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《海洋气象学报》2016,(4)
根据海阳1961—2010年气温、降水量、日照、相对湿度等气象资料,应用气候倾向率、Mann-Kendall突变检测法、滑动t检验法,对海阳市气候变化及规律进行了分析。结果表明:历年平均气温、平均最高气温、平均最低气温、极端最低气温在过去的50a间呈显著的上升趋势,历年极端最高气温的上升趋势不显著,年代际变化特征突出;年降水量呈缓慢的减少趋势,变化趋势不显著,年代际间分布不均,变化较大,年降水量减少的原因是夏季和秋季降水减少;日照时数呈显著减少趋势,发生突变的时间点是2004年;年平均相对湿度呈现显著减少趋势,发生突变的时间点是1977年,秋季湿度减少最为明显。 相似文献
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青岛近百年气温变化特征 总被引:6,自引:0,他引:6
为深入了解气候变化规律及探讨气候变化原因,根据1900~2002年青岛月平均气温资料,分析了103年以来青岛的气温变化特征。分析结果表明:百年来,青岛平均气温呈明显上升趋势,各季节也是增温趋势,冬季增温最大。最高气温和最低气温也都呈明显上升趋势,其中最低气温的变化幅度大于最高气温的变化幅度。对比2次暖锋期的增温特点发现,20世纪40年代的增温主要是春秋季节的增温造成的,而20世纪90年代以后的增温期冬季成为主导因素,同时都是最低气温贡献大,即增温都是在夜间。日较差则呈下降趋势。青岛的气温在1988年发生了突变。另外,青岛气温还有准20年周期振荡的特征。 相似文献
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2012年中国沿海海平面上升显著成因分析 总被引:3,自引:0,他引:3
2012年,中国沿海海平面变化最突出的特点是海平面升高显著。海平面总体比常年高122mm,较2011年偏高53mm,达1980年以来最高位。本文使用中国沿海及西北太平洋区域近30a的水位、海温、气温、气压和风等水文气象资料,详细分析了中国沿海海平面2012年异常偏高的成因。结果表明:2010-2012年中国沿海海平面处于2~3a、8~9a和准19a周期震荡的高位,几个周期震荡高位叠加,对海平面上升起了明显的影响;2012年,沿海气温和海温分别较常年偏高0.4℃和0.3℃,气压较常年低1.2hPa,气压达历史最低位;2012年,中国南海夏季风爆发时间较常年偏早,结束较常年偏晚,季风持续时间较常年偏长,导致2012年5-6月和8月,在黄海和东海海域,东北风持续偏强,南海海域南风偏强,风场的异常导致黄海、东海和南海沿海海水长时间堆积,是造成海平面升高的原因之一;2012年,热带气旋登陆时间集中,影响范围广,北上和影响东北地区的台风数量均为历史之最,特别是2012年8月,有6个热带气旋相继影响我国沿海,对当月海平面升高影响明显;另外,2012年副热带高压偏北、偏东、偏弱的特点对东海和南海的海平面上升也有一定影响。 相似文献
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图们江流域气温的低频变化特征分析 总被引:2,自引:0,他引:2
用奇异谱(SSA)结合Mann-Kendall法分析了图们江流域近50a气温的低频变化特征。结果表明,图们江流域的气温有明显的年际周期振荡和上升的长期趋势变化及突变,年际振荡周期主要是8a、准3~4a和准2a。3~4a的周期振荡主要与ENSO有关,且其变化超前ENSO的年际变化;而准2a振荡(QBO)则主要与印度洋海洋-季风系统的低频振荡和东亚大槽的强度变化有关,并且都表现为最大滞后相关关系。气候突变发生在1972年,1972年以后年平均气温距平值由1972年以前的-0.36℃上升为0.22℃。1972年以前呈波动下降趋势,1972年以后呈上升趋势,但1953~2002年总体上表现为上升趋势。 相似文献
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采用美国NCEP-CFSR数据库资料,提取了1979—2010年的海平面大气要素场,在中国南海区域(0°~25°N、105°~125°E)和黄岩岛附近点(15°N、118°E),按日、月、年统计了32 a间海平面气压、海面2 m气温、海面2 m相对湿度、海面10 m风场基本气象要素特征。分析发现:黄岩岛及邻近中国南海区域属于赤道带、热带海洋性季风气候,其气候特征是:(1)海平面气压呈北高南低、冬季高夏季低的分布形势;黄岩岛日平均海平面气压冬季约为1 012 hPa,其他季节约为1 008 hPa,年平均海平面气压变化具有准5 a的周期;(2)全年平均气温较高,分布呈现北低南高,大陆低海面高,冬季低夏季高的特点;黄岩岛海面2 m气温日变化较小,年平均值约为27~28℃,年际变化上具有整体增加的趋势;(3)全年相对湿度较大,基本在60%以上,随季节变化明显,冬季较小,夏季较大;黄岩岛日平均相对湿度为80%,总体也具有略微增大的年际变化趋势;(4)受季风影响明显,冬季盛行东北季风,平均风速约为10~12 m/s,夏季盛行西南季风,平均风速约为4~8 m/s;黄岩岛海面风速的变化具有2.5~5 a的变化周期,年平均风速在5.3 m/s上下波动。 相似文献
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利用福建沿海几个主要验潮站数据与法国空间局(CNES)AVISO多卫星融合资料分析了福建近海及其周边海域海平面的时、空变化特征及主要模态,并简要分析福建近海海平面变化趋势.得到如下结论:近54a(1960~2013年)福建沿海相对海平面上升约2 mm/a,福建沿海海平面变化存在显著的季节变化和2~3a及6~8a的年际变化特征,这与ENSO和长周期天文分潮的变化周期较为吻合;对比同期卫星高度计资料和潮位站资料(1993~2012年)发现,卫星高度计与潮位站分析结果基本一致;卫星高度计和潮位站分析结果表明,福建沿海区域海平面近20a平均线性变化趋势约为4 mm/a. 相似文献
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Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China 总被引:1,自引:1,他引:0
L E ZHANG Lei CHEN Min QIU Yusheng XING N YANG Weifeng LI Yanping HUANG Yipu 《海洋学报(英文版)》2008,27(1):29-41
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium ( 〈 0.4 μm) exis- ted in the low molecular mass fraction ( 〈 10 000 u), and the colloidal uranium-238 (10 000 u -0.4 μm) only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases ( 〉 0.4 μm), the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows: 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows : 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value (1.0). The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic 相似文献
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Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements. 相似文献
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对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。 相似文献
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《Marine Policy》2013
Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas. 相似文献
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JIN Xianglong 《海洋学报(英文版)》2013,32(12):1-3
In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future. 相似文献
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湄洲湾夏季的初级生产力 总被引:2,自引:3,他引:2
湄洲湾1992年夏季的叶绿素a,三磷酸腺苷,碳比积累速率,初级生产力的变化范围和均值分别为0.45-4.72,1.49mg/m^3;0.12-1.07,0.31μg/dm^3;0.06-0.58,0.34d^-1;0.07-0.34,0.21m/(m^2.d)。叶绿素a与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素a三磷本能腺苷的比值为4.8,湄洲湾夏季浮游植物的生长受氮不足 相似文献
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In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (Kd) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate. 相似文献