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11.
为提升对山西省地下流体观测井承压性的进一步认识,以位于该省北、中、南部的朔州井、静乐井、祁县井、洪洞井和东郭井为研究对象,选取水位、气压观测数据,并利用井水位的理论固体潮数据,分别对井水位进行气压的阶跃响应函数计算、FFT频谱和潮汐相位响应分析,综合判定地下流体观测井—含水层类型,结果表明,5口观测井地下水埋藏类型均为半承压水。  相似文献   
12.
汶川地震农居震害特征及其成因分析与恢复重建建议   总被引:3,自引:2,他引:1  
本文总结了汶川地震中农居倒塌、严重破坏与中等破坏的特点,并分析了破坏程度与地震动、地震地表破裂、滑坡、滚石和房屋质量等因素的关系。为了减轻未来地震造成的震害,城镇选址应避开危险地段和抗震不利地段,且农居设计与施工应严格遵循抗震设计规范中的相关条款。同时,本文也强调了当地政府在灾区重建中的重要作用。  相似文献   
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14.
降水量在时间分布上呈现较大的随机性,极端降水事件尤为如此。受此影响,月初(月末) 1~5 d之内的累积降水量很可能会超过当月总降水量的50%乃至更多。对1961—2017年中国2 400多站点资料统计分析结果发现,月初(月末) 1~5 d累积降水量对当月总降水量显著影响事件的出现频次,在季节和空间分布上都有鲜明特征。主要包括:1)月初累积降水量对秋冬季中各月的总降水量影响更大,月末累积降水量对1—4月的月总降水量影响较大。2)受月初累积降水量的影响,显著站点数在某些年份的某些月份出现极大值;受单次事件显著影响的站点数占全国总站点数的30%~50%,此即对应着一次全国大范围的极端降水事件。3)受月初(月末)累积降水量显著影响的站点空间分布随季节变化呈现出明显空间集聚特征。  相似文献   
15.
Climate sensitivity and feedbacks are basic and important metrics to a climate system. They determine how large surface air temperature will increase under CO_2 forcing ultimately, which is essential for carbon reduction policies to achieve a specific warming target. In this study, these metrics are analyzed in a climate system model newly developed by the Chinese Academy of Meteorological Sciences(CAMS-CSM) and compared with multi-model results from the Coupled Model Comparison Project phase 5(CMIP5). Based on two idealized CO_2 forcing scenarios, i.e.,abruptly quadrupled CO_2 and CO_2 increasing 1% per year, the equilibrium climate sensitivity(ECS) and transient climate response(TCR) in CAMS-CSM are estimated to be about 2.27 and 1.88 K, respectively. The ECS is near the lower bound of CMIP5 models whereas the TCR is closer to the multi-model ensemble mean(MME) of CMIP5 due to compensation of a relatively low ocean heat uptake(OHU) efficiency. The low ECS is caused by an unusually negative climate feedback in CAMS-CSM, which is attributed to cloud shortwave feedback(λSWCL) over the tropical Indo-Pacific Ocean.The CMIP5 ensemble shows that more negative λSWCL is related to larger increase in low-level(925–700 hPa)cloud over the tropical Indo-Pacific under warming, which can explain about 90% of λSWCL in CAMS-CSM. Static stability of planetary boundary layer in the pre-industrial simulation is a critical factor controlling the low-cloud response and λSWCL across the CMIP5 models and CAMS-CSM. Evidently, weak stability in CAMS-CSM favors lowcloud formation under warming due to increased low-level convergence and relative humidity, with the help of enhanced evaporation from the warming tropical Pacific. Consequently, cloud liquid water increases, amplifying cloud albedo, and eventually contributing to the unusually negative λSWCL and low ECS in CAMS-CSM. Moreover, the OHU may influence climate feedbacks and then the ECS by modulating regional sea surface temperature responses.  相似文献   
16.
回忆侯德封先生在野外工作时认真负责的工作态度和工作作风。他的求实精神和活跃的学术思想是我学习的榜样  相似文献   
17.
The Chinese Academy of Meteorological Sciences (CAMS) has been devoted to developing a climate system model (CSM) to meet demand for climate simulation and prediction for the East Asian region. In this study, we evaluated the performance of CAMS-CSM in regard to sensible heat flux (H), latent heat flux (LE), surface temperature, soil moisture, and snow depth, focusing on the Atmospheric Model Intercomparison Project experiment, with the aim of participating in the Coupled Model Intercomparison Project phase 6. We systematically assessed the simulation results achieved by CAMS-CSM for these variables against various reference products and ground observations, including the FLUXNET model tree ensembles H and LE data, Climate Prediction Center soil moisture data, snow depth climatology data, and Chinese ground observations of snow depth and winter surface temperature. We compared these results with data from the ECMWF Interim reanalysis (ERA-Interim) and Global Land Data Assimilation System (GLDAS). Our results indicated that CAMS-CSM simulations were better than or comparable to ERAInterim reanalysis for snow depth and winter surface temperature at regional scales, but slightly worse when simulating total column soil moisture. The root-mean-square differences of H in CAMS-CSM were all greater than those from the ERA-Interim reanalysis, but less than or comparable to those from GLDAS. The spatial correlations for H in CAMS-CSM were the lowest in nearly all regions, except for North America. CAMS-CSM LE produced the lowest bias in Siberia, North America, and South America, but with the lowest spatial correlation coefficients. Therefore, there are still scopes for improving H and LE simulations in CAMS-CSM, particularly for LE.  相似文献   
18.
汶川8.0级地震滑坡、崩塌机制   总被引:6,自引:0,他引:6  
本文总结了汶川8.0级地震引起的滑坡、崩塌的破坏特征,分析了地震地质灾害的外因和内因。鉴于本次地震导致的大量人员伤亡和巨大的财产损失,在进行城镇灾后重建工作或类似山区城镇规划时,强烈建议进行地震地质灾害评估工作。  相似文献   
19.
辽宁省生态足迹地理分布及其可持续发展分析   总被引:9,自引:1,他引:8  
This paper presents the detailed results and analyses on the ecological footprints and bio-capacities of the individual cities and the province as a whole for the year 2001, providing a clear picture of sustainability for the province. Results show that the ecological footprints of most cities in Liaoning exceeded their respective bio-capacities, incurring high ecological deficits. The ecological deficit of the province as a whole was 1.31 ha/cap. Those cities with resources extraction and/or primary material-making as their major industries constitute the “ecologically black band“, whose ecological deficits ranged from 2.45 to 5.23 ha/cap, the highest of all cities in the province. Fossil energy consumption was the major source of footprint amounting to 1.63 ha/cap at the provincial level,taking up 67.3% of the total. For cropland, modest ecological surpluses occurred in Jinzhou, Tiding,Huludao, and Panjin while modest ecological deficits in Dalian, Benxi, Fushun, and Dandong, resulting in an overall surplus for the province. Liaoning had a certain level of surplus in fishing ground (water area), mainly distributed in the coastal cities of Dalian, Panjin, Huludao, Yingkou, Jinzhou, and Dandong. Most cities had a small ecological deficit in pasture and all had a small ecological surplus in forest. The eco-efficiency, expressed as GDP value per hectare of footprint, exhibits high variations among the cities, with the highest (Shenyang) more than 10 times the lowest (Fuxin). Cities with manufacture, high-tech, and better developed service industries had high eco-efficiency, while those with resources extraction, primary material-making, and less developed service industries had low eco-efficiency. Based on the components and geographical distribution of ecological footprint, strategic policy implications are outlined for Liaoning‘s development toward a sustainable future.  相似文献   
20.
输电线路常需要跨越地质灾害易发区域,为了保证电力的正常、安全输送,对输电线路通道所经区域进行滑坡地质灾害的空间分布及潜在风险评价具有重要意义。本文结合GIS和AHP方法进行了某输电线通道滑坡灾害危险性评价,选取地形地貌、气候条件、水文条件、人为活动条件、植被条件、地质岩组条件等影响因子,建立评价指标体系,利用层次分析法(AHP)确定各因子权重,基于GIS地理空间分析评价了输电线路通道地质灾害危险性,划分了5类区域:极高危险区、高危险区、中危险区、低危险区、较低危险区。危险性评价结果可为输电线路电力设施通道滑坡灾害防治、安全设计和施工提供科学依据。  相似文献   
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