respective research area. [1] High resolution hydrographic sections and maps of the gradient of sea surface height (SSH) reveal that the Antarctic Circumpolar Current (ACC) consists of multiple jets or frontal filaments. II, 131, 16, Melville, W.K.: The role of surface-wave breaking in air-sea interaction, Records were acquired underway during the Antarctic Circumnavigation Expedition (ACE), which went around the Southern Ocean from December2016 to March2017 (Austral summer).