Abstract
Interannual variations of the eddy kinetic energy (EKE) related to two types of winter circulation events (“O” and “U”) were investigated based on the outputs of the Ocean General Circulation Model (OGCM) for the Earth Simulator (OFES) and the corresponding energetic analyses. Results show that the EKE is strong and extends eastward to offshore the Vietnam coast about 2°, associated with the weaker South China Sea western boundary current (SCSwbc) in “O” type years, while the EKE is weak and high value that can be attained is narrowed along the coast, associated with the stronger SCSwbc in “U” type years. The energy budget shows that the wind stress and barotropic/baroclinic instability are important factors to regulate the EKE in “U” and “O” years. For “U” years, under a strong winter monsoon forcing, the SCSwbc strengthen, the directly wind work and barotropic conversion from the mean kinetic energy (MKE) to EKE are weak, thus the EKE decrease corresponding to the baroclinic conversion from the kinetic energy to potential energy. However, the situation is reversed in “O” years. Under the influence of El Niño events, wind stress forces can weaken SCSwbc and enhance EKE in pattern “O”, whereas La Niña events have relatively weaker influences. The barotropic conversion rate in “O” type is nearly eight times of the “U” type. The pressure work and advection term are the main sources to greatly suppress EKE in the SCSwbc region.
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Cai Z Y, Gan J P. 2021. Dynamics of the layered circulation inferred from kinetic energy pathway in the South China Sea. Journal of Physical Oceanography, 51(5): 1671–1685, https://doi.org/10.1175/JPO-D-20-0226.1.
Chelton D B, Schlax M G, Samelson R M et al. 2011. Global observations of nonlinear mesoscale eddies. Progress in Oceanography, 91(2): 167–216, https://doi.org/10.1016/j.pocean.201L01.002.
Chen C L, Wang G H. 2014. Interannual variability of the eastward current in the western South China Sea associated with the summer Asian monsoon. Journal of Geophysical Research: Oceans, 119(9): 5745–5754, https://doi.org/10.1002/2014JC010309.
Chen G X, Hou Y J, Chu X Q et al. 2009. The variability of eddy kinetic energy in the South China Sea deduced from satellite altimeter data. Chinese Journal of Oceanology and Limnology, 27(4): 943–954, https://doi.org/10.1007/s00343-009-9297-6.
Chen G X, Hou Y J, Chu X Q. 2011. Mesoscale eddies in the South China Sea: mean properties, spatiotemporal variability, and impact on thermohaline structure. Journal of Geophysical Research: Oceans, 116(C6): C06018, https://doi.org/10.1029/2010jc006716.
Chen G X, Hou Y J, Zhang Q L et al. 2010. The eddy pair off eastern Vietnam: interannual variability and impact on thermohaline structure. Continental Shelf Research, 30(7): 715–723, https://doi.org/10.1016/j.csr.2009.11.013.
Chen G X, Wang D X, Dong C M et al. 2015. Observed deep energetic eddies by seamount wake. Scientific Reports, 5(1): 17416, https://doi.org/10.1038/srep17416.
Chen G X, Xue H J. 2014. Westward intensification in marginal seas. Ocean Dynamics, 64(3): 337–345, https://doi.org/10.1007/s10236-014-0691-z.
Cheng X H, Qi Y Q. 2010. Variations of eddy kinetic energy in the South China Sea. Journal of Oceanography, 66(1): 85–94, https://doi.org/10.1007/s10872-010-0007-y.
Chu X Q, Chen G X, Qi Y Q. 2020. Periodic mesoscale eddies in the South China Sea. Journal of Geophysical Research: Oceans, 125(1): e2019JC015139, https://doi.org/10.1029/2019JC015139.
Chu X Q, Dong C M, Qi Y Q. 2017. The influence of ENSO on an oceanic eddy pair in the South China Sea. Journal of Geophysical Research: Oceans, 122(3): 1643–1652, https://doi.org/10.1002/2016jc012642.
Chu X Q, Xue H J, Qi Y Q et al. 2014. An exceptional anticyclonic eddy in the South China Sea in 2010. Journal of Geophysical Research: Oceans, 119(2): 881–897, https://doi.org/10.1002/2013JC009314.
Dale W. 1956. Wind and drift current in the South China Sea. The Malayan Journal of Tropical Geography, 8: 1–31.
Dong C M, McWilliams J C, Liu Y et al. 2014. Global heat and salt transports by eddy movement. Nature Communications, 5(1): 3294, https://doi.org/10.1038/ncomms4294.
Ducet N, Le Traon P Y. 2001. A comparison of surface eddy kinetic energy and Reynolds stresses in the Gulf Stream and the Kuroshio Current systems from merged TOPEX/Poseidon and ERS-1/2 altimetric data. Journal of Geophysical Research: Oceans, 106(C8): 16603–16622, https://doi.org/10.1029/2000JC000205.
Fang G H, Wang G, Fang Y et al. 2012. A review on the South China Sea western boundary current. Acta Oceanologica Sinica, 31(5): 1–10, https://doi.org/10.1007/s13131-012-0231-y.
Fang W D, Fang G H, Shi P et al. 2002. Seasonal structures of upper layer circulation in the southern South China Sea from in situ observations. Journal of Geophysical Research: Oceans, 107(C11): 3202, https://doi.org/10.1029/2002JC001343.
Feng B X, Liu H L, Lin P F et al. 2017. Meso-scale eddy in the South China Sea simulated by an eddy-resolving ocean model. Acta Oceanologica Sinica, 36(5): 9–25, https://doi.org/10.1007/s13131-017-1058-3.
Feng B X, Liu H L, Lin P F. 2020. Effects of Kuroshio intrusion optimization on the simulation of mesoscale eddies in the northern South China Sea. Acta Oceanologica Sinica, 39(3): 12–24, https://doi.org/10.1007/s13131-020-1565-5.
Feng M, Wijffels S, Godfrey S et al. 2005. Do eddies play a role in the momentum balance of the Leeuwin Current? Journal of Physical Oceanography, 35(6): 964–975, https://doi.org/10.1175/JPO2730.1.
Frenger I, Gruber N, Knutti R et al. 2013. Imprint of Southern Ocean eddies on winds, clouds and rainfall. Nature Geoscience, 6(8): 608–612, https://doi.org/10.1038/ngeo1863.
Gan J P, Li H, Curchitser E N et al. 2006. Modeling South China Sea circulation: response to seasonal forcing regimes. Journal of Geophysical Research: Oceans, 111(C6): C06034, https://doi.org/10.1029/2005JC003298.
Gan J P, Qu T D. 2008. Coastal jet separation and associated flow variability in the southwest South China Sea. Deep Sea Research Part I: Oceanographic Research Papers, 55(1): 1–19, https://doi.org/10.1016/j.dsr.2007.09.008.
Geng W, Xie Q, Chen G X et al. 2016. Numerical study on the eddy-mean flow interaction between a cyclonic eddy and Kuroshio. Journal of Oceanography, 72(5): 727–745, https://doi.org/10.1007/s10872-016-0366-0.
Guo Z X, Yang T H, Qiu D Z. 1985. The South China Sea Warm current and the SW-ward current on its right side in winter. Tropic Oceanology, 4(1): 1–9. (in Chinese with English abstract)
He Q Y, Zhan H G, Cai S Q et al. 2018. A new assessment of mesoscale eddies in the South China Sea: surface features, three-dimensional structures, and thermohaline transports. Journal of Geophysical Research: Oceans, 123(7): 4906–4929, https://doi.org/10.1029/2018JC014054.
He Q Y, Zhan H G, Xu J et al. 2019. Eddy-induced chlorophyll anomalies in the western South China Sea. Journal of Geophysical Research: Oceans, 124(12): 9487–9506, https://doi.org/10.1029/2019JC015371.
He Z G, Wang D X. 2009. Surface pattern of the South China Sea western boundary current in winter. In: Gan, J ed. Advances in Geosciences. World Scientific Publishing Co Pte Ltd., 128 Farred RD, Singapore. Volume 12: Ocean Science. p.99–107, https://doi.org/10.1142/9789812836168_0008.
Ho C R, Kuo N J, Zheng Q A et al. 2000. Dynamically active areas in the South China Sea detected from TOPEX/Poseidon satellite altimeter data. Remote Sensing of Environment, 71(3): 320–328, https://doi.org/10.1016/S0034-4257(99)00094-2.
Holloway G. 1986. Estimation of oceanic eddy transports from satellite altimetry. Nature, 323(6085): 243–244, https://doi.org/10.1038/323243a0.
Hu J Y, Kawamura H, Hong H S et al. 2000. A review on the currents in the South China Sea: seasonal circulation, South China Sea Warm current and Kuroshio Intrusion. Journal of Oceanography, 56(6): 607–624, https://doi.org/10.1023/A:1011117531252.
Hu J Y, Zheng Q A, Sun Z Y et al. 2012. Penetration of nonlinear Rossby eddies into South China Sea evidenced by cruise data. Journal of Geophysical Research: Oceans, 117(C3): C03010, https://doi.org/10.1029/2011jc007525.
Hu S J, Sprintall J, Guan C et al. 2020. Deep-reaching acceleration of global mean ocean circulation over the past two decades. Science Advances, 6(6): eaax7727, https://doi.org/10.1126/sciadv.aax7727.
Hurlburt H E, Metzger E J, Hogan P J et al. 2008. Steering of upper ocean currents and fronts by the topographically constrained abyssal circulation. Dynamics of Atmospheres and Oceans, 45(3–4): 102–134, https://doi.org/10.1016/j.dynatmoce.2008.06.003.
Hwang C, Chen S A. 2000. Circulations and eddies over the South China Sea derived from TOPEX/Poseidon altimetry. Journal of Geophysical Research: Oceans, 105(C10): 23943–23965, https://doi.org/10.1029/2000JC900092.
Ivchenko V O, Treguier A M, Best S E. 1997. A kinetic energy budget and internal instabilities in the Fine Resolution Antarctic Model. Journal of Physical Oceanography, 27(1): 5–22, https://doi.org/10.1175/1520-0485(1997)027<0005:AKEBAI>2.0.CO;2.
Kang D J, Curchitser E N. 2015. Energetics of Eddy-mean flow interactions in the gulf stream region. Journal of Physical Oceanography, 45(4): 1103–1120, https://doi.org/10.1175/JPO-D-14-0200.1.
Kubryakov A A, Kozlov I E, Manucharyan G E. 2021. Large mesoscale eddies in the Western Arctic Ocean from satellite altimetry measurements. Journal of Geophysical Research: Oceans, 126(5): e2020JC016670, https://doi.org/10.1029/2020JC016670.
Li H, Wang Q, Huang K et al. 2017. Characteristics of eddy-mean flow interaction in the offshore current area of western South China Sea. Oceanologia et Limnologia Sinica, 48(5): 912–925, https://doi.org/10.11693/hyhz20170400086. (in Chinese with English abstract)
Li Y L, Han W Q, Wilkin J L et al. 2014. Interannual variability of the surface summertime eastward jet in the South China Sea. Journal of Geophysical Research: Oceans, 119(10): 7205–7228, https://doi.org/10.1002/2014JC010206.
Lin P F, Wang F, Chen Y L et al. 2007. Temporal and spatial variation characteristics on eddies in the South China Sea I. Statistical analyses. Acta Oceanologica Sinica, 29(3): 14–22, https://doi.org/10.3321/j.issn:0253-4193.2007.03.002. (in Chinese with English abstract)
Liu Q Y, Feng M, Wang D X. 2011. ENSO-induced interannual variability in the southeastern South China Sea. Journal of Oceanography, 67(1): 127–133, https://doi.org/10.1007/s10872-011-0002-y.
Liu Q Y, Huang R X, Wang D X. 2012. Implication of the South China Sea throughflow for the interannual variability of the regional upper-ocean heat content. Advances in Atmospheric Sciences, 29(1): 54–62, https://doi.org/10.1007/s00376-011-0068-x.
Liu Q Y, Jia Y L, Liu P H et al. 2001. Seasonal and intraseasonal thermocline variability in the central South China Sea. Geophysical Research Letters, 28(23): 4467–4470, https://doi.org/10.1029/2001GL013185.
Lyu K W, Yang X Y, Zheng Q A et al. 2016. Intraseasonal variability of the winter western boundary current in the South China Sea using satellite data and mooring observations. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 9(11): 5079–5088, https://doi.org/10.1109/JSTARS.2016.2553049.
Ma X H, Jing Z, Chang P et al. 2016. Western boundary currents regulated by interaction between ocean eddies and the atmosphere. Nature, 535(7613): 533–537, https://doi.org/10.1038/nature18640.
McGillicuddy D JJr, Anderson L A, Bates N R et al. 2007. Eddy/wind interactions stimulate extraordinary mid-ocean plankton blooms. Science, 316(5827): 1021–1026, https://doi.org/10.1126/science.1136256.
Metzger E J, Hurlburt H E. 2001. The nondeterministic nature of Kuroshio penetration and eddy shedding in the South China Sea. Journal of Physical Oceanography, 31(7): 1712–1732, https://doi.org/10.1175/1520-0485(2001)031<1712:Tnnokp>2.0.Co;2.
Ni Q B, Zhai X M, Wang G H et al. 2020. Widespread mesoscale dipoles in the global ocean. Journal of Geophysical Research: Oceans, 125(10): e2020JC016479, https://doi.org/10.1029/2020JC016479.
Qiu B, Chen S M, Schneider N, 2014. A coupled decadal prediction of the dynamic state of the Kuroshio extension system. Journal of Climate, 27(4): 1751–1764, https://doi.org/10.1175/JCLI-D-13-00318.1.
Qu T D, Du Y, Sasaki H. 2006. South China Sea throughflow: a heat and freshwater conveyor. Geophysical Research Letters, 33(23): L23617, https://doi.org/10.1029/2006GL028350.
Quan Q, Xue H J, Qin H L et al. 2016. Features and variability of the South China Sea western boundary current from 1992 to 2011. Ocean Dynamics, 66(6): 795–810, https://doi.org/10.1007/s10236-016-0951-1.
Sasaki H, Nonaka M, Masumoto Y et al. 2008. An eddy-resolving hindcast simulation of the quasiglobal ocean from 1950 to 2003 on the Earth Simulator. In: Hamilton K, Ohfuchi W eds. High Resolution Numerical Modelling of the Atmosphere and Ocean. Springer, New York. p.157–185, https://doi.org/10.1007/978-0-387-49791-4_10.
Sasaki H, Sasai Y, Kawahara S et al. 2004. A series of eddy-resolving ocean simulations in the world ocean-OFES (OGCM for the Earth Simulator) project. In: Oceans’ 04 MTS/IEEE Techno-Ocean’04 (IEEECat. No.04CH37600). IEEE, Kobe. p.1535–1541, https://doi.org/10.1109/OCEANS.2004.1406350.
Shaw P T, Chao S Y, Fu L L. 1999. Sea surface height variations in the South China Sea from satellite altimetry. Oceanologica Acta, 22(1): 1–17, https://doi.org/10.1016/S0399-1784(99)80028-0.
Shu Y Q, Xue H J, Wang D X et al. 2016. Observed evidence of the anomalous South China Sea western boundary current during the summers of 2010 and 2011. Journal of Geophysical Research: Oceans, 121(2): 1145–1159, https://doi.org/10.1002/2015JC011434.
Su J Z, Lu J, Hou Y J et al. 2002. Analysis of satellite-tracked drifting buoys in the South China Sea. Oceanologia et Limnologia Sinica, 33(2): 121–127, https://doi.org/10.3321/j.issn:0029-814X.2002.02.002. (in Chinese with English abstract)
Su J L, Xu J P, Cai S Q et al. 1999. Gyres and eddies in the South China Sea. In: Ding Y H, Li C Y eds. Onset and Evolution of the South China Sea Monsoon and its Interaction with the Ocean. Beijing Meteorological Press, Beijing, China. p.272–279.
Sun W J, Dong C M, Wang R Y et al. 2017. Vertical structure anomalies of oceanic eddies in the Kuroshio Extension region. Journal of Geophysical Research: Oceans, 122(2): 1476–1496, https://doi.org/10.1002/2016JC01222.
Sun Y, Lan J. 2021. Summertime eastward jet and its relationship with western boundary current in the South China Sea on the interannual scale. Climate Dynamics, 56(3): 935–947, https://doi.org/10.1007/s00382-020-05511-z.
Sun Z B, Zhang Z W, Zhao W et al. 2016. Interannual modulation of eddy kinetic energy in the northeastern South China Sea as revealed by an eddy-resolving OGCM. Journal of Geophysical Research: Oceans, 121(5): 3190–3201, https://doi.org/10.1002/2015JC011497.
Tuo P F, Yu J Y, Hu J Y. 2019. The changing influences of ENSO and the Pacific meridional mode on mesoscale eddies in the South China Sea. Journal of Climate, 32(3): 685–700, https://doi.org/10.1175/JCLI-D-18-0187.1.
Wang C Z, Wang W Q, Wang D X et al. 2006a. Interannual variability of the South China Sea associated with El Niño. Journal of Geophysical Research: Ocean, 111(C3): C03023, https://doi.org/10.1029/2005JC003333.
Wang D X, Liu Q Y, Huang R X et al. 2006b. Interannual variability of the South China Sea throughflow inferred from wind data and an ocean data assimilation product. Geophysical Research Letters, 33(14): L14605, https://doi.org/10.1029/2006GL026316.
Wang D X, Liu Q Y, Xie Q et al. 2013a. Progress of regional oceanography study associated with western boundary current in the South China Sea. Chinese Science Bulletin, 58(11): 1205–1215, https://doi.org/10.1007/s11434-012-5663-4.
Wang D X, Wang Q, Zhou W D et al. 2013b. An analysis of the current deflection around Dongsha Islands in the northern South China Sea. Journal of Geophysical Research: Oceans, 118(1): 490–501, https://doi.org/10.1029/2012JC008429.
Wang D X, Xiao J G, Shu Y Q et al. 2016. Progress on deep circulation and meridional overturning circulation in the South China Sea. Science China Earth Sciences, 59(9): 1827–1833, https://doi.org/10.1007/s11430-016-5324-6.
Wang D X, Xu H Z, Lin J et al. 2008a. Anticyclonic eddies in the northeastern South China Sea during winter 2003/2004. Journal of Oceanography, 64(6): 925–935, https://doi.org/10.1007/s10872-008-0076-3.
Wang G H, Chen D K, Su J L. 2008b. Winter eddy genesis in the eastern South China Sea due to orographic wind jets. Journal of Physical Oceanography, 38(3): 726–732, https://doi.org/10.1175/2007jpo3868.1.
Wang G H, Su J L, Chu P C. 2003. Mesoscale eddies in the South China Sea observed with altimeter data. Geophysical Research Letters, 30(21): 2121, https://doi.org/10.1029/2003GL018532.
Wang L P, Koblinsky C J, Howden S. 2000. Mesoscale variability in the South China Sea from the TOPEX/Poseidon altimetry data. Deep Sea Research Part I: Oceanographic Research Papers, 47(4): 681–708, https://doi.org/10.1016/S0967-0637(99)00068-0.
Wang Q, Zeng L L, Shu Y Q et al. 2019. Energetic topographic Rossby waves in the northern South China Sea. Journal of Physical Oceanography, 49(10): 2697–2714, https://doi.org/10.1175/JPO-D-18-0247.1.
Wang Q, Zeng L L, Shu Y Q et al. 2020. Interannual variability of South China Sea winter circulation: response to Luzon Strait transport and El Niño wind. Climate Dynamics, 54(1–2): 1145–1159, https://doi.org/10.1007/s00382-019-05050-2.
Wyrtki K. 1961. Physical Oceanography of the Southeast Asian Waters. Scripps Institution of Oceanography, University of California, La Jolla. p.1–195.
Xie S P, Xie Q, Wang D X et al. 2003. Summer upwelling in the South China Sea and its role in regional climate variations. Journal of Geophysical Research: Oceans, 108(C8): 3261, https://doi.org/10.1029/2003JC001867.
Xiu P, Chai F, Shi L et al. 2010. A census of eddy activities in the South China Sea during 1993–2007. Journal of Geophysical Research: Oceans, 115(C3): C03012, https://doi.org/10.1029/2009JC005657.
Xue H J, Chai F, Pettigrew N et al. 2004. Kuroshio intrusion and the circulation in the South China Sea. Journal of Geophysical Research: Oceans, 109(C2): C02017, https://doi.org/10.1029/2002JC001724.
Yang H Y, Wu L X, Liu H L et al. 2013. Eddy energy sources and sinks in the South China Sea. Journal of Geophysical Research: Oceans, 118(9): 4716–4726, https://doi.org/10.1002/jgrc.20343.
Yao J L, Li H, Liu Q Y et al. 2017. Energy diagnostic of the mesoscale processes loaded by the South China Sea throughflow. Oceanologia et Limnologia Sinica, 48(6): 1257–1268, https://doi.org/10.11693/hyhz20170800207. (in Chinese with English abstract)
Yuan D L, Han W Q, Hu D X. 2007. Anti-cyclonic eddies northwest of Luzon in summer-fall observed by satellite altimeters. Geophysical Research Letters, 34(13): L13610, https://doi.org/10.1029/2007GL029401.
Zhang N N, Liu G Q, Liu Q Y et al. 2020. Spatiotemporal Variations of Mesoscale Eddies in the Southeast Indian Ocean. Journal of Geophysical Research: Oceans, 125(8): e2019JC015712, https://doi.org/10.1029/2019JC015712.
Zheng S J, Feng M, Du Y et al. 2018. Interannual variability of eddy kinetic energy in the subtropical southeast Indian Ocean associated with the El Niño-Southern Oscillation. Journal of Geophysical Research: Oceans, 123(2): 1048–1061, https://doi.org/10.1002/2017JC013562.
Zhou H, Yuan D L, Li R X et al. 2010. The western South China Sea currents from measurements by Argo profiling floats during October to December 2007. Chinese Journal of Oceanology and Limnology, 28(2): 398–406, https://doi.org/10.1007/s00343-010-9052-z.
Zhu X H, Zhao R X, Guo X Y et al. 2015. A long-term volume transport time series estimated by combining in situ observation and satellite altimeter data in the northern South China Sea. Journal of Oceanography, 71(6): 663–673, https://doi.org/10.1007/s10872-015-0305-5.
Zhuang W, Xie S P, Wang D X et al. 2010. Intraseasonal variability in sea surface height over the South China Sea. Journal of Geophysical Research: Oceans, 115(C4): C04010, https://doi.org/10.1029/2009JC005647.
Zu T T, Wang D X, Wang Q et al. 2020. A revisit of the interannual variation of the South China Sea upper layer circulation in summer: correlation between the eastward jet and northward branch. Climate Dynamics, 54(1–2): 457–471, https://doi.org/10.1007/s00382-019-05007-5.
Zu T T, Xue H J, Wang D X et al. 2019. Interannual variation of the South China Sea circulation during winter: intensified in the southern basin. Climate Dynamics, 52(3–4): 1917–1933, https://doi.org/10.1007/s00382-018-4230-3.
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Comments from two anonymous reviewers are greatly appreciated. The authors also appreciated the contributions of High Performance Computing Division and HPC managers Zhou WEI and Dandan SUI of the South China Sea Institute of Oceanology, Chinese Academy of Sciences.
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The providers of the data, including the AVISO data (cds.climate.copernicus.eu) and the OFES data (http://apdrc.soest.hawaii.edu/las_ofes/v6/dataset?catitem=2), are greatly appreciated.
Supported by the Science and Technology Basic Resources Investigation Program of China (No. 2017FY201402), the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) (No. GML 2019ZD0304), the National Key Research and Development Program of China (No. 2017YFC1404000), the National Natural Science Foundation of China (Nos. 41876017, 42176027, 41628601, 41706027, 41776014), the Guangzhou Science and Technology Plan Project (No. 202102080364), the Guangdong Basic and Applied Basic Research Foundation (No. 2022A1515011863), and the State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology Chinese Academy of Sciences (Nos. LTOZZ2101, LTOZZ2102)
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Li, W., Liu, Q., Fang, W. et al. Interannual variability of eddy kinetic energy in the South China Sea related to two types of winter circulation events. J. Ocean. Limnol. 41, 831–851 (2023). https://doi.org/10.1007/s00343-022-1237-8
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DOI: https://doi.org/10.1007/s00343-022-1237-8