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81.
At the interface between the lower atmosphere and sea surface, sea spray might significantly influence air-sea heat fluxes and subsequently, modulate upper ocean temperature during a typhoon passage. The effects of sea spray were introduced into the parameterization of sea surface roughness in a 1-D turbulent model, to investigate the effects of sea spray on upper ocean temperature in the Kuroshio Extension area, for the cases of two real typhoons from 2006, Yagi and Soulik. Model output was compared with data from the Kuroshio Extension Observatory (KEO), and Reynolds and AMSRE satellite remote sensing sea surface temperatures. The results indicate drag coefficients that include the spray effect are closer to observations than those without, and that sea spray can enhance the heat fluxes (especially latent heat flux) considerably during a typhoon passage. Consequently, the model results with heat fluxes enhanced by sea spray simulate better the cooling process of the SST and upper-layer temperature profiles. Additionally, results from the simulation of the passage of typhoon Soulik (that passed KEO quickly), which included the sea spray effect, were better than for the simulated passage of typhoon Yagi (that crossed KEO slowly). These promising 1-D results could provide insight into the application of sea spray in general circulation models for typhoon studies. 相似文献
82.
83.
Heavy metal contamination of cultivated wetland soils along a typical plateau lake from southwest China 总被引:3,自引:0,他引:3
Junhong Bai Baoshan Cui Zhifeng Yang Xiaofeng Xu Qiuyi Ding Haifeng Gao 《Environmental Earth Sciences》2010,59(8):1781-1788
Topsoil (0–20 cm) samples were collected from four cultivated wetlands including Northern and Western Fields (about 30-year
tillage), and Southern and Western Fields (about 20-year tillage) along the Yilong Lake of China in October, 2005. Total concentrations
of As, Cr, Cu, Pb, and Zn were determined using the inductively coupled plasma atomic absorption spectrometry in order to
assess contamination status in four sampling plots. Results showed that the average concentrations of these heavy metals in
Northern and Western Fields were significantly (P < 0.01) higher than those in reference soils, while they were generally lower in Southern and Eastern Fields. All the mean
concentrations of heavy metals were lower, except that the average concentrations of As and Cr in Northern Field slightly
exceeded the soil quality guidelines. The contamination indices showed low-contamination levels for As, Cu, Pb, and Zn in
Northern and Western Fields, while no contamination levels could be observed in Southern and Eastern Fields. As for Cr, they
showed moderate-contamination levels in Northern Field, but low or no contamination levels in other three Fields. The integrated
contamination index values indicated Northern and Western Fields were moderately contaminated, while Southern and Eastern
Fields were less contaminated. The same contamination sources of these heavy metals were identified in these fields using
factor- and cluster analysis. 相似文献
84.
85.
We use the hydrographic data obtained during the joint survey of the Yellow Sea by the First Institute of Oceanography, China and the Korea Ocean Research and Development Institute, Korea, to quantify the spatial structures and temporal evolution of the southern Yellow Sea Cold Water Mass (YSCWM). It is indicated that the southern YSCWM is a water mass that develops in summer and decays in fall. In winter, due to the intrusion of the Yellow Sea Warm Current (YSWC), the central area (approximately between 34°N and 35°N, 122°E and 124°E) of the Yellow Sea is mainly occupied by relatively high temperature water (T>10 °C). By contrast, from early summer to fall, under the seasonal thermocline, the central area of Yellow Sea is occupied by cold water (T<10 °C). In summer, the southern YSCWM has two cold cores. One is formed locally southeast of Shandong Peninsula, and the other one has a tongue-like feature occupying the area approximately between 34°N and 37°N, 123°E and 126°E. The bottom layer temperature anomalies from February to July in the cold tongue region, along with the trajectories of the bottom floaters, suggest that the cold water mass in the northeast region has a displacement from the north to the central area of the Yellow Sea during the summer. 相似文献
86.
西北地区近期地壳水平运动与构造变形特征 总被引:3,自引:0,他引:3
利用截止2004年的西北地区GPS和跨祁连-龙首山构造带的红外测距观测资料,借助最小二乘配置、弹性块体边界负位错模型及单一力源反演,研究昆仑山口西8.1级大震前后西北地区水平形变应变场的动态演化特征;尤其是大震3年后,即当前的构造形变与应力场态势;获取活动块体及其边界断裂上可能反映中强以上孕震背景的高应变能积累区、段,以及可能的潜在震源。结果表明:青藏块体北缘地区经8.1级大震后的短期松弛和调整,目前正在恢复印度板块北东向碰撞推挤背景场的主控作用。而北天山构造带中段及其与西段的交汇区、南天山构造带中西段及其与西昆仑构造带的交汇区、阿尔金断裂中段、祁连山构造带中东段及其与海原断裂的交汇区、西秦岭北缘断裂与庄浪河断裂东南延伸线的交汇区域等具有相对高应变能积累背景;临泽与海原这两个地区也反映一定程度的应变能积累状态。 相似文献
87.
崔笃信 《大地测量与地球动力学》1994,(1)
地壳纯变形分为剪切变形和扩张变形。在前人研究的基础上提出了仅利用复测水准资料求出描述地壳剪切变形和扩张变形指标的方法和步骤,所得的定量指标不受基准的影响,受测量累积误差的影响亦很小,能客观地反映地壳变形的特征。通过理论和实例证明:以一点周围变形分量的最大值代表该点周围垂直面的变形程度比其平均值更能突出变形信息。最后根据实例计算结果分析了剪切变形分量、扩张变形分量与形变速率、构造地震的关系。 相似文献
88.
Song Wang Hao-Tong Zhang Zhong-Rui Bai Hai-Long Yuan Mao-Sheng Xiang Bo Zhang Wen Hou Fang Zuo Bing Du Tan-Da Li Fan Yang Kai-Ming Cui Yi-Lun Wang Jiao Li Mikhail Kovalev Chun-Qian Li Hao Tian Wei-Kai Zong Heng-Geng Han Chao Liu A-Li Luo Jian-Rong Shi Jian-Ning Fu Shao-Lan Bi Zhan-Wen Han Ji-Feng Liu 《天文和天体物理学研究(英文版)》2021,(11):213-232
From Oct.2019 to Apr.2020,LAMOST performed a time-domain(TD)spectroscopic survey of four K2 plates with both low-and medium-resolution observations.The low-reso... 相似文献
89.
????GM(1,1)?????????????????????????????????????????GM(1,1)?????????????????????????GM(1,1) ??????GM(1,1)??PGM(1,1)?????GM(1,1)????????????б???????????????????????GM(1,1)???????????? 相似文献
90.