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为了解南海与季风的相互作用，用实测资料分析了南海中北部次表层水温与南海夏季风和广东旱涝的关系。结果表明：南海中北部次表层水温在2月偏暖（冷）时，南海夏季风爆发偏早（晚）是主要现象；南海中北部次表层水温在8月偏暖（冷）时，南海夏季风结束偏晚（早）是主要现象。西沙平均水温时间系列的距平值自1978年1～3月开始有上升趋势，年平均水温距平值上升趋势出现在1979年。结论：南海中北部在2月次表层水温持续编暖（冷）时，夏季风爆发偏早（晚）、广东出现洪涝（干旱）灾害是主要现象。 相似文献
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一种局地非线性气候动力统计模型及其预报试验 总被引：1，自引：5，他引：1
根据反演建模理论，在引入一次样条函数的基础上，设计了一种局地非线性气候动力统计模型及其一整套反演方案。其实质是用逐段线性化的研究局地气候演化的非线性特征。作为初步试验，利用云南省18个测站1956年1月－1990年12月逐月温度距平和逐月雨量距平率的时间序列，反演得到一组近似描述云南省局地气候系统的非线性动力统计方程，应用反演获得的此非线性动力统计方程进行了云南省18个测站1991年1月－1994年12月逐月温度距平和逐月雨量距平率的预报试验。试验结果表明，温度距平和雨量距平率的拟合准确率分别约为78％和64％；温度距平和雨量距平率的外推预报准确率分别为75％和63％。表明此模型具有一定的拟合和预报能力，同时具有良好的稳定性。 相似文献
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针对海南西沙新一代天气雷达防雷工程的需要,在分析基本情况的基础上,按照国标和行标规范要求,确定了西沙雷达塔楼内外防雷措施,重点介绍了西沙雷达塔楼内外部防雷工程方案和具体实施方法。 相似文献
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为探索西沙和南沙海气热通量时间演变特征，用海洋站观测资料计算了1998年南海夏季风爆发前后，海气界面热量交换值及海面热收支年循环。结果表明：季风爆发前，西沙海气界面热量交换较弱，水汽通量较小，以海洋获得热量为主；季风爆发后，海气界面热量交换接近平衡。南沙全年主要是海洋对大气加热。南沙和西沙海面吸收短波辐射年周期特征明显，极大值出现在冬半年。西沙海面潜热通量存在半年周期特征，极大值也是出现在冬半年。结论：冬半年海面热通量变化对翌年的季风将产生重要影响。 相似文献
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根据国家海洋局南海分局的Marex(马瑞克斯)数据浮标观测资料、南海断面线 调查资料和西沙海洋站资料，计算了南海海气界面热量交换值。研究结果表明:不论是夏季还是秋季，在台风环流内海气界面热量交换均非常强烈，主要贡献来自潜热通量(Qv)，位于(20.49°N，114.14°E)附近海域。夏季台风环流内显热通量(Qk)出现负值，海面有效反射辐射(Qe)出现减弱现象；秋冬季节台风环流内Qk量值增加显著均为正值，Qe有加强的现象。分析实测资料发现:1961～1989年8次ElNino事件过程中，西沙海洋站水温比赤道太平洋水温提早出现增暖现象的有4次，水温推迟出现增暖现象的也是4次。西沙海洋站水温增暖出现在12月的仅有1次。ElNino事件发生后，南海水温异常增暖，但是海气界面热量交换反而减弱。 相似文献
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分别以每日２４次、１２次、８次、４次采样密度统计了成都、重庆两地的各类大气稳定度频率分布。结果指出：对年平均而言，采样密度对两地各类稳定度频率统计无影响，每日４次采样已足够。采样密度对冬季稳定度频率影响较大，应加密为每日８次样李即可满足精度要求。在精细研究稳定度频率的日变化时，应以每日２４次采样为宜。为保证稳定度频率统计的正确和环境评价的精度，确定合宜的污染物排放时间，对不同的研究问题，应取不同的 相似文献
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西沙群岛基本气候特征分析 总被引：3，自引：0，他引：3
西沙处于南海西部，了解它的天气气候特征，无论对于海岛及其邻近海域的科学考察和资源开发，还是对于南海季风的研究，都有重要的意义。本文利用30年（1959～1988年）降水，地面气温、地面风资料，统计分析它们的年际变化和季节变化特征。1气温的统计特征1．1气温的年际变化西沙的30年年平均气温是25．56℃。根据西沙各年年平均气温的30年演变图（图略），结合距平果加方法［1］分析，30年可分为两个阶段：前20年（1959～1978年）为偏冷阶段，期中1971年最冷，只有25．82℃；后10年（1979～1988年）为偏暖期，其中1983和1987年最暖，达27．… 相似文献
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本文用2005年6月吉林省人工影响天气办公室外场试验基地(总面积104km2,正方形区域)10km站距降雨量自记资料,分析了雨量站距离对估算区域降雨量的影响。结果如下:总体上(气候上)不同站距估算的区域降雨量相近,但每个个例不同站距估算的区域降雨量差别较大。与10km站距估算的区域降雨量比较,每个个例各时段不同站距估算的区域降雨量都存在相对误差,20km和30km站距误差接近,40km站距误差约比它们大1倍。随着时间段不同,20km和30km站距估算的区域降雨量误差率为27%～44%,40km站距误差率为44%～85%。各站距随着时间段的增加误差率减小。20km和40km站距个例估值偏小的多,30km站距个例估值偏大的多。这些结果反映出雨量站距离对估算区域降雨量影响的趋势。 相似文献
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通过对南海腹地岛屿测站和南海北岸测站气溶胶样品中水溶性成分的分析，以及与华南大陆清洁测点和城市测点的对比，结果表明:海岛测点气溶胶总质量与诸离子浓度均大大低于海岸与大陆测点。其分布以三峰型出现的比较多，海岛与海岸气溶胶中水溶性成分以SO2-4，Cl-与Ca2+，Na+为含量比重最大的离子成分；与华南大陆测点相比，Cl-，Na+比重显著增加而NH+4的含量比重有所下降。 相似文献
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广州气溶胶质量谱与水溶性成分谱的年变化特征 总被引：21，自引：5，他引：21
广州气溶胶质量谱与水溶性成分谱的年变化特征吴兑，陈位超（广州热带海洋气象研究所，广州，５１００８０）近年来，我们曾在粤、桂、琼三省华南广大地区采集并分析了大气气溶胶分级样品，从气溶胶参与雨水酸化过程，吸湿性气溶胶作为凝结核的作用，以及海岸地带吸湿性粒... 相似文献
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The dependence of precipitation amount, acidity, and ionic composition on the atmospheric circulation is studied based on
the computation of the back trajectories over the period of 1982–1993. Quantitative estimates of basic parameters of trajectories
are derived, and their significant difference in the summer and wintertime is considered. The trajectory frequency for the
cases with precipitation in the center of European Russia is computed at the regular grid points depending on the diurnal
precipitation amount, acidity, and sulfate/chloride ratio. It is shown that in case of abundant precipitation both in summer
and winter the highest frequency of trajectories is observed in the same regions. In the case of low precipitation, seasonal
differences are observed. It is revealed that precipitation with pH > 5 is mostly connected with the air inflow from Scandinavia
and the north of European Russia, while during the trajectory passage over Central and Southern Europe pH < 5 prevails in
precipitation. The chlorine ions prevail most often when trajectories pass over central regions of the Mediterranean and of
Middle Asia and (although somewhat less) over Scandinavia and northern Russian seas. 相似文献
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Namrata Das Saroj Sundar Baral Parth Sarathi Mahapatra Trupti Das Gautam Roy Chaudhury Surendra Nath Das 《Theoretical and Applied Climatology》2012,110(1-2):55-63
Precipitation samples collected during 2005–2009 from a rural forest station of Bhubaneswar were analyzed for their chemical composition. The samples were collected through a wet-only (WO) collector and two bulk (B1 and B2) collectors. The ions were evenly balanced indicating good data quality. The overall pH of rainwater was slightly acidic and ~47% of all rain events during the period were acidic (pH?<?5.6). Multilinear regression analysis showed relation between the free acidity (H+) and other components in rainwater. Enrichment factors (EF) of the major components with respect to their sources such as marine and crustal were calculated. Maximum EF was observed for NO 3 ? for both marine and crustal sources for all the three collectors. Source apportionments were also carried for the ions. Trend analysis showed continuous increase in most of the ions over years during the study period driven by anthropogenic emissions. Statistical/factorial analysis established correlation among different ions. 相似文献
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Peter Bräuer Andreas Tilgner Ralf Wolke Hartmut Herrmann 《Journal of Atmospheric Chemistry》2013,70(1):19-52
A new detailed multiphase halogen mechanism, the CAPRAM Halogen Module 2.0 (HM2), has been developed and coupled to the multiphase chemistry mechanism RACM-MIM2ext/CAPRAM 3.0n. The overall mechanism comprises 1,705 reactions including 595 reactions of the HM2. Halogen chemistry box model studies have been, for the first time, performed with a non-permanent cloud scenario for pristine open ocean regions in mid-latitudes. Moreover, detailed time-resolved reaction flux analysis has been used to investigate the multiphase halogen reaction cycles in more detail. Clouds significantly change the multiphase halogen chemical system and new reaction cycles are proposed for in-cloud conditions. While most gas phase concentrations are decreased for chlorine and iodine species, they are increased for bromine. Flux analyses determined the relative contributions of the methylene dihalides CH2IX (X = Cl, Br, I) as the main I atom source with a contribution of about 80 % to the total iodocarbon sources. Furthermore, HOI was confirmed to be important for chlorine activation. It is shown that 25 % of the ozone loss can be attributed to halogens. VOC oxidation by halogens is important as halogens account for about 20 % of the methane oxidation and up to 80 % of the oxidation of other VOCs. In other cases, enhanced VOC and VOC oxidation product concentration levels were found. For example, 15 % of the methyl peroxyl radicals are formed after the reaction of chlorine atoms with methane or methyl hydroperoxide. In the aqueous phase, changes in the oxidation of organics do only occur for highly oxidised organics without a C-H bond. For example, over 80 % of oxalic acid are oxidised by electron transfer with Cl2 ? in deliquescent particles during non-cloud periods. 相似文献
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PRABIR K. PATRA SHYAM LAL VARUN SHEEL B. H. SUBBARAYA CHRISTOPH BR&#;HL REINHARD BORCHERS PETER FABIAN 《Tellus. Series B, Chemical and physical meteorology》2000,52(3):934-946
Balloon‐borne cryogenic air sampler experiments have been conducted from a tropical (Hyderabad, 17.5°N) and a midlatitude (GAP, southern France, 44°N) station since 1987 in the altitude range of about 8‐35 km. Air samples are analysed at the Max Planck Institute for Aeronomy (MPAE) and Physical Research Laboratory (PRL) using various gas chromatographic techniques to obtain the vertical distributions of several halogenated source gases and long‐lived dynamical tracers. These observations are used to determine the stratospheric partitioning of the chlorine species into their organic and inorganic forms for the altitude range of 20 to 35 km. Distributions of inorganic chlorine indicate increase in their abundances with altitude, latitude and time. Mixing ratio correlations of organic and inorganic chlorine with N2 O have been obtained which also suggest that the rate of increase in inorganic halogens component in the stratosphere is larger than the increase rate of total organic halogen. This supports previous assessments that halogen‐induced ozone depletion will continue to be observed for a few more years, despite the decrease of halocarbon loading into the stratosphere since 1994. 相似文献
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文章分析了1998年夏季我国长江、嫩江、珠江流域发生的严重洪涝灾害的气象、水文特征及其成因。6月中、下旬珠江、长江、嫩江流域出现了持续性强降水, 局部地区下了大暴雨; 7月下旬长江流域出现了“二度梅”, 湖南、湖北和江西省普降暴雨; 8月上半月嫩江流域再次出现持续性强降水。频繁的强降水使长江、嫩江、华南西江等干、支流水位迅猛上涨, 支流河水不断涌入干流, 使得干流洪峰迭起。雨水和洪峰迭加, 引发了百年一遇的大洪水。1998年7月副热带高压南落是造成长江流域“二度梅”的主要原因。副热带高压、南海季风涌、中高纬冷空气和从青藏高原东移的中尺度对流系统 (MCS) 等4个因子的最佳组配, 有利于长江流域出现持续性强降水。 相似文献
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利用地基双通道微波辐射计遥感青藏高原大气云水特征 总被引：6，自引：1，他引：6
利用1997年春季西宁市地基双通道（22．235和35．3GHz)微波辐射计观测的资料，分析了不同月份、不同天气条件下的大气总含水量（V）和云中液态水积分含量（L）的分布规律。结果表明，在相同天气条件下，L值3－5月均呈逐渐递增的趋势，增加幅度一般为20％－40％，V值变化幅度很小；春季高原L值大约只有V的1%。与河北省的资料进行对比后发现，L值基本相当，而V值高原只有平原地区的30％－50％。 相似文献