Deconvolving the δO seawater component from subseasonal coral δO and Sr/Ca at Rarotonga in the southwestern subtropical Pacific for the period 1726 to 1997

To reconstruct oceanographic variations in the subtropical South Pacific, 271-year long subseasonal time series of Sr/Ca and δ¹⁸O were generated from a coral growing at Rarotonga (21.5°S, 159.5°W). In this case, coral Sr/Ca appears to be an excellent proxy for sea surface temperature (SST) and coral δ¹⁸O is a function of both SST and seawater δ¹⁸O composition (δ¹⁸O_sw). Here, we focus on extracting the δ¹⁸O_sw signal from these proxy records. A method is presented assuming that coral Sr/Ca is solely a function of SST and that coral δ¹⁸O is a function of both SST and δ¹⁸O_sw. This method separates the effects of δ¹⁸O_sw from SST by breaking the instantaneous changes of coral δ¹⁸O into separate contributions by instantaneous SST and δ¹⁸O_sw changes, respectively. The results show that on average δ¹⁸O_sw at Rarotonga explains ∼39% of the variance in δ¹⁸O and that variations in SST explains the remaining ∼61% of δ¹⁸O variance. Reconstructed δ¹⁸O_sw shows systematic increases in summer months (December-February) consistent with the regional pattern of variations in precipitation and evaporation. The δ¹⁸O_sw also shows a positive linear correlation with satellite-derived estimated salinity for the period 1980 to 1997 (r = 0.72). This linear correlation between reconstructed δ¹⁸O_sw and salinity makes it possible to use the reconstructed δ¹⁸O_sw to estimate the past interannual and decadal salinity changes in this region. Comparisons of coral δ¹⁸O and δ¹⁸O_sw at Rarotonga with the Pacific decadal oscillation index suggest that the decadal and interdecadal salinity and SST variability at Rarotonga appears to be related to basin-scale decadal variability in the Pacific.     

HUBEX强化观测期雷达测雨在水文过程模拟中的应用(英)

选择全球能量与水循环亚洲季风试验区的淮河黄泥庄水文站控制的史河流域(805 km2)为研究区域,基于数字高程模型,生成栅格水流流向,构建数字流域及空间拓扑关系;然后,将阜阳雷达观测数据经过订正校准后作为研究区内每一栅格单元上的雨量输入,并在每一栅格上应用新安江模型构建产流模型;再根据每一栅格至流域出口断面-黄泥庄水文站的距离,运用Muskingum方法进行汇流演算,从而获得黄泥庄站的流量过程。计算结果显示,从1998年5月31日-8月3日的强化观测期内模型确定性系数为92.41％,其间4场洪水的确定性系数分别为85.64％、86.62％、92.57％和83.91％,高于应用地面雨量计观测的数据计算的结果。这说明雷达测雨数据具有较高的时空分辨率,当它应用于水文过程模拟时优于地面雨量计资料,基于栅格的水文模型为充分利用雷达数据提供了良好平台。     

长白山天池火山区长白-敦化剖面结晶基底的探测和研究

时间项分析法中，应用广义最小二乘法进行反演，对长白山天池火山区岩浆系统的长白—敦化(L1)剖面的Pg波到时进行了计算处理，得到了Pg波时间项及基底速度值；取上部地壳的介质平均速度为4．5km/s，经反演求得了各点的深度值，给出了长白山天池火山区结晶基底的厚度分布。结晶基底厚度一般在2．0km左右，而在长白山天池下方结晶基底最厚处接近4．0km；在万宝和敦化附近各有一不太明显的凹陷，其原因可能与在这两个位置处有几条断裂穿过有关。     

河南省短期区域性暴雨动力诊断及综合预报方案

介介绍了（１）用Ｔ６３数值预报产品对河南省省６－８月区域性暴雨进行物理量诊断分析。（２）用人工智能研制的河南省６－８月分片大－暴雨短短期自动化预报系统与用Ｔ６３数值预报产品资料采用逐步回归分析法和预测误差平方和最不上准则两种选取回归自变量的方法，建立处分片预报方程的综合判别预报。（３）在１９９５，１９９６年７－８月业务预报中试验结果。     

NUMERICAL SIMULATION OF OZONE DISTRIBUTIONS AND ITS VARIATION MECHANISM*

A 2-D global chemistry-transport model is set up in this paper.The model simulates the atmospheric ozone distributions well with specified dynamical conditions.The analysis of ozone variation mechanism shows that ozone is chemically in quasi-equilibrium except for the polar night region where the variation of ozone concentration is under the control of dynamical processes,that the oxygen atoms which produce ozone are mainly provided by the photolysis of O₂ in the upper stratosphere and by the photolysis of NO₂ in the lower stratosphere and the troposphere.and that the ozone is destroyed mainly by NO_x:the reactions between NO_x and O₃ and the odd oxygen cycle contribute 80% to more than 90% of the ozone destruction.     

科尔沁沙地巴克窑地区近150年的环境演变*

在沉积和花粉分析的基础上,对科尔沁沙地东南部巴克窑地区过去150年的植被和环境演变进行了重建。巴克窑等湖泡的诞生时间是在上个世纪前期,约1837年前后。这个时间也正是科尔沁沙地东南部地区首次大规模人口移入和垦荒年代。突然增加的人类活动导致了沙丘植被的迅速破坏,而植被减少和沙丘活化引起区域水文循环的重新调整,即原来通过植物蒸腾作用输出的水量明显减弱,致使地下潜水位上升,形成一系列湖泡。以后,沙地系统的演化主要是在人类活动、气候和系统内部反馈机制的共同作用下完成的。     

综合物探在鄱阳湖铁路特大桥勘察中的应用

鄱阳湖铁路特大桥桥址位于鄱阳湖入长江的交汇处。该区地质情况复杂,断裂构造十分发育,因此地质勘探对桥址方案的比选显得尤为重要。此次有效地利用了综合物探,采用多种方法查明了岩性分区和地质构造格局,取得了良好的地质效果。充分显示了综合勘探、综合物探的优势。     

单道扫描电感耦合等离子体发射光谱法测定大洋标准物质中稀土元素

采用单道扫描等离子体发射光谱法测定了大洋多金属结核及深海沉积物中的稀土元素与钪，比较了不同功率下各稀土元素的检测限，研究了低功率下的稳定性，拟定了可靠的样品处理方法。方法经多金属结核及深海沉积物国家标准ＧＢＷ０７３１３、ＧＢＷ０７２４９分析验证，结果与标准值相符。测定精度（ＲＳＤ）在１３％～５３％。已用此法为第２批多金属结核和深海沉积物标准物质提供了定值数据，其结果无剔除值     

安山岩中黄铜矿矿石分析和制硫酸铜工艺的研究

安山岩中的黄铜矿是庐江中生代陆相火山热液型铜矿床的原生矿，矿石中主要伴生黄铁矿及少量斑铜矿、赤铁矿和褐铁矿。物相分析结果，黄铜矿的粒度很细，只有细磨才能单体解离；它在矿石中分布极不均匀，且与脉石矿物接触疏松，适于粗磨抛尾。物性分析结果，黄铜矿在４００～５３０℃、斑铜矿在４５０～６００℃、黄铁矿在５００～６８０℃氧化分解。实验研究表明，矿石经磨碎磁选，大部分的粗粒级的铁矿物能够回收；粗磨抛尾可获得铜、硫的粗精矿；然后再经硫酸化焙烧、酸浸、过滤、提纯、浓缩结晶可制得工业级硫酸铜。浸渣做炼铁原料，黄钾铁矾做Ｆｅ２Ｏ３颜料，有时还可回收金、银。