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991.
As a member of the Chinese modeling groups,the coupled ocean-ice component of the Chinese Academy of Sciences’Earth System Model,version 2.0(CAS-ESM2.0),is taking part in the Ocean Model Intercomparison Project Phase 1(OMIP1)experiment of phase 6 of the Coupled Model Intercomparison Project(CMIP6).The simulation was conducted,and monthly outputs have been published on the ESGF(Earth System Grid Federation)data server.In this paper,the experimental dataset is introduced,and the preliminary performances of the ocean model in simulating the global ocean temperature,salinity,sea surface temperature,sea surface salinity,sea surface height,sea ice,and Atlantic Meridional Overturning Circulation(AMOC)are evaluated.The results show that the model is at quasi-equilibrium during the integration of 372 years,and performances of the model are reasonable compared with observations.This dataset is ready to be downloaded and used by the community in related research,e.g.,multi-ocean-sea-ice model performance evaluation and interannual variation in oceans driven by prescribed atmospheric forcing.  相似文献   
992.
珠江口是粤港澳大湾区的核心区域,台风、风暴潮和巨浪等海洋灾害频发,对沿岸人民的生命财产安全构成严重威胁。准确的高分辨率波浪模拟/预报对区域经济建设和防灾减灾具有重要意义。波浪预报/模拟的质量很大程度上取决于风能输入的误差。本研究基于WAVEWATCH Ⅲ(WW3)的南海-珠江口双重嵌套精细化海浪模式,探讨不同的风场产品与风能输入参数方案组合对珠江口波浪动力过程模拟的影响,确定最优的风场和参数方案组合。ERA5风场更适合珠江口海域的风浪模拟,其模式结果略优于采用CFSR风场的模式结果。ERA5风场+T500方案的组合对珠江口波高变化过程的模拟效果最好,ERA5风场+T471方案的组合次之,ERA5风场+ST6方案再次之。CFSR风场与T471f参数方案最为适配,其结果稍差于ERA5风场+ST6参数方案。T500方案调整高风速下的风能输入和涌浪对风能输入的反馈作用,并考虑水深引起的波浪破碎效应,更适合水深限制的珠江口浅水区域。另外,WW3模式开关ST4的参数方案的表现优于开关ST6的参数方案。   相似文献   
993.
State-of-the-art coupled general circulation models(CGCMs)are used to predict ocean heat uptake(OHU)and sealevel change under global warming.However,the projections of different models vary,resulting in high uncertainty.Much of the inter-model spread is driven by responses to surface heat perturbations.This study mainly focuses on the response of the ocean to a surface heat flux perturbation F,as prescribed by the Flux-Anomaly-Forced Model Intercomparison Project(FAFMIP).The results of ocean model were compared with those of a CGCM with the same ocean component.On the global scale,the changes in global mean temperature,ocean heat content(OHC),and steric sea level(SSL)simulated in the OGCM are generally consistent with CGCM simulations.Differences in changes in ocean temperature,OHC,and SSL between the two models primarily occur in the Arctic and Atlantic Oceans(AA)and the Southern Ocean(SO)basins.In addition to the differences in surface heat flux anomalies between the two models,differences in heat exchange between basins also play an important role in the inconsistencies in ocean climate changes in the AA and SO basins.These discrepancies are largely due to both the larger initial value and the greater weakening change of the Atlantic meridional overturning circulation(AMOC)in CGCM.The greater weakening of the AMOC in the CGCM is associated with the atmosphere–ocean feedback and the lack of a restoring salinity boundary condition.Furthermore,differences in surface salinity boundary conditions between the two models contribute to discrepancies in SSL changes.  相似文献   
994.
国际大洋科学钻探可以追溯到20世纪60年代的“莫霍钻”计划。在50余年的历史中,经历了深海钻探计划、大洋钻探计划、综合大洋钻探计划和国际大洋发现计划四个阶段,执行了300多个航次的洋底钻探任务。所获得的海量、珍贵的洋底数据,如今保存在多个数据库中。这些数据包括了测井信息、岩芯基概况信息、物理属性信息、化学属性信息、岩石特征、古生物化石内容等观测和实验分析结果,数据量巨大。这些数据还通常附于相关的大洋钻探出版物中发表,部分被相关专业数据库收录。总体来看,大洋钻探目前的数字化工作存在多个数据库间数据类型不匹配和数据检索方式单调等问题,不利于后续对于数据的再挖掘和利用。未来需要重视综合性大数据平台的建设,将不同来源、不同类型的多源异构数据有效融合,互联互通,并充分利用已有的大数据技术手段支撑相关的科学研究。  相似文献   
995.
基于第五次国际间耦合模式比较计划(The phase 5 of the Coupled Model Intercomparison Project,CMIP5)中在4.5 W/m^2的典型浓度路径(Representative Concentration Pathway,RCP4.5)试验结果,本文通过能量框架分析方法研究了全球变暖不同阶段热带辐合带(Intertropical Convergence Zone,ITCZ)的南北移动及其主要机制,发现在温室气体持续增加的海洋快响应和温室气体达到稳定后的海洋慢响应两个阶段,ITCZ的移动都和跨赤道的大气能量输送(Atmosphere Heat Transport,AHT)变化显著相关,但两者变化的原因在两个阶段中是不同的。在快响应阶段,ITCZ位置的移动以及跨赤道AHT受大气层顶(Top of the Atmosphere,TOA)的能量变化驱动,主要与南大洋云短波辐射响应、北半球中高纬度云和地表的短波辐射响应有关,气溶胶减少引起的辐射响应变化使得ITCZ在大多数模式中表现出向北移动的特征。在慢响应下辐射强迫保持稳定,ITCZ在大多数模式中表现出向南移动的特征。这一时期ITCZ的移动由大气表面能量通量变化驱动,主要与潜热通量变化的南北半球差异有关。全球变暖不同阶段ITCZ移动与大气能量输送变化的关系差异反映了海洋对于气候变化的重要调控作用。  相似文献   
996.
邢秀强  贾立华 《海洋工程》2008,26(1):98-102
海水可作为海洋石油平台热泵系统的冷热源,适宜的低温海水也可直接作为空调冷源。海水直接供冷系统可以通过海水变频泵或定流量海水泵抽取不同深度的海水,达到负荷变化的目的。探讨了空调系统中换热器、海水泵、海水输送管道、室内风管等材料的选择问题,提出海洋石油平台空调系统应采用中央空调机组集中送风。为了提高空调系统的可靠性,应采用换热器将海水与热泵机组或空调机组隔离开。  相似文献   
997.
Details are presented of a methodology that utilizes acoustic travel time information in an ocean circulation model. Recent developments of this model-oriented tomography are discussed, representing some significant improvements over earlier formulations. More accurate means of determining the arrival times of specific ray paths are detailed, along with a means of estimating possible errors in the calculated travel times. The assimilation of the observed arrival time information into an ocean model is achieved using a Kalman gain, and more advanced expressions for calculating the Kalman gain are presented. A formulation to account for errors in the stated positions of a source and receiver is also presented. It is shown that the methodology performs fairly well in reproducing observed travel time anomalies. However, the model-predicted anomalies along a specific ray path may not always track the observed anomalies for that path when assimilating multiple ray path data. Results indicate that additional work is required to determine a means of handling observed arrival time data without having prior knowledge of the magnitude of errors in the observations. Results from simulation experiments provide estimates of: (1) potential errors when the travel times for ray paths are only sampled at discreet intervals as opposed to continuously and (2) to what degree acoustic data can be expected to “correct” model-predicted fields.  相似文献   
998.
The role of surface waves in the ocean mixed layer   总被引:7,自引:6,他引:1  
Previously, most ocean circulation models have overlooked the role of the surface waves. As a result, these models have produced insufficient vertical mixing, with an under - prediction of the ,nixing layer (ML) depth and an over - prediction of the sea surface temperature (SST), particularly during the summer season. As the ocean surface layer determines the lower boundary conditions of the atmosphere, this deficiency has severely limited the performance of the coupled ocean - atmospheric models and hence the climate studies. To overcome this shortcoming, a new parameterization for the wave effects in the ML model that will correct this systematic error of insufficient mixing. The new scheme has enabled the mixing layer to deepen, the surface excessive heating to be corrected, and an excellent agreement with observed global climatologic data. The study indicates that the surface waves are essential for ML formation, and that they are the primer drivers of the upper ocean dynamics; therefore, they are critical for climate studies.  相似文献   
999.
The Bering Sea circulation is derived as a variational inverse of hydrographic profiles( temperature and salinity) , atmospheric climatologies and historical observation of ocean curents. The important result of this study is estimate of the mean climatological sea surface height (SSH) that can be used as a reference for satellite altimetry sea level anomaly data in the Bering Sea region. Numerical experiments reveal that, when combined with satellite altimetry, the obtained reference SSH effectively constrains a realistic reconstruction of the Amukta Pass circulation.  相似文献   
1000.
How the role of vertical turbulent mixing (VTM) in sea surface cooling (SSC) varies with the moving speed of a tropical cyclone was examined for Typhoon Rex (1998) by using the Meteorological Research Institute Community Ocean Model (MRI.COM). The MRI.COM well reproduced TRMM/TMI three-day mean sea surface temperature (SST) fields along Rex’s track. During the fast-moving phase of Rex, SSC simulated by the MRI.COM was caused by shear-induced VTM on the right side of the track. During the slowly-moving phase, on the other hand, the Ekman-pumping area mostly overlapped the VTM area right behind Rex’s center. During the recurvature phase, cool water transported by the upwelling was more efficiently entrained into a mixed layer by the VTM for nearly a 1 near-inertial period after the passage of Rex. We then modified the entrainment formulation of Deardorff (1983), which was incorporated into a slab mixed-layer ocean model (SOM) so as to fit to the results simulated by the MRI.COM. The principal modifications are as follows: (1) consideration of turbulent kinetic energy (TKE) production caused by surface wave breaking; (2) increase in the coefficient for estimating dissipation to balance with TKE production due to turbulent transport; and (3) changing the initial guess for the critical Richardson number. These modifications led to an improvement of SST simulations by the SOM. The impact of the modifications on simulated SSTs turned out to be more significant than the impacts of initial mixed-layer depth and the difference between diurnally-varying and daily mean short-wave radiation.  相似文献   
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