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1.
陈千盛  沈思法 《台湾海峡》1998,17(2):214-218
本文分析了福建地区大风的时空变化。结果表茫,沿海和岛屿大风明显多于内陆,高山之顶多于河谷山地。沿海、岛屿秋冬大风多,强度弱,灾害轻;春在风较少,强度大,灾害重。内陆山地大风春夏多,强度大;秋冬少、强度弱。造成大风的天气型有热带气旋型、冷空气和热带气旋共同影响型、气旋型、入海高压型、北低南高型、雷雨前型、龙卷风型。  相似文献   

2.
利用逐时雨量分布图,对登陆珠江三角洲的热带气旋暴雨尺度特征进行分类,对比和合成分析,实际资料证实了大范围的热带气旋暴雨是由若干中尺度雨团,雨带造成的,纯热带气旋环流形成的中尺度雨团、雨带具有与热带气旋云带大体一致的分布特征;有冷空气与之配合时,热带气旋环流北缘形成东西向的中尺度雨带;热带气旋登陆后的3h可能出现最大中尺度雨团;随热带气旋环流的填塞减弱,中尺度雨团也逐渐减弱消失;山地对中尺度雨团的移  相似文献   

3.
利用逐时雨量分布图,对登陆珠江三角洲的热带气旋暴雨中尺度特征进行分类、对比和合成分析。实际资料证实了大范围的热带气旋暴雨是由若干中尺度雨团、雨带造成的,纯热带气旋环流形成的中尺度雨团、雨带具有与热带气旋云带大体一致的分布特征;有冷空气与之配合时,热带气旋环流北缘形成东西向的中尺度雨带;热带气旋登陆后的3h可能出现最大中尺度雨团;随热带气旋环流的填塞减弱,中尺度而团也逐渐减弱消失;山地对中尺度雨团的移动起阻滞加强作用,有利的地形与暖湿气流配合,将激发生成新的中尺度雨带。  相似文献   

4.
2022 年夏季(6—8月)大气环流特征为:北半球极涡呈单极型分布,中高纬度西风带呈3 波型分布,欧亚大陆为“两槽一脊”的环流型。6 月,副热带高压偏南、偏强,不利于热带气旋生成;7—8 月副热带高压北抬西伸,热带气旋开始活跃并影响我国近海。我国近海有18 次8 级以上大风过程,其中热带气旋过程大风有5 次,5 次由入海温带气旋造成,7 次为雷暴大风,另外 1 次由冷空气过程引起。我国北方海域多海雾天气,出现 5 次明显的海雾过程,其中 6 月出现 4 次,7 月出现 1 次。发生 14 次2. 0 m 以上的大浪过程,6 月出现6 次,7 月出现4 次,8 月出现4 次。西北太平洋和南海共有 9 个热带气旋命名,比多年平均偏少 2. 6 个;其他各大洋共有 11 个命名热带气旋生成,分别为:北大西洋3 个、东太平洋8 个。  相似文献   

5.
热带气旋进入北部湾后强度突变的天气气候特征分析   总被引:2,自引:1,他引:2  
本文按近海热带气旋强度突变的标准,对1970~1990年进入北部湾后强度发生突变的热带气旋进行分类统计,发现有如下的气候特征:每年平均有32个热带气旋进入北部湾,其中强度变化不大的占总数的52%;强度突然减弱的占总数的42%;强度突然增强的占总数的6%。强度变化不大和强度突然减弱的发生在5~11月,强度突然增强的发生在8~9月。本文对进入北部湾的热带气旋强度增强的天气类型进行分类,归纳起来分为四种天气类型:副热带高压型;赤道辐合带型;季风低槽型和锋面低槽型,这些结果将对天气预报有很大的帮助  相似文献   

6.
据统计,1960~2002年共有118个热带气旋进入广西近海区域内,其中移动路径怪异的热带气旋有7个。本文着重分析造成热带气旋移动路径怪异的大气环流特征和天气类型,归纳为:双台风影响、副热带高压影响、冷空气影响等三种天气类型。  相似文献   

7.
为分析ENSO对登陆广东省热带气旋影响,选用1951~2016年登陆广东省热带气旋统计数据,分析与ENSO特征值之间的关系.研究结果表明:登陆广东省热带气旋年内变化和年际变化较大,年际变化总体呈现波动下降的趋势;登陆广东省的热带气旋主要集中于粤西沿海,特别是湛江东部沿海区域;厄尔尼诺年登陆广东省热带气旋数(2.74次)低于拉尼娜年热带气旋数(4.50次),但登陆的热带气旋强度相对较高;登陆广东省的热带气旋与Nino3.4海洋表面温度距平值( SSTA )、海洋尼诺指数( ONI )和南方涛动指数( SOI )等ENSO特征值呈现显著相关关系.  相似文献   

8.
1949-2017年南海海域热带气旋强度和路径快速变化统计特征   总被引:1,自引:1,他引:0  
为进一步认识南海地区热带气旋强度和路径快速变化的统计特征,利用中国气象局上海台风研究所整编的1949–2017年的热带气旋最佳路径数据集,统计分析了不同强度等级热带气旋发生强度和路径快速变化的特征。结果表明:(1)由强热带风暴快速加强为台风、以及由台风快速加强为强台风是热带气旋强度快速加强发生频率最多的事件;强度快速加强次数以1次居多,一般不会超过2次;但大部分途经南海的热带气旋出现快速加强时都在南海以外的地区,在南海出现快速加强的概率仅为9.8%。(2)不同强度的热带气旋,其强度的维持时间长短对其强度快速加强有重要影响,一般在该强度的前24 h是快速加强的最佳阶段,当其中心气压下降速度超过?12.0 hPa/(6 h)时容易出现台风级别或以上的强度快速加强,且热带气旋快速加强容易出现在海温偏高地区。(3)南海地区热带气旋路径的偏转主要出现在西行路径中,其中以5°~30°的偏转为最常见,占到全部热带气旋总数的48.65%,不过,按照定义的路径快速转向标准,路径快速转向的概率仅有15.13%。随着热带气旋强度的增强,南海地区发生路径快速转向的频次迅速减少,路径快速转向主要出现在近海岸地区和南海中北部偏东区域。这些结果进一步细化和丰富了对南海地区热带气旋强度和路径快速变化的认识。  相似文献   

9.
刘爱国  吴阳 《海洋通报》2003,22(4):87-91
ENSO事件是海—气相互作用的一种突出表现。它的出现会引发世界范围内的气候异常,从而导致台风活动的异常。根据1884—2000年的台风资料,采用统计的方法分析厄尔尼诺(暖事件)和反厄尔尼诺(冷事件)与登陆斗门—厓县热带气旋的关系得出:中等强度的冷、暖事件与登陆斗门—厓县热带气旋个数关系不明显:而在强或弱冷、暖事件中,冷事件影响年登陆斗门—厓县的热带气旋明显偏多。特别是在冷、暖事件影响下,登陆斗门—厓县热带气旋异常偏多年中,冷事件影响年占了64%。  相似文献   

10.
近58a来影响和登陆浙江的热带气旋统计特征分析   总被引:3,自引:0,他引:3  
本文利用1949-2006年热带气旋资料,对58a来影响和登陆浙江热带气旋的登陆位置、登陆时间的年际、月际和日变化、登陆后的移速及路径变化与降水中心分布的关系、登陆后维持和衰减情况等进行了统计分析.统计结果表明:影响和登陆浙江的热带气旋有较明显的年际、月际和日变化特征;登陆浙江的热带气旋陆上维持时间与登陆时的强度正相关,登陆后12h内热带气旋衰减较快;登陆后移向偏北分量大的或移速加快的热带气旋,主要降水区出现在路径右侧的可能性大.  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
双壳贝类血淋巴中儿茶酚胺的检测方法初步研究   总被引:1,自引:0,他引:1  
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。  相似文献   

14.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明:黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。  相似文献   

16.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.  相似文献   

18.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

19.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

20.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

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