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Ocean Current Dynamics and Renewable Energy from the Agulhas Current
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作者 Eckart Schumann Michael Roberts Mark Bodley 《Journal of Environmental & Earth Sciences》 2025年第4期232-245,共14页
The Agulhas Current is a major western boundary current flowing polewards on the southeast coast of South Africa.This analysis assesses its characteristics and suitability to generate power as a source of clean renewa... The Agulhas Current is a major western boundary current flowing polewards on the southeast coast of South Africa.This analysis assesses its characteristics and suitability to generate power as a source of clean renewable energy.On a section of coastline some 400 km long,over a period spanning more than 5 years an extensive set of current measurements was obtained.These data confirmed that south-westward currents with a speed greater than 1.2 m s^(-1)occurred over more than 60%of the recorded time;such ocean current speeds compare very favourably to winds required for energy generation.These currents occurred at the continental shelf break in water depths around 100 m,in the upper 50 m of the water column.Occasional current slowdowns and reversals did occur,with the major influence coming from‘Natal Pulses’,which are large-scale meanders in the Current that temporarily reversed the currents at the measurement sites.However,because of the surface temperature structure of the relevant water masses,such meanders can be identified in satellite imagery giving a few days advance warning of such current reversals.The characteristics of western boundary currents have been known for many years,but at Present,there is no operational system where this source of power is being utilised.It has tremendous potential for renewable energy generation,but is symptomatic of the many engineering challenges that still have to be solved to make such generation economically viable. 展开更多
关键词 5-Year Measurement Program Agulhas current Consistent currents>1.2 m s^(-1) South-East Coast of South Africa Water Depth 100 m
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Impacts of Ice-Ocean Stress on the Subpolar Southern Ocean:Role of the Ocean Surface Current
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作者 Yang WU Zhaomin WANG +1 位作者 Chengyan LIU Liangjun YAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期293-309,共17页
The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting t... The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting two simulations that include and exclude the OSC in the calculation of the ice-ocean stress(IOS), using an eddy-permitting coupled ocean-sea ice global model. By comparing the results of these two experiments, significant increases of 5%, 27%, and 24%, were found in the subpolar Southern Ocean when excluding the OSC in the IOS calculation for the ocean surface stress,upwelling, and downwelling, respectively. Excluding the OSC in the IOS calculation also visibly strengthens the total mechanical energy input to the OSC by about 16%, and increases the eddy kinetic energy and mean kinetic energy by about38% and 12%, respectively. Moreover, the response of the meridional overturning circulation in the Southern Ocean yields respective increases of about 16% and 15% for the upper and lower branches;and the subpolar gyres are also found to considerably intensify, by about 12%, 11%, and 11% in the Weddell Gyre, the Ross Gyre, and the Australian-Antarctic Gyre, respectively. The strengthened ocean circulations and Ekman pumping result in a warmer sea surface temperature(SST), and hence an incremental surface heat loss. The increased sea ice drift and warm SST lead to an expansion of the sea ice area and a reduction of sea ice volume. These results emphasize the importance of OSCs in the air-sea-ice interactions on the global ocean circulations and the mass balance of Antarctic ice shelves, and this component may become more significant as the rapid change of Antarctic sea ice. 展开更多
关键词 subpolar Southern ocean Antarctic sea ice ice-ocean stress air-sea-ice-ocean interaction ocean surface current MITgcm-ECCO2
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A multisource geomagnetic field model incorporating ocean circulation-induced magnetic field 被引量:5
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作者 HongBo Yao JuYuan Xu +2 位作者 Cong Yang ZhengYong Ren Keke Zhang 《Earth and Planetary Physics》 2025年第3期550-563,共14页
The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic... The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field model.Here,we present a method to account for the circulation-induced magnetic field during geomagnetic field modeling.First,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation model.Then,this forward model is subtracted from the observed data.Finally,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are co-estimated.Applying our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the data.Furthermore,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field model.The highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model. 展开更多
关键词 Macao Science Satellite-1(MSS-1) geomagnetic field modeling ocean tides ocean circulation
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Meridional Shift of Southern Ocean Mesoscale Eddies Since the 1990s 被引量:1
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作者 Fei SHI Qian SHI +5 位作者 Yiyong LUO Renhao WU Qinghua YANG Jiping LIU Jason YANG Jun SONG 《Advances in Atmospheric Sciences》 2025年第12期2529-2538,I0025-I0028,共14页
Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention ha... Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention has been paid to changes in the genesis locations of mesoscale eddies.Here,we provide evidence from three decades of satellite altimetry observations for the heterogeneity of the poleward shift of mesoscale activities,with the largest trend of~0.23°±0.05°(10 yr)^(-1) over the Atlantic sector and a moderate trend of~0.1°±0.03°(10 yr)^(-1) over the Indian sector,but no significant trend in the Pacific sector.The poleward shift of mesoscale eddies is associated with a southward shift of the local westerly winds while being constrained by the major topographies.As the poleward shift of westerly winds is projected to persist,the poleward oceanic heat flux from mesoscale eddies may influence future ice melt. 展开更多
关键词 mesoscale eddies Southern ocean poleward trend
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Revised global vertically integrated remanent magnetization model of the oceanic lithosphere with comparison to LCS-1 model and MSS-1 magnetic measurements 被引量:2
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作者 ShiDa Sun Hui Li +3 位作者 JinSong Du Pan Zhang Chao Chen PengFei Liu 《Earth and Planetary Physics》 2025年第3期653-666,共14页
The lithospheric magnetic field is an important component of the geomagnetic field,and the oceanic lithosphere exhibits distinct characteristics.Because of its formation mechanisms,evolutionary history,and geomagnetic... The lithospheric magnetic field is an important component of the geomagnetic field,and the oceanic lithosphere exhibits distinct characteristics.Because of its formation mechanisms,evolutionary history,and geomagnetic field polarity reversals,the oceanic lithosphere has significant remanent magnetization,which causes magnetic anomaly stripes parallel to the mid-ocean ridges.However,it is difficult to construct a high-resolution lithospheric magnetic field model in oceanic regions with relatively sparse data or no data.Using forward calculated lithospheric magnetic field data based on an oceanic remanent magnetization(ORM) model with physical and geological foundations as a supplement is a feasible approach.We first collect the latest available oceanic crust age grid,plate motion model,geomagnetic polarity timescale,and oceanic lithosphere thermal structure.Combining the assumptions that the paleo geomagnetic field is a geocentric axial dipole field and that the normal oceanic crust moves only in the horizontal direction,we construct a vertically integrated ORM model of the normal oceanic crust with a known age,including the intensity,inclination,and declination.Both the ORM model and the global induced magnetization(GIM) model are then scaled from two aspects between their forward calculated results and the lithospheric magnetic field model LCS-1.One aspect is the difference in their spherical harmonic power spectra,and the other is the misfit between the grid data over the oceans.We last compare the forward calculated lithospheric magnetic anomaly from the scaled ORM and GIM models with the Macao Science Satellite-1(MSS-1) observed data.The comparison results show that the magnetic anomalies over the normal oceanic crust regions at satellite altitude are mainly contributed by the high-intensity remanent magnetization corresponding to the Cretaceous magnetic quiet period.In these regions,the predicted and observed anomalies show good consistency in spatial distribution,whereas their amplitude differences vary across regions.This result suggests that regional ORM construction should be attempted in future work to address these amplitude discrepancies. 展开更多
关键词 oceanic remanent magnetization lithospheric magnetic field LCS-1 Macao Science Satellite-1
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Currents from relativistic laser-plasma interaction as a novel metrology for the system stability of high-repetition-rate laser secondary sources 被引量:1
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作者 Michael Ehret Iuliana-Mariana Vladisavlevici +16 位作者 Philip Wykeham Bradford Jakub Cikhardt Evgeny Filippov Jose Luis Henares Rubén Hernández Martín Diego de Luis JoséAntonio Pérez-Hernández Pablo Vicente Tomas Burian Enrique García-García Juan Hernández Cruz Mendez Marta Olivar Ruíz Óscar Varela Maria Dolores Rodríguez Frías João Jorge Santos Giancarlo Gatti 《Matter and Radiation at Extremes》 2025年第2期24-34,共11页
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second... This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers. 展开更多
关键词 relativistic laser plasma interaction pearson linear correlation proton spectrum cutoff energy interaction schemes ion acceleration target normal sheath accelerationthe return current return currents
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Integrated Equipment with Functions of Current Flow Control and Fault Isolation for Multiterminal DC Grids
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作者 Shuo Zhang Guibin Zou 《Energy Engineering》 EI 2025年第1期85-99,共15页
The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow ... The multi-terminal direct current(DC)grid has extinctive superiorities over the traditional alternating current system in integrating large-scale renewable energy.Both the DC circuit breaker(DCCB)and the current flow controller(CFC)are demanded to ensure the multiterminal DC grid to operates reliably and flexibly.However,since the CFC and the DCCB are all based on fully controlled semiconductor switches(e.g.,insulated gate bipolar transistor,integrated gate commutated thyristor,etc.),their separation configuration in the multiterminal DC grid will lead to unaffordable implementation costs and conduction power losses.To solve these problems,integrated equipment with both current flow control and fault isolation abilities is proposed,which shares the expensive and duplicated components of CFCs and DCCBs among adjacent lines.In addition,the complicated coordination control of CFCs and DCCBs can be avoided by adopting the integrated equipment in themultiterminal DC grid.In order to examine the current flow control and fault isolation abilities of the integrated equipment,the simulation model of a specific meshed four-terminal DC grid is constructed in the PSCAD/EMTDC software.Finally,the comparison between the integrated equipment and the separate solution is presented a specific result or conclusion needs to be added to the abstract. 展开更多
关键词 Integrated equipment multiterminal direct current grid current flow control fault isolation
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Ionospheric F-region currents estimated from Macao Science Satellite-1 and Swarm satellite magnetic data 被引量:1
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作者 JuYuan Xu HongBo Yao Keke Zhang 《Earth and Planetary Physics》 2025年第3期731-739,共9页
Accurate modeling of Earth's ionospheric F-region currents is essential for refining geomagnetic field models and understanding magnetosphere-ionosphere coupling.In this study,we develop averaged models to charact... Accurate modeling of Earth's ionospheric F-region currents is essential for refining geomagnetic field models and understanding magnetosphere-ionosphere coupling.In this study,we develop averaged models to characterize F-region currents using magnetic data from the MSS-1(Macao Science Satellite-1) and Swarm satellite missions.Our approach employs a toroidal field representation,utilizing spherical harmonics to capture spatial variations and Fourier series to represent temporal dynamics.Two models,Model-A and Model-B,derived from distinct datasets,are constructed to represent current patterns at altitudes of 450 km and 512 km,respectively.Our models successfully capture the primary spatial structures and seasonal variations of polar field-aligned currents.Additionally,they accurately reproduce the localized inter-hemispheric field-aligned currents observed in mid and low latitudes during solstices,particularly between 14:00 and 16:00 magnetic local times.These findings enhance our understanding of ionospheric F-region currents and contribute to more precise geomagnetic field modeling. 展开更多
关键词 Macao Science Satellite-1 SWARM field-aligned currents GEOMAGNETISM ionosphere
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The magnetic stripe signatures of the North Atlantic Ocean crust derived from Swarm and Macao Science Satellite-1 observations 被引量:1
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作者 PengFei Liu Liang Yin +1 位作者 ShiDa Sun HongBo Yao 《Earth and Planetary Physics》 2025年第3期635-641,共7页
The Earth's crust,the outer shell of the Earth,consists of continental crust and oceanic crust.Oceanic crust is created at the mid-oceanic ridge,where it is magnetized in the ambient field of the Earth.As new mate... The Earth's crust,the outer shell of the Earth,consists of continental crust and oceanic crust.Oceanic crust is created at the mid-oceanic ridge,where it is magnetized in the ambient field of the Earth.As new material is extruded,the crust spreads outward,retaining its magnetization.The reversal of the polarity of the Earth's magnetic field over geologic time leads to a pattern of striped magnetic anomalies.In this study,we carry out a preliminary evaluation on how data from the Macao Science Satellite-1(MSS-1),which has a low orbital inclination,influences inversion models of the oceanic crustal magnetic field when combined with data from the Swarm mission.For our modeling we use an equivalent source method based on a cubed-sphere grid.Our model captures the broad magnetic structure over the North Atlantic Ocean and demonstrates that the trend of magnetic stripes is consistent with the age frame of the oceanic crust.The amplitude of the radial magnetic field at 450 km the North Atlantic Ocean ranges from–11 nT to+8 nT.The addition of MSS-1 observations to Swarm data generates results consistent with the overall magnetic stripe pattern.The lack of short-wavelength scale structure reveals the limitation of high-altitude satellites in portraying fine features and hence lower-altitude observations would be required to delineate a more detailed crustal signature.It is expected to obtain a finer structure of oceanic magnetic stripes by combining low-altitude CHAMP field data and east-west gradient data derived from MSS-1 in future work. 展开更多
关键词 ocean magnetic stripes lithospheric magnetic structure Macao Science Satellite-1
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Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean
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作者 Tiantian Tang Jiaying He +1 位作者 Huihang Sun Jingjia Luo 《Atmospheric and Oceanic Science Letters》 2025年第1期24-31,共8页
A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 m.This study em... A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 m.This study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine heatwave.The sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep ocean.The latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging scheme.It excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the Blob.These improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean conditions.The results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms. 展开更多
关键词 Seasonal forecast ocean data assimilation Marine heatwave Subsurface temperature
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In situ constructing lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x) as bifunctional electrocatalyst for high-current-density water splitting 被引量:1
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作者 Yue Deng Jin Wang +6 位作者 Shao-Fei Zhang Zhi-Jia Zhang Jin-Feng Sun Tian-Tian Li Jian-Li Kang Hao Liu Shi Bai 《Rare Metals》 2025年第2期1053-1066,共14页
The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-... The stability and electrocatalytic efficiency of transition metal oxides for water splitting is determined by geometric and electronic structure,especially under high current densities.Herein,a newly designed lamella-heterostructured nanoporous CoFe/CoFe_(2)O_(4) and CeO_(2−x),in situ grown on nickel foam(NF),holds great promise as a high-efficient bifunctional electrocatalyst(named R-CoFe/Ce/NF)for water splitting.Experimental characterization verifies surface reconstruction from CoFe alloy/oxide to highly active CoFeOOH during in situ electrochemical polarization.By virtues of three-dimensional nanoporous architecture and abundant electroactive CoFeOOH/CeO_(2−x) heterostructure interfaces,the R-CoFe/Ce/NF electrode achieves low overpotentials for oxygen evolution(η_(10)=227 mV;η_(500)=450 mV)and hydrogen evolution(η_(10)=35 mV;η_(408)=560 mV)reactions with high normalized electrochemical active surface areas,respectively.Additionally,the alkaline full water splitting electrolyzer of R-CoFe/Ce/NF||R-CoFe/Ce/NF achieves a current density of 50 mA·cm^(−2) only at 1.75 V;the decline of activity is satisfactory after 100-h durability test at 300 mA·cm^(−2).Density functional theory also demonstrates that the electron can transfer from CeO_(2−x) by virtue of O atom to CoFeOOH at CoFeOOH/CeO_(2−x) heterointerfaces and enhancing the adsorption of reactant,thus optimizing electronic structure and Gibbs free energies for the improvement of the activity for water splitting. 展开更多
关键词 Lamellar nanoporous structure Electronic structure regulation High current density Theoretical calculation Overall water splitting
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Current development and prospect of national science and technology innovation platform in the railway industry 被引量:1
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作者 Fang Zhao Jinping Liu +3 位作者 Chunguang Zhang Zeping Zhao Xue Ning Junbiao Wang 《Railway Sciences》 2025年第2期266-279,共14页
Purpose–This study summarizes the overall situation of the resources of the national science and technology innovation platform in the railway industry,including the distribution of platform types,supporting institut... Purpose–This study summarizes the overall situation of the resources of the national science and technology innovation platform in the railway industry,including the distribution of platform types,supporting institutions,construction sites,professional fields,etc.,to provide a reference for the further improvement and optimization of the national science and technology innovation platform system in the railway industry.Design/methodology/approach–Through literature review,field investigation,expert consultation and other methods,this paper systematically investigates and analyzes the development status of the national science and technology innovation platform in the railway industry.Findings–Taking the national science and technology innovation platform of the railway industry as the research object,this paper investigates and analyzes the construction,development and distribution of the national science and technology innovation platform of railway industry over the years.And the National Engineering Research Center of High-speed Railway and Urban Rail Transit System Technology was taken as an example to introduce its operation effect.Originality/value–China Railway has made great development achievements,with the construction and development of national science and technology innovation platform in the railway industry.In recent years,a large number of national science and technology innovation platforms have been built in the railway industry,which play an important role in railway technological innovation,standard setting and commodification,and Railway Sciences provide strong support for railway technology development. 展开更多
关键词 Railway industry National science and technology innovation platform current development and prospect
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Seasonal variations of ocean-to-ice heat flux in north of the Fram Strait,Arctic Ocean
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作者 Yuang Liu Xiaoqiao Wang +1 位作者 Jinfeng Ding Lujun Zhang 《Acta Oceanologica Sinica》 2025年第3期71-83,共13页
As the Arctic undergoes rapid warming and sea ice continues to decline,Ocean-to-Ice Heat Flux(OIHF)plays a crucial role in regulating sea ice dynamics.This study investigates the seasonal variations in ocean-to-ice he... As the Arctic undergoes rapid warming and sea ice continues to decline,Ocean-to-Ice Heat Flux(OIHF)plays a crucial role in regulating sea ice dynamics.This study investigates the seasonal variations in ocean-to-ice heat flux in north of the Fram Strait using the regional Arctic Ocean/sea ice reanalysis product from 1991 to 2020.The analysis reveals that the OIHF exhibits significant seasonal variability,with a pronounced peak during winter in north of the Fram Strait,driven by inflows of Atlantic water.Warm Atlantic water intrusion begins in October,reaches its peak in January and February,and results in a delayed increase in OIHF,with maximum flux observed 2−3 months later.These results highlight the significant role of Atlantic water inflows in influencing Arctic sea ice dynamics and emphasize the need for further investigation into the coupled ocean-atmosphere processes that govern seasonal fluctuations in OIHF. 展开更多
关键词 Arctic ocean ocean-to-Ice Heat Flux(OIHF) North Atlantic current spatiotemporal variation
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Climate-relevant gases and their impact on the climate and environment of polar oceans
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作者 ZHAN Liyang YE Wangwang +7 位作者 YAN Jinpei ZHANG Miming LIU Jian TIAN Rong WANG Shanshan JIE Xiaomeng LI Yuhang WANG Wentao 《Advances in Polar Science》 2025年第1期5-17,共13页
Because of their effect on climate,carbon dioxide(CO_(2)),methane(CH_(4)),nitrous oxide(N_(2)O),and dimethylsulfide(DMS)are collectively designated as climate-relevant gases(CRGs).CO_(2),CH_(4),and N_(2)O are greenhou... Because of their effect on climate,carbon dioxide(CO_(2)),methane(CH_(4)),nitrous oxide(N_(2)O),and dimethylsulfide(DMS)are collectively designated as climate-relevant gases(CRGs).CO_(2),CH_(4),and N_(2)O are greenhouse gases contributing to global warming(positive climate feedback).Conversely,DMS is involved in the generation of cloud condensation nuclei,thus in the formation of clouds that cool the boundary layer by reflecting incoming solar radiation(negative climate feedback).Despite their scarcity,field observations and model results have demonstrated the essential role of polar oceans in the budget of CRGs.For example,the Southern Ocean represents a substantial CO_(2)sink but a source of N_(2)O and DMS,thereby exerting variable feedback on climate change.Unfortunately,because of the severe environmental conditions at polar latitudes,substantial knowledge gaps remain,for example on the mechanisms underlying CRGs formation or on the strength and distribution of their sources and sinks in the Southern and Arctic Oceans.Here,we review the most recent research results on the distribution,production-loss processes,and abundance variations of CRGs in the polar oceans.We list the remaining knowledge gaps and propose future directions of research on CRGs in the polar oceans,as a useful reference for future studies. 展开更多
关键词 POLAR ocean Arctic ocean Southern ocean climate-relavent gases greenhouse gases
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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation 被引量:1
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 ocean RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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Constraints on closure timing of Jilin–Heilongjiang Ocean by geochemical characteristics of blueschists and zircon U–Pb dating of Heilongjiang Complex
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作者 BAI Shurui ZHAO Liangliang +3 位作者 CHEN Zhuo ZHOU Jianbo LI Chengqiang LI Gongyu 《Global Geology》 2025年第2期125-138,共14页
There have always been academic debates regarding the timing and geodynamics of the superimposition and transformation between the Paleo-Pacific Ocean and the Paleo-Asian Ocean.To resolve the relevant issues over this... There have always been academic debates regarding the timing and geodynamics of the superimposition and transformation between the Paleo-Pacific Ocean and the Paleo-Asian Ocean.To resolve the relevant issues over this debate,the authors selected the Jilin–Heilongjiang high-pressure metamorphic belt(Ji–Hei HP Belt)between the Jiamusi–Khanka Block and the Songliao Block in NE China as the study area.This area preserves important records of the superimposition and transformation between these two tectonic domains.This study aims to address this issue through geochemical and zircon U–Pb dating analyses of the Yilan blueschist of Heilongjiang Complex exposed in the Ji–Hei HP Belt.In the geochemical analysis,it has been discovered that the protoliths of the blueschist in the Yilan area consist of subalkaline basalt,which displays geochemical characteristics of Ocean Island Basalt that indicated an oceanic island setting.The LA–ICP–MS zircon U–Pb analysis yields ages of 248±4 Ma and 259±2 Ma from the magma zircons of the blueschists,indicating that the basalt protolith was formed in Late Permian to Early Triassic(259–248 Ma).Based on the results of this study and the regional data,it is proposed that the Jilin–Heilongjiang Ocean opened during Late Permian to Early Triassic(259–248 Ma).This period marks a crucial stage from the closure of the Paleo-Asian Ocean to the initiation of Paleo-Pacific oceanic subduction. 展开更多
关键词 Paleo-Pacific ocean Paleo-Asian ocean ZIRCON Jilin–Heilongjiang ocean
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Characteristics,interannual variation,and influence mechanisms of a double-halocline in the western Arctic Ocean during 2002 to 2022
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作者 Yu Zhang Tao Li +4 位作者 Guoping Gao Hongxin Zhang Yubin Yao Xingyuan Zhu Yongjun Wang 《Acta Oceanologica Sinica》 2025年第3期57-70,共14页
A halocline in the Arctic Ocean significantly slows the upward heat flux from deep warm water,thereby inhibiting the melting of surface sea ice.The western Arctic Ocean exhibits a double-halocline(DH)structure due to ... A halocline in the Arctic Ocean significantly slows the upward heat flux from deep warm water,thereby inhibiting the melting of surface sea ice.The western Arctic Ocean exhibits a double-halocline(DH)structure due to the complexity of the water mass.Using in situ measurements,we analyzed the vertical structural characteristics of DH and its interannual variation.The results indicated that the DH primarily occurs at the Northwind Ridge and the southern Canada Basin,extending westward to the Chukchi Abyssal Plain and northward to the northern boundary of the Canada Basin.From 2002 to 2022,there were changes in water masses that determined the structure of the DH.The significant increase in Pacific Water has resulted in 42%and 65%increases in freshwater and the heat content of the DH,respectively,along with a 14%reduction in stratification.Pacific Winter Water characterized by salinity of 33 has exhibited a gradually decreasing trend,suggesting that the lower halocline may be difficult to ventilate.The combined effects of Ekman pumping,mesoscale eddies,and positive buoyancy forcing(heat and freshwater input)from Pacific Water have altered the thickness and stratification of the DH.This study has enhanced our understanding of the evolution of vertical heat flux in the upper western Arctic Ocean. 展开更多
关键词 western Arctic ocean double-halocline ocean stratification buoyancy forcing
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Sun-Related Energy, Induced Ring, Auroral Electrojet and Magnetopause Currents Variability during Solar Cycles 23 and 24
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作者 Issamaïl Ki M’Bi Kaboré +1 位作者 Somaïla Koala Jean Louis Zerbo 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期110-119,共10页
In this study, we examined variability of sun-related energies, auroral electrojet current, ring current, and magnetopause current during solar cycles 23 and 24. The study revealed a dependence of sun-related energies... In this study, we examined variability of sun-related energies, auroral electrojet current, ring current, and magnetopause current during solar cycles 23 and 24. The study revealed a dependence of sun-related energies to the Sun and Earth currents systems with solar activity from 1996 to 2019. A decrease in the correlation between sun-related energies and sunspot number was observed over solar cycles 23 and 24 (0.88 for the solar cycle 23 and 0.66 for the solar cycle 24), with a drop in the speed of magnetic disturbances in the solar wind. These results could be attributed to the decrease in Sun’s magnetic field toroidal component magnitude induced by a weak in sunspots number and solar flares during the solar cycle 24. A weak in the Earth currents systems (auroral electrojet current, ring current, and magnetopause current) is also observed. During the decrease in the Earth currents, several peaks are observed, indicating a nonlinear dependence in the Earth currents variation (ring current, auroral electrojet current, and magnetopause current) from solar cycle 23 to solar cycle 24. This could be attributed to the Corotating Interaction Regions (CIRs) observed during the declining phase of solar cycle 23 and the deep minimum preceding solar cycle 24. 展开更多
关键词 Solar Activity Sun-Related Energy Corotating Interaction Region currents Systems
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Record High Temperatures in the Ocean in 2024
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作者 Lijing CHENG John ABRAHAM +51 位作者 Kevin E.TRENBERTH James REAGAN Huai-Min ZHANG Andrea STORTO Karina VON SCHUCKMANN Yuying PAN Yujing ZHU Michael E.MANN Jiang ZHU Fan WANG Fujiang YU Ricardo LOCARNINI John FASULLO Boyin HUANG Garrett GRAHAM Xungang YIN Viktor GOURETSKI Fei ZHENG Yuanlong LI Bin ZHANG Liying WAN Xingrong CHEN Dakui WANG Licheng FENG Xiangzhou SONG Yulong LIU Franco RESEGHETTI Simona SIMONCELLI Gengxin CHEN Rongwang ZHANG Alexey MISHONOV Zhetao TAN Wangxu WEI Huifeng YUAN Guancheng LI Qiuping REN Lijuan CAO Yayang LU Juan DU Kewei LYU Albertus SULAIMAN Michael MAYER Huizan WANG Zhanhong MA Senliang BAO Henqian YAN Zenghong LIU Chunxue YANG Xu LIU Zeke HAUSFATHER Tanguy SZEKELY Flora GUES 《Advances in Atmospheric Sciences》 2025年第6期1092-1109,共18页
Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temper... Heating in the ocean has continued in 2024 in response to increased greenhouse gas concentrations in the atmosphere,despite the transition from an El Ni?o to neutral conditions. In 2024, both global sea surface temperature(SST) and upper2000 m ocean heat content(OHC) reached unprecedented highs in the historical record. The 0–2000 m OHC in 2024exceeded that of 2023 by 16 ± 8 ZJ(1 Zetta Joules = 1021 Joules, with a 95% confidence interval)(IAP/CAS data), which is confirmed by two other data products: 18 ± 7 ZJ(CIGAR-RT reanalysis data) and 40 ± 31 ZJ(Copernicus Marine data,updated to November 2024). The Indian Ocean, tropical Atlantic, Mediterranean Sea, North Atlantic, North Pacific, and Southern Ocean also experienced record-high OHC values in 2024. The global SST continued its record-high values from2023 into the first half of 2024, and declined slightly in the second half of 2024, resulting in an annual mean of 0.61°C ±0.02°C(IAP/CAS data) above the 1981–2010 baseline, slightly higher than the 2023 annual-mean value(by 0.07°C ±0.02°C for IAP/CAS, 0.05°C ± 0.02°C for NOAA/NCEI, and 0.06°C ± 0.11°C for Copernicus Marine). The record-high values of 2024 SST and OHC continue to indicate unabated trends of global heating. 展开更多
关键词 ocean heat content sea surface temperature ocean temperature global warming CLIMATE
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Ocean exploration journey
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作者 易静 《疯狂英语(新读写)》 2025年第8期69-70,80,共3页
Dr Emily Thompson decided it was time to set sail on her first major maritime research expedition.She had always been fascinated by the mysteries of the ocean and wanted to uncover the secrets hidden beneath the waves... Dr Emily Thompson decided it was time to set sail on her first major maritime research expedition.She had always been fascinated by the mysteries of the ocean and wanted to uncover the secrets hidden beneath the waves.Her team boarded the research vessel early in the morning,excited at the adventure that awaited them. 展开更多
关键词 secrets sea mysteries ocean research vessel maritime research uncover secrets hidden beneath ocean exploration
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