东亚活动中心与我国水旱灾的关系   总被引：1，自引：0，他引：1  

涂长望 《气象学报》1936,12(11):600-619

民国二十年的大水和二十三年的大旱是近百年来罕有的现象。这两次浩劫不单给与国人之生命财产以重大创伤,同时也成功了中国气象研究上最感迫切的中心问题。关於这两次水旱钜灾刘治华朱炳海,两先生曾先後撰文阐明了致灾的天气因素和原理。当时因收集国外气象材料颇费时日,他们的敍述就不得不偏重於国内的天气情形,不过在讨论中他们也曾顾及到东亚天气的影响,尤其是日本海的  相似文献   

中国气候区域   总被引：2，自引：0，他引：2  

涂长望  卢鋈 《气象学报》1936,12(9):487-518

中国气候区域分划之演进,要可分为二期,即寇本(Koeppen)期与竺可桢期是也。寇本时期,对于世界气候之分类,以方法单纯,系统一律为其特色。寇本马东男(Emma de Mortonne)及希孟(J.Sion)三氏,无论分割全世界之气候区域,或一洲之气候区域,均取同一标准。其所采标准既普遍化,结果遂优劣互见。此种分类法最大之缺点,即在忽略足以使一地气候自成一类之重要气象因素。因此,  相似文献   

The research on the adsorption effect on metal ions by immobilized marine algae   总被引：3，自引：0，他引：3  

WANG Xian  QIU Haiyuan  CAI Zhenzhen  CHEN Lidan  ZHENG Shenghu  HUANG Zhiwei 《海洋学报(英文版)》2006,25(2):153-158

1 IntroductionBiosorption is a processthatutilizes biomasstoabsorb heavy metalsand isparticularly usefulfortheremoval of contam inants from industrial effluents.Inartificialorganism scannotbe used in practicalpro-ductionbecauseoftheirlow density,low inten…  相似文献   

黄海西部34°N断面潮生陆架锋的多年变化及跨锋断面的环流结构   总被引：5，自引：0，他引：5  

赵保仁  涂登志  毕亚文 《海洋科学》1992,16(2):41-45

本文分析了苏北浅滩外侧34°N断面上潮生陆架锋的多年变化,指出海上调查期间的日平均风速和大小潮变化是影响陆架锋多年变化的主要因素。本文还用诊断模式给出了横跨锋断面的环流结构。  相似文献   

油菜花最佳观赏期变化及其对温度因子的响应     

张志薇  高苹  王宏斌  艾文文  孙家清  鲍婧  徐敏 《气象》2019,45(5):667-675

气温是各种气候因子中影响植物花期迟早最重要的因素之一。以高淳油菜花为研究对象,选取近30年(1986—2016年)物候观测资料,分析了盛花期的变化特征和盛花期早晚年温度因子的特征;采用通径分析法,研究分析了三个表征温度的指标(平均气温T_a5℃的日数、积温和强冷空气日数)与油菜花盛花期关系,结果为预测高淳油菜花的最佳观赏期、做好相关旅游气象服务提供了理论依据。结果表明:高淳油菜花盛花期在2001年以前波动不大,但在2001年后,随年代际呈提早趋势;盛花期迟早年类型不同,T_a稳定在5℃的日期也有差别,具体为盛花期偏早年正常偏早年和正常偏晚年正常年偏晚年;盛花期偏晚年与T_a5℃的日数和积温关系也很显著,从冬至日开始,若T_a5℃的日数超过了53 d或者T_a5℃的积温超过137℃·d,则翌年油菜花盛花日期有可能出现在4月4日之后;若达到强冷空气级别的日数越多,则翌年高淳油菜花盛花期会有所推后。在三个表征温度的指标中,对油菜花盛花期影响最大的是T_a5℃积温。  相似文献   

多视线向D-InSAR三维地表形变解算中GPS约束定权     

王志伟  刘国林  陶秋香  于胜文  王珂  周传义 《测绘通报》2018,(8):6-10

提出了一种基于GPS约束的多视线向三维地表形变解算定权的方法。该方法以同期高精度GPS形变观测量对多视线向D-In SAR形变观测量进行精度评价,顾及轨道、地形和噪声等系统误差对多视线向D-In SAR形变量影响的特点,通过建立跟像元位置和高程有关的联合拟合模型,实现逐像元精度评价,完成多视线向D-In SAR三维地表形变解算模型中定权。本文以2009年意大利拉奎拉地区地震为研究区,对该定权方法的可行性和精度进行了验证。结果表明,本文提出的GPS约束定权的多视线向D-In SAR三维形变解算方法可以获取可靠的解算结果。  相似文献   

Deriving time-series three-dimensional displacements of mining areas from a single-geometry InSAR dataset   总被引：1，自引：0，他引：1  

Zefa Yang  Zhiwei Li  Jianjun Zhu  Guangcai Feng  Qijie Wang  Jun Hu  Changcheng Wang 《Journal of Geodesy》2018,92(5):529-544

This paper presents a method for deriving time-series three-dimensional (3-D) displacements of mining areas from a single-geometry interferometric synthetic aperture radar (InSAR) dataset (hereafter referred to as the SGI-based method). This is mainly aimed at overcoming the limitation of the traditional multi-temporal InSAR techniques that require SAR data from at least three significantly different imaging geometries to fully retrieve time-series 3-D displacements of mining areas. The SGI-based method first generates the multi-temporal observations of the mining-induced vertical subsidence from the single-geometry InSAR data, using a previously developed method for retrieving 3-D mining-related displacements from a single InSAR pair (SIP). The weighted least-squares solutions of the time series of vertical subsidence are estimated from these generated multi-temporal observations of vertical subsidence. Finally, the time series of horizontal motions in the east and north directions are estimated using the proportional relationship between the horizontal motion and the subsidence gradient of the mining area, on the basis of the SGI-derived time series of vertical subsidence. Seven ascending ALOS PALSAR images from the Datong mining area of China were used to test the proposed SGI-based method. The results suggest that the SGI-based method is effective. The SGI-based method not only extends the SIP-based method to time-series 3-D displacement retrieval from a single-geometry InSAR dataset, but also limits the uncertainty propagation from InSAR-derived deformation to the estimated 3-D displacements.  相似文献   

Stochastic modeling for time series InSAR: with emphasis on atmospheric effects     

Yunmeng Cao  Zhiwei Li  Jianchao Wei  Jun Hu  Meng Duan  Guangcai Feng 《Journal of Geodesy》2018,92(2):185-204

Despite the many applications of time series interferometric synthetic aperture radar (TS-InSAR) techniques in geophysical problems, error analysis and assessment have been largely overlooked. Tropospheric propagation error is still the dominant error source of InSAR observations. However, the spatiotemporal variation of atmospheric effects is seldom considered in the present standard TS-InSAR techniques, such as persistent scatterer interferometry and small baseline subset interferometry. The failure to consider the stochastic properties of atmospheric effects not only affects the accuracy of the estimators, but also makes it difficult to assess the uncertainty of the final geophysical results. To address this issue, this paper proposes a network-based variance–covariance estimation method to model the spatiotemporal variation of tropospheric signals, and to estimate the temporal variance–covariance matrix of TS-InSAR observations. The constructed stochastic model is then incorporated into the TS-InSAR estimators both for parameters (e.g., deformation velocity, topography residual) estimation and uncertainty assessment. It is an incremental and positive improvement to the traditional weighted least squares methods to solve the multitemporal InSAR time series. The performance of the proposed method is validated by using both simulated and real datasets.  相似文献   

地质岩芯科技资源科普化工作探索与实践——以自然资源实物地质资料中心为例     

张志伟  刘文卿  袁野  高建伟  苏桂芬 《地质论评》2023,69(4):2023040026-2023040026

岩芯科技资源科普化是打通地质科研—科普链条的重要途径,本文通过梳理我国岩芯科技资源现状,分析了岩芯科技资源科普化的现实意义,重点阐述了岩芯科技资源在向地质科普转化5个方面的探索与实践,提出了今后岩芯科技资源科普化工作应建立良好政策机制制度、转变科研人员观念、科技知识向科普转化水平、新技术新手段的应用以及做好科普活动的实施总结等5项工作建议。  相似文献   

多系统GNSS卫星可见性全球时空变化分析     

刘志伟  江鹏 《测绘工程》2018,(9):26-29,34

多系统GNSS卫星组合定位成为导航系统发展的重要趋势。基于武汉大学IGS数据中心发布的精密星历,以可见卫星数及PDOP为研究对象,通过地面点仿真实验,分析多系统GNSS卫星在全球范围内可见性的时空变化,比较多系统GNSS相较单系统在卫星分布上的优势。结果表明,对于地面固定点,各GNSS系统卫星可见性的重复周期都约为24h,其中GPS/BDS/GLONASS/Galileo 4系统的卫星可见性稳定性最高,单GPS系统较差;相较于GPS单系统,GPS/BDS双系统在亚太地区的可见卫星数由7~13颗提高到15~23颗,而GPS/BDS/GLONASS/Galileo 4系统在欧亚和亚太地区的可见卫星数提高到24~30颗。  相似文献