排序方式: 共有18条查询结果,搜索用时 31 毫秒
11.
Estimation of wind-forced internal seiche amplitudes in lakes and reservoirs, with data from British Columbia, Canada 总被引:2,自引:0,他引:2
Craig L. Stevens Gregory A. Lawrence 《Aquatic Sciences - Research Across Boundaries》1997,59(2):115-134
Analyses of observations from four lakes in British Columbia, Canada, compare estimates of the amplitude of thermocline deflections
to predictions of wind-driven internal seiche amplitudes made using the Wedderburn number,W. The study sites range from the 750 m diameter Brenda Mines pit-lake to the 107 km long Kootenay Lake. Causal filtering of
the wind data with a frequency cut-off based on the fundamental baroclinic time-scale is critical for correct calculation
ofW. With the filtering incorporated, good comparison betweenW, its integral equivalent the Lake numberL
N
and the observations can be made. In all but the mine pit-lake, upwelling or near-upwelling conditions (W≈1) were encountered. 相似文献
12.
水深测量误差成因分析 总被引:2,自引:1,他引:2
在海洋测量中特别是大比例尺海洋工程水深地形测量中,极易产生水深数据的误盖.根据作者的实践经验,分析了潮汐、风向、海浪和安装等因素对水深数据误差的影响,并提出在海洋测绘实施过程中应注意的问题及解决方法,以减少对测深数据精度的影响。 相似文献
14.
黄、渤海沿岸港湾的假潮及成因探讨 总被引:1,自引:0,他引:1
本文通过对日照港以北黄、渤海沿岸18个港湾8~27年假潮资料的分析,给出了不同区域港湾的假潮状况和成因.在该区域只有龙口港可时常发生100cm左右的大振幅假潮和>150cm甚至>300cm的特大振幅假潮,属假潮特别严重和唯一发生较大危害性假潮港湾;其余分属假潮相对较重、较轻和无假潮港湾,其假潮基本不具危害性或无危害性.分析结果表明其突然而剧烈的风场变化是导致各港湾假潮的直接原因,地理环境差异是造成港湾假潮强弱的关键因素;龙口港100cm左右和>1 50cm的大和特大振幅假潮,是其特殊地理环境、港湾及附近大范围海域骤猛的向港爆发性大风,尤其强雷暴大风涌水在港内骤然积聚和海水惯性振荡的综合结果. 相似文献
15.
16.
渤海、黄海沿岸主要港湾大振幅假潮成因的天气学分析 总被引:1,自引:0,他引:1
对渤海、黄海主要港湾发生的振幅大于50cm(龙口港湾取振幅大于80cm)的65次假潮过程与地面天气图进行对比分析,着重分析了伴随大振幅假潮过程的天气形势.分析结果表明:(1)龙口港湾22次大振幅假潮中有19次与雷暴天气(其中有3次伴随有飑线,1次还伴有龙卷)有关,2次与大风天气有关,1次由外海雷暴引起;因此得出雷暴、飑线是引起大振幅假潮的主要原因;雷暴强弱和持续时间长短变化,导致假潮振幅大小及持续时间长短变化;雷暴的季节变化引起大振幅假潮的季节变化;雷暴发生的局地性导致假潮出现的局地性;雷暴传播方向的不同引起大振幅假潮的周期不同.(2)北方气旋型和江淮气旋及西南倒槽型这两种天气类型有利于产生雷暴,并导致大振幅假潮的发生.这两类型分别占62个例的468%和177%. 相似文献
17.
WEI Haiquan HONG Hanjing R.S.J. SPARKS J.S. WALDER HAN Bin Institute of Geology China Seismological Bureau Beijing Department of Earth Sciences Bristol University UK Cascades Volcano Observatory US Geological Survey USA 《《地质学报》英文版》2004,78(3):790-794
Since the eruption of the Tianchi volcano about 1000 years ago, there have been at least 3 to 5 eruptions of small to moderate size. In addition, hazardous avalanches, rock falls and debris flows have occurred during periods between eruptions. A future eruption of the Tianchi volcano is likely to involve explosive interaction between magma and the caldera lake. The volume of erupted magma is almost in a range of 0.1-0.5 km3. Tephra fallout may damage agriculture in a large area near the volcano. If only 1% of the lake water were ejected during an eruption and then precipitated over an area of 200 km2, the average rainfall would be 100 mm. Moreover, lahars are likely to occur as both tephra and water ejected from the caldera lake fall onto flanks of the volcano. Rocks avalanching into the caldera lake also would bring about grave hazards because seiches would be triggered and lake water with the volume equal to that of the landslide would spill out of the existing breach in the caldera and cause flooding 相似文献
18.
大连老虎滩澳的大振幅假潮 总被引:3,自引:0,他引:3
潮汐周期以外的大振幅水位波动(即大振幅假潮),在老虎滩澳时有发生。老虎滩澳位于大连湾侧,是一半封闭深度较浅的三角形小海湾(图1).验潮站位于湾的左岸,距湾顶约1km,水深2.8m.据统计,1980~1994年15年间出现波高大于20cm的假潮共61次。波高超过40cm的为12次。较大振幅事件发生在1994年7月3日,其最大波高为91cm,谱分析显着周期为10min.类似这种小海湾的大振幅假潮在世界其他港湾也经常观测到。其中,以中国的龙口港、日本的长崎港和巴利亚里群岛西岸的锡尤达德拉(Ciu-tadella)港发生的大振幅假潮最为突出。 相似文献