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771.
772.
To investigate the feasibility and methodology of new generation sea surface temperature (SST) maps that combine various satellite
measurements, we have quantitatively evaluated SST availabilities of NOAA AVHRR (National Oceanic and Atmospheric Administration,
Advanced Very High Resolution Radiometer), GMS S-VISSR (Geostationary Meteorological Satellite, Stretched-Visible Infrared
Spin Scan Radiometer) and TRMM MI (Tropical Rainfall Measuring Mission, Microwave Imager: TMI), during the one-year period
from October 1999 to September 2000. The advantage of satellite microwave SST measurements is the ability to penetrate the
clouds that contaminate satellite infrared measurements. Daily SST availabilities were calculated in the overlapping coverage
from 20°N to 38°N and 120°E to 160°E. The annual-mean SST availabilities of AVHRR, S-VISSR and TMI are 48%, 56% and 78%, respectively.
There are large seasonal variations in the availabilities of infrared measurements. The latitude-time plots of one-degree
zonal mean SST availabilities of S-VISSR and TMI in the region from 38°S to 38°N and 80°E to 160°W show significant zonal
variations, which are influenced by the atmospheric circulation such as the Subtropical High and the Intertropical Convergence
Zone. The SST availabilities of S-VISSR and TMI in the five selected regions have large regional variations, ranging from
35% to 74% and 62% to 88% for S-VISSR and TMI, respectively. The present statistical analyses of SST availabilities in the
infrared and microwave measurements indicate that 1) a daily cloud-free high-spatial resolution may be achieved by merging
various SST measurements since their deficiencies compensate each other, and 2) nevertheless, it is necessary to take account
of the seasonal and regional variations of SST availabilities of different satellite sensors for the development of merging
technology.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
773.
774.
Merging satellite infrared and microwave SSTs: Methodology and evaluation of the new SST 总被引:3,自引:0,他引:3
The Global Ocean Data Assimilation Experiment (GODAE) requires the availability of a global analyzed SST field with high-resolution
in space (at least 10 km) and time (at least 24 hours). The new generation SST products would be based on the merging of SSTs
from various satellites data and in situ measurements. The merging of satellite infrared and microwave SST data is investigated in this paper. After pre-processing
of the individual satellite data, objective analysis was applied to merge the SST data from NOAA AVHRR (National Oceanic and
Atmospheric Administration, Advanced Very High Resolution Radiometer), GMS S-VISSR (Geostationary Meteorological Satellite,
Stretched-Visible Infrared Spin Scan Radiometer), TRMM MI (Tropical Rainfall Measuring Mission, Microwave Imager: TMI) and
VIRS (Visible and Infrared Scanner). The 0.05° daily cloud-free SST products were generated in three regions, viz., the Kuroshio
region, the Asia-Pacific Region and the Pacific, during one-year period of October 1999 to September 2000. Comparisons of
the merged SSTs with Japan Meteorological Agency (JMA) buoy SSTs show that, with considerable error sources from individual
satellite data and merging procedure, an accuracy of 0.95 K is achieved. The results demonstrate the practicality and advantages
of merging SST measurements from various satellite sensors. 相似文献
775.
1945~2006年东中国海海表温度的长期变化趋势 总被引:8,自引:0,他引:8
通过对HadISST1资料1945~2006年海表温度(SST)的分析,发现在东中国海SST具有明显的长期升高的线性变化趋势,平均每年升高0.015℃,在这62 a共升高了0.9℃.其中,东海的升温现象最为突出,从福建和浙江两省沿岸向东北方向扩展的大片海域,是整个东中国海SST变化最大的所在.由于台湾海峡常年向北的流动和台湾岛东北侧向北的黑潮水入侵在1945~2006之间得到了相当程度的加强,它们对热量平流输运的增加有利于东中国海SST长期升高.同样起到促进作用的还有海面风场所控制的垂向卷夹过程.海面净热通量的变化抑制了东中国海SST的长期升高趋势.研究结果显示,东中国海SST的长期变化趋势极有可能是受到太平洋长期变化的影响. 相似文献
776.
777.
采用合成分析原理,研究了山东夏季降水不同分布型的前期冬、春季大气环流及前期秋、冬、春季海温场特征。结果表明,不同降水分布型在前期的大气环流及海温场中表现出了较大差异,同多型表现为欧亚中高纬环流由前冬12月的纬向型,隆冬到初春转为经向型,西太平洋副高隆冬到初春偏弱,春季4—5月转为偏强,海温场则表现为赤道中东太平洋地区前期秋冬季的暖水位相到春季减弱或转换为冷水位相;而同少型则基本相反;东多西少型前期冬春季西太平洋副高持续偏弱,欧亚中高纬和北美地区盛行经向环流,海温场上则表现为从上年秋冬季为拉尼娜状态,而春季明显减弱;西多东少型基本相反。 相似文献
778.
利用NCEP/NCAR的再分析资料、全球海温资料(OISST)及区域气候模式(RegCM3)研究了东亚夏季低层(925hPa)大气环流对东海及其邻近海域热力异常的响应.结果表明,夏季,当东海及其邻近海域的海温升高0.5和1.0℃时,在中国东部和东海及其邻近海域上空均会出现一个异常的气旋性环流,而且海温越高,气旋性环流越明显,并在海面上空形成辐合中心;反之,当东海及其邻近海域海温降低时,中国东部和东海及其邻近海域上空将出现一个异常的反气旋性环流,并在海面上空形成辐散中心.东海及其邻近海域夏季海温的异常可通过热力作用影响低层大气的辐合(散)和垂向运动,并影响局地低层大气和上层海洋的相互作用,从而使得东亚大气环流发生改变,进而可能对中国大陆东部气候和近海环境的变化产生重要作用. 相似文献
779.
Coastal upwelling phenomenon along the China coast in the Yellow Sea during August 2007 is studied using ENVISAT Advanced
Synthetic Aperture Radar (ASAR) data, NOAA Advanced AVHRR series Sea Surface Temperature (SST) data, and NASA QuikSCAT Scatterometer
ocean surface wind data. A dark pattern in an ASAR image is interpreted as coastal upwelling. This is because the natural
biogenic slicks associated with coastal upwelling damp the Bragg waves on the sea surface and thus make the surface smoother.
Most of the incoming radar energy is reflected in the forward direction. As a result, the radar backscatter signal is very
weak. Analyzing the concurrent AVHRR SST image, we find that the dark pattern in the ASAR image is indeed corresponding to
the low SST area. The wind retrieval in the slicks dominant region is biased due to the low Normalised Radar Cross Section
(NRCS) associated with the coastal upwelling. We applied a SST correction to the NRCS values to improve the accuracy of wind
retrieval from ASAR data. 相似文献
780.