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?????й??????????????1992~2005??382??GPS???????????????????????????????????????????????????????????????????仯?????????????????????????????????С?????з?α仯??????:???????72??E??77??E???????????20??1 mm/a?????????77 ??E??82??E???????????12??1 mm/a?????????82??E??92??E?????????????5 mm/a????????????????????????????12 mm/a?????????????????????????????????????82??E???????????????????λ??????????????????Σ????????????????????????????????????????82??E???????????????????????????????????????????????????????????????α??????????????????????????????????Щ?α???????????????????????????С?????????????????????仯????????????????????????????к?????????????????????????????????????????????????Ρ????????????????????????????????????????????????β???????????????????????????????????????????????????????????75??E?????????伷??????17 mm/a???????????????????????????????????75??E???????????????????ε?????????????????????????????     

近30年中国天气预报业务进展

介绍了我国天气预报技术的发展现状，指出在大气探测技术、数值预报及可视化技术发展的推动下我国传统的天气预报向定量、定时方向发展，并系统阐述了天气预报业务发展过程和存在的问题，最后提出了对我国天气预报业务发展的思路。     

714CD雷达资料在短时灾害天气预报中的应用

作者总结了１９９４－１９９６年７１４ＣＤ雷达观测资料在河南省短时生大灾害性天气预报中的应用。着重分析了多普勒速率场上的中尺度天气系统，图像特征以及与短时暴雨，强对流天气的对应，并归纳出短时预报技术流程。     

中国地表植被覆盖变化及其与气候因子关系──基于NOAA时间序列数据分析

本文利用１９８５－１９９０年连续６９个月的ＮＯＡＡ时间序列数据,进行中国植被覆盖变化的空间,以及时间序列分析,并且结合同期的月平均气温、降水数据,进行植被覆盖变化与气候因子相关性分析。该文证实了在中国植被覆盖随时间的推移规律,空间分布规律,以及植被覆盖变化与气温、降水的定量关系。     

热融湖影响下多年冻土退化的数值模拟

在柱坐标下,运用带相变的数值热传导模型,预测了千年尺度上热融湖对多年冻土退化的影响。预测结果表明,受热融湖的影响,湖底下部及周围多年冻土温度状态发生了较大变化。在湖深相同的情况下,湖底年平均温度越高,对多年冻土的热扰动越明显。当湖底年平均温度等于0℃时,湖底下部及周围多年冻土一般不会形成融化层,只可能引起地温升高;当湖底年平均温度大于0℃时,多年冻土不但温度升高,上限下移,而且可能形成融化层,最终导致多年冻土可能被融穿。湖底年平均温度越高,地温增加越快,融穿多年冻土的时间越短。在湖底年平均温度相同的情况下,水深差异对多年冻土退化的影响不明显。     

浅谈MAPGIS的图元参数与属性在地质图制作中的应用

MAPGIS是在地质行业,尤其是在地质图的制作过程中被广泛应用的一种地理信息系统,利用MAPGIS软件制作一张复杂的地质图,其地层颜色的修改和属性的填写是极其繁琐的过程。通过利用点图元、面图元的注释、属性和参数间的关系可以很方便的添写地层颜色,利用投影参数将图元的地理坐标信息方便的挂接为图元的属性,可达到事半功倍的效果。     

High-rate precise point positioning (PPP) to measure seismic wave motions: an experimental comparison of GPS PPP with inertial measurement units

High-rate GPS has been widely used to construct displacement waveforms and to invert for source parameters of earthquakes. Almost all works on internal and external evaluation of high-rate GPS accuracy are based on GPS relative positioning. We build an experimental platform to externally evaluate the accuracy of 50-Hz PPP displacement waveforms. Since the shake table allows motion in any of six degrees of freedom, we install an inertial measurement unit (IMU) to measure the attitude of the platform and transform the IMU displacements into the GPS coordinate system. The experimental results have shown that high-rate PPP can produce absolute horizontal displacement waveforms at the accuracy of 2–4 mm and absolute vertical displacement waveforms at the sub-centimeter level of accuracy within a short period of time. The significance of the experiments indicates that high-rate PPP is capable of detecting absolute seismic displacement waveforms at the same high accuracy as GPS relative positioning techniques, but requires no fixed datum station. We have also found a small scaling error of IMU and a small time offset of misalignment between high-rate PPP and IMU displacement waveforms by comparing the amplitudes of and cross-correlating both the displacement waveforms.     

Terrestrial hydrological responses to precipitation variability in Southwest China with emphasis on drought

Abstract

This study investigates the terrestrial hydrological processes during a dry climate period in Southwest China by analysing the frequency-dependent runoff and soil moisture responses to precipitation variability. Two headwater sub-basins, the Nanpan and Guihe basins of the West River (Xijiang), are studied to compare and contrast the terrestrial responses. The variable infiltration capacity (VIC) model is used to simulate the hydrological processes. Using wavelets, the relationships between observed precipitation and simulated runoff/soil moisture are expressed quantitatively. The results indicate that: (a) the Guihe basin shows a greater degree of high-frequency runoff variability in response to regional precipitation; and (b) the Nanpan basin exhibits less capability in accommodating/smoothing extreme precipitation deficits, reflected in terms of both higher scale-averaged (for 3–6 months) and time-averaged (for the year 1963) wavelet power of soil moisture.

Editor Z.W. Kundzewicz; Associate editor C.-Y. Xu

Citation Niu, J. and Chen, J., 2013. Terrestrial hydrological responses to precipitation variability in Southwest China with emphasis on drought. Hydrological Sciences Journal, 59 (2), 325–335.     

Thermoluminescence in response to the mass extinction event in Penglaitan Section in Laibin,Guangxi

Thermoluminescence(TL)in marine carbonate has been proposed as a potential proxy for reconstruction of paleoceanography history,and has already been used in defining the Quaternary environment.However,its availability in the geological time scale,such as Permian,is still on debate.The mass extinction event caused by drastic changes of global marine environment in Middle-Late Permian provides a typical example to testify the applicability of this proxy.Here we measured the natural thermoluminescence of the carbonate-dominating marine sediments collected from the strata through the Guadalupian-Lopingian mass extinction boundary(G/LB)in the Penglaitan Section in Laibin,Guangxi,China.Our results reveal that TL intensities of carbonate are much higher than those of siliceous rocks,which indicates that the carbonate is the main contributor to the TL.The variation of TL intensities are related with Mn and Fe contents in the carbonate lattices while high Mn and low Fe(e.g.,high Mn/Fe ratio)in carbonate will release stronger TL.Due to the better storage of carbonate lattices for original information of Mn and Fe in seawater,thermoluminescence of carbonate-dominating sediments/rocks could sensitively reflect marine environment and biological productivity in geological time scale.     

沂源县房地产用地情况的调查分析

为推进土地市场化建设，全面准确地分析、评估当前房地产用地形势，沂源县国土资源局组成专项调查队伍，在短时间内对2004，2005年度沂源县辖区内房地产（商业、住宅）开发用地的数量质量、供应管理和投资销售等进行了一次综合性专项调查。调查中主动与建设、规划、计划、统计、房管等有关部门衔接，采取现场实地调研、电话咨询、与购买客户座谈等方式多渠道获取资讯，确保调查数据和调查结果的准确性、完整性。通过调查摸清了沂源县房地产用地市场价格趋势和市场供需状况，为政府宏观调控房地产市场，制定土地供应计划提供了重要依据，对于稳定房地产市场，促进经济社会发展打下了坚实基础。