2007年7月江淮流域降水过程云分辨尺度模拟研究——数值模拟及验证

利用美国Goddard中心的云分辨尺度模式,对2007年7月2—9日江淮流域的一次暴雨过程进行了高分辨率的模拟研究。首先利用NCAR/NCEP再分析资料、地面降水观测以及卫星云图等常规和非常规观测资料,对此次降水过程开展了天气尺度分析,对过程降水特点有了初步了解;进而利用NCAR/NCEP再分析资料形成云模式大尺度强迫场,对降水过程开展了长度约8天的高分辨率数值模拟。通过观测与模拟的地面雨强以及雷达反射率等的对比分析发现,模式很好地模拟出了此次强降水过程的时空分布和演变特征,以及主要的雷达回波结构特点,模拟结果可用于进一步针对江淮流域地面强降水过程细致的定量诊断分析研究。     

阿克苏河流域无站控制区地表水资源及可利用量评价

阿克苏河是"四源一干"中最大的源流,多年平均地表径流总量为80.6×108m3,入塔里木河水量34.2×108m3,占阿拉尔站以上3条源流输水量的73.5%,对塔里木河的形成、发展、演变和生态环境起着决定作用.无站控制区调查面积7 110 km2,占流域总面积的14.2%.2005—2007年对中国境内阿克苏河无站控制区主要19条河(沟)洪水水量、洪水沟基流和17条泉水水量野外调查计算,阿克苏河流域无站控制区间地表水资源总量为6.68×108m3.其中,洪水沟总洪量0.6050×108m3,洪水沟基流总量2.0569×108m3,泉水天然补给量4.0185×108m3.在6.68×108m3的地表水资源总量中,可利用量为3.2×108m3.     

印度喜马拉雅山区流域的冰川资源及其冰冻圈研究计划

<正>印度喜马拉雅山区流域17%的面积被永久性积雪和冰川覆盖,大约有32000km2,其中,冰川共计在9000条以上,储存了大约12000km3的淡水资源.这些冰川对维持区域生态的稳定和调节河流径流供水具有重要意义.各流域的冰川分     

海河流域近50年水文要素变化分析

海河流域水文要素的变化受气候变化和人类活动的共同影响.采用Mann-Kendall检验方法和滑动t检验方法对海河流域近50年水文要素的变化趋势及变异年份进行了分析和讨论.结果表明海河流域整体呈现暖干气候倾向.气温存在显著升高趋势,蒸发皿蒸发量平原区大多存在显著下降趋势,降水量全流域整体呈现不显著减少趋势.气温增温变点大致出现在1988～1992年左右.蒸发皿蒸发量和降水量变化趋势为先减少后增加.减少变点一般出现在70年代末80年代初,增加变点分别出现在1992年左右和1987～1989年左右.经济发展和城市化进程较早的北京气温和蒸发皿蒸发量的变点较为提前.     

清河流域水文特性简析

采用清河流域4个水文站及9个雨量站几十年的水文资料,利用水文统计分析方法,分析了清河流域降水、径流、泥沙、蒸发水文特征,为合理开发、利用清河流域水资源,解决环境及水资源短缺问题,提供分析依据。     

开都河流域区径流时空分布特征分析

开都河流域位于新疆天山山脉中段南坡,塔里木盆地北缘。河流上游穿越了天山山地的大、小尤勒都斯山问盆地;河流中游经高山峡谷段,汇入几条较大支流的水量;河流下游汇纳莫合茶汗沟、哈合仁郭楞沟及黄水沟西支的部分水量．是新疆水量较大的河流之一。本文选取该河流域巴音布鲁克、山恨土海、大山口、黄水沟、焉耆水文站的径流资料。运用数理统计的方法对流域内水文要素时空变化特征进行分析,分析结果表明,开都河流域径流量年内分配不均,但年际变化不大,产水模数与流域控制高度关系密切;流域下游,随着流域人口的增加和社会经济的发展,区间引用水和消耗水量呈增加的趋势。     

Study on the geochemical correlation of crude oils of Palaeocene and Jurassic ages from the Potowar Indus Basin in northern Pakistan

This study deals with a detailed geochemical characterization of three crude oils from the Upper Indus Basin, Punjab, Pakistan. The samples were obtained from three productive oil fields of the Datta Formation (Jurassic), Lochhart (Palaeocene) and the Dhak Pass zone (Palaeocene). The GC parameters for and the bulk properties of Datta Formation oils are essentially coincident with those of the oils from the Dhak Pass Formation in the Upper Indus Basin, Pakistan and the oils likely originate from a marine source rock. In contrast, the Lockhart Formation oils show different behaviors and seem to be originated from dirty carbonate rocks although all three crude oils are mature, being of non-biodegraded and somewhat mixed organic matter origin. Low Pr/Ph values and high C₃₅ homohopane index for the Lockhart Formation oils suggest a source of anoxic environment with low Eh while oils from the Datta Formation and Dhak Pass Formation showed different trends, i.e., lower values of C₃₅ homohopane index indicating different depositional environment than oil from the Lockhart Formation. All three crude oils from the Upper Indus Basin are mature for the hopane ratios, i.e., Ts/Ts+Tm, C₃₂22S/(S+R) and C₃₀ αβ/(αβ+βα) and sterane ratios, i.e., C₂₉22S/(S+R) and C₂₉ββ/(ββ+αα) but oils from the Lockhart Formation seem to be less mature than those from the Palaeocene and Datta Formation according to plots like API° vs. homohopane Index, Pr/Ph vs. sterane. The relative composition of 5α(H), 14β(H), 17β(H)-24-ethylecholestanes and the C₂₉20S/20S+20R index, indicate that all three crude oils are equally mature, which makes it unlikely with respect to the above said plots. This difference is may be due to the migratory chromatography which alters the concentrations of sterane and hoapnes and hence gives different results. These oils do not exhibit UCM and have complete n-alkane profiles indicating non-biodegradation.     

青藏高原东部金沙江流域盆地陆地风化特征

青藏高原东部金沙江流域是研究高原隆升与陆地风化的理想地区。本文通过对金沙江河流系统的取样,从河流溶质载荷主要离子和悬浮载荷粘土矿物等方面揭示青藏高原东部金沙江流域盆地陆地风化特征。研究表明,金沙江流域盆地陆地岩石风化主要是碳酸盐岩、蒸发盐岩和硅酸盐岩。利用S i、S i/TZ+*、S i/Na*+K和S i/K以及(Na*+K)/TZ+等5个指标结合流域区域岩石分布和土壤特征揭示出流域硅酸盐岩为浅表性初级风化,风化产物主要是富含阳离子的次生粘土矿物。     

Spatiotemporal Modeling of Monthly Precipitation in the Upper Shiyang River Watershed in West Central Gansu, Northwest China

This paper outlines a methodology to estimate monthly precipitation surfaces at 1-km resolution for the Upper Shiyang River watershed(USRW) in northwest China.Generation of precipitation maps is based on the application of a four-variable genetic algorithm(GA) trained on 10 years of weather and ancillary data,i.e.,surface air temperature,relative humidity,Digital Elevation Model-derived estimates of elevation,and time of year collected at 29 weather stations in west-central Gansu and northern Qinghai provin...