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71.
To study how the air and sea interact with each other during El Nino/La Nina onsets, extended associate pattern analysis (EAPA) is adopted with the simple ocean data assimilation (SODA) data. The results show that as El Nino/La Nina' s parents their behaviors are quite different, there does not exist a relatively independent tropical atmosphere but does exist a relatively independent tropical Pacific Ocean because the air is heated from the bottom surface instead of the top surface and of much stronger baroclinic instability than the sea and has a very large inter-tropical convergence zone covering the most tropical Pacific Ocean. The idea that it is the wester burst and wind convergence, coming from middle latitudes directly that produce the seawater eastward movement and meridional convergence in the upper levels and result in the typical El Nino sea surface temperature warm signal is confirmed again. 相似文献
72.
A class of coupled system of the E1 Ni(n)o/La Ni(n)a-Southern Oscillation (ENSO) mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behavior of solution for corresponding problem is considered. 相似文献
73.
Observations of the North Equatorial Current,Mindanao Current,and Kuroshio current system during the 2006/07 El Niño and 2007/08 La Niña 总被引:1,自引:0,他引:1
Yuji Kashino Norievill España Fadli Syamsudin Kelvin J. Richards Tommy Jensen Pierre Dutrieux Akio Ishida 《Journal of Oceanography》2009,65(3):325-333
Two onboard observation campaigns were carried out in the western boundary region of the Philippine Sea in December 2006 and January 2008 during the 2006/07 El Niño and the 2007/08 La Niña to observe the North Equatorial Current (NEC), Mindanao Current (MC), and Kuroshio current system. The NEC and MC measured in late 2006 under El Niño conditions were stronger than those measured during early 2008 under La Niña conditions. The opposite was true for the current speed of the Kuroshio, which was stronger in early 2008 than in late 2006. The increase in dynamic height around 8°N, 130°E from December 2006 to January 2008 resulted in a weakening of the NEC and MC. Local wind variability in this region did not appear to contribute to changes in the current system. 相似文献
74.
0716号超强台风“罗莎”是建国以来登陆浙闽交界最晚的一个台风.它经我国台湾岛东北侧打一个圈后登岛,然后在台湾海峡北上,于浙闽交界处登陆,沿温州海岸线缓慢北上后再次入海.“罗莎”的特殊路径一方面与台风附近物理量场分布有关,另一方面可能与全球气候变暖趋势的背景有关.本文分析发现0716号超强台风“罗莎”登陆大陆前后,其附近中低层的物理量场分布对移动路径有密切关系;美国NCEP再分析资料提供的很多物理量如温度、湿度、垂直速度等热力和动力要素对台风未来移动的路径有指示作用;多普勒雷达径向速度演变趋势对台风的短时移动路径预报也有很好的指导意义. 相似文献
75.
????1992??11???2007??5?μ???????????????????????????仯???????????????1???????24~42???μ???????Я???????????ENSO?????2??SLA_2442?????????????????????????????????????????????????????????????????3?????????У????????????SLA_2442?????????·??????O???Σ??????????????,??γ????????λ??????9.86??N??8??S?????? 相似文献
76.
塔里木克拉通东北缘坡北、磁海等地二叠纪幔源岩浆活动形成了镍钴硫化物矿床和铁钴氧化物矿床,两者赋矿镁铁-超镁铁岩体的年龄相近(290~260 Ma),主、微量元素和Sr-Nd-Hf同位素组成相似,分配系数接近的微量元素比值分布于相同趋势线,揭示两者岩浆源区相同,可能为俯冲板片流体交代的亏损地幔或软流圈地幔。两类矿床镁铁-超镁铁质岩中Co与Ni含量正相关,Co主要富集在基性程度高的岩石中;块状硫化物与磁铁矿矿石中Co与Ni相关性差,Co和Ni具有不同的富集机制,Co热液富集作用明显。北山镁铁-超镁铁杂岩体是地幔柱相关软流圈上涌,诱发俯冲板片交代的亏损岩石圈地幔发生部分熔融,形成的高镁母岩浆演化过程中经历壳源混染、硫化物饱和富集镍钴形成铜镍钴硫化物矿床,富铁母岩浆氧逸度高、富水,岩浆分离结晶磁铁矿、叠加热液作用富集钴,形成铁钴氧化物矿床。 相似文献
77.
Abstract El Niño Southern Oscillation (ENSO) has been linked to climate anomalies throughout the world. This paper presents an overview of global ENSO-streamflow teleconnection and identifies regions where the relationship may be exploited to forecast streamflow several months ahead. The teleconnection is investigated by fitting a first harmonic to 24-month El Niño streamflow composites from 581 catchments worldwide and the potential for forecasting is investigated by calculating the lag correlation between streamflow and two indicators of ENSO. The analyses indicate clear ENSO-streamflow teleconnections in many catchments, some of which are consistent across large geographical regions. Strong and regionally consistent ENSO-streamflow teleconnections are identified in Australia and New Zealand, South and Central America, and weaker signals are identified in some parts of Africa and North America. The results suggest that the ENSO-streamflow relationship and the serial correlation in streamflow can be used to successfully forecast streamflow. The streamflow forecasts can be used to help manage water resources, particularly in systems with high interannual variability in Australia, southern and drier parts of Africa and some areas of North America. 相似文献
78.
Boon-khean Cheang 《Journal of Earth System Science》1993,102(1):219-239
Interannual variations of the monsoons have been studied utilising homogeneous rainfall records of 41 years (1951–1991) from
Malaysia and upper air data of stations in Asia, Australia and Western Pacific. Sources of upper air data are U.S. Department
of Commerce and Kuala Lumpur Northern Winter Monsoon Activity Centre. Extreme wet and dry years have been identified and the
influence of ENSO on Malaysian annual rainfall has been discussed. Influence of ENSO on the performance of northern summer
and winter monsoons has also been studied from Malaysian rainfall data. Further, regional circulation patterns associated
with El Nino and La Nina years have also been identified. No linear trend has been found in the annual rainfall of 16 stations
in Malaysia. Most El Nino years are associated with below median and La Nina years with above median rainfall at most stations
in Malaysia. ENSO has greater influence over East Malaysia than peninsular Malaysia. Interannual variability of rainfall with
reference to ENSO conditions has been discussed in details. Also, circulation features have been identified to foresee El
Nino/La Nina events. 相似文献
79.
80.
分析1951年以来苏州夏季高温以及持续高温与厄尔尼诺、亚洲经向环流指数、副高强度指数的关系,1992年夏季根据GMS卫星云图所反应的厄尔尼诺状况和其他因素,对日本96-192小时的数值预报进行修正,准确及时地作出了持续高温的中期预报。 相似文献