In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural a...In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural and anthropogenic effects on marine aerosols optical properties,as well as the applicability of multi-satellite products and IMPROVE equation.The averaged aerosol optical depth(AOD500 nm)was 0.31±0.16 andÅngström exponent440–675 nm was 0.29±0.30.In offshore China,significant anthropogenic emissions affected the marine environment.In remote WPO,dust aerosols transported from northern China,Siberia,Central Asia,and those settling from the upper troposphere originating from north Africa,Arabian peninsula,and western India,were dominant.The spatial trends of AOD were opposite in the mid-latitude and southern seas of WPO.The highest AOD,0.32±0.23,appeared along the coast of South Asia at mid-latitude,decreasing from offshore seas to remote oceans.In low-latitude and equatorial seas,AOD significantly increased from coast to remote oceans.Ångström exponent dropped significantly from the coast to remote oceans as anthropogenic influence diminished across the entire WPO.Correlation analysis showed that both MODIS-C6 and Himawari AOD prod-ucts showed similar applicability in coastal urban areas,while Himawari AOD is highly recommended for coastal background and marine environment due to its finer resolution.The extinction coefficient derived from PM_(2.5) chemical compositions using IMPROVE algorithm exhibited a significant correlation(R^(2)=0.58)with the con-currently measured AOD in the absence of long-distance transport,suggesting that the IMPROVE is a reasonable proxy of the columnar average of marine aerosol extinctions free from transport influences.展开更多
Based on reanalysis data from 1979 to 2021,this study explores the spatial distribution of the Southern Indian Ocean Dipole(SIOD)and its individual and synergistic effects with the El Niño-Southern Oscillation(EN...Based on reanalysis data from 1979 to 2021,this study explores the spatial distribution of the Southern Indian Ocean Dipole(SIOD)and its individual and synergistic effects with the El Niño-Southern Oscillation(ENSO)on summer precipitation in China.The inverse phase spatial distribution of sea surface temperature anomalies(SSTAs)in the southwest and northeast of the southern Indian Ocean is defined as the SIOD.Positive SIOD events(positive SSTAs in the southwest,negative SSTAs in the northeast)are associated with La Niña events(Central Pacific(CP)type),while negative SIOD events(negative SSTAs in the southwest,positive SSTAs in the northeast)are associated with El Niño events(Eastern Pacific(EP)type).Both SIOD and ENSO have certain impacts on summer precipitation in China.Precipitation in the Yangtze River basin decreases,while precipitation in southern China increases during pure positive SIOD(P_PSIOD)events.During pure negative SIOD(P_NSIOD)events,the changes in precipitation are exactly the opposite of those during P_PSIOD events,which may be due to differences in the cross-equatorial flow in the southern Indian Ocean,particularly in low-level Australian cross-equatorial flow.When positive SIOD and CP-type La Niña events occur simultaneously(PSIOD+La_Niña),precipitation increases in the Yangtze-Huaihe River basin,while it decreases in northern China.When negative SIOD and EP-type El Niño events occur simultaneously(NSIOD+El_Niño),precipitation in the Yangtze-Huaihe River basin is significantly lower than during P_NSIOD events.This is caused by differences in water vapor originating from the Pacific Ocean during different events.展开更多
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
This review compiles studies on paleoceanographic and paleoenvironmental changes in the high-latitude Southern Ocean during the late Quaternary based on Chinese Antarctic Expeditions.Four major findings are summarized...This review compiles studies on paleoceanographic and paleoenvironmental changes in the high-latitude Southern Ocean during the late Quaternary based on Chinese Antarctic Expeditions.Four major findings are summarized as follows.(1)Diatom compositions in sediment record sea surface condition changes in the Bransfield Strait and Cosmonaut Sea,indicating an increase in sea ice cover since the Mid-Holocene for both areas,possibly linked to cold water mass injection from the Weddell Sea ice shelf.(2)Export productivity records from Antarctic marginal seas show a glacial-interglacial variation pattern,with higher and lower productivity during the interglacial and glacial periods,respectively,controlled by both the intensity of Circumpolar Deep Water upwelling and sea ice cover.An overall increase of export productivity from Marine Isotope Stage(MIS)12 to MIS 6 is noticed.(3)Ventilation state of the abyssal Southern Ocean is closely related to global climate change and atmospheric CO_(2) concentrations,with elevated ventilation efficiency during deglacial periods responsible for elevated atmospheric CO_(2) concentrations.(4)Antarctic marine-based ice sheets/glaciers wax and wane in line with global and regional ice volume changes,predominantly subject to oceanic forcing,while land-based ice sheets might only reorganize in specific glacial intervals.Despite significant progress in understanding the role of the Southern Ocean and the Antarctic Ice Sheet within the global climate system,challenges remain in sample collection and research methods.Future studies should aim to collect samples from a broader range of latitudes,ensure higher quality and longer temporal span,resolve dating issues,reconstruct seawater temperature,and focus on reconstructions of Southern Ocean carbon cycling and changes of intermediate to deep water masses.展开更多
This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural la...This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development.展开更多
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
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
The Argentine shortfin squid Illex argentinus is an economically important short-lived species widely distributed in the southwest Atlantic Ocean.The abundance and distribution of I.argentinus are associated with clim...The Argentine shortfin squid Illex argentinus is an economically important short-lived species widely distributed in the southwest Atlantic Ocean.The abundance and distribution of I.argentinus are associated with climate change and environmental fluctuations.The potential distribution of I.argentinus was modeled with various environmental variables including sea surface temperature(SST),sea surface height(SSH),chlorophyll a,sea surface salinity(SSS),net primary productivity(NPP),mixed layer depth(MLD),eddy kinetic energy(EKE),and photosynthetically active radiation(PAR)using the maximum entropy(MaxEnt)approach during the peak fishing seasons(January–April).The habitat suitability index(HSI)was defined as the probability of species emergence from the MaxEnt model and the area of HSI≥0.6 was regarded as suitable.Results indicate that the predicted habitat correlated with the actual fishing position,with similar trends in the percentages of suitable habitats and catch per unit effort(CPUE)of I.argentinus from January to April.Moreover,SST,SSH,PAR,and MLD were identified critical environmental variables for the distribution of I.argentinus.In addition,the median of preferred ranges of the critical environmental variables were concentrated within the suitable habitats of I.argentinus.The Area under the Receiver Operating Characteristic Curve(AUC)was greater than 0.96 for all four months.Variations in latitudinal and longitudinal gravity centers(LATG and LONG)of fishing effort were consistent with latitudinal and longitudinal gravity centers(LATG_H and LONG_H)of the HSI.Our findings suggest that the MaxEnt model is an effective tool to predict the potential distribution of I.argentinus.Meanwhile,SST,SSH,PAR,and MLD should be given with more extensive attention in predicting the potential distribution of I.argentinus,as they are important environmental indicators that can help decision-makers search for the fishing ground of I.argentinus in the Southwest Atlantic.展开更多
El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).T...El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).This study explores the potential influences of tropical Indian Ocean(TIO)decadal variability on TA based on a comparative analysis of the relationship between the TIO sea surface temperature anomalies(SSTA)and ENSO during different periods.Generally,the TIO SSTA strengthened TA before the 1980s,corresponding to a highly positive relationship between the whole TIO SSTA and ENSO.However,the weakening effect was exhibited after the 1980s when the correlation diminished.After the late 1990s,ENSO was only positively correlated with western TIO,with the westerly exhibit of the SSTA center leading to smaller impacts on TA.Moreover,TIO SSTA tends to weaken TA by promoting the transition efficiency of La Niña,while bringing little effect on that of El Niño.Physically,compared to the mid-1970s,TIO SSTA triggered westerly wind anomalies during the autumn and winter of the La Niña development phase in the central equatorial Pacific in the late 1990s,which sped up the decay of La Niña.It then regenerated westerly anomalies in the following winter,facilitating the development of El Niño.This study quantifies the impact of the TIO SSTA on TA in seasonal signals and investigates the decadal variability of such influence,aiming to further understand phase transition asymmetry and offer valuable insights for the prediction of multi-year La Niña.展开更多
Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusio...Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusion and size of lipid droplets.Nannochloropsis oceanica is a model oleaginous microalga with the accumulation potential of fatty acids.We believe that the SEIPIN homolog if any in N.oceanica should function as it does in humans,plant among others.In this study,we identified a homologous gene of SEIPIN in N.oceanica,constructed a bacterial plasmid containing the elements controlling the transcription of its complete antisense RNA,and integrated the linearized plasmid into the N.oceanica genome.We obtained a transformant in which the abundance of SEIPIN transcript is significantly down-regulated.Flow cytometry analysis showed that the triacylglycerol(TAG)content of the transformant is significantly lower than that of the wild type(WT).Transcriptomic analysis showed that the down-regulation of SEIPIN transcript abundance could affect the protein functioning in endoplasmic reticulum(ER),implying that SEIPIN gene can function in N.oceanica in a similar way to that in A.thaliana.展开更多
Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries production.Climate-driven changes in the marine environment play a crucial role in their population dynamics.Us...Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries production.Climate-driven changes in the marine environment play a crucial role in their population dynamics.Using Chilean jack mackerel(Trachurus murphyi)as an example,this study conducted simulations to quantify the impacts of environmental variations on the stock assessment.A habitat-based surplus production model was developed by integrating suitable habitat area into the model parameters carrying capacity(K)and intrinsic growth rate(r),with a suitable habitat area serving as the proxy for the environmental conditions for Chilean jack mackerel in the Southeast Pacific Ocean.The dynamics of Chilean jack mackerel stock and fisheries data were simulated,and four assessment models with different configurations were built to fit simulated data,with or without considering environmental effects.The results indicated that Joint K-r model,which integrated both parameters with the suitable habitat area index,outperformed the others by coming closest to the‘true'population dynamics.Ignoring habitat variations in the estimation model tended to overestimate biomass and underestimate harvest rate and reference points.Without observation and process error,the results were estimated with bias,while FMSY is relatively sensitive.This research illustrates the importance to consider random errors and environmental influences on populations,and provides foundation guidelines for future stock assessment.展开更多
The multiscale variability in summer extreme persistent precipitation(SEPP)in China from 1961 to 2020 was investigated via three extreme precipitation indices:consecutive wet days,total precipitation amount,and daily ...The multiscale variability in summer extreme persistent precipitation(SEPP)in China from 1961 to 2020 was investigated via three extreme precipitation indices:consecutive wet days,total precipitation amount,and daily precipitation intensity.The relationships between precursory and concurrent global oceanic modes and SEPP were identified via a generalized linear model(GLM).The influence of oceanic modes on SEPP was finally investigated via numerical simulations.The results revealed that the climatological SEPP(≥14 days)mainly appears across the Tibetan Plateau,Yunnan–Guizhou Plateau,and South China coast.The first EOF mode for all three indices showed strong signals over the Yangtze River.Further analysis via the GLM suggested that the positive phases of the tropical North Atlantic(TNA)in autumn,ENSO in winter,the Indian Ocean Basin(IOB)in spring,and the western North Pacific(WNP)in summer emerged as the most effective precursory factors of SEPP,which could serve as preceding signals for future predictions,contributing 30.2%,36.4%,38.0%,and 55.6%,respectively,to the GLM.Sensitivity experiments revealed that SST forcing in all four seasons contributes to SEPP over China,whereas the winter and summer SST warming over the Pacific and Indian Ocean(IO)contributes the most.Diagnosis of the hydrological cycle suggested that water vapor advection predominantly originates from the western Pacific and IO in summer,driven by the strengthened subtropical high and Asian summer monsoon(ASM).The enhanced vertical water vapor transport is attributed to stronger upward motion across all four seasons.These findings are helpful for better understanding SEPP variabilities and their prediction under SST warming.展开更多
In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Pe...In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Peninsula in February 1985.Forty years later,in February 2024,China’s fifth research station,Qinling Station,commenced operations on Inexpress-ible Island near Terra Nova Bay.展开更多
The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface t...The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface type,cloud type,cloud phase,and aerosol type.To explore the impact of different underlying surfaces on the effect of aerosols on cloud development,this study focused on the Yangtze River Delta(YRD)and its offshore regions(YRD sea)for a comparative analysis based on multi-source satellite data,while also considering the variations in cloud type and cloud phase.The results show lower cloud-top height and depth of single-layer clouds over the ocean than land,and higher liquid cloud in spring over the ocean.Aerosols are found to enhance the cumulus cloud depth through microphysical effects,which is particularly evident over the ocean.Aerosols are also found to decrease the cloud droplet effective radius in the ocean region and during the mature stage of cloud development in the land region,while opposite results are found during the early stage of cloud development in the land region.The quantitative results indicate that the indirect effect is positive(0.05)in the land region at relatively high cloud water path,which is smaller than that in the ocean region(0.11).The findings deepen our understanding of the influence aerosols on cloud development and the mechanisms involved,which could then be applied to improve the ability to simulate cloud-associated weather processes.展开更多
In the Arctic Ocean,turbulent mixing drives vertical heat flux,thereby affecting the sea ice variability.Internal wave is regarded as one of the important energy sources of mixing in this region.The high latitude and ...In the Arctic Ocean,turbulent mixing drives vertical heat flux,thereby affecting the sea ice variability.Internal wave is regarded as one of the important energy sources of mixing in this region.The high latitude and sea ice cover make internal wave in the Arctic Ocean apparently differs from that in mid-and low-latitude oceans.However,the internal wave and its underlying mechanism are less understood due to the lack of observations.This paper briefly reviews the recent studies and unresolved questions on the internal wave in the Arctic Ocean,including wind-driven near-inertial wave,internal tide,and high-frequency internal wave.The aim is to provide new insights for in-depth research in the future,with a focus on the mechanisms responsible for the evolution of internal wave under the rapidly changing Arctic climate.展开更多
Motivated by the wide applications of empirical global ocean tide models in Earth science,particularly in shallow waters and coastal regions,we proposed an updated global ocean tide model representing all major diurna...Motivated by the wide applications of empirical global ocean tide models in Earth science,particularly in shallow waters and coastal regions,we proposed an updated global ocean tide model representing all major diurnal and semidiurnal tidal constituents.We integrated the development technique of the Technical University of Denmark(DTU10)model and calculated the residual tides using the intermediary FES2012 model.We utilized all available Topex/Poseidon,Jason-1,Ocean Surface Topography Mission(OSTM)/Jason-2 primary and tandem missions to develop the new model.To reduce the discrepancies between the model and in situ measurements estimated S2 tide constituent,the ERA-Interim model was selected for dry tropospheric correction of altimetry data.The newly developed model with an improved spatial resolution from 1/8°×1/8°to 1/16°×1/16°was assessed and compared against contemporary global ocean tide models using in situ measurements in coastal regions,continental shelf waters,marginal seas,and deep waters.The results demonstrate improvements in shallow waters and coastal regions,particularly in representative coastal re-gions such as the Northwest European Shelf and East Asian Marginal Seas.Moreover,the model performs well in simulating S_(2) and K_(2) tides with root mean square differences of 0.355 and 0.234 cm,respectively,against in situ measurements in deep waters world-wide.Compared with that of DTU10,the root sum square of the new model for the eight main tidal constituents decrease by 8.4%to 0.997 cm.展开更多
1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and g...1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and gas,renewable energy,minerals,and marine biodiversity,forming a crucial component of global life-support systems and representing a valuable asset for human survival and development[1].Moreover,as shown in Fig.1[2],the ocean sectors offer a critical avenue for contributing to many of the 17 United Nations Sustainable Development Goals for global development[3].展开更多
Subduction initiation is a critical part of the plate tectonic system,but its geodynamic process is still poorly understood due to the lack of well-preserved geological records.Based on new zircon U–Pb–Hf isotopic a...Subduction initiation is a critical part of the plate tectonic system,but its geodynamic process is still poorly understood due to the lack of well-preserved geological records.Based on new zircon U–Pb–Hf isotopic and whole-rock geochemical data,we report the first discovery of a latest Cambrian–Early Ordovician forearc-arc rock sequence in the Eastern Alps.This sequence includes granitic gneisses,amphibolites,and amphibole plagiogneisses from the ophiolitic Speik Complex and Gleinalpe Complex.These rocks exhibit geochemical affinities with typical oceanic plagiogranites,forearc basalts(FABs),and island arc basalts,respectively.The latest Cambrian plagiogranitic protoliths(491±2 Ma)are shearing-type plagiogranites that were formed in the tectonic setting of forearc spreading.The latest Cambrian FABs(496–489 Ma)have similar geochemical compositions and positiveεHf(t)values(+2.5 to+14.9)to the depleted mid-ocean ridge basalts.However,they show depletion in high field strength elements(HFSEs;e.g.,Nb,Ta,and Zr)and have relatively low Ti/V ratios.These features suggest that they were derived from a depleted mantle source modified by subducting slab-released components in a forearc environment.The Early Ordovician basaltic protoliths(476–472 Ma)of amphibole plagiogneisses show enrichment in large ion lithophile elements and depletion in HFSEs(e.g.Nb,Ta,Zr,and Hf),implying a mature island arc environment.These metaigneous rocks,along with the coeval boninite-like high-Mg amphibolites near the study area,form a typical rock sequence resembling that of the Izu–Bonin–Mariana(IBM)arc system.The Speik and Gleinalpe complexes document a complete magmatic evolution from subduction initiation to mature arc development within the West Proto-Tethys Ocean.Integrating our new data with published work,we reconstruct the late Ediacaran–early Paleozoic tectonic evolution of the northern Gondwana.During the late Ediacaran–early Cambrian,the rollback of the West Proto-Tethys oceanic plate triggered the separation of the Wechsel-Silvretta-Gleinalpe continental arc from the northern Gondwana.This process led to the formation of the Speik back-arc oceanic basin,a southwestern branch of the West Proto-Tethys Ocean.In the latest Cambrian–Early Ordovician,subduction initiation occurred in the Speik Ocean,which subsequently developed into an intra-oceanic arc system.During the Early Devonian,the Speik Ocean closed and the Wechsel-Silvretta-Gleinalpe continental arc reattached to the Gondwana,as evidenced by the metamorphic event at ca.400 Ma.展开更多
The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(E...The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.展开更多
Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature...Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature drop of Shanwei meteorological station,two extreme cold surges and five weak cold invasions in the South China Sea are simulated using an ocean-atmosphere coupled model to investigate their different impacts on the upper-ocean temperature.The diffusion term contributes to the difference in temperature tendency of the upper 20 m,while the advection term contributes to the positive difference from 20 to 80 m of the offshore region and negative difference from 80 to 160 m.In addition,the significant differences are attributed primarily to the influence of the upper-ocean temperature gradient,which subsequently impacts the advection term and results in notable differences in temperature tendency at depths from 80 to 160 m.展开更多
基金supported by the CAS Strategic Priority Research Program(No.XDB0760102),the Ministry of Science and Technology of China(No.2022YFF0802501)the Major Science and Technology Infrastructure Maintenance and Transformation Project of the Chinese Academy of Sciences,Shanghai Science and Technology Innovation Action Plan-Phospherus Project(No.23YF1426200)the National Key Research and Development Program of China(No.2024YFE0212200).
文摘In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural and anthropogenic effects on marine aerosols optical properties,as well as the applicability of multi-satellite products and IMPROVE equation.The averaged aerosol optical depth(AOD500 nm)was 0.31±0.16 andÅngström exponent440–675 nm was 0.29±0.30.In offshore China,significant anthropogenic emissions affected the marine environment.In remote WPO,dust aerosols transported from northern China,Siberia,Central Asia,and those settling from the upper troposphere originating from north Africa,Arabian peninsula,and western India,were dominant.The spatial trends of AOD were opposite in the mid-latitude and southern seas of WPO.The highest AOD,0.32±0.23,appeared along the coast of South Asia at mid-latitude,decreasing from offshore seas to remote oceans.In low-latitude and equatorial seas,AOD significantly increased from coast to remote oceans.Ångström exponent dropped significantly from the coast to remote oceans as anthropogenic influence diminished across the entire WPO.Correlation analysis showed that both MODIS-C6 and Himawari AOD prod-ucts showed similar applicability in coastal urban areas,while Himawari AOD is highly recommended for coastal background and marine environment due to its finer resolution.The extinction coefficient derived from PM_(2.5) chemical compositions using IMPROVE algorithm exhibited a significant correlation(R^(2)=0.58)with the con-currently measured AOD in the absence of long-distance transport,suggesting that the IMPROVE is a reasonable proxy of the columnar average of marine aerosol extinctions free from transport influences.
基金supported by the National Natural Science Foundation of China[grant numbers 41975087,U2242212,and 41975085]supported by the National Natural Science Foundation of China[grant number U2242212]。
文摘Based on reanalysis data from 1979 to 2021,this study explores the spatial distribution of the Southern Indian Ocean Dipole(SIOD)and its individual and synergistic effects with the El Niño-Southern Oscillation(ENSO)on summer precipitation in China.The inverse phase spatial distribution of sea surface temperature anomalies(SSTAs)in the southwest and northeast of the southern Indian Ocean is defined as the SIOD.Positive SIOD events(positive SSTAs in the southwest,negative SSTAs in the northeast)are associated with La Niña events(Central Pacific(CP)type),while negative SIOD events(negative SSTAs in the southwest,positive SSTAs in the northeast)are associated with El Niño events(Eastern Pacific(EP)type).Both SIOD and ENSO have certain impacts on summer precipitation in China.Precipitation in the Yangtze River basin decreases,while precipitation in southern China increases during pure positive SIOD(P_PSIOD)events.During pure negative SIOD(P_NSIOD)events,the changes in precipitation are exactly the opposite of those during P_PSIOD events,which may be due to differences in the cross-equatorial flow in the southern Indian Ocean,particularly in low-level Australian cross-equatorial flow.When positive SIOD and CP-type La Niña events occur simultaneously(PSIOD+La_Niña),precipitation increases in the Yangtze-Huaihe River basin,while it decreases in northern China.When negative SIOD and EP-type El Niño events occur simultaneously(NSIOD+El_Niño),precipitation in the Yangtze-Huaihe River basin is significantly lower than during P_NSIOD events.This is caused by differences in water vapor originating from the Pacific Ocean during different events.
基金The National Key Research and Development Program of China under contract No.2023YFC2809101the National Natural Science Foundation of China under contract No.42276239.
文摘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.
基金The National Natural Science Foundation of China under contract Nos 42030401 and 42276077the Open Foundation of State Key Laboratory of Marine Geology,Tongji University under contract No.MGK202207+1 种基金the Open Foundation Project of the Key Laboratory of Polar Geology and Marine Mineral Resources of Ministry of Education,China University of Geosciences (Beijing),under contract Nos PGMR-2024-102 and PGMR-2023-304the Start-up Foundation of Guangdong Ocean University under contract No.060302032110
文摘This review compiles studies on paleoceanographic and paleoenvironmental changes in the high-latitude Southern Ocean during the late Quaternary based on Chinese Antarctic Expeditions.Four major findings are summarized as follows.(1)Diatom compositions in sediment record sea surface condition changes in the Bransfield Strait and Cosmonaut Sea,indicating an increase in sea ice cover since the Mid-Holocene for both areas,possibly linked to cold water mass injection from the Weddell Sea ice shelf.(2)Export productivity records from Antarctic marginal seas show a glacial-interglacial variation pattern,with higher and lower productivity during the interglacial and glacial periods,respectively,controlled by both the intensity of Circumpolar Deep Water upwelling and sea ice cover.An overall increase of export productivity from Marine Isotope Stage(MIS)12 to MIS 6 is noticed.(3)Ventilation state of the abyssal Southern Ocean is closely related to global climate change and atmospheric CO_(2) concentrations,with elevated ventilation efficiency during deglacial periods responsible for elevated atmospheric CO_(2) concentrations.(4)Antarctic marine-based ice sheets/glaciers wax and wane in line with global and regional ice volume changes,predominantly subject to oceanic forcing,while land-based ice sheets might only reorganize in specific glacial intervals.Despite significant progress in understanding the role of the Southern Ocean and the Antarctic Ice Sheet within the global climate system,challenges remain in sample collection and research methods.Future studies should aim to collect samples from a broader range of latitudes,ensure higher quality and longer temporal span,resolve dating issues,reconstruct seawater temperature,and focus on reconstructions of Southern Ocean carbon cycling and changes of intermediate to deep water masses.
基金Supported by Remote Sensing Support for Offshore Ocean Environment and Polar Sea Ice Early Warning Services(102121201550000009004)。
文摘This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development.
基金supported by the National Key R&D Program of China (Grant No.2023YFF0806500)the International Partnership Program of the Chinese Academy of Sciences (Grant No.060GJHZ2024064MI)+10 种基金the Chinese Academy of Sciences and the National Research Council of Italy Scientific Cooperative Programmethe new Cornerstone Science Foundation through the XPLORER PRIZEthe National Key Scientific and Technological Infrastructure project “Earth System Science Numerical Simulator Facility” (Earth Lab), and Ocean Negative Carbon Emissions (ONCE)sponsored by the US National Science Foundationsupported by the Young Talent Support Project of Guangzhou Association for Science and Technologythe Open Research Cruise NORC2022-10+NORC2022-303 supported by NSFC shiptime Sharing Projects 42149910supported by NASA Awards 80NSSC17K0565, 80NSSC21K1191, and 80NSSC22K0046by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S.Department of Energy’s Office of Biological & Environmental Research (BER) via National Science Foundation IA 1947282supported by NOAA (Grant No.NA19NES4320002 to CISESS-MD at the University of Maryland)supported by the Austrian Science Fund (P33177)ESA (contract ref.4000145298/24/I-LR)。
文摘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.
基金supported by the National Natural Science Foundation of China(Grant Nos.42230405,42006029)Science and Technology Plan of Liaoning Province(2024JH2/102400061)+1 种基金Dalian Science and Technology Innovation Fund(2024JJ11PT007)Dalian Science and Technology Pro-gram for Innovation Talents of Dalian(2022RJ06).
文摘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.
基金Supported by the Natural Science Foundation of Shanghai(No.23ZR1427100)the National Key R&D Program of China(No.2023YFD2401303)the Shanghai Talent Development Funding for the Project(No.2021078)。
文摘The Argentine shortfin squid Illex argentinus is an economically important short-lived species widely distributed in the southwest Atlantic Ocean.The abundance and distribution of I.argentinus are associated with climate change and environmental fluctuations.The potential distribution of I.argentinus was modeled with various environmental variables including sea surface temperature(SST),sea surface height(SSH),chlorophyll a,sea surface salinity(SSS),net primary productivity(NPP),mixed layer depth(MLD),eddy kinetic energy(EKE),and photosynthetically active radiation(PAR)using the maximum entropy(MaxEnt)approach during the peak fishing seasons(January–April).The habitat suitability index(HSI)was defined as the probability of species emergence from the MaxEnt model and the area of HSI≥0.6 was regarded as suitable.Results indicate that the predicted habitat correlated with the actual fishing position,with similar trends in the percentages of suitable habitats and catch per unit effort(CPUE)of I.argentinus from January to April.Moreover,SST,SSH,PAR,and MLD were identified critical environmental variables for the distribution of I.argentinus.In addition,the median of preferred ranges of the critical environmental variables were concentrated within the suitable habitats of I.argentinus.The Area under the Receiver Operating Characteristic Curve(AUC)was greater than 0.96 for all four months.Variations in latitudinal and longitudinal gravity centers(LATG and LONG)of fishing effort were consistent with latitudinal and longitudinal gravity centers(LATG_H and LONG_H)of the HSI.Our findings suggest that the MaxEnt model is an effective tool to predict the potential distribution of I.argentinus.Meanwhile,SST,SSH,PAR,and MLD should be given with more extensive attention in predicting the potential distribution of I.argentinus,as they are important environmental indicators that can help decision-makers search for the fishing ground of I.argentinus in the Southwest Atlantic.
基金National Natural Science Foundation of China(42288101,42192564)Project of Ministry of Science and Technology of the People’s Republic of China(2020YFA0608802)Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)。
文摘El Niño is frequently followed by La Niña,while La Niña tends to sustain into the next year or even longer,exhibiting a notable phase transition asymmetry(TA)of El Niño-Southern Oscillation(ENSO).This study explores the potential influences of tropical Indian Ocean(TIO)decadal variability on TA based on a comparative analysis of the relationship between the TIO sea surface temperature anomalies(SSTA)and ENSO during different periods.Generally,the TIO SSTA strengthened TA before the 1980s,corresponding to a highly positive relationship between the whole TIO SSTA and ENSO.However,the weakening effect was exhibited after the 1980s when the correlation diminished.After the late 1990s,ENSO was only positively correlated with western TIO,with the westerly exhibit of the SSTA center leading to smaller impacts on TA.Moreover,TIO SSTA tends to weaken TA by promoting the transition efficiency of La Niña,while bringing little effect on that of El Niño.Physically,compared to the mid-1970s,TIO SSTA triggered westerly wind anomalies during the autumn and winter of the La Niña development phase in the central equatorial Pacific in the late 1990s,which sped up the decay of La Niña.It then regenerated westerly anomalies in the following winter,facilitating the development of El Niño.This study quantifies the impact of the TIO SSTA on TA in seasonal signals and investigates the decadal variability of such influence,aiming to further understand phase transition asymmetry and offer valuable insights for the prediction of multi-year La Niña.
基金Supported by the National Key R&D Program of China(No.2022YFF1102300)the Key R&D Program of Shandong Province,China(No.2022LZGC004)+2 种基金the National Natural Science Foundation of China(No.32102757)the Science&Technology Innovation Project of Laoshan Laboratory(No.LSKJ202203205)the Fundamental Research Funds for the Central Universities(No.202262001)。
文摘Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in humans.Previous studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusion and size of lipid droplets.Nannochloropsis oceanica is a model oleaginous microalga with the accumulation potential of fatty acids.We believe that the SEIPIN homolog if any in N.oceanica should function as it does in humans,plant among others.In this study,we identified a homologous gene of SEIPIN in N.oceanica,constructed a bacterial plasmid containing the elements controlling the transcription of its complete antisense RNA,and integrated the linearized plasmid into the N.oceanica genome.We obtained a transformant in which the abundance of SEIPIN transcript is significantly down-regulated.Flow cytometry analysis showed that the triacylglycerol(TAG)content of the transformant is significantly lower than that of the wild type(WT).Transcriptomic analysis showed that the down-regulation of SEIPIN transcript abundance could affect the protein functioning in endoplasmic reticulum(ER),implying that SEIPIN gene can function in N.oceanica in a similar way to that in A.thaliana.
基金supported by the National Key Research and Development Program of China(No.2019YFD0901404)。
文摘Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries production.Climate-driven changes in the marine environment play a crucial role in their population dynamics.Using Chilean jack mackerel(Trachurus murphyi)as an example,this study conducted simulations to quantify the impacts of environmental variations on the stock assessment.A habitat-based surplus production model was developed by integrating suitable habitat area into the model parameters carrying capacity(K)and intrinsic growth rate(r),with a suitable habitat area serving as the proxy for the environmental conditions for Chilean jack mackerel in the Southeast Pacific Ocean.The dynamics of Chilean jack mackerel stock and fisheries data were simulated,and four assessment models with different configurations were built to fit simulated data,with or without considering environmental effects.The results indicated that Joint K-r model,which integrated both parameters with the suitable habitat area index,outperformed the others by coming closest to the‘true'population dynamics.Ignoring habitat variations in the estimation model tended to overestimate biomass and underestimate harvest rate and reference points.Without observation and process error,the results were estimated with bias,while FMSY is relatively sensitive.This research illustrates the importance to consider random errors and environmental influences on populations,and provides foundation guidelines for future stock assessment.
基金jointly funded by the National Natural Science Foundation of China(Grant Nos.42122035,42288101,42130605,72293604,42475179,and 42475020)the support of the Guangdong Provincial Observation and Research Station for Tropical Ocean Environment in Western Coastal Waters(GSTOEW)+2 种基金Key Laboratory of Space Ocean Remote Sensing and ApplicationCMAGDOU Joint Laboratory for Marine MeteorologyKey Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Ocean(LCRE)。
文摘The multiscale variability in summer extreme persistent precipitation(SEPP)in China from 1961 to 2020 was investigated via three extreme precipitation indices:consecutive wet days,total precipitation amount,and daily precipitation intensity.The relationships between precursory and concurrent global oceanic modes and SEPP were identified via a generalized linear model(GLM).The influence of oceanic modes on SEPP was finally investigated via numerical simulations.The results revealed that the climatological SEPP(≥14 days)mainly appears across the Tibetan Plateau,Yunnan–Guizhou Plateau,and South China coast.The first EOF mode for all three indices showed strong signals over the Yangtze River.Further analysis via the GLM suggested that the positive phases of the tropical North Atlantic(TNA)in autumn,ENSO in winter,the Indian Ocean Basin(IOB)in spring,and the western North Pacific(WNP)in summer emerged as the most effective precursory factors of SEPP,which could serve as preceding signals for future predictions,contributing 30.2%,36.4%,38.0%,and 55.6%,respectively,to the GLM.Sensitivity experiments revealed that SST forcing in all four seasons contributes to SEPP over China,whereas the winter and summer SST warming over the Pacific and Indian Ocean(IO)contributes the most.Diagnosis of the hydrological cycle suggested that water vapor advection predominantly originates from the western Pacific and IO in summer,driven by the strengthened subtropical high and Asian summer monsoon(ASM).The enhanced vertical water vapor transport is attributed to stronger upward motion across all four seasons.These findings are helpful for better understanding SEPP variabilities and their prediction under SST warming.
文摘In November 1984,China launched its first expedition to the Southern Ocean and the Antarctic continent,culminating in the establishment of its first year-round research station—Great Wall Station—on the Antarctic Peninsula in February 1985.Forty years later,in February 2024,China’s fifth research station,Qinling Station,commenced operations on Inexpress-ible Island near Terra Nova Bay.
基金supported by the National Natural Science Foundation of China(Grant No.42230601).
文摘The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface type,cloud type,cloud phase,and aerosol type.To explore the impact of different underlying surfaces on the effect of aerosols on cloud development,this study focused on the Yangtze River Delta(YRD)and its offshore regions(YRD sea)for a comparative analysis based on multi-source satellite data,while also considering the variations in cloud type and cloud phase.The results show lower cloud-top height and depth of single-layer clouds over the ocean than land,and higher liquid cloud in spring over the ocean.Aerosols are found to enhance the cumulus cloud depth through microphysical effects,which is particularly evident over the ocean.Aerosols are also found to decrease the cloud droplet effective radius in the ocean region and during the mature stage of cloud development in the land region,while opposite results are found during the early stage of cloud development in the land region.The quantitative results indicate that the indirect effect is positive(0.05)in the land region at relatively high cloud water path,which is smaller than that in the ocean region(0.11).The findings deepen our understanding of the influence aerosols on cloud development and the mechanisms involved,which could then be applied to improve the ability to simulate cloud-associated weather processes.
基金supported by the National Natural Science Foundation of China(Grant no.42176244)CAS Key Deployment Project of Centre for Ocean Mega-Research of Science(Grant no.COMS2020Q07)。
文摘In the Arctic Ocean,turbulent mixing drives vertical heat flux,thereby affecting the sea ice variability.Internal wave is regarded as one of the important energy sources of mixing in this region.The high latitude and sea ice cover make internal wave in the Arctic Ocean apparently differs from that in mid-and low-latitude oceans.However,the internal wave and its underlying mechanism are less understood due to the lack of observations.This paper briefly reviews the recent studies and unresolved questions on the internal wave in the Arctic Ocean,including wind-driven near-inertial wave,internal tide,and high-frequency internal wave.The aim is to provide new insights for in-depth research in the future,with a focus on the mechanisms responsible for the evolution of internal wave under the rapidly changing Arctic climate.
基金supported by the open funding of the Technology Innovation Center for South China Sea Re-mote Sensing,Surveying and Mapping Collaborative Ap-plication,Ministry of Natural Resources,P.R.China(No.RSSMCA-2024-B001)the National Natural Science Foundation of China(Nos.T2261149752 and 42476172).
文摘Motivated by the wide applications of empirical global ocean tide models in Earth science,particularly in shallow waters and coastal regions,we proposed an updated global ocean tide model representing all major diurnal and semidiurnal tidal constituents.We integrated the development technique of the Technical University of Denmark(DTU10)model and calculated the residual tides using the intermediary FES2012 model.We utilized all available Topex/Poseidon,Jason-1,Ocean Surface Topography Mission(OSTM)/Jason-2 primary and tandem missions to develop the new model.To reduce the discrepancies between the model and in situ measurements estimated S2 tide constituent,the ERA-Interim model was selected for dry tropospheric correction of altimetry data.The newly developed model with an improved spatial resolution from 1/8°×1/8°to 1/16°×1/16°was assessed and compared against contemporary global ocean tide models using in situ measurements in coastal regions,continental shelf waters,marginal seas,and deep waters.The results demonstrate improvements in shallow waters and coastal regions,particularly in representative coastal re-gions such as the Northwest European Shelf and East Asian Marginal Seas.Moreover,the model performs well in simulating S_(2) and K_(2) tides with root mean square differences of 0.355 and 0.234 cm,respectively,against in situ measurements in deep waters world-wide.Compared with that of DTU10,the root sum square of the new model for the eight main tidal constituents decrease by 8.4%to 0.997 cm.
基金supported by the National Natural Science Foun-dation of China(52088102)the KeyR&DProgram of Shandong Province,China(2021ZLGX04).
文摘1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and gas,renewable energy,minerals,and marine biodiversity,forming a crucial component of global life-support systems and representing a valuable asset for human survival and development[1].Moreover,as shown in Fig.1[2],the ocean sectors offer a critical avenue for contributing to many of the 17 United Nations Sustainable Development Goals for global development[3].
基金supported by the National Natural Science Foundation of China(Grant Nos.42272244 and 91755212)Taishan Scholars(Grant No.ts20190918).
文摘Subduction initiation is a critical part of the plate tectonic system,but its geodynamic process is still poorly understood due to the lack of well-preserved geological records.Based on new zircon U–Pb–Hf isotopic and whole-rock geochemical data,we report the first discovery of a latest Cambrian–Early Ordovician forearc-arc rock sequence in the Eastern Alps.This sequence includes granitic gneisses,amphibolites,and amphibole plagiogneisses from the ophiolitic Speik Complex and Gleinalpe Complex.These rocks exhibit geochemical affinities with typical oceanic plagiogranites,forearc basalts(FABs),and island arc basalts,respectively.The latest Cambrian plagiogranitic protoliths(491±2 Ma)are shearing-type plagiogranites that were formed in the tectonic setting of forearc spreading.The latest Cambrian FABs(496–489 Ma)have similar geochemical compositions and positiveεHf(t)values(+2.5 to+14.9)to the depleted mid-ocean ridge basalts.However,they show depletion in high field strength elements(HFSEs;e.g.,Nb,Ta,and Zr)and have relatively low Ti/V ratios.These features suggest that they were derived from a depleted mantle source modified by subducting slab-released components in a forearc environment.The Early Ordovician basaltic protoliths(476–472 Ma)of amphibole plagiogneisses show enrichment in large ion lithophile elements and depletion in HFSEs(e.g.Nb,Ta,Zr,and Hf),implying a mature island arc environment.These metaigneous rocks,along with the coeval boninite-like high-Mg amphibolites near the study area,form a typical rock sequence resembling that of the Izu–Bonin–Mariana(IBM)arc system.The Speik and Gleinalpe complexes document a complete magmatic evolution from subduction initiation to mature arc development within the West Proto-Tethys Ocean.Integrating our new data with published work,we reconstruct the late Ediacaran–early Paleozoic tectonic evolution of the northern Gondwana.During the late Ediacaran–early Cambrian,the rollback of the West Proto-Tethys oceanic plate triggered the separation of the Wechsel-Silvretta-Gleinalpe continental arc from the northern Gondwana.This process led to the formation of the Speik back-arc oceanic basin,a southwestern branch of the West Proto-Tethys Ocean.In the latest Cambrian–Early Ordovician,subduction initiation occurred in the Speik Ocean,which subsequently developed into an intra-oceanic arc system.During the Early Devonian,the Speik Ocean closed and the Wechsel-Silvretta-Gleinalpe continental arc reattached to the Gondwana,as evidenced by the metamorphic event at ca.400 Ma.
基金The Fund of Laoshan Laboratory under contract No.LSKJ202202700the Basic Scientific Fund for National Public Research Institutes of China under contract No.2024Q02+1 种基金the National Natural Science Foundation of China under contract Nos 42076023 and 42430402the Global Change and Air-Sea InteractionⅡProject under contract No.GASI-01-ATP-STwin.
文摘The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year.
基金jointly supported by the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)[grant number SML2023SP240]the National Natural Science Foundation of China[grant number 92158204]。
文摘Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature drop of Shanwei meteorological station,two extreme cold surges and five weak cold invasions in the South China Sea are simulated using an ocean-atmosphere coupled model to investigate their different impacts on the upper-ocean temperature.The diffusion term contributes to the difference in temperature tendency of the upper 20 m,while the advection term contributes to the positive difference from 20 to 80 m of the offshore region and negative difference from 80 to 160 m.In addition,the significant differences are attributed primarily to the influence of the upper-ocean temperature gradient,which subsequently impacts the advection term and results in notable differences in temperature tendency at depths from 80 to 160 m.
